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Diffstat (limited to 'thirdparty/jpeg-compressor/jpgd.cpp')
| -rw-r--r-- | thirdparty/jpeg-compressor/jpgd.cpp | 6252 |
1 files changed, 3165 insertions, 3087 deletions
diff --git a/thirdparty/jpeg-compressor/jpgd.cpp b/thirdparty/jpeg-compressor/jpgd.cpp index 62fbd1b72d..baf6ea0484 100644 --- a/thirdparty/jpeg-compressor/jpgd.cpp +++ b/thirdparty/jpeg-compressor/jpgd.cpp @@ -1,27 +1,53 @@ -// jpgd.cpp - C++ class for JPEG decompression. -// Public domain, Rich Geldreich <richgel99@gmail.com> +// jpgd.cpp - C++ class for JPEG decompression. Written by Richard Geldreich <richgel99@gmail.com> between 1994-2020. +// Supports progressive and baseline sequential JPEG image files, and the most common chroma subsampling factors: Y, H1V1, H2V1, H1V2, and H2V2. +// Supports box and linear chroma upsampling. +// +// Released under two licenses. You are free to choose which license you want: +// License 1: +// Public Domain +// +// License 2: +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// // Alex Evans: Linear memory allocator (taken from jpge.h). -// v1.04, May. 19, 2012: Code tweaks to fix VS2008 static code analysis warnings (all looked harmless) +// v1.04, May. 19, 2012: Code tweaks to fix VS2008 static code analysis warnings +// v2.00, March 20, 2020: Fuzzed with zzuf and afl. Fixed several issues, converted most assert()'s to run-time checks. Added chroma upsampling. Removed freq. domain upsampling. gcc/clang warnings. // -// Supports progressive and baseline sequential JPEG image files, and the most common chroma subsampling factors: Y, H1V1, H2V1, H1V2, and H2V2. +// Important: +// #define JPGD_USE_SSE2 to 0 to completely disable SSE2 usage. // -// Chroma upsampling quality: H2V2 is upsampled in the frequency domain, H2V1 and H1V2 are upsampled using point sampling. -// Chroma upsampling reference: "Fast Scheme for Image Size Change in the Compressed Domain" -// http://vision.ai.uiuc.edu/~dugad/research/dct/index.html - #include "jpgd.h" #include <string.h> - +#include <algorithm> #include <assert.h> -#define JPGD_ASSERT(x) assert(x) #ifdef _MSC_VER #pragma warning (disable : 4611) // warning C4611: interaction between '_setjmp' and C++ object destruction is non-portable #endif -// Set to 1 to enable freq. domain chroma upsampling on images using H2V2 subsampling (0=faster nearest neighbor sampling). -// This is slower, but results in higher quality on images with highly saturated colors. -#define JPGD_SUPPORT_FREQ_DOMAIN_UPSAMPLING 1 +#ifndef JPGD_USE_SSE2 + + #if defined(__GNUC__) + #if defined(__SSE2__) + #define JPGD_USE_SSE2 (1) + #endif + #elif defined(_MSC_VER) + #if defined(_M_X64) + #define JPGD_USE_SSE2 (1) + #endif + #endif + +#endif #define JPGD_TRUE (1) #define JPGD_FALSE (0) @@ -29,28 +55,28 @@ #define JPGD_MAX(a,b) (((a)>(b)) ? (a) : (b)) #define JPGD_MIN(a,b) (((a)<(b)) ? (a) : (b)) -// TODO: Move to header and use these constants when declaring the arrays. -#define JPGD_HUFF_TREE_MAX_LENGTH 512 -#define JPGD_HUFF_CODE_SIZE_MAX_LENGTH 256 - namespace jpgd { -static inline void *jpgd_malloc(size_t nSize) { return malloc(nSize); } -static inline void jpgd_free(void *p) { free(p); } + static inline void* jpgd_malloc(size_t nSize) { return malloc(nSize); } + static inline void jpgd_free(void* p) { free(p); } + + // DCT coefficients are stored in this sequence. + static int g_ZAG[64] = { 0,1,8,16,9,2,3,10,17,24,32,25,18,11,4,5,12,19,26,33,40,48,41,34,27,20,13,6,7,14,21,28,35,42,49,56,57,50,43,36,29,22,15,23,30,37,44,51,58,59,52,45,38,31,39,46,53,60,61,54,47,55,62,63 }; -// DCT coefficients are stored in this sequence. -static int g_ZAG[64] = { 0,1,8,16,9,2,3,10,17,24,32,25,18,11,4,5,12,19,26,33,40,48,41,34,27,20,13,6,7,14,21,28,35,42,49,56,57,50,43,36,29,22,15,23,30,37,44,51,58,59,52,45,38,31,39,46,53,60,61,54,47,55,62,63 }; + enum JPEG_MARKER + { + M_SOF0 = 0xC0, M_SOF1 = 0xC1, M_SOF2 = 0xC2, M_SOF3 = 0xC3, M_SOF5 = 0xC5, M_SOF6 = 0xC6, M_SOF7 = 0xC7, M_JPG = 0xC8, + M_SOF9 = 0xC9, M_SOF10 = 0xCA, M_SOF11 = 0xCB, M_SOF13 = 0xCD, M_SOF14 = 0xCE, M_SOF15 = 0xCF, M_DHT = 0xC4, M_DAC = 0xCC, + M_RST0 = 0xD0, M_RST1 = 0xD1, M_RST2 = 0xD2, M_RST3 = 0xD3, M_RST4 = 0xD4, M_RST5 = 0xD5, M_RST6 = 0xD6, M_RST7 = 0xD7, + M_SOI = 0xD8, M_EOI = 0xD9, M_SOS = 0xDA, M_DQT = 0xDB, M_DNL = 0xDC, M_DRI = 0xDD, M_DHP = 0xDE, M_EXP = 0xDF, + M_APP0 = 0xE0, M_APP15 = 0xEF, M_JPG0 = 0xF0, M_JPG13 = 0xFD, M_COM = 0xFE, M_TEM = 0x01, M_ERROR = 0x100, RST0 = 0xD0 + }; -enum JPEG_MARKER -{ - M_SOF0 = 0xC0, M_SOF1 = 0xC1, M_SOF2 = 0xC2, M_SOF3 = 0xC3, M_SOF5 = 0xC5, M_SOF6 = 0xC6, M_SOF7 = 0xC7, M_JPG = 0xC8, - M_SOF9 = 0xC9, M_SOF10 = 0xCA, M_SOF11 = 0xCB, M_SOF13 = 0xCD, M_SOF14 = 0xCE, M_SOF15 = 0xCF, M_DHT = 0xC4, M_DAC = 0xCC, - M_RST0 = 0xD0, M_RST1 = 0xD1, M_RST2 = 0xD2, M_RST3 = 0xD3, M_RST4 = 0xD4, M_RST5 = 0xD5, M_RST6 = 0xD6, M_RST7 = 0xD7, - M_SOI = 0xD8, M_EOI = 0xD9, M_SOS = 0xDA, M_DQT = 0xDB, M_DNL = 0xDC, M_DRI = 0xDD, M_DHP = 0xDE, M_EXP = 0xDF, - M_APP0 = 0xE0, M_APP15 = 0xEF, M_JPG0 = 0xF0, M_JPG13 = 0xFD, M_COM = 0xFE, M_TEM = 0x01, M_ERROR = 0x100, RST0 = 0xD0 -}; + enum JPEG_SUBSAMPLING { JPGD_GRAYSCALE = 0, JPGD_YH1V1, JPGD_YH2V1, JPGD_YH1V2, JPGD_YH2V2 }; -enum JPEG_SUBSAMPLING { JPGD_GRAYSCALE = 0, JPGD_YH1V1, JPGD_YH2V1, JPGD_YH1V2, JPGD_YH2V2 }; +#if JPGD_USE_SSE2 +#include "jpgd_idct.h" +#endif #define CONST_BITS 13 #define PASS1_BITS 2 @@ -76,3130 +102,3182 @@ enum JPEG_SUBSAMPLING { JPGD_GRAYSCALE = 0, JPGD_YH1V1, JPGD_YH2V1, JPGD_YH1V2, #define CLAMP(i) ((static_cast<uint>(i) > 255) ? (((~i) >> 31) & 0xFF) : (i)) -// Compiler creates a fast path 1D IDCT for X non-zero columns -template <int NONZERO_COLS> -struct Row -{ - static void idct(int* pTemp, const jpgd_block_t* pSrc) - { - // ACCESS_COL() will be optimized at compile time to either an array access, or 0. - #define ACCESS_COL(x) (((x) < NONZERO_COLS) ? (int)pSrc[x] : 0) - - const int z2 = ACCESS_COL(2), z3 = ACCESS_COL(6); - - const int z1 = MULTIPLY(z2 + z3, FIX_0_541196100); - const int tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065); - const int tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); - - const int tmp0 = (ACCESS_COL(0) + ACCESS_COL(4)) << CONST_BITS; - const int tmp1 = (ACCESS_COL(0) - ACCESS_COL(4)) << CONST_BITS; - - const int tmp10 = tmp0 + tmp3, tmp13 = tmp0 - tmp3, tmp11 = tmp1 + tmp2, tmp12 = tmp1 - tmp2; - - const int atmp0 = ACCESS_COL(7), atmp1 = ACCESS_COL(5), atmp2 = ACCESS_COL(3), atmp3 = ACCESS_COL(1); - - const int bz1 = atmp0 + atmp3, bz2 = atmp1 + atmp2, bz3 = atmp0 + atmp2, bz4 = atmp1 + atmp3; - const int bz5 = MULTIPLY(bz3 + bz4, FIX_1_175875602); - - const int az1 = MULTIPLY(bz1, - FIX_0_899976223); - const int az2 = MULTIPLY(bz2, - FIX_2_562915447); - const int az3 = MULTIPLY(bz3, - FIX_1_961570560) + bz5; - const int az4 = MULTIPLY(bz4, - FIX_0_390180644) + bz5; - - const int btmp0 = MULTIPLY(atmp0, FIX_0_298631336) + az1 + az3; - const int btmp1 = MULTIPLY(atmp1, FIX_2_053119869) + az2 + az4; - const int btmp2 = MULTIPLY(atmp2, FIX_3_072711026) + az2 + az3; - const int btmp3 = MULTIPLY(atmp3, FIX_1_501321110) + az1 + az4; - - pTemp[0] = DESCALE(tmp10 + btmp3, CONST_BITS-PASS1_BITS); - pTemp[7] = DESCALE(tmp10 - btmp3, CONST_BITS-PASS1_BITS); - pTemp[1] = DESCALE(tmp11 + btmp2, CONST_BITS-PASS1_BITS); - pTemp[6] = DESCALE(tmp11 - btmp2, CONST_BITS-PASS1_BITS); - pTemp[2] = DESCALE(tmp12 + btmp1, CONST_BITS-PASS1_BITS); - pTemp[5] = DESCALE(tmp12 - btmp1, CONST_BITS-PASS1_BITS); - pTemp[3] = DESCALE(tmp13 + btmp0, CONST_BITS-PASS1_BITS); - pTemp[4] = DESCALE(tmp13 - btmp0, CONST_BITS-PASS1_BITS); - } -}; - -template <> -struct Row<0> -{ - static void idct(int* pTemp, const jpgd_block_t* pSrc) - { -#ifdef _MSC_VER - pTemp; pSrc; + static inline int left_shifti(int val, uint32_t bits) + { + return static_cast<int>(static_cast<uint32_t>(val) << bits); + } + + // Compiler creates a fast path 1D IDCT for X non-zero columns + template <int NONZERO_COLS> + struct Row + { + static void idct(int* pTemp, const jpgd_block_coeff_t* pSrc) + { + // ACCESS_COL() will be optimized at compile time to either an array access, or 0. Good compilers will then optimize out muls against 0. +#define ACCESS_COL(x) (((x) < NONZERO_COLS) ? (int)pSrc[x] : 0) + + const int z2 = ACCESS_COL(2), z3 = ACCESS_COL(6); + + const int z1 = MULTIPLY(z2 + z3, FIX_0_541196100); + const int tmp2 = z1 + MULTIPLY(z3, -FIX_1_847759065); + const int tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); + + const int tmp0 = left_shifti(ACCESS_COL(0) + ACCESS_COL(4), CONST_BITS); + const int tmp1 = left_shifti(ACCESS_COL(0) - ACCESS_COL(4), CONST_BITS); + + const int tmp10 = tmp0 + tmp3, tmp13 = tmp0 - tmp3, tmp11 = tmp1 + tmp2, tmp12 = tmp1 - tmp2; + + const int atmp0 = ACCESS_COL(7), atmp1 = ACCESS_COL(5), atmp2 = ACCESS_COL(3), atmp3 = ACCESS_COL(1); + + const int bz1 = atmp0 + atmp3, bz2 = atmp1 + atmp2, bz3 = atmp0 + atmp2, bz4 = atmp1 + atmp3; + const int bz5 = MULTIPLY(bz3 + bz4, FIX_1_175875602); + + const int az1 = MULTIPLY(bz1, -FIX_0_899976223); + const int az2 = MULTIPLY(bz2, -FIX_2_562915447); + const int az3 = MULTIPLY(bz3, -FIX_1_961570560) + bz5; + const int az4 = MULTIPLY(bz4, -FIX_0_390180644) + bz5; + + const int btmp0 = MULTIPLY(atmp0, FIX_0_298631336) + az1 + az3; + const int btmp1 = MULTIPLY(atmp1, FIX_2_053119869) + az2 + az4; + const int btmp2 = MULTIPLY(atmp2, FIX_3_072711026) + az2 + az3; + const int btmp3 = MULTIPLY(atmp3, FIX_1_501321110) + az1 + az4; + + pTemp[0] = DESCALE(tmp10 + btmp3, CONST_BITS - PASS1_BITS); + pTemp[7] = DESCALE(tmp10 - btmp3, CONST_BITS - PASS1_BITS); + pTemp[1] = DESCALE(tmp11 + btmp2, CONST_BITS - PASS1_BITS); + pTemp[6] = DESCALE(tmp11 - btmp2, CONST_BITS - PASS1_BITS); + pTemp[2] = DESCALE(tmp12 + btmp1, CONST_BITS - PASS1_BITS); + pTemp[5] = DESCALE(tmp12 - btmp1, CONST_BITS - PASS1_BITS); + pTemp[3] = DESCALE(tmp13 + btmp0, CONST_BITS - PASS1_BITS); + pTemp[4] = DESCALE(tmp13 - btmp0, CONST_BITS - PASS1_BITS); + } + }; + + template <> + struct Row<0> + { + static void idct(int* pTemp, const jpgd_block_coeff_t* pSrc) + { + (void)pTemp; + (void)pSrc; + } + }; + + template <> + struct Row<1> + { + static void idct(int* pTemp, const jpgd_block_coeff_t* pSrc) + { + const int dcval = left_shifti(pSrc[0], PASS1_BITS); + + pTemp[0] = dcval; + pTemp[1] = dcval; + pTemp[2] = dcval; + pTemp[3] = dcval; + pTemp[4] = dcval; + pTemp[5] = dcval; + pTemp[6] = dcval; + pTemp[7] = dcval; + } + }; + + // Compiler creates a fast path 1D IDCT for X non-zero rows + template <int NONZERO_ROWS> + struct Col + { + static void idct(uint8* pDst_ptr, const int* pTemp) + { + // ACCESS_ROW() will be optimized at compile time to either an array access, or 0. +#define ACCESS_ROW(x) (((x) < NONZERO_ROWS) ? pTemp[x * 8] : 0) + + const int z2 = ACCESS_ROW(2); + const int z3 = ACCESS_ROW(6); + + const int z1 = MULTIPLY(z2 + z3, FIX_0_541196100); + const int tmp2 = z1 + MULTIPLY(z3, -FIX_1_847759065); + const int tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); + + const int tmp0 = left_shifti(ACCESS_ROW(0) + ACCESS_ROW(4), CONST_BITS); + const int tmp1 = left_shifti(ACCESS_ROW(0) - ACCESS_ROW(4), CONST_BITS); + + const int tmp10 = tmp0 + tmp3, tmp13 = tmp0 - tmp3, tmp11 = tmp1 + tmp2, tmp12 = tmp1 - tmp2; + + const int atmp0 = ACCESS_ROW(7), atmp1 = ACCESS_ROW(5), atmp2 = ACCESS_ROW(3), atmp3 = ACCESS_ROW(1); + + const int bz1 = atmp0 + atmp3, bz2 = atmp1 + atmp2, bz3 = atmp0 + atmp2, bz4 = atmp1 + atmp3; + const int bz5 = MULTIPLY(bz3 + bz4, FIX_1_175875602); + + const int az1 = MULTIPLY(bz1, -FIX_0_899976223); + const int az2 = MULTIPLY(bz2, -FIX_2_562915447); + const int az3 = MULTIPLY(bz3, -FIX_1_961570560) + bz5; + const int az4 = MULTIPLY(bz4, -FIX_0_390180644) + bz5; + + const int btmp0 = MULTIPLY(atmp0, FIX_0_298631336) + az1 + az3; + const int btmp1 = MULTIPLY(atmp1, FIX_2_053119869) + az2 + az4; + const int btmp2 = MULTIPLY(atmp2, FIX_3_072711026) + az2 + az3; + const int btmp3 = MULTIPLY(atmp3, FIX_1_501321110) + az1 + az4; + + int i = DESCALE_ZEROSHIFT(tmp10 + btmp3, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 0] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp10 - btmp3, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 7] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp11 + btmp2, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 1] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp11 - btmp2, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 6] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp12 + btmp1, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 2] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp12 - btmp1, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 5] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp13 + btmp0, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 3] = (uint8)CLAMP(i); + + i = DESCALE_ZEROSHIFT(tmp13 - btmp0, CONST_BITS + PASS1_BITS + 3); + pDst_ptr[8 * 4] = (uint8)CLAMP(i); + } + }; + + template <> + struct Col<1> + { + static void idct(uint8* pDst_ptr, const int* pTemp) + { + int dcval = DESCALE_ZEROSHIFT(pTemp[0], PASS1_BITS + 3); + const uint8 dcval_clamped = (uint8)CLAMP(dcval); + pDst_ptr[0 * 8] = dcval_clamped; + pDst_ptr[1 * 8] = dcval_clamped; + pDst_ptr[2 * 8] = dcval_clamped; + pDst_ptr[3 * 8] = dcval_clamped; + pDst_ptr[4 * 8] = dcval_clamped; + pDst_ptr[5 * 8] = dcval_clamped; + pDst_ptr[6 * 8] = dcval_clamped; + pDst_ptr[7 * 8] = dcval_clamped; + } + }; + + static const uint8 s_idct_row_table[] = + { + 1,0,0,0,0,0,0,0, 2,0,0,0,0,0,0,0, 2,1,0,0,0,0,0,0, 2,1,1,0,0,0,0,0, 2,2,1,0,0,0,0,0, 3,2,1,0,0,0,0,0, 4,2,1,0,0,0,0,0, 4,3,1,0,0,0,0,0, + 4,3,2,0,0,0,0,0, 4,3,2,1,0,0,0,0, 4,3,2,1,1,0,0,0, 4,3,2,2,1,0,0,0, 4,3,3,2,1,0,0,0, 4,4,3,2,1,0,0,0, 5,4,3,2,1,0,0,0, 6,4,3,2,1,0,0,0, + 6,5,3,2,1,0,0,0, 6,5,4,2,1,0,0,0, 6,5,4,3,1,0,0,0, 6,5,4,3,2,0,0,0, 6,5,4,3,2,1,0,0, 6,5,4,3,2,1,1,0, 6,5,4,3,2,2,1,0, 6,5,4,3,3,2,1,0, + 6,5,4,4,3,2,1,0, 6,5,5,4,3,2,1,0, 6,6,5,4,3,2,1,0, 7,6,5,4,3,2,1,0, 8,6,5,4,3,2,1,0, 8,7,5,4,3,2,1,0, 8,7,6,4,3,2,1,0, 8,7,6,5,3,2,1,0, + 8,7,6,5,4,2,1,0, 8,7,6,5,4,3,1,0, 8,7,6,5,4,3,2,0, 8,7,6,5,4,3,2,1, 8,7,6,5,4,3,2,2, 8,7,6,5,4,3,3,2, 8,7,6,5,4,4,3,2, 8,7,6,5,5,4,3,2, + 8,7,6,6,5,4,3,2, 8,7,7,6,5,4,3,2, 8,8,7,6,5,4,3,2, 8,8,8,6,5,4,3,2, 8,8,8,7,5,4,3,2, 8,8,8,7,6,4,3,2, 8,8,8,7,6,5,3,2, 8,8,8,7,6,5,4,2, + 8,8,8,7,6,5,4,3, 8,8,8,7,6,5,4,4, 8,8,8,7,6,5,5,4, 8,8,8,7,6,6,5,4, 8,8,8,7,7,6,5,4, 8,8,8,8,7,6,5,4, 8,8,8,8,8,6,5,4, 8,8,8,8,8,7,5,4, + 8,8,8,8,8,7,6,4, 8,8,8,8,8,7,6,5, 8,8,8,8,8,7,6,6, 8,8,8,8,8,7,7,6, 8,8,8,8,8,8,7,6, 8,8,8,8,8,8,8,6, 8,8,8,8,8,8,8,7, 8,8,8,8,8,8,8,8, + }; + + static const uint8 s_idct_col_table[] = + { + 1, 1, 2, 3, 3, 3, 3, 3, 3, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 + }; + + // Scalar "fast pathing" IDCT. + static void idct(const jpgd_block_coeff_t* pSrc_ptr, uint8* pDst_ptr, int block_max_zag, bool use_simd) + { + (void)use_simd; + + assert(block_max_zag >= 1); + assert(block_max_zag <= 64); + + if (block_max_zag <= 1) + { + int k = ((pSrc_ptr[0] + 4) >> 3) + 128; + k = CLAMP(k); + k = k | (k << 8); + k = k | (k << 16); + + for (int i = 8; i > 0; i--) + { + *(int*)&pDst_ptr[0] = k; + *(int*)&pDst_ptr[4] = k; + pDst_ptr += 8; + } + return; + } + +#if JPGD_USE_SSE2 + if (use_simd) + { + assert((((uintptr_t)pSrc_ptr) & 15) == 0); + assert((((uintptr_t)pDst_ptr) & 15) == 0); + idctSSEShortU8(pSrc_ptr, pDst_ptr); + return; + } #endif - } -}; - -template <> -struct Row<1> -{ - static void idct(int* pTemp, const jpgd_block_t* pSrc) - { - const int dcval = (pSrc[0] << PASS1_BITS); - - pTemp[0] = dcval; - pTemp[1] = dcval; - pTemp[2] = dcval; - pTemp[3] = dcval; - pTemp[4] = dcval; - pTemp[5] = dcval; - pTemp[6] = dcval; - pTemp[7] = dcval; - } -}; - -// Compiler creates a fast path 1D IDCT for X non-zero rows -template <int NONZERO_ROWS> -struct Col -{ - static void idct(uint8* pDst_ptr, const int* pTemp) - { - // ACCESS_ROW() will be optimized at compile time to either an array access, or 0. - #define ACCESS_ROW(x) (((x) < NONZERO_ROWS) ? pTemp[x * 8] : 0) - - const int z2 = ACCESS_ROW(2); - const int z3 = ACCESS_ROW(6); - - const int z1 = MULTIPLY(z2 + z3, FIX_0_541196100); - const int tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065); - const int tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); - - const int tmp0 = (ACCESS_ROW(0) + ACCESS_ROW(4)) << CONST_BITS; - const int tmp1 = (ACCESS_ROW(0) - ACCESS_ROW(4)) << CONST_BITS; - - const int tmp10 = tmp0 + tmp3, tmp13 = tmp0 - tmp3, tmp11 = tmp1 + tmp2, tmp12 = tmp1 - tmp2; - - const int atmp0 = ACCESS_ROW(7), atmp1 = ACCESS_ROW(5), atmp2 = ACCESS_ROW(3), atmp3 = ACCESS_ROW(1); - - const int bz1 = atmp0 + atmp3, bz2 = atmp1 + atmp2, bz3 = atmp0 + atmp2, bz4 = atmp1 + atmp3; - const int bz5 = MULTIPLY(bz3 + bz4, FIX_1_175875602); - - const int az1 = MULTIPLY(bz1, - FIX_0_899976223); - const int az2 = MULTIPLY(bz2, - FIX_2_562915447); - const int az3 = MULTIPLY(bz3, - FIX_1_961570560) + bz5; - const int az4 = MULTIPLY(bz4, - FIX_0_390180644) + bz5; - - const int btmp0 = MULTIPLY(atmp0, FIX_0_298631336) + az1 + az3; - const int btmp1 = MULTIPLY(atmp1, FIX_2_053119869) + az2 + az4; - const int btmp2 = MULTIPLY(atmp2, FIX_3_072711026) + az2 + az3; - const int btmp3 = MULTIPLY(atmp3, FIX_1_501321110) + az1 + az4; - - int i = DESCALE_ZEROSHIFT(tmp10 + btmp3, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*0] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp10 - btmp3, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*7] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp11 + btmp2, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*1] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp11 - btmp2, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*6] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp12 + btmp1, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*2] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp12 - btmp1, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*5] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp13 + btmp0, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*3] = (uint8)CLAMP(i); - - i = DESCALE_ZEROSHIFT(tmp13 - btmp0, CONST_BITS+PASS1_BITS+3); - pDst_ptr[8*4] = (uint8)CLAMP(i); - } -}; - -template <> -struct Col<1> -{ - static void idct(uint8* pDst_ptr, const int* pTemp) - { - int dcval = DESCALE_ZEROSHIFT(pTemp[0], PASS1_BITS+3); - const uint8 dcval_clamped = (uint8)CLAMP(dcval); - pDst_ptr[0*8] = dcval_clamped; - pDst_ptr[1*8] = dcval_clamped; - pDst_ptr[2*8] = dcval_clamped; - pDst_ptr[3*8] = dcval_clamped; - pDst_ptr[4*8] = dcval_clamped; - pDst_ptr[5*8] = dcval_clamped; - pDst_ptr[6*8] = dcval_clamped; - pDst_ptr[7*8] = dcval_clamped; - } -}; - -static const uint8 s_idct_row_table[] = -{ - 1,0,0,0,0,0,0,0, 2,0,0,0,0,0,0,0, 2,1,0,0,0,0,0,0, 2,1,1,0,0,0,0,0, 2,2,1,0,0,0,0,0, 3,2,1,0,0,0,0,0, 4,2,1,0,0,0,0,0, 4,3,1,0,0,0,0,0, - 4,3,2,0,0,0,0,0, 4,3,2,1,0,0,0,0, 4,3,2,1,1,0,0,0, 4,3,2,2,1,0,0,0, 4,3,3,2,1,0,0,0, 4,4,3,2,1,0,0,0, 5,4,3,2,1,0,0,0, 6,4,3,2,1,0,0,0, - 6,5,3,2,1,0,0,0, 6,5,4,2,1,0,0,0, 6,5,4,3,1,0,0,0, 6,5,4,3,2,0,0,0, 6,5,4,3,2,1,0,0, 6,5,4,3,2,1,1,0, 6,5,4,3,2,2,1,0, 6,5,4,3,3,2,1,0, - 6,5,4,4,3,2,1,0, 6,5,5,4,3,2,1,0, 6,6,5,4,3,2,1,0, 7,6,5,4,3,2,1,0, 8,6,5,4,3,2,1,0, 8,7,5,4,3,2,1,0, 8,7,6,4,3,2,1,0, 8,7,6,5,3,2,1,0, - 8,7,6,5,4,2,1,0, 8,7,6,5,4,3,1,0, 8,7,6,5,4,3,2,0, 8,7,6,5,4,3,2,1, 8,7,6,5,4,3,2,2, 8,7,6,5,4,3,3,2, 8,7,6,5,4,4,3,2, 8,7,6,5,5,4,3,2, - 8,7,6,6,5,4,3,2, 8,7,7,6,5,4,3,2, 8,8,7,6,5,4,3,2, 8,8,8,6,5,4,3,2, 8,8,8,7,5,4,3,2, 8,8,8,7,6,4,3,2, 8,8,8,7,6,5,3,2, 8,8,8,7,6,5,4,2, - 8,8,8,7,6,5,4,3, 8,8,8,7,6,5,4,4, 8,8,8,7,6,5,5,4, 8,8,8,7,6,6,5,4, 8,8,8,7,7,6,5,4, 8,8,8,8,7,6,5,4, 8,8,8,8,8,6,5,4, 8,8,8,8,8,7,5,4, - 8,8,8,8,8,7,6,4, 8,8,8,8,8,7,6,5, 8,8,8,8,8,7,6,6, 8,8,8,8,8,7,7,6, 8,8,8,8,8,8,7,6, 8,8,8,8,8,8,8,6, 8,8,8,8,8,8,8,7, 8,8,8,8,8,8,8,8, -}; - -static const uint8 s_idct_col_table[] = { 1, 1, 2, 3, 3, 3, 3, 3, 3, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 }; - -void idct(const jpgd_block_t* pSrc_ptr, uint8* pDst_ptr, int block_max_zag) -{ - JPGD_ASSERT(block_max_zag >= 1); - JPGD_ASSERT(block_max_zag <= 64); - - if (block_max_zag <= 1) - { - int k = ((pSrc_ptr[0] + 4) >> 3) + 128; - k = CLAMP(k); - k = k | (k<<8); - k = k | (k<<16); - - for (int i = 8; i > 0; i--) - { - *(int*)&pDst_ptr[0] = k; - *(int*)&pDst_ptr[4] = k; - pDst_ptr += 8; - } - return; - } - - int temp[64]; - - const jpgd_block_t* pSrc = pSrc_ptr; - int* pTemp = temp; - - const uint8* pRow_tab = &s_idct_row_table[(block_max_zag - 1) * 8]; - int i; - for (i = 8; i > 0; i--, pRow_tab++) - { - switch (*pRow_tab) - { - case 0: Row<0>::idct(pTemp, pSrc); break; - case 1: Row<1>::idct(pTemp, pSrc); break; - case 2: Row<2>::idct(pTemp, pSrc); break; - case 3: Row<3>::idct(pTemp, pSrc); break; - case 4: Row<4>::idct(pTemp, pSrc); break; - case 5: Row<5>::idct(pTemp, pSrc); break; - case 6: Row<6>::idct(pTemp, pSrc); break; - case 7: Row<7>::idct(pTemp, pSrc); break; - case 8: Row<8>::idct(pTemp, pSrc); break; - } - - pSrc += 8; - pTemp += 8; - } - - pTemp = temp; - - const int nonzero_rows = s_idct_col_table[block_max_zag - 1]; - for (i = 8; i > 0; i--) - { - switch (nonzero_rows) - { - case 1: Col<1>::idct(pDst_ptr, pTemp); break; - case 2: Col<2>::idct(pDst_ptr, pTemp); break; - case 3: Col<3>::idct(pDst_ptr, pTemp); break; - case 4: Col<4>::idct(pDst_ptr, pTemp); break; - case 5: Col<5>::idct(pDst_ptr, pTemp); break; - case 6: Col<6>::idct(pDst_ptr, pTemp); break; - case 7: Col<7>::idct(pDst_ptr, pTemp); break; - case 8: Col<8>::idct(pDst_ptr, pTemp); break; - } - - pTemp++; - pDst_ptr++; - } -} - -void idct_4x4(const jpgd_block_t* pSrc_ptr, uint8* pDst_ptr) -{ - int temp[64]; - int* pTemp = temp; - const jpgd_block_t* pSrc = pSrc_ptr; - - for (int i = 4; i > 0; i--) - { - Row<4>::idct(pTemp, pSrc); - pSrc += 8; - pTemp += 8; - } - - pTemp = temp; - for (int i = 8; i > 0; i--) - { - Col<4>::idct(pDst_ptr, pTemp); - pTemp++; - pDst_ptr++; - } -} - -// Retrieve one character from the input stream. -inline uint jpeg_decoder::get_char() -{ - // Any bytes remaining in buffer? - if (!m_in_buf_left) - { - // Try to get more bytes. - prep_in_buffer(); - // Still nothing to get? - if (!m_in_buf_left) - { - // Pad the end of the stream with 0xFF 0xD9 (EOI marker) - int t = m_tem_flag; - m_tem_flag ^= 1; - if (t) - return 0xD9; - else - return 0xFF; - } - } - - uint c = *m_pIn_buf_ofs++; - m_in_buf_left--; - - return c; -} - -// Same as previous method, except can indicate if the character is a pad character or not. -inline uint jpeg_decoder::get_char(bool *pPadding_flag) -{ - if (!m_in_buf_left) - { - prep_in_buffer(); - if (!m_in_buf_left) - { - *pPadding_flag = true; - int t = m_tem_flag; - m_tem_flag ^= 1; - if (t) - return 0xD9; - else - return 0xFF; - } - } - - *pPadding_flag = false; - - uint c = *m_pIn_buf_ofs++; - m_in_buf_left--; - - return c; -} - -// Inserts a previously retrieved character back into the input buffer. -inline void jpeg_decoder::stuff_char(uint8 q) -{ - *(--m_pIn_buf_ofs) = q; - m_in_buf_left++; -} - -// Retrieves one character from the input stream, but does not read past markers. Will continue to return 0xFF when a marker is encountered. -inline uint8 jpeg_decoder::get_octet() -{ - bool padding_flag; - int c = get_char(&padding_flag); - - if (c == 0xFF) - { - if (padding_flag) - return 0xFF; - - c = get_char(&padding_flag); - if (padding_flag) - { - stuff_char(0xFF); - return 0xFF; - } - - if (c == 0x00) - return 0xFF; - else - { - stuff_char(static_cast<uint8>(c)); - stuff_char(0xFF); - return 0xFF; - } - } - - return static_cast<uint8>(c); -} - -// Retrieves a variable number of bits from the input stream. Does not recognize markers. -inline uint jpeg_decoder::get_bits(int num_bits) -{ - if (!num_bits) - return 0; - - uint i = m_bit_buf >> (32 - num_bits); - - if ((m_bits_left -= num_bits) <= 0) - { - m_bit_buf <<= (num_bits += m_bits_left); - - uint c1 = get_char(); - uint c2 = get_char(); - m_bit_buf = (m_bit_buf & 0xFFFF0000) | (c1 << 8) | c2; - - m_bit_buf <<= -m_bits_left; - - m_bits_left += 16; - - JPGD_ASSERT(m_bits_left >= 0); - } - else - m_bit_buf <<= num_bits; - - return i; -} - -// Retrieves a variable number of bits from the input stream. Markers will not be read into the input bit buffer. Instead, an infinite number of all 1's will be returned when a marker is encountered. -inline uint jpeg_decoder::get_bits_no_markers(int num_bits) -{ - if (!num_bits) - return 0; - - uint i = m_bit_buf >> (32 - num_bits); - - if ((m_bits_left -= num_bits) <= 0) - { - m_bit_buf <<= (num_bits += m_bits_left); - - if ((m_in_buf_left < 2) || (m_pIn_buf_ofs[0] == 0xFF) || (m_pIn_buf_ofs[1] == 0xFF)) - { - uint c1 = get_octet(); - uint c2 = get_octet(); - m_bit_buf |= (c1 << 8) | c2; - } - else - { - m_bit_buf |= ((uint)m_pIn_buf_ofs[0] << 8) | m_pIn_buf_ofs[1]; - m_in_buf_left -= 2; - m_pIn_buf_ofs += 2; - } - - m_bit_buf <<= -m_bits_left; - - m_bits_left += 16; - - JPGD_ASSERT(m_bits_left >= 0); - } - else - m_bit_buf <<= num_bits; - - return i; -} - -// Decodes a Huffman encoded symbol. -inline int jpeg_decoder::huff_decode(huff_tables *pH) -{ - JPGD_ASSERT(pH); - - int symbol; - // Check first 8-bits: do we have a complete symbol? - if ((symbol = pH->look_up[m_bit_buf >> 24]) < 0) - { - // Decode more bits, use a tree traversal to find symbol. - int ofs = 23; - do - { - unsigned int idx = -(int)(symbol + ((m_bit_buf >> ofs) & 1)); - JPGD_ASSERT(idx < JPGD_HUFF_TREE_MAX_LENGTH); - symbol = pH->tree[idx]; - ofs--; - } while (symbol < 0); - - get_bits_no_markers(8 + (23 - ofs)); - } - else - { - JPGD_ASSERT(symbol < JPGD_HUFF_CODE_SIZE_MAX_LENGTH); - get_bits_no_markers(pH->code_size[symbol]); - } - - return symbol; -} - -// Decodes a Huffman encoded symbol. -inline int jpeg_decoder::huff_decode(huff_tables *pH, int& extra_bits) -{ - int symbol; - - JPGD_ASSERT(pH); - - // Check first 8-bits: do we have a complete symbol? - if ((symbol = pH->look_up2[m_bit_buf >> 24]) < 0) - { - // Use a tree traversal to find symbol. - int ofs = 23; - do - { - unsigned int idx = -(int)(symbol + ((m_bit_buf >> ofs) & 1)); - JPGD_ASSERT(idx < JPGD_HUFF_TREE_MAX_LENGTH); - symbol = pH->tree[idx]; - ofs--; - } while (symbol < 0); - - get_bits_no_markers(8 + (23 - ofs)); - - extra_bits = get_bits_no_markers(symbol & 0xF); - } - else - { - JPGD_ASSERT(((symbol >> 8) & 31) == pH->code_size[symbol & 255] + ((symbol & 0x8000) ? (symbol & 15) : 0)); - - if (symbol & 0x8000) - { - get_bits_no_markers((symbol >> 8) & 31); - extra_bits = symbol >> 16; - } - else - { - int code_size = (symbol >> 8) & 31; - int num_extra_bits = symbol & 0xF; - int bits = code_size + num_extra_bits; - if (bits <= (m_bits_left + 16)) - extra_bits = get_bits_no_markers(bits) & ((1 << num_extra_bits) - 1); - else - { - get_bits_no_markers(code_size); - extra_bits = get_bits_no_markers(num_extra_bits); - } - } - - symbol &= 0xFF; - } - - return symbol; -} - -// Tables and macro used to fully decode the DPCM differences. -static const int s_extend_test[16] = { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 }; -static const int s_extend_offset[16] = { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1, ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1, ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1, ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 }; -static const int s_extend_mask[] = { 0, (1<<0), (1<<1), (1<<2), (1<<3), (1<<4), (1<<5), (1<<6), (1<<7), (1<<8), (1<<9), (1<<10), (1<<11), (1<<12), (1<<13), (1<<14), (1<<15), (1<<16) }; -// The logical AND's in this macro are to shut up static code analysis (aren't really necessary - couldn't find another way to do this) + + int temp[64]; + + const jpgd_block_coeff_t* pSrc = pSrc_ptr; + int* pTemp = temp; + + const uint8* pRow_tab = &s_idct_row_table[(block_max_zag - 1) * 8]; + int i; + for (i = 8; i > 0; i--, pRow_tab++) + { + switch (*pRow_tab) + { + case 0: Row<0>::idct(pTemp, pSrc); break; + case 1: Row<1>::idct(pTemp, pSrc); break; + case 2: Row<2>::idct(pTemp, pSrc); break; + case 3: Row<3>::idct(pTemp, pSrc); break; + case 4: Row<4>::idct(pTemp, pSrc); break; + case 5: Row<5>::idct(pTemp, pSrc); break; + case 6: Row<6>::idct(pTemp, pSrc); break; + case 7: Row<7>::idct(pTemp, pSrc); break; + case 8: Row<8>::idct(pTemp, pSrc); break; + } + + pSrc += 8; + pTemp += 8; + } + + pTemp = temp; + + const int nonzero_rows = s_idct_col_table[block_max_zag - 1]; + for (i = 8; i > 0; i--) + { + switch (nonzero_rows) + { + case 1: Col<1>::idct(pDst_ptr, pTemp); break; + case 2: Col<2>::idct(pDst_ptr, pTemp); break; + case 3: Col<3>::idct(pDst_ptr, pTemp); break; + case 4: Col<4>::idct(pDst_ptr, pTemp); break; + case 5: Col<5>::idct(pDst_ptr, pTemp); break; + case 6: Col<6>::idct(pDst_ptr, pTemp); break; + case 7: Col<7>::idct(pDst_ptr, pTemp); break; + case 8: Col<8>::idct(pDst_ptr, pTemp); break; + } + + pTemp++; + pDst_ptr++; + } + } + + // Retrieve one character from the input stream. + inline uint jpeg_decoder::get_char() + { + // Any bytes remaining in buffer? + if (!m_in_buf_left) + { + // Try to get more bytes. + prep_in_buffer(); + // Still nothing to get? + if (!m_in_buf_left) + { + // Pad the end of the stream with 0xFF 0xD9 (EOI marker) + int t = m_tem_flag; + m_tem_flag ^= 1; + if (t) + return 0xD9; + else + return 0xFF; + } + } + + uint c = *m_pIn_buf_ofs++; + m_in_buf_left--; + + return c; + } + + // Same as previous method, except can indicate if the character is a pad character or not. + inline uint jpeg_decoder::get_char(bool* pPadding_flag) + { + if (!m_in_buf_left) + { + prep_in_buffer(); + if (!m_in_buf_left) + { + *pPadding_flag = true; + int t = m_tem_flag; + m_tem_flag ^= 1; + if (t) + return 0xD9; + else + return 0xFF; + } + } + + *pPadding_flag = false; + + uint c = *m_pIn_buf_ofs++; + m_in_buf_left--; + + return c; + } + + // Inserts a previously retrieved character back into the input buffer. + inline void jpeg_decoder::stuff_char(uint8 q) + { + // This could write before the input buffer, but we've placed another array there. + *(--m_pIn_buf_ofs) = q; + m_in_buf_left++; + } + + // Retrieves one character from the input stream, but does not read past markers. Will continue to return 0xFF when a marker is encountered. + inline uint8 jpeg_decoder::get_octet() + { + bool padding_flag; + int c = get_char(&padding_flag); + + if (c == 0xFF) + { + if (padding_flag) + return 0xFF; + + c = get_char(&padding_flag); + if (padding_flag) + { + stuff_char(0xFF); + return 0xFF; + } + + if (c == 0x00) + return 0xFF; + else + { + stuff_char(static_cast<uint8>(c)); + stuff_char(0xFF); + return 0xFF; + } + } + + return static_cast<uint8>(c); + } + + // Retrieves a variable number of bits from the input stream. Does not recognize markers. + inline uint jpeg_decoder::get_bits(int num_bits) + { + if (!num_bits) + return 0; + + uint i = m_bit_buf >> (32 - num_bits); + + if ((m_bits_left -= num_bits) <= 0) + { + m_bit_buf <<= (num_bits += m_bits_left); + + uint c1 = get_char(); + uint c2 = get_char(); + m_bit_buf = (m_bit_buf & 0xFFFF0000) | (c1 << 8) | c2; + + m_bit_buf <<= -m_bits_left; + + m_bits_left += 16; + + assert(m_bits_left >= 0); + } + else + m_bit_buf <<= num_bits; + + return i; + } + + // Retrieves a variable number of bits from the input stream. Markers will not be read into the input bit buffer. Instead, an infinite number of all 1's will be returned when a marker is encountered. + inline uint jpeg_decoder::get_bits_no_markers(int num_bits) + { + if (!num_bits) + return 0; + + assert(num_bits <= 16); + + uint i = m_bit_buf >> (32 - num_bits); + + if ((m_bits_left -= num_bits) <= 0) + { + m_bit_buf <<= (num_bits += m_bits_left); + + if ((m_in_buf_left < 2) || (m_pIn_buf_ofs[0] == 0xFF) || (m_pIn_buf_ofs[1] == 0xFF)) + { + uint c1 = get_octet(); + uint c2 = get_octet(); + m_bit_buf |= (c1 << 8) | c2; + } + else + { + m_bit_buf |= ((uint)m_pIn_buf_ofs[0] << 8) | m_pIn_buf_ofs[1]; + m_in_buf_left -= 2; + m_pIn_buf_ofs += 2; + } + + m_bit_buf <<= -m_bits_left; + + m_bits_left += 16; + + assert(m_bits_left >= 0); + } + else + m_bit_buf <<= num_bits; + + return i; + } + + // Decodes a Huffman encoded symbol. + inline int jpeg_decoder::huff_decode(huff_tables* pH) + { + if (!pH) + stop_decoding(JPGD_DECODE_ERROR); + + int symbol; + // Check first 8-bits: do we have a complete symbol? + if ((symbol = pH->look_up[m_bit_buf >> 24]) < 0) + { + // Decode more bits, use a tree traversal to find symbol. + int ofs = 23; + do + { + unsigned int idx = -(int)(symbol + ((m_bit_buf >> ofs) & 1)); + + // This should never happen, but to be safe I'm turning these asserts into a run-time check. + if ((idx >= JPGD_HUFF_TREE_MAX_LENGTH) || (ofs < 0)) + stop_decoding(JPGD_DECODE_ERROR); + + symbol = pH->tree[idx]; + ofs--; + } while (symbol < 0); + + get_bits_no_markers(8 + (23 - ofs)); + } + else + { + assert(symbol < JPGD_HUFF_CODE_SIZE_MAX_LENGTH); + get_bits_no_markers(pH->code_size[symbol]); + } + + return symbol; + } + + // Decodes a Huffman encoded symbol. + inline int jpeg_decoder::huff_decode(huff_tables* pH, int& extra_bits) + { + int symbol; + + if (!pH) + stop_decoding(JPGD_DECODE_ERROR); + + // Check first 8-bits: do we have a complete symbol? + if ((symbol = pH->look_up2[m_bit_buf >> 24]) < 0) + { + // Use a tree traversal to find symbol. + int ofs = 23; + do + { + unsigned int idx = -(int)(symbol + ((m_bit_buf >> ofs) & 1)); + + // This should never happen, but to be safe I'm turning these asserts into a run-time check. + if ((idx >= JPGD_HUFF_TREE_MAX_LENGTH) || (ofs < 0)) + stop_decoding(JPGD_DECODE_ERROR); + + symbol = pH->tree[idx]; + ofs--; + } while (symbol < 0); + + get_bits_no_markers(8 + (23 - ofs)); + + extra_bits = get_bits_no_markers(symbol & 0xF); + } + else + { + if (symbol & 0x8000) + { + //get_bits_no_markers((symbol >> 8) & 31); + assert(((symbol >> 8) & 31) <= 15); + get_bits_no_markers((symbol >> 8) & 15); + extra_bits = symbol >> 16; + } + else + { + int code_size = (symbol >> 8) & 31; + int num_extra_bits = symbol & 0xF; + int bits = code_size + num_extra_bits; + + if (bits <= 16) + extra_bits = get_bits_no_markers(bits) & ((1 << num_extra_bits) - 1); + else + { + get_bits_no_markers(code_size); + extra_bits = get_bits_no_markers(num_extra_bits); + } + } + + symbol &= 0xFF; + } + + return symbol; + } + + // Tables and macro used to fully decode the DPCM differences. + static const int s_extend_test[16] = { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 }; + static const int s_extend_offset[16] = { 0, -1, -3, -7, -15, -31, -63, -127, -255, -511, -1023, -2047, -4095, -8191, -16383, -32767 }; + //static const int s_extend_mask[] = { 0, (1 << 0), (1 << 1), (1 << 2), (1 << 3), (1 << 4), (1 << 5), (1 << 6), (1 << 7), (1 << 8), (1 << 9), (1 << 10), (1 << 11), (1 << 12), (1 << 13), (1 << 14), (1 << 15), (1 << 16) }; + #define JPGD_HUFF_EXTEND(x, s) (((x) < s_extend_test[s & 15]) ? ((x) + s_extend_offset[s & 15]) : (x)) -// Clamps a value between 0-255. -inline uint8 jpeg_decoder::clamp(int i) -{ - if (static_cast<uint>(i) > 255) - i = (((~i) >> 31) & 0xFF); - - return static_cast<uint8>(i); -} - -namespace DCT_Upsample -{ - struct Matrix44 - { - typedef int Element_Type; - enum { NUM_ROWS = 4, NUM_COLS = 4 }; - - Element_Type v[NUM_ROWS][NUM_COLS]; - - inline int rows() const { return NUM_ROWS; } - inline int cols() const { return NUM_COLS; } - - inline const Element_Type & at(int r, int c) const { return v[r][c]; } - inline Element_Type & at(int r, int c) { return v[r][c]; } - - inline Matrix44() { } - - inline Matrix44& operator += (const Matrix44& a) - { - for (int r = 0; r < NUM_ROWS; r++) - { - at(r, 0) += a.at(r, 0); - at(r, 1) += a.at(r, 1); - at(r, 2) += a.at(r, 2); - at(r, 3) += a.at(r, 3); - } - return *this; - } - - inline Matrix44& operator -= (const Matrix44& a) - { - for (int r = 0; r < NUM_ROWS; r++) - { - at(r, 0) -= a.at(r, 0); - at(r, 1) -= a.at(r, 1); - at(r, 2) -= a.at(r, 2); - at(r, 3) -= a.at(r, 3); - } - return *this; - } - - friend inline Matrix44 operator + (const Matrix44& a, const Matrix44& b) - { - Matrix44 ret; - for (int r = 0; r < NUM_ROWS; r++) - { - ret.at(r, 0) = a.at(r, 0) + b.at(r, 0); - ret.at(r, 1) = a.at(r, 1) + b.at(r, 1); - ret.at(r, 2) = a.at(r, 2) + b.at(r, 2); - ret.at(r, 3) = a.at(r, 3) + b.at(r, 3); - } - return ret; - } - - friend inline Matrix44 operator - (const Matrix44& a, const Matrix44& b) - { - Matrix44 ret; - for (int r = 0; r < NUM_ROWS; r++) - { - ret.at(r, 0) = a.at(r, 0) - b.at(r, 0); - ret.at(r, 1) = a.at(r, 1) - b.at(r, 1); - ret.at(r, 2) = a.at(r, 2) - b.at(r, 2); - ret.at(r, 3) = a.at(r, 3) - b.at(r, 3); - } - return ret; - } - - static inline void add_and_store(jpgd_block_t* pDst, const Matrix44& a, const Matrix44& b) - { - for (int r = 0; r < 4; r++) - { - pDst[0*8 + r] = static_cast<jpgd_block_t>(a.at(r, 0) + b.at(r, 0)); - pDst[1*8 + r] = static_cast<jpgd_block_t>(a.at(r, 1) + b.at(r, 1)); - pDst[2*8 + r] = static_cast<jpgd_block_t>(a.at(r, 2) + b.at(r, 2)); - pDst[3*8 + r] = static_cast<jpgd_block_t>(a.at(r, 3) + b.at(r, 3)); - } - } - - static inline void sub_and_store(jpgd_block_t* pDst, const Matrix44& a, const Matrix44& b) - { - for (int r = 0; r < 4; r++) - { - pDst[0*8 + r] = static_cast<jpgd_block_t>(a.at(r, 0) - b.at(r, 0)); - pDst[1*8 + r] = static_cast<jpgd_block_t>(a.at(r, 1) - b.at(r, 1)); - pDst[2*8 + r] = static_cast<jpgd_block_t>(a.at(r, 2) - b.at(r, 2)); - pDst[3*8 + r] = static_cast<jpgd_block_t>(a.at(r, 3) - b.at(r, 3)); - } - } - }; - - const int FRACT_BITS = 10; - const int SCALE = 1 << FRACT_BITS; - - typedef int Temp_Type; - #define D(i) (((i) + (SCALE >> 1)) >> FRACT_BITS) - #define F(i) ((int)((i) * SCALE + .5f)) - - // Any decent C++ compiler will optimize this at compile time to a 0, or an array access. - #define AT(c, r) ((((c)>=NUM_COLS)||((r)>=NUM_ROWS)) ? 0 : pSrc[(c)+(r)*8]) - - // NUM_ROWS/NUM_COLS = # of non-zero rows/cols in input matrix - template<int NUM_ROWS, int NUM_COLS> - struct P_Q - { - static void calc(Matrix44& P, Matrix44& Q, const jpgd_block_t* pSrc) - { - // 4x8 = 4x8 times 8x8, matrix 0 is constant - const Temp_Type X000 = AT(0, 0); - const Temp_Type X001 = AT(0, 1); - const Temp_Type X002 = AT(0, 2); - const Temp_Type X003 = AT(0, 3); - const Temp_Type X004 = AT(0, 4); - const Temp_Type X005 = AT(0, 5); - const Temp_Type X006 = AT(0, 6); - const Temp_Type X007 = AT(0, 7); - const Temp_Type X010 = D(F(0.415735f) * AT(1, 0) + F(0.791065f) * AT(3, 0) + F(-0.352443f) * AT(5, 0) + F(0.277785f) * AT(7, 0)); - const Temp_Type X011 = D(F(0.415735f) * AT(1, 1) + F(0.791065f) * AT(3, 1) + F(-0.352443f) * AT(5, 1) + F(0.277785f) * AT(7, 1)); - const Temp_Type X012 = D(F(0.415735f) * AT(1, 2) + F(0.791065f) * AT(3, 2) + F(-0.352443f) * AT(5, 2) + F(0.277785f) * AT(7, 2)); - const Temp_Type X013 = D(F(0.415735f) * AT(1, 3) + F(0.791065f) * AT(3, 3) + F(-0.352443f) * AT(5, 3) + F(0.277785f) * AT(7, 3)); - const Temp_Type X014 = D(F(0.415735f) * AT(1, 4) + F(0.791065f) * AT(3, 4) + F(-0.352443f) * AT(5, 4) + F(0.277785f) * AT(7, 4)); - const Temp_Type X015 = D(F(0.415735f) * AT(1, 5) + F(0.791065f) * AT(3, 5) + F(-0.352443f) * AT(5, 5) + F(0.277785f) * AT(7, 5)); - const Temp_Type X016 = D(F(0.415735f) * AT(1, 6) + F(0.791065f) * AT(3, 6) + F(-0.352443f) * AT(5, 6) + F(0.277785f) * AT(7, 6)); - const Temp_Type X017 = D(F(0.415735f) * AT(1, 7) + F(0.791065f) * AT(3, 7) + F(-0.352443f) * AT(5, 7) + F(0.277785f) * AT(7, 7)); - const Temp_Type X020 = AT(4, 0); - const Temp_Type X021 = AT(4, 1); - const Temp_Type X022 = AT(4, 2); - const Temp_Type X023 = AT(4, 3); - const Temp_Type X024 = AT(4, 4); - const Temp_Type X025 = AT(4, 5); - const Temp_Type X026 = AT(4, 6); - const Temp_Type X027 = AT(4, 7); - const Temp_Type X030 = D(F(0.022887f) * AT(1, 0) + F(-0.097545f) * AT(3, 0) + F(0.490393f) * AT(5, 0) + F(0.865723f) * AT(7, 0)); - const Temp_Type X031 = D(F(0.022887f) * AT(1, 1) + F(-0.097545f) * AT(3, 1) + F(0.490393f) * AT(5, 1) + F(0.865723f) * AT(7, 1)); - const Temp_Type X032 = D(F(0.022887f) * AT(1, 2) + F(-0.097545f) * AT(3, 2) + F(0.490393f) * AT(5, 2) + F(0.865723f) * AT(7, 2)); - const Temp_Type X033 = D(F(0.022887f) * AT(1, 3) + F(-0.097545f) * AT(3, 3) + F(0.490393f) * AT(5, 3) + F(0.865723f) * AT(7, 3)); - const Temp_Type X034 = D(F(0.022887f) * AT(1, 4) + F(-0.097545f) * AT(3, 4) + F(0.490393f) * AT(5, 4) + F(0.865723f) * AT(7, 4)); - const Temp_Type X035 = D(F(0.022887f) * AT(1, 5) + F(-0.097545f) * AT(3, 5) + F(0.490393f) * AT(5, 5) + F(0.865723f) * AT(7, 5)); - const Temp_Type X036 = D(F(0.022887f) * AT(1, 6) + F(-0.097545f) * AT(3, 6) + F(0.490393f) * AT(5, 6) + F(0.865723f) * AT(7, 6)); - const Temp_Type X037 = D(F(0.022887f) * AT(1, 7) + F(-0.097545f) * AT(3, 7) + F(0.490393f) * AT(5, 7) + F(0.865723f) * AT(7, 7)); - - // 4x4 = 4x8 times 8x4, matrix 1 is constant - P.at(0, 0) = X000; - P.at(0, 1) = D(X001 * F(0.415735f) + X003 * F(0.791065f) + X005 * F(-0.352443f) + X007 * F(0.277785f)); - P.at(0, 2) = X004; - P.at(0, 3) = D(X001 * F(0.022887f) + X003 * F(-0.097545f) + X005 * F(0.490393f) + X007 * F(0.865723f)); - P.at(1, 0) = X010; - P.at(1, 1) = D(X011 * F(0.415735f) + X013 * F(0.791065f) + X015 * F(-0.352443f) + X017 * F(0.277785f)); - P.at(1, 2) = X014; - P.at(1, 3) = D(X011 * F(0.022887f) + X013 * F(-0.097545f) + X015 * F(0.490393f) + X017 * F(0.865723f)); - P.at(2, 0) = X020; - P.at(2, 1) = D(X021 * F(0.415735f) + X023 * F(0.791065f) + X025 * F(-0.352443f) + X027 * F(0.277785f)); - P.at(2, 2) = X024; - P.at(2, 3) = D(X021 * F(0.022887f) + X023 * F(-0.097545f) + X025 * F(0.490393f) + X027 * F(0.865723f)); - P.at(3, 0) = X030; - P.at(3, 1) = D(X031 * F(0.415735f) + X033 * F(0.791065f) + X035 * F(-0.352443f) + X037 * F(0.277785f)); - P.at(3, 2) = X034; - P.at(3, 3) = D(X031 * F(0.022887f) + X033 * F(-0.097545f) + X035 * F(0.490393f) + X037 * F(0.865723f)); - // 40 muls 24 adds - - // 4x4 = 4x8 times 8x4, matrix 1 is constant - Q.at(0, 0) = D(X001 * F(0.906127f) + X003 * F(-0.318190f) + X005 * F(0.212608f) + X007 * F(-0.180240f)); - Q.at(0, 1) = X002; - Q.at(0, 2) = D(X001 * F(-0.074658f) + X003 * F(0.513280f) + X005 * F(0.768178f) + X007 * F(-0.375330f)); - Q.at(0, 3) = X006; - Q.at(1, 0) = D(X011 * F(0.906127f) + X013 * F(-0.318190f) + X015 * F(0.212608f) + X017 * F(-0.180240f)); - Q.at(1, 1) = X012; - Q.at(1, 2) = D(X011 * F(-0.074658f) + X013 * F(0.513280f) + X015 * F(0.768178f) + X017 * F(-0.375330f)); - Q.at(1, 3) = X016; - Q.at(2, 0) = D(X021 * F(0.906127f) + X023 * F(-0.318190f) + X025 * F(0.212608f) + X027 * F(-0.180240f)); - Q.at(2, 1) = X022; - Q.at(2, 2) = D(X021 * F(-0.074658f) + X023 * F(0.513280f) + X025 * F(0.768178f) + X027 * F(-0.375330f)); - Q.at(2, 3) = X026; - Q.at(3, 0) = D(X031 * F(0.906127f) + X033 * F(-0.318190f) + X035 * F(0.212608f) + X037 * F(-0.180240f)); - Q.at(3, 1) = X032; - Q.at(3, 2) = D(X031 * F(-0.074658f) + X033 * F(0.513280f) + X035 * F(0.768178f) + X037 * F(-0.375330f)); - Q.at(3, 3) = X036; - // 40 muls 24 adds - } - }; - - template<int NUM_ROWS, int NUM_COLS> - struct R_S - { - static void calc(Matrix44& R, Matrix44& S, const jpgd_block_t* pSrc) - { - // 4x8 = 4x8 times 8x8, matrix 0 is constant - const Temp_Type X100 = D(F(0.906127f) * AT(1, 0) + F(-0.318190f) * AT(3, 0) + F(0.212608f) * AT(5, 0) + F(-0.180240f) * AT(7, 0)); - const Temp_Type X101 = D(F(0.906127f) * AT(1, 1) + F(-0.318190f) * AT(3, 1) + F(0.212608f) * AT(5, 1) + F(-0.180240f) * AT(7, 1)); - const Temp_Type X102 = D(F(0.906127f) * AT(1, 2) + F(-0.318190f) * AT(3, 2) + F(0.212608f) * AT(5, 2) + F(-0.180240f) * AT(7, 2)); - const Temp_Type X103 = D(F(0.906127f) * AT(1, 3) + F(-0.318190f) * AT(3, 3) + F(0.212608f) * AT(5, 3) + F(-0.180240f) * AT(7, 3)); - const Temp_Type X104 = D(F(0.906127f) * AT(1, 4) + F(-0.318190f) * AT(3, 4) + F(0.212608f) * AT(5, 4) + F(-0.180240f) * AT(7, 4)); - const Temp_Type X105 = D(F(0.906127f) * AT(1, 5) + F(-0.318190f) * AT(3, 5) + F(0.212608f) * AT(5, 5) + F(-0.180240f) * AT(7, 5)); - const Temp_Type X106 = D(F(0.906127f) * AT(1, 6) + F(-0.318190f) * AT(3, 6) + F(0.212608f) * AT(5, 6) + F(-0.180240f) * AT(7, 6)); - const Temp_Type X107 = D(F(0.906127f) * AT(1, 7) + F(-0.318190f) * AT(3, 7) + F(0.212608f) * AT(5, 7) + F(-0.180240f) * AT(7, 7)); - const Temp_Type X110 = AT(2, 0); - const Temp_Type X111 = AT(2, 1); - const Temp_Type X112 = AT(2, 2); - const Temp_Type X113 = AT(2, 3); - const Temp_Type X114 = AT(2, 4); - const Temp_Type X115 = AT(2, 5); - const Temp_Type X116 = AT(2, 6); - const Temp_Type X117 = AT(2, 7); - const Temp_Type X120 = D(F(-0.074658f) * AT(1, 0) + F(0.513280f) * AT(3, 0) + F(0.768178f) * AT(5, 0) + F(-0.375330f) * AT(7, 0)); - const Temp_Type X121 = D(F(-0.074658f) * AT(1, 1) + F(0.513280f) * AT(3, 1) + F(0.768178f) * AT(5, 1) + F(-0.375330f) * AT(7, 1)); - const Temp_Type X122 = D(F(-0.074658f) * AT(1, 2) + F(0.513280f) * AT(3, 2) + F(0.768178f) * AT(5, 2) + F(-0.375330f) * AT(7, 2)); - const Temp_Type X123 = D(F(-0.074658f) * AT(1, 3) + F(0.513280f) * AT(3, 3) + F(0.768178f) * AT(5, 3) + F(-0.375330f) * AT(7, 3)); - const Temp_Type X124 = D(F(-0.074658f) * AT(1, 4) + F(0.513280f) * AT(3, 4) + F(0.768178f) * AT(5, 4) + F(-0.375330f) * AT(7, 4)); - const Temp_Type X125 = D(F(-0.074658f) * AT(1, 5) + F(0.513280f) * AT(3, 5) + F(0.768178f) * AT(5, 5) + F(-0.375330f) * AT(7, 5)); - const Temp_Type X126 = D(F(-0.074658f) * AT(1, 6) + F(0.513280f) * AT(3, 6) + F(0.768178f) * AT(5, 6) + F(-0.375330f) * AT(7, 6)); - const Temp_Type X127 = D(F(-0.074658f) * AT(1, 7) + F(0.513280f) * AT(3, 7) + F(0.768178f) * AT(5, 7) + F(-0.375330f) * AT(7, 7)); - const Temp_Type X130 = AT(6, 0); - const Temp_Type X131 = AT(6, 1); - const Temp_Type X132 = AT(6, 2); - const Temp_Type X133 = AT(6, 3); - const Temp_Type X134 = AT(6, 4); - const Temp_Type X135 = AT(6, 5); - const Temp_Type X136 = AT(6, 6); - const Temp_Type X137 = AT(6, 7); - // 80 muls 48 adds - - // 4x4 = 4x8 times 8x4, matrix 1 is constant - R.at(0, 0) = X100; - R.at(0, 1) = D(X101 * F(0.415735f) + X103 * F(0.791065f) + X105 * F(-0.352443f) + X107 * F(0.277785f)); - R.at(0, 2) = X104; - R.at(0, 3) = D(X101 * F(0.022887f) + X103 * F(-0.097545f) + X105 * F(0.490393f) + X107 * F(0.865723f)); - R.at(1, 0) = X110; - R.at(1, 1) = D(X111 * F(0.415735f) + X113 * F(0.791065f) + X115 * F(-0.352443f) + X117 * F(0.277785f)); - R.at(1, 2) = X114; - R.at(1, 3) = D(X111 * F(0.022887f) + X113 * F(-0.097545f) + X115 * F(0.490393f) + X117 * F(0.865723f)); - R.at(2, 0) = X120; - R.at(2, 1) = D(X121 * F(0.415735f) + X123 * F(0.791065f) + X125 * F(-0.352443f) + X127 * F(0.277785f)); - R.at(2, 2) = X124; - R.at(2, 3) = D(X121 * F(0.022887f) + X123 * F(-0.097545f) + X125 * F(0.490393f) + X127 * F(0.865723f)); - R.at(3, 0) = X130; - R.at(3, 1) = D(X131 * F(0.415735f) + X133 * F(0.791065f) + X135 * F(-0.352443f) + X137 * F(0.277785f)); - R.at(3, 2) = X134; - R.at(3, 3) = D(X131 * F(0.022887f) + X133 * F(-0.097545f) + X135 * F(0.490393f) + X137 * F(0.865723f)); - // 40 muls 24 adds - // 4x4 = 4x8 times 8x4, matrix 1 is constant - S.at(0, 0) = D(X101 * F(0.906127f) + X103 * F(-0.318190f) + X105 * F(0.212608f) + X107 * F(-0.180240f)); - S.at(0, 1) = X102; - S.at(0, 2) = D(X101 * F(-0.074658f) + X103 * F(0.513280f) + X105 * F(0.768178f) + X107 * F(-0.375330f)); - S.at(0, 3) = X106; - S.at(1, 0) = D(X111 * F(0.906127f) + X113 * F(-0.318190f) + X115 * F(0.212608f) + X117 * F(-0.180240f)); - S.at(1, 1) = X112; - S.at(1, 2) = D(X111 * F(-0.074658f) + X113 * F(0.513280f) + X115 * F(0.768178f) + X117 * F(-0.375330f)); - S.at(1, 3) = X116; - S.at(2, 0) = D(X121 * F(0.906127f) + X123 * F(-0.318190f) + X125 * F(0.212608f) + X127 * F(-0.180240f)); - S.at(2, 1) = X122; - S.at(2, 2) = D(X121 * F(-0.074658f) + X123 * F(0.513280f) + X125 * F(0.768178f) + X127 * F(-0.375330f)); - S.at(2, 3) = X126; - S.at(3, 0) = D(X131 * F(0.906127f) + X133 * F(-0.318190f) + X135 * F(0.212608f) + X137 * F(-0.180240f)); - S.at(3, 1) = X132; - S.at(3, 2) = D(X131 * F(-0.074658f) + X133 * F(0.513280f) + X135 * F(0.768178f) + X137 * F(-0.375330f)); - S.at(3, 3) = X136; - // 40 muls 24 adds - } - }; -} // end namespace DCT_Upsample - -// Unconditionally frees all allocated m_blocks. -void jpeg_decoder::free_all_blocks() -{ - m_pStream = NULL; - for (mem_block *b = m_pMem_blocks; b; ) - { - mem_block *n = b->m_pNext; - jpgd_free(b); - b = n; - } - m_pMem_blocks = NULL; -} - -// This method handles all errors. It will never return. -// It could easily be changed to use C++ exceptions. -JPGD_NORETURN void jpeg_decoder::stop_decoding(jpgd_status status) -{ - m_error_code = status; - free_all_blocks(); - longjmp(m_jmp_state, status); -} - -void *jpeg_decoder::alloc(size_t nSize, bool zero) -{ - nSize = (JPGD_MAX(nSize, 1) + 3) & ~3; - char *rv = NULL; - for (mem_block *b = m_pMem_blocks; b; b = b->m_pNext) - { - if ((b->m_used_count + nSize) <= b->m_size) - { - rv = b->m_data + b->m_used_count; - b->m_used_count += nSize; - break; - } - } - if (!rv) - { - int capacity = JPGD_MAX(32768 - 256, (nSize + 2047) & ~2047); - mem_block *b = (mem_block*)jpgd_malloc(sizeof(mem_block) + capacity); - if (!b) { stop_decoding(JPGD_NOTENOUGHMEM); } - b->m_pNext = m_pMem_blocks; m_pMem_blocks = b; - b->m_used_count = nSize; - b->m_size = capacity; - rv = b->m_data; - } - if (zero) memset(rv, 0, nSize); - return rv; -} - -void jpeg_decoder::word_clear(void *p, uint16 c, uint n) -{ - uint8 *pD = (uint8*)p; - const uint8 l = c & 0xFF, h = (c >> 8) & 0xFF; - while (n) - { - pD[0] = l; pD[1] = h; pD += 2; - n--; - } -} - -// Refill the input buffer. -// This method will sit in a loop until (A) the buffer is full or (B) -// the stream's read() method reports and end of file condition. -void jpeg_decoder::prep_in_buffer() -{ - m_in_buf_left = 0; - m_pIn_buf_ofs = m_in_buf; - - if (m_eof_flag) - return; - - do - { - int bytes_read = m_pStream->read(m_in_buf + m_in_buf_left, JPGD_IN_BUF_SIZE - m_in_buf_left, &m_eof_flag); - if (bytes_read == -1) - stop_decoding(JPGD_STREAM_READ); - - m_in_buf_left += bytes_read; - } while ((m_in_buf_left < JPGD_IN_BUF_SIZE) && (!m_eof_flag)); - - m_total_bytes_read += m_in_buf_left; - - // Pad the end of the block with M_EOI (prevents the decompressor from going off the rails if the stream is invalid). - // (This dates way back to when this decompressor was written in C/asm, and the all-asm Huffman decoder did some fancy things to increase perf.) - word_clear(m_pIn_buf_ofs + m_in_buf_left, 0xD9FF, 64); -} - -// Read a Huffman code table. -void jpeg_decoder::read_dht_marker() -{ - int i, index, count; - uint8 huff_num[17]; - uint8 huff_val[256]; - - uint num_left = get_bits(16); - - if (num_left < 2) - stop_decoding(JPGD_BAD_DHT_MARKER); - - num_left -= 2; - - while (num_left) - { - index = get_bits(8); - - huff_num[0] = 0; - - count = 0; - - for (i = 1; i <= 16; i++) - { - huff_num[i] = static_cast<uint8>(get_bits(8)); - count += huff_num[i]; - } - - if (count > 255) - stop_decoding(JPGD_BAD_DHT_COUNTS); - - for (i = 0; i < count; i++) - huff_val[i] = static_cast<uint8>(get_bits(8)); + // Unconditionally frees all allocated m_blocks. + void jpeg_decoder::free_all_blocks() + { + m_pStream = nullptr; + for (mem_block* b = m_pMem_blocks; b; ) + { + mem_block* n = b->m_pNext; + jpgd_free(b); + b = n; + } + m_pMem_blocks = nullptr; + } + + // This method handles all errors. It will never return. + // It could easily be changed to use C++ exceptions. + JPGD_NORETURN void jpeg_decoder::stop_decoding(jpgd_status status) + { + m_error_code = status; + free_all_blocks(); + longjmp(m_jmp_state, status); + } + + void* jpeg_decoder::alloc(size_t nSize, bool zero) + { + nSize = (JPGD_MAX(nSize, 1) + 3) & ~3; + char* rv = nullptr; + for (mem_block* b = m_pMem_blocks; b; b = b->m_pNext) + { + if ((b->m_used_count + nSize) <= b->m_size) + { + rv = b->m_data + b->m_used_count; + b->m_used_count += nSize; + break; + } + } + if (!rv) + { + int capacity = JPGD_MAX(32768 - 256, (nSize + 2047) & ~2047); + mem_block* b = (mem_block*)jpgd_malloc(sizeof(mem_block) + capacity); + if (!b) + { + stop_decoding(JPGD_NOTENOUGHMEM); + } + + b->m_pNext = m_pMem_blocks; + m_pMem_blocks = b; + b->m_used_count = nSize; + b->m_size = capacity; + rv = b->m_data; + } + if (zero) memset(rv, 0, nSize); + return rv; + } + + void* jpeg_decoder::alloc_aligned(size_t nSize, uint32_t align, bool zero) + { + assert((align >= 1U) && ((align & (align - 1U)) == 0U)); + void *p = alloc(nSize + align - 1U, zero); + p = (void *)( ((uintptr_t)p + (align - 1U)) & ~((uintptr_t)(align - 1U)) ); + return p; + } + + void jpeg_decoder::word_clear(void* p, uint16 c, uint n) + { + uint8* pD = (uint8*)p; + const uint8 l = c & 0xFF, h = (c >> 8) & 0xFF; + while (n) + { + pD[0] = l; + pD[1] = h; + pD += 2; + n--; + } + } + + // Refill the input buffer. + // This method will sit in a loop until (A) the buffer is full or (B) + // the stream's read() method reports and end of file condition. + void jpeg_decoder::prep_in_buffer() + { + m_in_buf_left = 0; + m_pIn_buf_ofs = m_in_buf; + + if (m_eof_flag) + return; + + do + { + int bytes_read = m_pStream->read(m_in_buf + m_in_buf_left, JPGD_IN_BUF_SIZE - m_in_buf_left, &m_eof_flag); + if (bytes_read == -1) + stop_decoding(JPGD_STREAM_READ); + + m_in_buf_left += bytes_read; + } while ((m_in_buf_left < JPGD_IN_BUF_SIZE) && (!m_eof_flag)); + + m_total_bytes_read += m_in_buf_left; + + // Pad the end of the block with M_EOI (prevents the decompressor from going off the rails if the stream is invalid). + // (This dates way back to when this decompressor was written in C/asm, and the all-asm Huffman decoder did some fancy things to increase perf.) + word_clear(m_pIn_buf_ofs + m_in_buf_left, 0xD9FF, 64); + } + + // Read a Huffman code table. + void jpeg_decoder::read_dht_marker() + { + int i, index, count; + uint8 huff_num[17]; + uint8 huff_val[256]; - i = 1 + 16 + count; + uint num_left = get_bits(16); - if (num_left < (uint)i) - stop_decoding(JPGD_BAD_DHT_MARKER); + if (num_left < 2) + stop_decoding(JPGD_BAD_DHT_MARKER); - num_left -= i; + num_left -= 2; - if ((index & 0x10) > 0x10) - stop_decoding(JPGD_BAD_DHT_INDEX); + while (num_left) + { + index = get_bits(8); - index = (index & 0x0F) + ((index & 0x10) >> 4) * (JPGD_MAX_HUFF_TABLES >> 1); + huff_num[0] = 0; - if (index >= JPGD_MAX_HUFF_TABLES) - stop_decoding(JPGD_BAD_DHT_INDEX); + count = 0; - if (!m_huff_num[index]) - m_huff_num[index] = (uint8 *)alloc(17); + for (i = 1; i <= 16; i++) + { + huff_num[i] = static_cast<uint8>(get_bits(8)); + count += huff_num[i]; + } - if (!m_huff_val[index]) - m_huff_val[index] = (uint8 *)alloc(256); + if (count > 255) + stop_decoding(JPGD_BAD_DHT_COUNTS); - m_huff_ac[index] = (index & 0x10) != 0; - memcpy(m_huff_num[index], huff_num, 17); - memcpy(m_huff_val[index], huff_val, 256); - } -} + bool symbol_present[256]; + memset(symbol_present, 0, sizeof(symbol_present)); -// Read a quantization table. -void jpeg_decoder::read_dqt_marker() -{ - int n, i, prec; - uint num_left; - uint temp; + for (i = 0; i < count; i++) + { + const int s = get_bits(8); - num_left = get_bits(16); + // Check for obviously bogus tables. + if (symbol_present[s]) + stop_decoding(JPGD_BAD_DHT_COUNTS); - if (num_left < 2) - stop_decoding(JPGD_BAD_DQT_MARKER); + huff_val[i] = static_cast<uint8_t>(s); + symbol_present[s] = true; + } - num_left -= 2; + i = 1 + 16 + count; - while (num_left) - { - n = get_bits(8); - prec = n >> 4; - n &= 0x0F; + if (num_left < (uint)i) + stop_decoding(JPGD_BAD_DHT_MARKER); - if (n >= JPGD_MAX_QUANT_TABLES) - stop_decoding(JPGD_BAD_DQT_TABLE); + num_left -= i; - if (!m_quant[n]) - m_quant[n] = (jpgd_quant_t *)alloc(64 * sizeof(jpgd_quant_t)); + if ((index & 0x10) > 0x10) + stop_decoding(JPGD_BAD_DHT_INDEX); - // read quantization entries, in zag order - for (i = 0; i < 64; i++) - { - temp = get_bits(8); + index = (index & 0x0F) + ((index & 0x10) >> 4) * (JPGD_MAX_HUFF_TABLES >> 1); - if (prec) - temp = (temp << 8) + get_bits(8); + if (index >= JPGD_MAX_HUFF_TABLES) + stop_decoding(JPGD_BAD_DHT_INDEX); - m_quant[n][i] = static_cast<jpgd_quant_t>(temp); - } + if (!m_huff_num[index]) + m_huff_num[index] = (uint8*)alloc(17); - i = 64 + 1; + if (!m_huff_val[index]) + m_huff_val[index] = (uint8*)alloc(256); - if (prec) - i += 64; + m_huff_ac[index] = (index & 0x10) != 0; + memcpy(m_huff_num[index], huff_num, 17); + memcpy(m_huff_val[index], huff_val, 256); + } + } - if (num_left < (uint)i) - stop_decoding(JPGD_BAD_DQT_LENGTH); + // Read a quantization table. + void jpeg_decoder::read_dqt_marker() + { + int n, i, prec; + uint num_left; + uint temp; - num_left -= i; - } -} + num_left = get_bits(16); -// Read the start of frame (SOF) marker. -void jpeg_decoder::read_sof_marker() -{ - int i; - uint num_left; + if (num_left < 2) + stop_decoding(JPGD_BAD_DQT_MARKER); - num_left = get_bits(16); + num_left -= 2; - if (get_bits(8) != 8) /* precision: sorry, only 8-bit precision is supported right now */ - stop_decoding(JPGD_BAD_PRECISION); + while (num_left) + { + n = get_bits(8); + prec = n >> 4; + n &= 0x0F; - m_image_y_size = get_bits(16); + if (n >= JPGD_MAX_QUANT_TABLES) + stop_decoding(JPGD_BAD_DQT_TABLE); - if ((m_image_y_size < 1) || (m_image_y_size > JPGD_MAX_HEIGHT)) - stop_decoding(JPGD_BAD_HEIGHT); + if (!m_quant[n]) + m_quant[n] = (jpgd_quant_t*)alloc(64 * sizeof(jpgd_quant_t)); - m_image_x_size = get_bits(16); + // read quantization entries, in zag order + for (i = 0; i < 64; i++) + { + temp = get_bits(8); - if ((m_image_x_size < 1) || (m_image_x_size > JPGD_MAX_WIDTH)) - stop_decoding(JPGD_BAD_WIDTH); + if (prec) + temp = (temp << 8) + get_bits(8); - m_comps_in_frame = get_bits(8); + m_quant[n][i] = static_cast<jpgd_quant_t>(temp); + } - if (m_comps_in_frame > JPGD_MAX_COMPONENTS) - stop_decoding(JPGD_TOO_MANY_COMPONENTS); + i = 64 + 1; - if (num_left != (uint)(m_comps_in_frame * 3 + 8)) - stop_decoding(JPGD_BAD_SOF_LENGTH); + if (prec) + i += 64; - for (i = 0; i < m_comps_in_frame; i++) - { - m_comp_ident[i] = get_bits(8); - m_comp_h_samp[i] = get_bits(4); - m_comp_v_samp[i] = get_bits(4); - m_comp_quant[i] = get_bits(8); - } -} + if (num_left < (uint)i) + stop_decoding(JPGD_BAD_DQT_LENGTH); -// Used to skip unrecognized markers. -void jpeg_decoder::skip_variable_marker() -{ - uint num_left; + num_left -= i; + } + } - num_left = get_bits(16); + // Read the start of frame (SOF) marker. + void jpeg_decoder::read_sof_marker() + { + int i; + uint num_left; - if (num_left < 2) - stop_decoding(JPGD_BAD_VARIABLE_MARKER); + num_left = get_bits(16); - num_left -= 2; + /* precision: sorry, only 8-bit precision is supported */ + if (get_bits(8) != 8) + stop_decoding(JPGD_BAD_PRECISION); - while (num_left) - { - get_bits(8); - num_left--; - } -} + m_image_y_size = get_bits(16); -// Read a define restart interval (DRI) marker. -void jpeg_decoder::read_dri_marker() -{ - if (get_bits(16) != 4) - stop_decoding(JPGD_BAD_DRI_LENGTH); + if ((m_image_y_size < 1) || (m_image_y_size > JPGD_MAX_HEIGHT)) + stop_decoding(JPGD_BAD_HEIGHT); - m_restart_interval = get_bits(16); -} + m_image_x_size = get_bits(16); -// Read a start of scan (SOS) marker. -void jpeg_decoder::read_sos_marker() -{ - uint num_left; - int i, ci, n, c, cc; + if ((m_image_x_size < 1) || (m_image_x_size > JPGD_MAX_WIDTH)) + stop_decoding(JPGD_BAD_WIDTH); - num_left = get_bits(16); + m_comps_in_frame = get_bits(8); - n = get_bits(8); - - m_comps_in_scan = n; - - num_left -= 3; - - if ( (num_left != (uint)(n * 2 + 3)) || (n < 1) || (n > JPGD_MAX_COMPS_IN_SCAN) ) - stop_decoding(JPGD_BAD_SOS_LENGTH); - - for (i = 0; i < n; i++) - { - cc = get_bits(8); - c = get_bits(8); - num_left -= 2; - - for (ci = 0; ci < m_comps_in_frame; ci++) - if (cc == m_comp_ident[ci]) - break; - - if (ci >= m_comps_in_frame) - stop_decoding(JPGD_BAD_SOS_COMP_ID); - - m_comp_list[i] = ci; - m_comp_dc_tab[ci] = (c >> 4) & 15; - m_comp_ac_tab[ci] = (c & 15) + (JPGD_MAX_HUFF_TABLES >> 1); - } - - m_spectral_start = get_bits(8); - m_spectral_end = get_bits(8); - m_successive_high = get_bits(4); - m_successive_low = get_bits(4); - - if (!m_progressive_flag) - { - m_spectral_start = 0; - m_spectral_end = 63; - } - - num_left -= 3; - - while (num_left) /* read past whatever is num_left */ - { - get_bits(8); - num_left--; - } -} - -// Finds the next marker. -int jpeg_decoder::next_marker() -{ - uint c, bytes; - - bytes = 0; - - do - { - do - { - bytes++; - c = get_bits(8); - } while (c != 0xFF); - - do - { - c = get_bits(8); - } while (c == 0xFF); - - } while (c == 0); - - // If bytes > 0 here, there where extra bytes before the marker (not good). - - return c; -} - -// Process markers. Returns when an SOFx, SOI, EOI, or SOS marker is -// encountered. -int jpeg_decoder::process_markers() -{ - int c; - - for ( ; ; ) - { - c = next_marker(); - - switch (c) - { - case M_SOF0: - case M_SOF1: - case M_SOF2: - case M_SOF3: - case M_SOF5: - case M_SOF6: - case M_SOF7: -// case M_JPG: - case M_SOF9: - case M_SOF10: - case M_SOF11: - case M_SOF13: - case M_SOF14: - case M_SOF15: - case M_SOI: - case M_EOI: - case M_SOS: - { - return c; - } - case M_DHT: - { - read_dht_marker(); - break; - } - // No arithmitic support - dumb patents! - case M_DAC: - { - stop_decoding(JPGD_NO_ARITHMITIC_SUPPORT); - break; - } - case M_DQT: - { - read_dqt_marker(); - break; - } - case M_DRI: - { - read_dri_marker(); - break; - } - //case M_APP0: /* no need to read the JFIF marker */ - - case M_JPG: - case M_RST0: /* no parameters */ - case M_RST1: - case M_RST2: - case M_RST3: - case M_RST4: - case M_RST5: - case M_RST6: - case M_RST7: - case M_TEM: - { - stop_decoding(JPGD_UNEXPECTED_MARKER); - break; - } - default: /* must be DNL, DHP, EXP, APPn, JPGn, COM, or RESn or APP0 */ - { - skip_variable_marker(); - break; - } - } - } -} - -// Finds the start of image (SOI) marker. -// This code is rather defensive: it only checks the first 512 bytes to avoid -// false positives. -void jpeg_decoder::locate_soi_marker() -{ - uint lastchar, thischar; - uint bytesleft; - - lastchar = get_bits(8); - - thischar = get_bits(8); - - /* ok if it's a normal JPEG file without a special header */ - - if ((lastchar == 0xFF) && (thischar == M_SOI)) - return; - - bytesleft = 4096; //512; - - for ( ; ; ) - { - if (--bytesleft == 0) - stop_decoding(JPGD_NOT_JPEG); - - lastchar = thischar; - - thischar = get_bits(8); - - if (lastchar == 0xFF) - { - if (thischar == M_SOI) - break; - else if (thischar == M_EOI) // get_bits will keep returning M_EOI if we read past the end - stop_decoding(JPGD_NOT_JPEG); - } - } - - // Check the next character after marker: if it's not 0xFF, it can't be the start of the next marker, so the file is bad. - thischar = (m_bit_buf >> 24) & 0xFF; - - if (thischar != 0xFF) - stop_decoding(JPGD_NOT_JPEG); -} - -// Find a start of frame (SOF) marker. -void jpeg_decoder::locate_sof_marker() -{ - locate_soi_marker(); - - int c = process_markers(); - - switch (c) - { - case M_SOF2: - m_progressive_flag = JPGD_TRUE; - case M_SOF0: /* baseline DCT */ - case M_SOF1: /* extended sequential DCT */ - { - read_sof_marker(); - break; - } - case M_SOF9: /* Arithmitic coding */ - { - stop_decoding(JPGD_NO_ARITHMITIC_SUPPORT); - break; - } - default: - { - stop_decoding(JPGD_UNSUPPORTED_MARKER); - break; - } - } -} - -// Find a start of scan (SOS) marker. -int jpeg_decoder::locate_sos_marker() -{ - int c; - - c = process_markers(); - - if (c == M_EOI) - return JPGD_FALSE; - else if (c != M_SOS) - stop_decoding(JPGD_UNEXPECTED_MARKER); - - read_sos_marker(); - - return JPGD_TRUE; -} - -// Reset everything to default/uninitialized state. -void jpeg_decoder::init(jpeg_decoder_stream *pStream) -{ - m_pMem_blocks = NULL; - m_error_code = JPGD_SUCCESS; - m_ready_flag = false; - m_image_x_size = m_image_y_size = 0; - m_pStream = pStream; - m_progressive_flag = JPGD_FALSE; - - memset(m_huff_ac, 0, sizeof(m_huff_ac)); - memset(m_huff_num, 0, sizeof(m_huff_num)); - memset(m_huff_val, 0, sizeof(m_huff_val)); - memset(m_quant, 0, sizeof(m_quant)); - - m_scan_type = 0; - m_comps_in_frame = 0; - - memset(m_comp_h_samp, 0, sizeof(m_comp_h_samp)); - memset(m_comp_v_samp, 0, sizeof(m_comp_v_samp)); - memset(m_comp_quant, 0, sizeof(m_comp_quant)); - memset(m_comp_ident, 0, sizeof(m_comp_ident)); - memset(m_comp_h_blocks, 0, sizeof(m_comp_h_blocks)); - memset(m_comp_v_blocks, 0, sizeof(m_comp_v_blocks)); - - m_comps_in_scan = 0; - memset(m_comp_list, 0, sizeof(m_comp_list)); - memset(m_comp_dc_tab, 0, sizeof(m_comp_dc_tab)); - memset(m_comp_ac_tab, 0, sizeof(m_comp_ac_tab)); - - m_spectral_start = 0; - m_spectral_end = 0; - m_successive_low = 0; - m_successive_high = 0; - m_max_mcu_x_size = 0; - m_max_mcu_y_size = 0; - m_blocks_per_mcu = 0; - m_max_blocks_per_row = 0; - m_mcus_per_row = 0; - m_mcus_per_col = 0; - m_expanded_blocks_per_component = 0; - m_expanded_blocks_per_mcu = 0; - m_expanded_blocks_per_row = 0; - m_freq_domain_chroma_upsample = false; - - memset(m_mcu_org, 0, sizeof(m_mcu_org)); - - m_total_lines_left = 0; - m_mcu_lines_left = 0; - m_real_dest_bytes_per_scan_line = 0; - m_dest_bytes_per_scan_line = 0; - m_dest_bytes_per_pixel = 0; - - memset(m_pHuff_tabs, 0, sizeof(m_pHuff_tabs)); - - memset(m_dc_coeffs, 0, sizeof(m_dc_coeffs)); - memset(m_ac_coeffs, 0, sizeof(m_ac_coeffs)); - memset(m_block_y_mcu, 0, sizeof(m_block_y_mcu)); - - m_eob_run = 0; - - memset(m_block_y_mcu, 0, sizeof(m_block_y_mcu)); - - m_pIn_buf_ofs = m_in_buf; - m_in_buf_left = 0; - m_eof_flag = false; - m_tem_flag = 0; - - memset(m_in_buf_pad_start, 0, sizeof(m_in_buf_pad_start)); - memset(m_in_buf, 0, sizeof(m_in_buf)); - memset(m_in_buf_pad_end, 0, sizeof(m_in_buf_pad_end)); - - m_restart_interval = 0; - m_restarts_left = 0; - m_next_restart_num = 0; - - m_max_mcus_per_row = 0; - m_max_blocks_per_mcu = 0; - m_max_mcus_per_col = 0; - - memset(m_last_dc_val, 0, sizeof(m_last_dc_val)); - m_pMCU_coefficients = NULL; - m_pSample_buf = NULL; - - m_total_bytes_read = 0; - - m_pScan_line_0 = NULL; - m_pScan_line_1 = NULL; - - // Ready the input buffer. - prep_in_buffer(); - - // Prime the bit buffer. - m_bits_left = 16; - m_bit_buf = 0; - - get_bits(16); - get_bits(16); - - for (int i = 0; i < JPGD_MAX_BLOCKS_PER_MCU; i++) - m_mcu_block_max_zag[i] = 64; -} + if (m_comps_in_frame > JPGD_MAX_COMPONENTS) + stop_decoding(JPGD_TOO_MANY_COMPONENTS); + + if (num_left != (uint)(m_comps_in_frame * 3 + 8)) + stop_decoding(JPGD_BAD_SOF_LENGTH); + + for (i = 0; i < m_comps_in_frame; i++) + { + m_comp_ident[i] = get_bits(8); + m_comp_h_samp[i] = get_bits(4); + m_comp_v_samp[i] = get_bits(4); + + if (!m_comp_h_samp[i] || !m_comp_v_samp[i] || (m_comp_h_samp[i] > 2) || (m_comp_v_samp[i] > 2)) + stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); + + m_comp_quant[i] = get_bits(8); + if (m_comp_quant[i] >= JPGD_MAX_QUANT_TABLES) + stop_decoding(JPGD_DECODE_ERROR); + } + } + + // Used to skip unrecognized markers. + void jpeg_decoder::skip_variable_marker() + { + uint num_left; + + num_left = get_bits(16); + + if (num_left < 2) + stop_decoding(JPGD_BAD_VARIABLE_MARKER); + + num_left -= 2; + + while (num_left) + { + get_bits(8); + num_left--; + } + } + + // Read a define restart interval (DRI) marker. + void jpeg_decoder::read_dri_marker() + { + if (get_bits(16) != 4) + stop_decoding(JPGD_BAD_DRI_LENGTH); + + m_restart_interval = get_bits(16); + } + + // Read a start of scan (SOS) marker. + void jpeg_decoder::read_sos_marker() + { + uint num_left; + int i, ci, n, c, cc; + + num_left = get_bits(16); + + n = get_bits(8); + + m_comps_in_scan = n; + + num_left -= 3; + + if ((num_left != (uint)(n * 2 + 3)) || (n < 1) || (n > JPGD_MAX_COMPS_IN_SCAN)) + stop_decoding(JPGD_BAD_SOS_LENGTH); + + for (i = 0; i < n; i++) + { + cc = get_bits(8); + c = get_bits(8); + num_left -= 2; + + for (ci = 0; ci < m_comps_in_frame; ci++) + if (cc == m_comp_ident[ci]) + break; + + if (ci >= m_comps_in_frame) + stop_decoding(JPGD_BAD_SOS_COMP_ID); + + if (ci >= JPGD_MAX_COMPONENTS) + stop_decoding(JPGD_DECODE_ERROR); + + m_comp_list[i] = ci; + + m_comp_dc_tab[ci] = (c >> 4) & 15; + m_comp_ac_tab[ci] = (c & 15) + (JPGD_MAX_HUFF_TABLES >> 1); + + if (m_comp_dc_tab[ci] >= JPGD_MAX_HUFF_TABLES) + stop_decoding(JPGD_DECODE_ERROR); + + if (m_comp_ac_tab[ci] >= JPGD_MAX_HUFF_TABLES) + stop_decoding(JPGD_DECODE_ERROR); + } + + m_spectral_start = get_bits(8); + m_spectral_end = get_bits(8); + m_successive_high = get_bits(4); + m_successive_low = get_bits(4); + + if (!m_progressive_flag) + { + m_spectral_start = 0; + m_spectral_end = 63; + } + + num_left -= 3; + + /* read past whatever is num_left */ + while (num_left) + { + get_bits(8); + num_left--; + } + } + + // Finds the next marker. + int jpeg_decoder::next_marker() + { + uint c, bytes; + + bytes = 0; + + do + { + do + { + bytes++; + c = get_bits(8); + } while (c != 0xFF); + + do + { + c = get_bits(8); + } while (c == 0xFF); + + } while (c == 0); + + // If bytes > 0 here, there where extra bytes before the marker (not good). + + return c; + } + + // Process markers. Returns when an SOFx, SOI, EOI, or SOS marker is + // encountered. + int jpeg_decoder::process_markers() + { + int c; + + for (; ; ) + { + c = next_marker(); + + switch (c) + { + case M_SOF0: + case M_SOF1: + case M_SOF2: + case M_SOF3: + case M_SOF5: + case M_SOF6: + case M_SOF7: + // case M_JPG: + case M_SOF9: + case M_SOF10: + case M_SOF11: + case M_SOF13: + case M_SOF14: + case M_SOF15: + case M_SOI: + case M_EOI: + case M_SOS: + { + return c; + } + case M_DHT: + { + read_dht_marker(); + break; + } + // No arithmitic support - dumb patents! + case M_DAC: + { + stop_decoding(JPGD_NO_ARITHMITIC_SUPPORT); + break; + } + case M_DQT: + { + read_dqt_marker(); + break; + } + case M_DRI: + { + read_dri_marker(); + break; + } + //case M_APP0: /* no need to read the JFIF marker */ + case M_JPG: + case M_RST0: /* no parameters */ + case M_RST1: + case M_RST2: + case M_RST3: + case M_RST4: + case M_RST5: + case M_RST6: + case M_RST7: + case M_TEM: + { + stop_decoding(JPGD_UNEXPECTED_MARKER); + break; + } + default: /* must be DNL, DHP, EXP, APPn, JPGn, COM, or RESn or APP0 */ + { + skip_variable_marker(); + break; + } + } + } + } + + // Finds the start of image (SOI) marker. + void jpeg_decoder::locate_soi_marker() + { + uint lastchar, thischar; + uint bytesleft; + + lastchar = get_bits(8); + + thischar = get_bits(8); + + /* ok if it's a normal JPEG file without a special header */ + + if ((lastchar == 0xFF) && (thischar == M_SOI)) + return; + + bytesleft = 4096; + + for (; ; ) + { + if (--bytesleft == 0) + stop_decoding(JPGD_NOT_JPEG); + + lastchar = thischar; + + thischar = get_bits(8); + + if (lastchar == 0xFF) + { + if (thischar == M_SOI) + break; + else if (thischar == M_EOI) // get_bits will keep returning M_EOI if we read past the end + stop_decoding(JPGD_NOT_JPEG); + } + } + + // Check the next character after marker: if it's not 0xFF, it can't be the start of the next marker, so the file is bad. + thischar = (m_bit_buf >> 24) & 0xFF; + + if (thischar != 0xFF) + stop_decoding(JPGD_NOT_JPEG); + } + + // Find a start of frame (SOF) marker. + void jpeg_decoder::locate_sof_marker() + { + locate_soi_marker(); + + int c = process_markers(); + + switch (c) + { + case M_SOF2: + { + m_progressive_flag = JPGD_TRUE; + read_sof_marker(); + break; + } + case M_SOF0: /* baseline DCT */ + case M_SOF1: /* extended sequential DCT */ + { + read_sof_marker(); + break; + } + case M_SOF9: /* Arithmitic coding */ + { + stop_decoding(JPGD_NO_ARITHMITIC_SUPPORT); + break; + } + default: + { + stop_decoding(JPGD_UNSUPPORTED_MARKER); + break; + } + } + } + + // Find a start of scan (SOS) marker. + int jpeg_decoder::locate_sos_marker() + { + int c; + + c = process_markers(); + + if (c == M_EOI) + return JPGD_FALSE; + else if (c != M_SOS) + stop_decoding(JPGD_UNEXPECTED_MARKER); + + read_sos_marker(); + + return JPGD_TRUE; + } + + // Reset everything to default/uninitialized state. + void jpeg_decoder::init(jpeg_decoder_stream* pStream, uint32_t flags) + { + m_flags = flags; + m_pMem_blocks = nullptr; + m_error_code = JPGD_SUCCESS; + m_ready_flag = false; + m_image_x_size = m_image_y_size = 0; + m_pStream = pStream; + m_progressive_flag = JPGD_FALSE; + + memset(m_huff_ac, 0, sizeof(m_huff_ac)); + memset(m_huff_num, 0, sizeof(m_huff_num)); + memset(m_huff_val, 0, sizeof(m_huff_val)); + memset(m_quant, 0, sizeof(m_quant)); + + m_scan_type = 0; + m_comps_in_frame = 0; + + memset(m_comp_h_samp, 0, sizeof(m_comp_h_samp)); + memset(m_comp_v_samp, 0, sizeof(m_comp_v_samp)); + memset(m_comp_quant, 0, sizeof(m_comp_quant)); + memset(m_comp_ident, 0, sizeof(m_comp_ident)); + memset(m_comp_h_blocks, 0, sizeof(m_comp_h_blocks)); + memset(m_comp_v_blocks, 0, sizeof(m_comp_v_blocks)); + + m_comps_in_scan = 0; + memset(m_comp_list, 0, sizeof(m_comp_list)); + memset(m_comp_dc_tab, 0, sizeof(m_comp_dc_tab)); + memset(m_comp_ac_tab, 0, sizeof(m_comp_ac_tab)); + + m_spectral_start = 0; + m_spectral_end = 0; + m_successive_low = 0; + m_successive_high = 0; + m_max_mcu_x_size = 0; + m_max_mcu_y_size = 0; + m_blocks_per_mcu = 0; + m_max_blocks_per_row = 0; + m_mcus_per_row = 0; + m_mcus_per_col = 0; + + memset(m_mcu_org, 0, sizeof(m_mcu_org)); + + m_total_lines_left = 0; + m_mcu_lines_left = 0; + m_num_buffered_scanlines = 0; + m_real_dest_bytes_per_scan_line = 0; + m_dest_bytes_per_scan_line = 0; + m_dest_bytes_per_pixel = 0; + + memset(m_pHuff_tabs, 0, sizeof(m_pHuff_tabs)); + + memset(m_dc_coeffs, 0, sizeof(m_dc_coeffs)); + memset(m_ac_coeffs, 0, sizeof(m_ac_coeffs)); + memset(m_block_y_mcu, 0, sizeof(m_block_y_mcu)); + + m_eob_run = 0; + + m_pIn_buf_ofs = m_in_buf; + m_in_buf_left = 0; + m_eof_flag = false; + m_tem_flag = 0; + + memset(m_in_buf_pad_start, 0, sizeof(m_in_buf_pad_start)); + memset(m_in_buf, 0, sizeof(m_in_buf)); + memset(m_in_buf_pad_end, 0, sizeof(m_in_buf_pad_end)); + + m_restart_interval = 0; + m_restarts_left = 0; + m_next_restart_num = 0; + + m_max_mcus_per_row = 0; + m_max_blocks_per_mcu = 0; + m_max_mcus_per_col = 0; + + memset(m_last_dc_val, 0, sizeof(m_last_dc_val)); + m_pMCU_coefficients = nullptr; + m_pSample_buf = nullptr; + m_pSample_buf_prev = nullptr; + m_sample_buf_prev_valid = false; + + m_total_bytes_read = 0; + + m_pScan_line_0 = nullptr; + m_pScan_line_1 = nullptr; + + // Ready the input buffer. + prep_in_buffer(); + + // Prime the bit buffer. + m_bits_left = 16; + m_bit_buf = 0; + + get_bits(16); + get_bits(16); + + for (int i = 0; i < JPGD_MAX_BLOCKS_PER_MCU; i++) + m_mcu_block_max_zag[i] = 64; + + m_has_sse2 = false; + +#if JPGD_USE_SSE2 +#ifdef _MSC_VER + int cpu_info[4]; + __cpuid(cpu_info, 1); + const int cpu_info3 = cpu_info[3]; + m_has_sse2 = ((cpu_info3 >> 26U) & 1U) != 0U; +#else + m_has_sse2 = true; +#endif +#endif + } #define SCALEBITS 16 #define ONE_HALF ((int) 1 << (SCALEBITS-1)) #define FIX(x) ((int) ((x) * (1L<<SCALEBITS) + 0.5f)) -// Create a few tables that allow us to quickly convert YCbCr to RGB. -void jpeg_decoder::create_look_ups() -{ - for (int i = 0; i <= 255; i++) - { - int k = i - 128; - m_crr[i] = ( FIX(1.40200f) * k + ONE_HALF) >> SCALEBITS; - m_cbb[i] = ( FIX(1.77200f) * k + ONE_HALF) >> SCALEBITS; - m_crg[i] = (-FIX(0.71414f)) * k; - m_cbg[i] = (-FIX(0.34414f)) * k + ONE_HALF; - } -} - -// This method throws back into the stream any bytes that where read -// into the bit buffer during initial marker scanning. -void jpeg_decoder::fix_in_buffer() -{ - // In case any 0xFF's where pulled into the buffer during marker scanning. - JPGD_ASSERT((m_bits_left & 7) == 0); - - if (m_bits_left == 16) - stuff_char( (uint8)(m_bit_buf & 0xFF)); - - if (m_bits_left >= 8) - stuff_char( (uint8)((m_bit_buf >> 8) & 0xFF)); - - stuff_char((uint8)((m_bit_buf >> 16) & 0xFF)); - stuff_char((uint8)((m_bit_buf >> 24) & 0xFF)); - - m_bits_left = 16; - get_bits_no_markers(16); - get_bits_no_markers(16); -} - -void jpeg_decoder::transform_mcu(int mcu_row) -{ - jpgd_block_t* pSrc_ptr = m_pMCU_coefficients; - if (m_freq_domain_chroma_upsample) { - JPGD_ASSERT(mcu_row * m_blocks_per_mcu < m_expanded_blocks_per_row); - } - else { - JPGD_ASSERT(mcu_row * m_blocks_per_mcu < m_max_blocks_per_row); - } - uint8* pDst_ptr = m_pSample_buf + mcu_row * m_blocks_per_mcu * 64; - - for (int mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) - { - idct(pSrc_ptr, pDst_ptr, m_mcu_block_max_zag[mcu_block]); - pSrc_ptr += 64; - pDst_ptr += 64; - } -} - -static const uint8 s_max_rc[64] = -{ - 17, 18, 34, 50, 50, 51, 52, 52, 52, 68, 84, 84, 84, 84, 85, 86, 86, 86, 86, 86, - 102, 118, 118, 118, 118, 118, 118, 119, 120, 120, 120, 120, 120, 120, 120, 136, - 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, - 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136, 136 -}; - -void jpeg_decoder::transform_mcu_expand(int mcu_row) -{ - jpgd_block_t* pSrc_ptr = m_pMCU_coefficients; - uint8* pDst_ptr = m_pSample_buf + mcu_row * m_expanded_blocks_per_mcu * 64; - - // Y IDCT - int mcu_block; - for (mcu_block = 0; mcu_block < m_expanded_blocks_per_component; mcu_block++) - { - idct(pSrc_ptr, pDst_ptr, m_mcu_block_max_zag[mcu_block]); - pSrc_ptr += 64; - pDst_ptr += 64; - } - - // Chroma IDCT, with upsampling - jpgd_block_t temp_block[64]; - - for (int i = 0; i < 2; i++) - { - DCT_Upsample::Matrix44 P, Q, R, S; - - JPGD_ASSERT(m_mcu_block_max_zag[mcu_block] >= 1); - JPGD_ASSERT(m_mcu_block_max_zag[mcu_block] <= 64); - - int max_zag = m_mcu_block_max_zag[mcu_block++] - 1; - if (max_zag <= 0) max_zag = 0; // should never happen, only here to shut up static analysis - switch (s_max_rc[max_zag]) - { - case 1*16+1: - DCT_Upsample::P_Q<1, 1>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<1, 1>::calc(R, S, pSrc_ptr); - break; - case 1*16+2: - DCT_Upsample::P_Q<1, 2>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<1, 2>::calc(R, S, pSrc_ptr); - break; - case 2*16+2: - DCT_Upsample::P_Q<2, 2>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<2, 2>::calc(R, S, pSrc_ptr); - break; - case 3*16+2: - DCT_Upsample::P_Q<3, 2>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<3, 2>::calc(R, S, pSrc_ptr); - break; - case 3*16+3: - DCT_Upsample::P_Q<3, 3>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<3, 3>::calc(R, S, pSrc_ptr); - break; - case 3*16+4: - DCT_Upsample::P_Q<3, 4>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<3, 4>::calc(R, S, pSrc_ptr); - break; - case 4*16+4: - DCT_Upsample::P_Q<4, 4>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<4, 4>::calc(R, S, pSrc_ptr); - break; - case 5*16+4: - DCT_Upsample::P_Q<5, 4>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<5, 4>::calc(R, S, pSrc_ptr); - break; - case 5*16+5: - DCT_Upsample::P_Q<5, 5>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<5, 5>::calc(R, S, pSrc_ptr); - break; - case 5*16+6: - DCT_Upsample::P_Q<5, 6>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<5, 6>::calc(R, S, pSrc_ptr); - break; - case 6*16+6: - DCT_Upsample::P_Q<6, 6>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<6, 6>::calc(R, S, pSrc_ptr); - break; - case 7*16+6: - DCT_Upsample::P_Q<7, 6>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<7, 6>::calc(R, S, pSrc_ptr); - break; - case 7*16+7: - DCT_Upsample::P_Q<7, 7>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<7, 7>::calc(R, S, pSrc_ptr); - break; - case 7*16+8: - DCT_Upsample::P_Q<7, 8>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<7, 8>::calc(R, S, pSrc_ptr); - break; - case 8*16+8: - DCT_Upsample::P_Q<8, 8>::calc(P, Q, pSrc_ptr); - DCT_Upsample::R_S<8, 8>::calc(R, S, pSrc_ptr); - break; - default: - JPGD_ASSERT(false); - } - - DCT_Upsample::Matrix44 a(P + Q); P -= Q; - DCT_Upsample::Matrix44& b = P; - DCT_Upsample::Matrix44 c(R + S); R -= S; - DCT_Upsample::Matrix44& d = R; - - DCT_Upsample::Matrix44::add_and_store(temp_block, a, c); - idct_4x4(temp_block, pDst_ptr); - pDst_ptr += 64; - - DCT_Upsample::Matrix44::sub_and_store(temp_block, a, c); - idct_4x4(temp_block, pDst_ptr); - pDst_ptr += 64; - - DCT_Upsample::Matrix44::add_and_store(temp_block, b, d); - idct_4x4(temp_block, pDst_ptr); - pDst_ptr += 64; - - DCT_Upsample::Matrix44::sub_and_store(temp_block, b, d); - idct_4x4(temp_block, pDst_ptr); - pDst_ptr += 64; - - pSrc_ptr += 64; - } -} - -// Loads and dequantizes the next row of (already decoded) coefficients. -// Progressive images only. -void jpeg_decoder::load_next_row() -{ - int i; - jpgd_block_t *p; - jpgd_quant_t *q; - int mcu_row, mcu_block, row_block = 0; - int component_num, component_id; - int block_x_mcu[JPGD_MAX_COMPONENTS]; - - memset(block_x_mcu, 0, JPGD_MAX_COMPONENTS * sizeof(int)); - - for (mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) - { - int block_x_mcu_ofs = 0, block_y_mcu_ofs = 0; - - for (mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) - { - component_id = m_mcu_org[mcu_block]; - JPGD_ASSERT(m_comp_quant[component_id] < JPGD_MAX_QUANT_TABLES); - q = m_quant[m_comp_quant[component_id]]; - - p = m_pMCU_coefficients + 64 * mcu_block; - - jpgd_block_t* pAC = coeff_buf_getp(m_ac_coeffs[component_id], block_x_mcu[component_id] + block_x_mcu_ofs, m_block_y_mcu[component_id] + block_y_mcu_ofs); - jpgd_block_t* pDC = coeff_buf_getp(m_dc_coeffs[component_id], block_x_mcu[component_id] + block_x_mcu_ofs, m_block_y_mcu[component_id] + block_y_mcu_ofs); - p[0] = pDC[0]; - memcpy(&p[1], &pAC[1], 63 * sizeof(jpgd_block_t)); - - for (i = 63; i > 0; i--) - if (p[g_ZAG[i]]) - break; - - m_mcu_block_max_zag[mcu_block] = i + 1; - - for ( ; i >= 0; i--) - if (p[g_ZAG[i]]) - p[g_ZAG[i]] = static_cast<jpgd_block_t>(p[g_ZAG[i]] * q[i]); - - row_block++; - - if (m_comps_in_scan == 1) - block_x_mcu[component_id]++; - else - { - if (++block_x_mcu_ofs == m_comp_h_samp[component_id]) - { - block_x_mcu_ofs = 0; - - if (++block_y_mcu_ofs == m_comp_v_samp[component_id]) - { - block_y_mcu_ofs = 0; - - block_x_mcu[component_id] += m_comp_h_samp[component_id]; - } - } - } - } - - if (m_freq_domain_chroma_upsample) - transform_mcu_expand(mcu_row); - else - transform_mcu(mcu_row); - } - - if (m_comps_in_scan == 1) - m_block_y_mcu[m_comp_list[0]]++; - else - { - for (component_num = 0; component_num < m_comps_in_scan; component_num++) - { - component_id = m_comp_list[component_num]; - - m_block_y_mcu[component_id] += m_comp_v_samp[component_id]; - } - } -} - -// Restart interval processing. -void jpeg_decoder::process_restart() -{ - int i; - int c = 0; - - // Align to a byte boundry - // FIXME: Is this really necessary? get_bits_no_markers() never reads in markers! - //get_bits_no_markers(m_bits_left & 7); - - // Let's scan a little bit to find the marker, but not _too_ far. - // 1536 is a "fudge factor" that determines how much to scan. - for (i = 1536; i > 0; i--) - if (get_char() == 0xFF) - break; - - if (i == 0) - stop_decoding(JPGD_BAD_RESTART_MARKER); - - for ( ; i > 0; i--) - if ((c = get_char()) != 0xFF) - break; - - if (i == 0) - stop_decoding(JPGD_BAD_RESTART_MARKER); - - // Is it the expected marker? If not, something bad happened. - if (c != (m_next_restart_num + M_RST0)) - stop_decoding(JPGD_BAD_RESTART_MARKER); - - // Reset each component's DC prediction values. - memset(&m_last_dc_val, 0, m_comps_in_frame * sizeof(uint)); - - m_eob_run = 0; - - m_restarts_left = m_restart_interval; - - m_next_restart_num = (m_next_restart_num + 1) & 7; - - // Get the bit buffer going again... - - m_bits_left = 16; - get_bits_no_markers(16); - get_bits_no_markers(16); -} - -static inline int dequantize_ac(int c, int q) { c *= q; return c; } - -// Decodes and dequantizes the next row of coefficients. -void jpeg_decoder::decode_next_row() -{ - int row_block = 0; - - for (int mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) - { - if ((m_restart_interval) && (m_restarts_left == 0)) - process_restart(); - - jpgd_block_t* p = m_pMCU_coefficients; - for (int mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++, p += 64) - { - int component_id = m_mcu_org[mcu_block]; - JPGD_ASSERT(m_comp_quant[component_id] < JPGD_MAX_QUANT_TABLES); - jpgd_quant_t* q = m_quant[m_comp_quant[component_id]]; - - int r, s; - s = huff_decode(m_pHuff_tabs[m_comp_dc_tab[component_id]], r); - s = JPGD_HUFF_EXTEND(r, s); - - m_last_dc_val[component_id] = (s += m_last_dc_val[component_id]); - - p[0] = static_cast<jpgd_block_t>(s * q[0]); - - int prev_num_set = m_mcu_block_max_zag[mcu_block]; - - huff_tables *pH = m_pHuff_tabs[m_comp_ac_tab[component_id]]; - - int k; - for (k = 1; k < 64; k++) - { - int extra_bits; - s = huff_decode(pH, extra_bits); - - r = s >> 4; - s &= 15; - - if (s) - { - if (r) - { - if ((k + r) > 63) - stop_decoding(JPGD_DECODE_ERROR); - - if (k < prev_num_set) - { - int n = JPGD_MIN(r, prev_num_set - k); - int kt = k; - while (n--) - p[g_ZAG[kt++]] = 0; - } - - k += r; - } - - s = JPGD_HUFF_EXTEND(extra_bits, s); - - JPGD_ASSERT(k < 64); - - p[g_ZAG[k]] = static_cast<jpgd_block_t>(dequantize_ac(s, q[k])); //s * q[k]; - } - else - { - if (r == 15) - { - if ((k + 16) > 64) - stop_decoding(JPGD_DECODE_ERROR); - - if (k < prev_num_set) - { - int n = JPGD_MIN(16, prev_num_set - k); - int kt = k; - while (n--) - { - JPGD_ASSERT(kt <= 63); - p[g_ZAG[kt++]] = 0; - } - } - - k += 16 - 1; // - 1 because the loop counter is k - JPGD_ASSERT(p[g_ZAG[k]] == 0); - } - else - break; - } - } - - if (k < prev_num_set) - { - int kt = k; - while (kt < prev_num_set) - p[g_ZAG[kt++]] = 0; - } - - m_mcu_block_max_zag[mcu_block] = k; - - row_block++; - } - - if (m_freq_domain_chroma_upsample) - transform_mcu_expand(mcu_row); - else - transform_mcu(mcu_row); - - m_restarts_left--; - } -} - -// YCbCr H1V1 (1x1:1:1, 3 m_blocks per MCU) to RGB -void jpeg_decoder::H1V1Convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - uint8 *d = m_pScan_line_0; - uint8 *s = m_pSample_buf + row * 8; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - for (int j = 0; j < 8; j++) - { - int y = s[j]; - int cb = s[64+j]; - int cr = s[128+j]; - - d[0] = clamp(y + m_crr[cr]); - d[1] = clamp(y + ((m_crg[cr] + m_cbg[cb]) >> 16)); - d[2] = clamp(y + m_cbb[cb]); - d[3] = 255; - - d += 4; - } - - s += 64*3; - } -} - -// YCbCr H2V1 (2x1:1:1, 4 m_blocks per MCU) to RGB -void jpeg_decoder::H2V1Convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - uint8 *d0 = m_pScan_line_0; - uint8 *y = m_pSample_buf + row * 8; - uint8 *c = m_pSample_buf + 2*64 + row * 8; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - for (int l = 0; l < 2; l++) - { - for (int j = 0; j < 4; j++) - { - int cb = c[0]; - int cr = c[64]; - - int rc = m_crr[cr]; - int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); - int bc = m_cbb[cb]; - - int yy = y[j<<1]; - d0[0] = clamp(yy+rc); - d0[1] = clamp(yy+gc); - d0[2] = clamp(yy+bc); - d0[3] = 255; - - yy = y[(j<<1)+1]; - d0[4] = clamp(yy+rc); - d0[5] = clamp(yy+gc); - d0[6] = clamp(yy+bc); - d0[7] = 255; - - d0 += 8; - - c++; - } - y += 64; - } - - y += 64*4 - 64*2; - c += 64*4 - 8; - } -} - -// YCbCr H2V1 (1x2:1:1, 4 m_blocks per MCU) to RGB -void jpeg_decoder::H1V2Convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - uint8 *d0 = m_pScan_line_0; - uint8 *d1 = m_pScan_line_1; - uint8 *y; - uint8 *c; - - if (row < 8) - y = m_pSample_buf + row * 8; - else - y = m_pSample_buf + 64*1 + (row & 7) * 8; - - c = m_pSample_buf + 64*2 + (row >> 1) * 8; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - for (int j = 0; j < 8; j++) - { - int cb = c[0+j]; - int cr = c[64+j]; - - int rc = m_crr[cr]; - int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); - int bc = m_cbb[cb]; - - int yy = y[j]; - d0[0] = clamp(yy+rc); - d0[1] = clamp(yy+gc); - d0[2] = clamp(yy+bc); - d0[3] = 255; - - yy = y[8+j]; - d1[0] = clamp(yy+rc); - d1[1] = clamp(yy+gc); - d1[2] = clamp(yy+bc); - d1[3] = 255; - - d0 += 4; - d1 += 4; - } - - y += 64*4; - c += 64*4; - } -} - -// YCbCr H2V2 (2x2:1:1, 6 m_blocks per MCU) to RGB -void jpeg_decoder::H2V2Convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - uint8 *d0 = m_pScan_line_0; - uint8 *d1 = m_pScan_line_1; - uint8 *y; - uint8 *c; - - if (row < 8) - y = m_pSample_buf + row * 8; - else - y = m_pSample_buf + 64*2 + (row & 7) * 8; - - c = m_pSample_buf + 64*4 + (row >> 1) * 8; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - for (int l = 0; l < 2; l++) - { - for (int j = 0; j < 8; j += 2) - { - int cb = c[0]; - int cr = c[64]; + // Create a few tables that allow us to quickly convert YCbCr to RGB. + void jpeg_decoder::create_look_ups() + { + for (int i = 0; i <= 255; i++) + { + int k = i - 128; + m_crr[i] = (FIX(1.40200f) * k + ONE_HALF) >> SCALEBITS; + m_cbb[i] = (FIX(1.77200f) * k + ONE_HALF) >> SCALEBITS; + m_crg[i] = (-FIX(0.71414f)) * k; + m_cbg[i] = (-FIX(0.34414f)) * k + ONE_HALF; + } + } + + // This method throws back into the stream any bytes that where read + // into the bit buffer during initial marker scanning. + void jpeg_decoder::fix_in_buffer() + { + // In case any 0xFF's where pulled into the buffer during marker scanning. + assert((m_bits_left & 7) == 0); + + if (m_bits_left == 16) + stuff_char((uint8)(m_bit_buf & 0xFF)); + + if (m_bits_left >= 8) + stuff_char((uint8)((m_bit_buf >> 8) & 0xFF)); + + stuff_char((uint8)((m_bit_buf >> 16) & 0xFF)); + stuff_char((uint8)((m_bit_buf >> 24) & 0xFF)); + + m_bits_left = 16; + get_bits_no_markers(16); + get_bits_no_markers(16); + } + + void jpeg_decoder::transform_mcu(int mcu_row) + { + jpgd_block_coeff_t* pSrc_ptr = m_pMCU_coefficients; + if (mcu_row * m_blocks_per_mcu >= m_max_blocks_per_row) + stop_decoding(JPGD_DECODE_ERROR); + + uint8* pDst_ptr = m_pSample_buf + mcu_row * m_blocks_per_mcu * 64; + + for (int mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) + { + idct(pSrc_ptr, pDst_ptr, m_mcu_block_max_zag[mcu_block], ((m_flags & cFlagDisableSIMD) == 0) && m_has_sse2); + pSrc_ptr += 64; + pDst_ptr += 64; + } + } + + // Loads and dequantizes the next row of (already decoded) coefficients. + // Progressive images only. + void jpeg_decoder::load_next_row() + { + int i; + jpgd_block_coeff_t* p; + jpgd_quant_t* q; + int mcu_row, mcu_block, row_block = 0; + int component_num, component_id; + int block_x_mcu[JPGD_MAX_COMPONENTS]; + + memset(block_x_mcu, 0, JPGD_MAX_COMPONENTS * sizeof(int)); + + for (mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) + { + int block_x_mcu_ofs = 0, block_y_mcu_ofs = 0; + + for (mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) + { + component_id = m_mcu_org[mcu_block]; + if (m_comp_quant[component_id] >= JPGD_MAX_QUANT_TABLES) + stop_decoding(JPGD_DECODE_ERROR); + + q = m_quant[m_comp_quant[component_id]]; + + p = m_pMCU_coefficients + 64 * mcu_block; + + jpgd_block_coeff_t* pAC = coeff_buf_getp(m_ac_coeffs[component_id], block_x_mcu[component_id] + block_x_mcu_ofs, m_block_y_mcu[component_id] + block_y_mcu_ofs); + jpgd_block_coeff_t* pDC = coeff_buf_getp(m_dc_coeffs[component_id], block_x_mcu[component_id] + block_x_mcu_ofs, m_block_y_mcu[component_id] + block_y_mcu_ofs); + p[0] = pDC[0]; + memcpy(&p[1], &pAC[1], 63 * sizeof(jpgd_block_coeff_t)); + + for (i = 63; i > 0; i--) + if (p[g_ZAG[i]]) + break; + + m_mcu_block_max_zag[mcu_block] = i + 1; + + for (; i >= 0; i--) + if (p[g_ZAG[i]]) + p[g_ZAG[i]] = static_cast<jpgd_block_coeff_t>(p[g_ZAG[i]] * q[i]); + + row_block++; + + if (m_comps_in_scan == 1) + block_x_mcu[component_id]++; + else + { + if (++block_x_mcu_ofs == m_comp_h_samp[component_id]) + { + block_x_mcu_ofs = 0; + + if (++block_y_mcu_ofs == m_comp_v_samp[component_id]) + { + block_y_mcu_ofs = 0; + + block_x_mcu[component_id] += m_comp_h_samp[component_id]; + } + } + } + } + + transform_mcu(mcu_row); + } + + if (m_comps_in_scan == 1) + m_block_y_mcu[m_comp_list[0]]++; + else + { + for (component_num = 0; component_num < m_comps_in_scan; component_num++) + { + component_id = m_comp_list[component_num]; + + m_block_y_mcu[component_id] += m_comp_v_samp[component_id]; + } + } + } + + // Restart interval processing. + void jpeg_decoder::process_restart() + { + int i; + int c = 0; + + // Align to a byte boundry + // FIXME: Is this really necessary? get_bits_no_markers() never reads in markers! + //get_bits_no_markers(m_bits_left & 7); + + // Let's scan a little bit to find the marker, but not _too_ far. + // 1536 is a "fudge factor" that determines how much to scan. + for (i = 1536; i > 0; i--) + if (get_char() == 0xFF) + break; + + if (i == 0) + stop_decoding(JPGD_BAD_RESTART_MARKER); + + for (; i > 0; i--) + if ((c = get_char()) != 0xFF) + break; + + if (i == 0) + stop_decoding(JPGD_BAD_RESTART_MARKER); + + // Is it the expected marker? If not, something bad happened. + if (c != (m_next_restart_num + M_RST0)) + stop_decoding(JPGD_BAD_RESTART_MARKER); + + // Reset each component's DC prediction values. + memset(&m_last_dc_val, 0, m_comps_in_frame * sizeof(uint)); + + m_eob_run = 0; + + m_restarts_left = m_restart_interval; + + m_next_restart_num = (m_next_restart_num + 1) & 7; + + // Get the bit buffer going again... + + m_bits_left = 16; + get_bits_no_markers(16); + get_bits_no_markers(16); + } + + static inline int dequantize_ac(int c, int q) { c *= q; return c; } + + // Decodes and dequantizes the next row of coefficients. + void jpeg_decoder::decode_next_row() + { + int row_block = 0; + + for (int mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) + { + if ((m_restart_interval) && (m_restarts_left == 0)) + process_restart(); + + jpgd_block_coeff_t* p = m_pMCU_coefficients; + for (int mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++, p += 64) + { + int component_id = m_mcu_org[mcu_block]; + if (m_comp_quant[component_id] >= JPGD_MAX_QUANT_TABLES) + stop_decoding(JPGD_DECODE_ERROR); + + jpgd_quant_t* q = m_quant[m_comp_quant[component_id]]; + + int r, s; + s = huff_decode(m_pHuff_tabs[m_comp_dc_tab[component_id]], r); + if (s >= 16) + stop_decoding(JPGD_DECODE_ERROR); + + s = JPGD_HUFF_EXTEND(r, s); + + m_last_dc_val[component_id] = (s += m_last_dc_val[component_id]); + + p[0] = static_cast<jpgd_block_coeff_t>(s * q[0]); + + int prev_num_set = m_mcu_block_max_zag[mcu_block]; + + huff_tables* pH = m_pHuff_tabs[m_comp_ac_tab[component_id]]; + + int k; + for (k = 1; k < 64; k++) + { + int extra_bits; + s = huff_decode(pH, extra_bits); + + r = s >> 4; + s &= 15; + + if (s) + { + if (r) + { + if ((k + r) > 63) + stop_decoding(JPGD_DECODE_ERROR); + + if (k < prev_num_set) + { + int n = JPGD_MIN(r, prev_num_set - k); + int kt = k; + while (n--) + p[g_ZAG[kt++]] = 0; + } + + k += r; + } + + s = JPGD_HUFF_EXTEND(extra_bits, s); + + if (k >= 64) + stop_decoding(JPGD_DECODE_ERROR); + + p[g_ZAG[k]] = static_cast<jpgd_block_coeff_t>(dequantize_ac(s, q[k])); //s * q[k]; + } + else + { + if (r == 15) + { + if ((k + 16) > 64) + stop_decoding(JPGD_DECODE_ERROR); + + if (k < prev_num_set) + { + int n = JPGD_MIN(16, prev_num_set - k); + int kt = k; + while (n--) + { + if (kt > 63) + stop_decoding(JPGD_DECODE_ERROR); + p[g_ZAG[kt++]] = 0; + } + } + + k += 16 - 1; // - 1 because the loop counter is k + + if (p[g_ZAG[k & 63]] != 0) + stop_decoding(JPGD_DECODE_ERROR); + } + else + break; + } + } + + if (k < prev_num_set) + { + int kt = k; + while (kt < prev_num_set) + p[g_ZAG[kt++]] = 0; + } + + m_mcu_block_max_zag[mcu_block] = k; + + row_block++; + } + + transform_mcu(mcu_row); + + m_restarts_left--; + } + } + + // YCbCr H1V1 (1x1:1:1, 3 m_blocks per MCU) to RGB + void jpeg_decoder::H1V1Convert() + { + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d = m_pScan_line_0; + uint8* s = m_pSample_buf + row * 8; + + for (int i = m_max_mcus_per_row; i > 0; i--) + { + for (int j = 0; j < 8; j++) + { + int y = s[j]; + int cb = s[64 + j]; + int cr = s[128 + j]; + + d[0] = clamp(y + m_crr[cr]); + d[1] = clamp(y + ((m_crg[cr] + m_cbg[cb]) >> 16)); + d[2] = clamp(y + m_cbb[cb]); + d[3] = 255; + + d += 4; + } + + s += 64 * 3; + } + } + + // YCbCr H2V1 (2x1:1:1, 4 m_blocks per MCU) to RGB + void jpeg_decoder::H2V1Convert() + { + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d0 = m_pScan_line_0; + uint8* y = m_pSample_buf + row * 8; + uint8* c = m_pSample_buf + 2 * 64 + row * 8; + + for (int i = m_max_mcus_per_row; i > 0; i--) + { + for (int l = 0; l < 2; l++) + { + for (int j = 0; j < 4; j++) + { + int cb = c[0]; + int cr = c[64]; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + int yy = y[j << 1]; + d0[0] = clamp(yy + rc); + d0[1] = clamp(yy + gc); + d0[2] = clamp(yy + bc); + d0[3] = 255; + + yy = y[(j << 1) + 1]; + d0[4] = clamp(yy + rc); + d0[5] = clamp(yy + gc); + d0[6] = clamp(yy + bc); + d0[7] = 255; + + d0 += 8; + + c++; + } + y += 64; + } + + y += 64 * 4 - 64 * 2; + c += 64 * 4 - 8; + } + } + + // YCbCr H2V1 (2x1:1:1, 4 m_blocks per MCU) to RGB + void jpeg_decoder::H2V1ConvertFiltered() + { + const uint BLOCKS_PER_MCU = 4; + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d0 = m_pScan_line_0; + + const int half_image_x_size = (m_image_x_size >> 1) - 1; + const int row_x8 = row * 8; + + for (int x = 0; x < m_image_x_size; x++) + { + int y = m_pSample_buf[check_sample_buf_ofs((x >> 4) * BLOCKS_PER_MCU * 64 + ((x & 8) ? 64 : 0) + (x & 7) + row_x8)]; + + int c_x0 = (x - 1) >> 1; + int c_x1 = JPGD_MIN(c_x0 + 1, half_image_x_size); + c_x0 = JPGD_MAX(c_x0, 0); + + int a = (c_x0 >> 3) * BLOCKS_PER_MCU * 64 + (c_x0 & 7) + row_x8 + 128; + int cb0 = m_pSample_buf[check_sample_buf_ofs(a)]; + int cr0 = m_pSample_buf[check_sample_buf_ofs(a + 64)]; + + int b = (c_x1 >> 3) * BLOCKS_PER_MCU * 64 + (c_x1 & 7) + row_x8 + 128; + int cb1 = m_pSample_buf[check_sample_buf_ofs(b)]; + int cr1 = m_pSample_buf[check_sample_buf_ofs(b + 64)]; + + int w0 = (x & 1) ? 3 : 1; + int w1 = (x & 1) ? 1 : 3; + + int cb = (cb0 * w0 + cb1 * w1 + 2) >> 2; + int cr = (cr0 * w0 + cr1 * w1 + 2) >> 2; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d0[0] = clamp(y + rc); + d0[1] = clamp(y + gc); + d0[2] = clamp(y + bc); + d0[3] = 255; + + d0 += 4; + } + } + + // YCbCr H2V1 (1x2:1:1, 4 m_blocks per MCU) to RGB + void jpeg_decoder::H1V2Convert() + { + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d0 = m_pScan_line_0; + uint8* d1 = m_pScan_line_1; + uint8* y; + uint8* c; + + if (row < 8) + y = m_pSample_buf + row * 8; + else + y = m_pSample_buf + 64 * 1 + (row & 7) * 8; + + c = m_pSample_buf + 64 * 2 + (row >> 1) * 8; + + for (int i = m_max_mcus_per_row; i > 0; i--) + { + for (int j = 0; j < 8; j++) + { + int cb = c[0 + j]; + int cr = c[64 + j]; int rc = m_crr[cr]; int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); int bc = m_cbb[cb]; int yy = y[j]; - d0[0] = clamp(yy+rc); - d0[1] = clamp(yy+gc); - d0[2] = clamp(yy+bc); + d0[0] = clamp(yy + rc); + d0[1] = clamp(yy + gc); + d0[2] = clamp(yy + bc); d0[3] = 255; - yy = y[j+1]; - d0[4] = clamp(yy+rc); - d0[5] = clamp(yy+gc); - d0[6] = clamp(yy+bc); - d0[7] = 255; - - yy = y[j+8]; - d1[0] = clamp(yy+rc); - d1[1] = clamp(yy+gc); - d1[2] = clamp(yy+bc); + yy = y[8 + j]; + d1[0] = clamp(yy + rc); + d1[1] = clamp(yy + gc); + d1[2] = clamp(yy + bc); d1[3] = 255; - yy = y[j+8+1]; - d1[4] = clamp(yy+rc); - d1[5] = clamp(yy+gc); - d1[6] = clamp(yy+bc); - d1[7] = 255; + d0 += 4; + d1 += 4; + } + + y += 64 * 4; + c += 64 * 4; + } + } + + // YCbCr H2V1 (1x2:1:1, 4 m_blocks per MCU) to RGB + void jpeg_decoder::H1V2ConvertFiltered() + { + const uint BLOCKS_PER_MCU = 4; + int y = m_image_y_size - m_total_lines_left; + int row = y & 15; + + const int half_image_y_size = (m_image_y_size >> 1) - 1; + + uint8* d0 = m_pScan_line_0; + + const int w0 = (row & 1) ? 3 : 1; + const int w1 = (row & 1) ? 1 : 3; + + int c_y0 = (y - 1) >> 1; + int c_y1 = JPGD_MIN(c_y0 + 1, half_image_y_size); + + const uint8_t* p_YSamples = m_pSample_buf; + const uint8_t* p_C0Samples = m_pSample_buf; + if ((c_y0 >= 0) && (((row & 15) == 0) || ((row & 15) == 15)) && (m_total_lines_left > 1)) + { + assert(y > 0); + assert(m_sample_buf_prev_valid); + + if ((row & 15) == 15) + p_YSamples = m_pSample_buf_prev; + + p_C0Samples = m_pSample_buf_prev; + } + + const int y_sample_base_ofs = ((row & 8) ? 64 : 0) + (row & 7) * 8; + const int y0_base = (c_y0 & 7) * 8 + 128; + const int y1_base = (c_y1 & 7) * 8 + 128; + + for (int x = 0; x < m_image_x_size; x++) + { + const int base_ofs = (x >> 3) * BLOCKS_PER_MCU * 64 + (x & 7); + + int y_sample = p_YSamples[check_sample_buf_ofs(base_ofs + y_sample_base_ofs)]; + + int a = base_ofs + y0_base; + int cb0_sample = p_C0Samples[check_sample_buf_ofs(a)]; + int cr0_sample = p_C0Samples[check_sample_buf_ofs(a + 64)]; + + int b = base_ofs + y1_base; + int cb1_sample = m_pSample_buf[check_sample_buf_ofs(b)]; + int cr1_sample = m_pSample_buf[check_sample_buf_ofs(b + 64)]; + + int cb = (cb0_sample * w0 + cb1_sample * w1 + 2) >> 2; + int cr = (cr0_sample * w0 + cr1_sample * w1 + 2) >> 2; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d0[0] = clamp(y_sample + rc); + d0[1] = clamp(y_sample + gc); + d0[2] = clamp(y_sample + bc); + d0[3] = 255; + + d0 += 4; + } + } + + // YCbCr H2V2 (2x2:1:1, 6 m_blocks per MCU) to RGB + void jpeg_decoder::H2V2Convert() + { + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d0 = m_pScan_line_0; + uint8* d1 = m_pScan_line_1; + uint8* y; + uint8* c; - d0 += 8; - d1 += 8; + if (row < 8) + y = m_pSample_buf + row * 8; + else + y = m_pSample_buf + 64 * 2 + (row & 7) * 8; - c++; + c = m_pSample_buf + 64 * 4 + (row >> 1) * 8; + + for (int i = m_max_mcus_per_row; i > 0; i--) + { + for (int l = 0; l < 2; l++) + { + for (int j = 0; j < 8; j += 2) + { + int cb = c[0]; + int cr = c[64]; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + int yy = y[j]; + d0[0] = clamp(yy + rc); + d0[1] = clamp(yy + gc); + d0[2] = clamp(yy + bc); + d0[3] = 255; + + yy = y[j + 1]; + d0[4] = clamp(yy + rc); + d0[5] = clamp(yy + gc); + d0[6] = clamp(yy + bc); + d0[7] = 255; + + yy = y[j + 8]; + d1[0] = clamp(yy + rc); + d1[1] = clamp(yy + gc); + d1[2] = clamp(yy + bc); + d1[3] = 255; + + yy = y[j + 8 + 1]; + d1[4] = clamp(yy + rc); + d1[5] = clamp(yy + gc); + d1[6] = clamp(yy + bc); + d1[7] = 255; + + d0 += 8; + d1 += 8; + + c++; + } + y += 64; } - y += 64; - } - - y += 64*6 - 64*2; - c += 64*6 - 8; - } -} - -// Y (1 block per MCU) to 8-bit grayscale -void jpeg_decoder::gray_convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - uint8 *d = m_pScan_line_0; - uint8 *s = m_pSample_buf + row * 8; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - *(uint *)d = *(uint *)s; - *(uint *)(&d[4]) = *(uint *)(&s[4]); - - s += 64; - d += 8; - } -} - -void jpeg_decoder::expanded_convert() -{ - int row = m_max_mcu_y_size - m_mcu_lines_left; - - uint8* Py = m_pSample_buf + (row / 8) * 64 * m_comp_h_samp[0] + (row & 7) * 8; - - uint8* d = m_pScan_line_0; - - for (int i = m_max_mcus_per_row; i > 0; i--) - { - for (int k = 0; k < m_max_mcu_x_size; k += 8) - { - const int Y_ofs = k * 8; - const int Cb_ofs = Y_ofs + 64 * m_expanded_blocks_per_component; - const int Cr_ofs = Y_ofs + 64 * m_expanded_blocks_per_component * 2; - for (int j = 0; j < 8; j++) - { - int y = Py[Y_ofs + j]; - int cb = Py[Cb_ofs + j]; - int cr = Py[Cr_ofs + j]; - - d[0] = clamp(y + m_crr[cr]); - d[1] = clamp(y + ((m_crg[cr] + m_cbg[cb]) >> 16)); - d[2] = clamp(y + m_cbb[cb]); - d[3] = 255; - - d += 4; - } - } - - Py += 64 * m_expanded_blocks_per_mcu; - } -} - -// Find end of image (EOI) marker, so we can return to the user the exact size of the input stream. -void jpeg_decoder::find_eoi() -{ - if (!m_progressive_flag) - { - // Attempt to read the EOI marker. - //get_bits_no_markers(m_bits_left & 7); - - // Prime the bit buffer - m_bits_left = 16; - get_bits(16); - get_bits(16); - - // The next marker _should_ be EOI - process_markers(); - } - - m_total_bytes_read -= m_in_buf_left; -} - -int jpeg_decoder::decode(const void** pScan_line, uint* pScan_line_len) -{ - if ((m_error_code) || (!m_ready_flag)) - return JPGD_FAILED; - - if (m_total_lines_left == 0) - return JPGD_DONE; - - if (m_mcu_lines_left == 0) - { - if (setjmp(m_jmp_state)) - return JPGD_FAILED; - - if (m_progressive_flag) - load_next_row(); - else - decode_next_row(); - - // Find the EOI marker if that was the last row. - if (m_total_lines_left <= m_max_mcu_y_size) - find_eoi(); - - m_mcu_lines_left = m_max_mcu_y_size; - } - - if (m_freq_domain_chroma_upsample) - { - expanded_convert(); - *pScan_line = m_pScan_line_0; - } - else - { - switch (m_scan_type) - { - case JPGD_YH2V2: - { - if ((m_mcu_lines_left & 1) == 0) - { - H2V2Convert(); - *pScan_line = m_pScan_line_0; - } - else - *pScan_line = m_pScan_line_1; - - break; - } - case JPGD_YH2V1: - { - H2V1Convert(); - *pScan_line = m_pScan_line_0; - break; - } - case JPGD_YH1V2: - { - if ((m_mcu_lines_left & 1) == 0) - { - H1V2Convert(); - *pScan_line = m_pScan_line_0; - } - else - *pScan_line = m_pScan_line_1; - - break; - } - case JPGD_YH1V1: - { - H1V1Convert(); - *pScan_line = m_pScan_line_0; - break; - } - case JPGD_GRAYSCALE: - { - gray_convert(); - *pScan_line = m_pScan_line_0; - - break; - } - } - } - - *pScan_line_len = m_real_dest_bytes_per_scan_line; - - m_mcu_lines_left--; - m_total_lines_left--; - - return JPGD_SUCCESS; -} - -// Creates the tables needed for efficient Huffman decoding. -void jpeg_decoder::make_huff_table(int index, huff_tables *pH) -{ - int p, i, l, si; - uint8 huffsize[257]; - uint huffcode[257]; - uint code; - uint subtree; - int code_size; - int lastp; - int nextfreeentry; - int currententry; - - pH->ac_table = m_huff_ac[index] != 0; - - p = 0; - - for (l = 1; l <= 16; l++) - { - for (i = 1; i <= m_huff_num[index][l]; i++) - { - JPGD_ASSERT(p < 257); - huffsize[p++] = static_cast<uint8>(l); - } - } - - huffsize[p] = 0; - - lastp = p; - - code = 0; - si = huffsize[0]; - p = 0; - - while (huffsize[p]) - { - while (huffsize[p] == si) - { - JPGD_ASSERT(p < 257); - huffcode[p++] = code; - code++; - } - - code <<= 1; - si++; - } - - memset(pH->look_up, 0, sizeof(pH->look_up)); - memset(pH->look_up2, 0, sizeof(pH->look_up2)); - memset(pH->tree, 0, sizeof(pH->tree)); - memset(pH->code_size, 0, sizeof(pH->code_size)); - - nextfreeentry = -1; - - p = 0; - - while (p < lastp) - { - i = m_huff_val[index][p]; - code = huffcode[p]; - code_size = huffsize[p]; - - pH->code_size[i] = static_cast<uint8>(code_size); - - if (code_size <= 8) - { - code <<= (8 - code_size); - - for (l = 1 << (8 - code_size); l > 0; l--) - { - JPGD_ASSERT(i < JPGD_HUFF_CODE_SIZE_MAX_LENGTH); - JPGD_ASSERT(code < JPGD_HUFF_CODE_SIZE_MAX_LENGTH); - - pH->look_up[code] = i; - - bool has_extrabits = false; - int extra_bits = 0; - int num_extra_bits = i & 15; - - int bits_to_fetch = code_size; - if (num_extra_bits) - { - int total_codesize = code_size + num_extra_bits; - if (total_codesize <= 8) - { - has_extrabits = true; - extra_bits = ((1 << num_extra_bits) - 1) & (code >> (8 - total_codesize)); - JPGD_ASSERT(extra_bits <= 0x7FFF); - bits_to_fetch += num_extra_bits; - } - } - - if (!has_extrabits) - pH->look_up2[code] = i | (bits_to_fetch << 8); - else - pH->look_up2[code] = i | 0x8000 | (extra_bits << 16) | (bits_to_fetch << 8); - - code++; - } - } - else - { - subtree = (code >> (code_size - 8)) & 0xFF; - - currententry = pH->look_up[subtree]; - - if (currententry == 0) - { - pH->look_up[subtree] = currententry = nextfreeentry; - pH->look_up2[subtree] = currententry = nextfreeentry; - - nextfreeentry -= 2; - } - - code <<= (16 - (code_size - 8)); - - for (l = code_size; l > 9; l--) - { - if ((code & 0x8000) == 0) - currententry--; - - unsigned int idx = -currententry - 1; - JPGD_ASSERT(idx < JPGD_HUFF_TREE_MAX_LENGTH); - if (pH->tree[idx] == 0) - { - pH->tree[idx] = nextfreeentry; - - currententry = nextfreeentry; - - nextfreeentry -= 2; - } - else { - currententry = pH->tree[idx]; - } - - code <<= 1; - } - - if ((code & 0x8000) == 0) - currententry--; - - pH->tree[-currententry - 1] = i; - } - - p++; - } -} - -// Verifies the quantization tables needed for this scan are available. -void jpeg_decoder::check_quant_tables() -{ - for (int i = 0; i < m_comps_in_scan; i++) - if (m_quant[m_comp_quant[m_comp_list[i]]] == NULL) - stop_decoding(JPGD_UNDEFINED_QUANT_TABLE); -} - -// Verifies that all the Huffman tables needed for this scan are available. -void jpeg_decoder::check_huff_tables() -{ - for (int i = 0; i < m_comps_in_scan; i++) - { - if ((m_spectral_start == 0) && (m_huff_num[m_comp_dc_tab[m_comp_list[i]]] == NULL)) - stop_decoding(JPGD_UNDEFINED_HUFF_TABLE); - - if ((m_spectral_end > 0) && (m_huff_num[m_comp_ac_tab[m_comp_list[i]]] == NULL)) - stop_decoding(JPGD_UNDEFINED_HUFF_TABLE); - } - - for (int i = 0; i < JPGD_MAX_HUFF_TABLES; i++) - if (m_huff_num[i]) - { - if (!m_pHuff_tabs[i]) - m_pHuff_tabs[i] = (huff_tables *)alloc(sizeof(huff_tables)); - - make_huff_table(i, m_pHuff_tabs[i]); - } -} - -// Determines the component order inside each MCU. -// Also calcs how many MCU's are on each row, etc. -void jpeg_decoder::calc_mcu_block_order() -{ - int component_num, component_id; - int max_h_samp = 0, max_v_samp = 0; - - for (component_id = 0; component_id < m_comps_in_frame; component_id++) - { - if (m_comp_h_samp[component_id] > max_h_samp) - max_h_samp = m_comp_h_samp[component_id]; - - if (m_comp_v_samp[component_id] > max_v_samp) - max_v_samp = m_comp_v_samp[component_id]; - } - - for (component_id = 0; component_id < m_comps_in_frame; component_id++) - { - m_comp_h_blocks[component_id] = ((((m_image_x_size * m_comp_h_samp[component_id]) + (max_h_samp - 1)) / max_h_samp) + 7) / 8; - m_comp_v_blocks[component_id] = ((((m_image_y_size * m_comp_v_samp[component_id]) + (max_v_samp - 1)) / max_v_samp) + 7) / 8; - } - - if (m_comps_in_scan == 1) - { - m_mcus_per_row = m_comp_h_blocks[m_comp_list[0]]; - m_mcus_per_col = m_comp_v_blocks[m_comp_list[0]]; - } - else - { - m_mcus_per_row = (((m_image_x_size + 7) / 8) + (max_h_samp - 1)) / max_h_samp; - m_mcus_per_col = (((m_image_y_size + 7) / 8) + (max_v_samp - 1)) / max_v_samp; - } - - if (m_comps_in_scan == 1) - { - m_mcu_org[0] = m_comp_list[0]; - - m_blocks_per_mcu = 1; - } - else - { - m_blocks_per_mcu = 0; - - for (component_num = 0; component_num < m_comps_in_scan; component_num++) - { - int num_blocks; - - component_id = m_comp_list[component_num]; - - num_blocks = m_comp_h_samp[component_id] * m_comp_v_samp[component_id]; - - while (num_blocks--) - m_mcu_org[m_blocks_per_mcu++] = component_id; - } - } -} - -// Starts a new scan. -int jpeg_decoder::init_scan() -{ - if (!locate_sos_marker()) - return JPGD_FALSE; - - calc_mcu_block_order(); - - check_huff_tables(); - - check_quant_tables(); - - memset(m_last_dc_val, 0, m_comps_in_frame * sizeof(uint)); - - m_eob_run = 0; - - if (m_restart_interval) - { - m_restarts_left = m_restart_interval; - m_next_restart_num = 0; - } - - fix_in_buffer(); - - return JPGD_TRUE; -} - -// Starts a frame. Determines if the number of components or sampling factors -// are supported. -void jpeg_decoder::init_frame() -{ - int i; - - if (m_comps_in_frame == 1) - { - if ((m_comp_h_samp[0] != 1) || (m_comp_v_samp[0] != 1)) - stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); - - m_scan_type = JPGD_GRAYSCALE; - m_max_blocks_per_mcu = 1; - m_max_mcu_x_size = 8; - m_max_mcu_y_size = 8; - } - else if (m_comps_in_frame == 3) - { - if ( ((m_comp_h_samp[1] != 1) || (m_comp_v_samp[1] != 1)) || - ((m_comp_h_samp[2] != 1) || (m_comp_v_samp[2] != 1)) ) - stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); - - if ((m_comp_h_samp[0] == 1) && (m_comp_v_samp[0] == 1)) - { - m_scan_type = JPGD_YH1V1; - - m_max_blocks_per_mcu = 3; - m_max_mcu_x_size = 8; - m_max_mcu_y_size = 8; - } - else if ((m_comp_h_samp[0] == 2) && (m_comp_v_samp[0] == 1)) - { - m_scan_type = JPGD_YH2V1; - m_max_blocks_per_mcu = 4; - m_max_mcu_x_size = 16; - m_max_mcu_y_size = 8; - } - else if ((m_comp_h_samp[0] == 1) && (m_comp_v_samp[0] == 2)) - { - m_scan_type = JPGD_YH1V2; - m_max_blocks_per_mcu = 4; - m_max_mcu_x_size = 8; - m_max_mcu_y_size = 16; - } - else if ((m_comp_h_samp[0] == 2) && (m_comp_v_samp[0] == 2)) - { - m_scan_type = JPGD_YH2V2; - m_max_blocks_per_mcu = 6; - m_max_mcu_x_size = 16; - m_max_mcu_y_size = 16; - } - else - stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); - } - else - stop_decoding(JPGD_UNSUPPORTED_COLORSPACE); - - m_max_mcus_per_row = (m_image_x_size + (m_max_mcu_x_size - 1)) / m_max_mcu_x_size; - m_max_mcus_per_col = (m_image_y_size + (m_max_mcu_y_size - 1)) / m_max_mcu_y_size; - - // These values are for the *destination* pixels: after conversion. - if (m_scan_type == JPGD_GRAYSCALE) - m_dest_bytes_per_pixel = 1; - else - m_dest_bytes_per_pixel = 4; - - m_dest_bytes_per_scan_line = ((m_image_x_size + 15) & 0xFFF0) * m_dest_bytes_per_pixel; - - m_real_dest_bytes_per_scan_line = (m_image_x_size * m_dest_bytes_per_pixel); - - // Initialize two scan line buffers. - m_pScan_line_0 = (uint8 *)alloc(m_dest_bytes_per_scan_line, true); - if ((m_scan_type == JPGD_YH1V2) || (m_scan_type == JPGD_YH2V2)) - m_pScan_line_1 = (uint8 *)alloc(m_dest_bytes_per_scan_line, true); - - m_max_blocks_per_row = m_max_mcus_per_row * m_max_blocks_per_mcu; - - // Should never happen - if (m_max_blocks_per_row > JPGD_MAX_BLOCKS_PER_ROW) - stop_decoding(JPGD_ASSERTION_ERROR); - - // Allocate the coefficient buffer, enough for one MCU - m_pMCU_coefficients = (jpgd_block_t*)alloc(m_max_blocks_per_mcu * 64 * sizeof(jpgd_block_t)); - - for (i = 0; i < m_max_blocks_per_mcu; i++) - m_mcu_block_max_zag[i] = 64; - - m_expanded_blocks_per_component = m_comp_h_samp[0] * m_comp_v_samp[0]; - m_expanded_blocks_per_mcu = m_expanded_blocks_per_component * m_comps_in_frame; - m_expanded_blocks_per_row = m_max_mcus_per_row * m_expanded_blocks_per_mcu; - // Freq. domain chroma upsampling is only supported for H2V2 subsampling factor (the most common one I've seen). - m_freq_domain_chroma_upsample = false; -#if JPGD_SUPPORT_FREQ_DOMAIN_UPSAMPLING - m_freq_domain_chroma_upsample = (m_expanded_blocks_per_mcu == 4*3); -#endif - if (m_freq_domain_chroma_upsample) - m_pSample_buf = (uint8 *)alloc(m_expanded_blocks_per_row * 64); - else - m_pSample_buf = (uint8 *)alloc(m_max_blocks_per_row * 64); - - m_total_lines_left = m_image_y_size; - - m_mcu_lines_left = 0; - - create_look_ups(); -} - -// The coeff_buf series of methods originally stored the coefficients -// into a "virtual" file which was located in EMS, XMS, or a disk file. A cache -// was used to make this process more efficient. Now, we can store the entire -// thing in RAM. -jpeg_decoder::coeff_buf* jpeg_decoder::coeff_buf_open(int block_num_x, int block_num_y, int block_len_x, int block_len_y) -{ - coeff_buf* cb = (coeff_buf*)alloc(sizeof(coeff_buf)); - - cb->block_num_x = block_num_x; - cb->block_num_y = block_num_y; - cb->block_len_x = block_len_x; - cb->block_len_y = block_len_y; - cb->block_size = (block_len_x * block_len_y) * sizeof(jpgd_block_t); - cb->pData = (uint8 *)alloc(cb->block_size * block_num_x * block_num_y, true); - return cb; -} - -inline jpgd_block_t *jpeg_decoder::coeff_buf_getp(coeff_buf *cb, int block_x, int block_y) -{ - JPGD_ASSERT((block_x < cb->block_num_x) && (block_y < cb->block_num_y)); - return (jpgd_block_t *)(cb->pData + block_x * cb->block_size + block_y * (cb->block_size * cb->block_num_x)); -} - -// The following methods decode the various types of m_blocks encountered -// in progressively encoded images. -void jpeg_decoder::decode_block_dc_first(jpeg_decoder *pD, int component_id, int block_x, int block_y) -{ - int s, r; - jpgd_block_t *p = pD->coeff_buf_getp(pD->m_dc_coeffs[component_id], block_x, block_y); - - if ((s = pD->huff_decode(pD->m_pHuff_tabs[pD->m_comp_dc_tab[component_id]])) != 0) - { - r = pD->get_bits_no_markers(s); - s = JPGD_HUFF_EXTEND(r, s); - } - - pD->m_last_dc_val[component_id] = (s += pD->m_last_dc_val[component_id]); - - p[0] = static_cast<jpgd_block_t>(s << pD->m_successive_low); -} - -void jpeg_decoder::decode_block_dc_refine(jpeg_decoder *pD, int component_id, int block_x, int block_y) -{ - if (pD->get_bits_no_markers(1)) - { - jpgd_block_t *p = pD->coeff_buf_getp(pD->m_dc_coeffs[component_id], block_x, block_y); - - p[0] |= (1 << pD->m_successive_low); - } -} - -void jpeg_decoder::decode_block_ac_first(jpeg_decoder *pD, int component_id, int block_x, int block_y) -{ - int k, s, r; - - if (pD->m_eob_run) - { - pD->m_eob_run--; - return; - } - - jpgd_block_t *p = pD->coeff_buf_getp(pD->m_ac_coeffs[component_id], block_x, block_y); - - for (k = pD->m_spectral_start; k <= pD->m_spectral_end; k++) - { - unsigned int idx = pD->m_comp_ac_tab[component_id]; - JPGD_ASSERT(idx < JPGD_MAX_HUFF_TABLES); - s = pD->huff_decode(pD->m_pHuff_tabs[idx]); - - r = s >> 4; - s &= 15; - - if (s) - { - if ((k += r) > 63) - pD->stop_decoding(JPGD_DECODE_ERROR); - - r = pD->get_bits_no_markers(s); - s = JPGD_HUFF_EXTEND(r, s); - - p[g_ZAG[k]] = static_cast<jpgd_block_t>(s << pD->m_successive_low); - } - else - { - if (r == 15) - { - if ((k += 15) > 63) - pD->stop_decoding(JPGD_DECODE_ERROR); - } - else - { - pD->m_eob_run = 1 << r; - - if (r) - pD->m_eob_run += pD->get_bits_no_markers(r); - - pD->m_eob_run--; - - break; - } - } - } -} - -void jpeg_decoder::decode_block_ac_refine(jpeg_decoder *pD, int component_id, int block_x, int block_y) -{ - int s, k, r; - int p1 = 1 << pD->m_successive_low; - int m1 = (-1) << pD->m_successive_low; - jpgd_block_t *p = pD->coeff_buf_getp(pD->m_ac_coeffs[component_id], block_x, block_y); - JPGD_ASSERT(pD->m_spectral_end <= 63); - - k = pD->m_spectral_start; - - if (pD->m_eob_run == 0) - { - for ( ; k <= pD->m_spectral_end; k++) - { - unsigned int idx = pD->m_comp_ac_tab[component_id]; - JPGD_ASSERT(idx < JPGD_MAX_HUFF_TABLES); - s = pD->huff_decode(pD->m_pHuff_tabs[idx]); - - r = s >> 4; - s &= 15; - - if (s) - { - if (s != 1) - pD->stop_decoding(JPGD_DECODE_ERROR); - - if (pD->get_bits_no_markers(1)) - s = p1; - else - s = m1; - } - else - { - if (r != 15) - { - pD->m_eob_run = 1 << r; - - if (r) - pD->m_eob_run += pD->get_bits_no_markers(r); - - break; - } - } - - do - { - jpgd_block_t *this_coef = p + g_ZAG[k & 63]; - - if (*this_coef != 0) - { - if (pD->get_bits_no_markers(1)) - { - if ((*this_coef & p1) == 0) - { - if (*this_coef >= 0) - *this_coef = static_cast<jpgd_block_t>(*this_coef + p1); - else - *this_coef = static_cast<jpgd_block_t>(*this_coef + m1); - } - } - } - else - { - if (--r < 0) - break; - } - - k++; - - } while (k <= pD->m_spectral_end); - - if ((s) && (k < 64)) - { - p[g_ZAG[k]] = static_cast<jpgd_block_t>(s); - } - } - } - - if (pD->m_eob_run > 0) - { - for ( ; k <= pD->m_spectral_end; k++) - { - jpgd_block_t *this_coef = p + g_ZAG[k & 63]; // logical AND to shut up static code analysis - - if (*this_coef != 0) - { - if (pD->get_bits_no_markers(1)) - { - if ((*this_coef & p1) == 0) - { - if (*this_coef >= 0) - *this_coef = static_cast<jpgd_block_t>(*this_coef + p1); - else - *this_coef = static_cast<jpgd_block_t>(*this_coef + m1); - } - } - } - } - - pD->m_eob_run--; - } -} - -// Decode a scan in a progressively encoded image. -void jpeg_decoder::decode_scan(pDecode_block_func decode_block_func) -{ - int mcu_row, mcu_col, mcu_block; - int block_x_mcu[JPGD_MAX_COMPONENTS], m_block_y_mcu[JPGD_MAX_COMPONENTS]; - - memset(m_block_y_mcu, 0, sizeof(m_block_y_mcu)); - - for (mcu_col = 0; mcu_col < m_mcus_per_col; mcu_col++) - { - int component_num, component_id; - - memset(block_x_mcu, 0, sizeof(block_x_mcu)); - - for (mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) - { - int block_x_mcu_ofs = 0, block_y_mcu_ofs = 0; - - if ((m_restart_interval) && (m_restarts_left == 0)) - process_restart(); - - for (mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) - { - component_id = m_mcu_org[mcu_block]; - - decode_block_func(this, component_id, block_x_mcu[component_id] + block_x_mcu_ofs, m_block_y_mcu[component_id] + block_y_mcu_ofs); - - if (m_comps_in_scan == 1) - block_x_mcu[component_id]++; - else - { - if (++block_x_mcu_ofs == m_comp_h_samp[component_id]) - { - block_x_mcu_ofs = 0; - - if (++block_y_mcu_ofs == m_comp_v_samp[component_id]) - { - block_y_mcu_ofs = 0; - block_x_mcu[component_id] += m_comp_h_samp[component_id]; - } - } - } - } - - m_restarts_left--; - } - - if (m_comps_in_scan == 1) - m_block_y_mcu[m_comp_list[0]]++; - else - { - for (component_num = 0; component_num < m_comps_in_scan; component_num++) - { - component_id = m_comp_list[component_num]; - m_block_y_mcu[component_id] += m_comp_v_samp[component_id]; - } - } - } -} - -// Decode a progressively encoded image. -void jpeg_decoder::init_progressive() -{ - int i; - - if (m_comps_in_frame == 4) - stop_decoding(JPGD_UNSUPPORTED_COLORSPACE); - - // Allocate the coefficient buffers. - for (i = 0; i < m_comps_in_frame; i++) - { - m_dc_coeffs[i] = coeff_buf_open(m_max_mcus_per_row * m_comp_h_samp[i], m_max_mcus_per_col * m_comp_v_samp[i], 1, 1); - m_ac_coeffs[i] = coeff_buf_open(m_max_mcus_per_row * m_comp_h_samp[i], m_max_mcus_per_col * m_comp_v_samp[i], 8, 8); - } - - for ( ; ; ) - { - int dc_only_scan, refinement_scan; - pDecode_block_func decode_block_func; - - if (!init_scan()) - break; - - dc_only_scan = (m_spectral_start == 0); - refinement_scan = (m_successive_high != 0); - - if ((m_spectral_start > m_spectral_end) || (m_spectral_end > 63)) - stop_decoding(JPGD_BAD_SOS_SPECTRAL); - - if (dc_only_scan) - { - if (m_spectral_end) - stop_decoding(JPGD_BAD_SOS_SPECTRAL); - } - else if (m_comps_in_scan != 1) /* AC scans can only contain one component */ - stop_decoding(JPGD_BAD_SOS_SPECTRAL); - - if ((refinement_scan) && (m_successive_low != m_successive_high - 1)) - stop_decoding(JPGD_BAD_SOS_SUCCESSIVE); - - if (dc_only_scan) - { - if (refinement_scan) - decode_block_func = decode_block_dc_refine; - else - decode_block_func = decode_block_dc_first; - } - else - { - if (refinement_scan) - decode_block_func = decode_block_ac_refine; - else - decode_block_func = decode_block_ac_first; - } - - decode_scan(decode_block_func); - - m_bits_left = 16; - get_bits(16); - get_bits(16); - } - - m_comps_in_scan = m_comps_in_frame; - - for (i = 0; i < m_comps_in_frame; i++) - m_comp_list[i] = i; - - calc_mcu_block_order(); -} - -void jpeg_decoder::init_sequential() -{ - if (!init_scan()) - stop_decoding(JPGD_UNEXPECTED_MARKER); -} - -void jpeg_decoder::decode_start() -{ - init_frame(); - - if (m_progressive_flag) - init_progressive(); - else - init_sequential(); -} - -void jpeg_decoder::decode_init(jpeg_decoder_stream *pStream) -{ - init(pStream); - locate_sof_marker(); -} - -jpeg_decoder::jpeg_decoder(jpeg_decoder_stream *pStream) -{ - if (setjmp(m_jmp_state)) - return; - decode_init(pStream); -} - -int jpeg_decoder::begin_decoding() -{ - if (m_ready_flag) - return JPGD_SUCCESS; - - if (m_error_code) - return JPGD_FAILED; - - if (setjmp(m_jmp_state)) - return JPGD_FAILED; - - decode_start(); - - m_ready_flag = true; - - return JPGD_SUCCESS; -} - -jpeg_decoder::~jpeg_decoder() -{ - free_all_blocks(); -} - -jpeg_decoder_file_stream::jpeg_decoder_file_stream() -{ - m_pFile = NULL; - m_eof_flag = false; - m_error_flag = false; -} - -void jpeg_decoder_file_stream::close() -{ - if (m_pFile) - { - fclose(m_pFile); - m_pFile = NULL; - } - - m_eof_flag = false; - m_error_flag = false; -} - -jpeg_decoder_file_stream::~jpeg_decoder_file_stream() -{ - close(); -} - -bool jpeg_decoder_file_stream::open(const char *Pfilename) -{ - close(); - - m_eof_flag = false; - m_error_flag = false; + y += 64 * 6 - 64 * 2; + c += 64 * 6 - 8; + } + } + + uint32_t jpeg_decoder::H2V2ConvertFiltered() + { + const uint BLOCKS_PER_MCU = 6; + int y = m_image_y_size - m_total_lines_left; + int row = y & 15; + + const int half_image_y_size = (m_image_y_size >> 1) - 1; + + uint8* d0 = m_pScan_line_0; + + int c_y0 = (y - 1) >> 1; + int c_y1 = JPGD_MIN(c_y0 + 1, half_image_y_size); + + const uint8_t* p_YSamples = m_pSample_buf; + const uint8_t* p_C0Samples = m_pSample_buf; + if ((c_y0 >= 0) && (((row & 15) == 0) || ((row & 15) == 15)) && (m_total_lines_left > 1)) + { + assert(y > 0); + assert(m_sample_buf_prev_valid); + + if ((row & 15) == 15) + p_YSamples = m_pSample_buf_prev; + + p_C0Samples = m_pSample_buf_prev; + } + + const int y_sample_base_ofs = ((row & 8) ? 128 : 0) + (row & 7) * 8; + const int y0_base = (c_y0 & 7) * 8 + 256; + const int y1_base = (c_y1 & 7) * 8 + 256; + + const int half_image_x_size = (m_image_x_size >> 1) - 1; + + static const uint8_t s_muls[2][2][4] = + { + { { 1, 3, 3, 9 }, { 3, 9, 1, 3 }, }, + { { 3, 1, 9, 3 }, { 9, 3, 3, 1 } } + }; + + if (((row & 15) >= 1) && ((row & 15) <= 14)) + { + assert((row & 1) == 1); + assert(((y + 1 - 1) >> 1) == c_y0); + + assert(p_YSamples == m_pSample_buf); + assert(p_C0Samples == m_pSample_buf); + + uint8* d1 = m_pScan_line_1; + const int y_sample_base_ofs1 = (((row + 1) & 8) ? 128 : 0) + ((row + 1) & 7) * 8; + + for (int x = 0; x < m_image_x_size; x++) + { + int k = (x >> 4) * BLOCKS_PER_MCU * 64 + ((x & 8) ? 64 : 0) + (x & 7); + int y_sample0 = p_YSamples[check_sample_buf_ofs(k + y_sample_base_ofs)]; + int y_sample1 = p_YSamples[check_sample_buf_ofs(k + y_sample_base_ofs1)]; + + int c_x0 = (x - 1) >> 1; + int c_x1 = JPGD_MIN(c_x0 + 1, half_image_x_size); + c_x0 = JPGD_MAX(c_x0, 0); + + int a = (c_x0 >> 3) * BLOCKS_PER_MCU * 64 + (c_x0 & 7); + int cb00_sample = p_C0Samples[check_sample_buf_ofs(a + y0_base)]; + int cr00_sample = p_C0Samples[check_sample_buf_ofs(a + y0_base + 64)]; + + int cb01_sample = m_pSample_buf[check_sample_buf_ofs(a + y1_base)]; + int cr01_sample = m_pSample_buf[check_sample_buf_ofs(a + y1_base + 64)]; + + int b = (c_x1 >> 3) * BLOCKS_PER_MCU * 64 + (c_x1 & 7); + int cb10_sample = p_C0Samples[check_sample_buf_ofs(b + y0_base)]; + int cr10_sample = p_C0Samples[check_sample_buf_ofs(b + y0_base + 64)]; + + int cb11_sample = m_pSample_buf[check_sample_buf_ofs(b + y1_base)]; + int cr11_sample = m_pSample_buf[check_sample_buf_ofs(b + y1_base + 64)]; + + { + const uint8_t* pMuls = &s_muls[row & 1][x & 1][0]; + int cb = (cb00_sample * pMuls[0] + cb01_sample * pMuls[1] + cb10_sample * pMuls[2] + cb11_sample * pMuls[3] + 8) >> 4; + int cr = (cr00_sample * pMuls[0] + cr01_sample * pMuls[1] + cr10_sample * pMuls[2] + cr11_sample * pMuls[3] + 8) >> 4; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d0[0] = clamp(y_sample0 + rc); + d0[1] = clamp(y_sample0 + gc); + d0[2] = clamp(y_sample0 + bc); + d0[3] = 255; + + d0 += 4; + } + + { + const uint8_t* pMuls = &s_muls[(row + 1) & 1][x & 1][0]; + int cb = (cb00_sample * pMuls[0] + cb01_sample * pMuls[1] + cb10_sample * pMuls[2] + cb11_sample * pMuls[3] + 8) >> 4; + int cr = (cr00_sample * pMuls[0] + cr01_sample * pMuls[1] + cr10_sample * pMuls[2] + cr11_sample * pMuls[3] + 8) >> 4; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d1[0] = clamp(y_sample1 + rc); + d1[1] = clamp(y_sample1 + gc); + d1[2] = clamp(y_sample1 + bc); + d1[3] = 255; + + d1 += 4; + } + + if (((x & 1) == 1) && (x < m_image_x_size - 1)) + { + const int nx = x + 1; + assert(c_x0 == (nx - 1) >> 1); + + k = (nx >> 4) * BLOCKS_PER_MCU * 64 + ((nx & 8) ? 64 : 0) + (nx & 7); + y_sample0 = p_YSamples[check_sample_buf_ofs(k + y_sample_base_ofs)]; + y_sample1 = p_YSamples[check_sample_buf_ofs(k + y_sample_base_ofs1)]; + + { + const uint8_t* pMuls = &s_muls[row & 1][nx & 1][0]; + int cb = (cb00_sample * pMuls[0] + cb01_sample * pMuls[1] + cb10_sample * pMuls[2] + cb11_sample * pMuls[3] + 8) >> 4; + int cr = (cr00_sample * pMuls[0] + cr01_sample * pMuls[1] + cr10_sample * pMuls[2] + cr11_sample * pMuls[3] + 8) >> 4; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d0[0] = clamp(y_sample0 + rc); + d0[1] = clamp(y_sample0 + gc); + d0[2] = clamp(y_sample0 + bc); + d0[3] = 255; + + d0 += 4; + } + + { + const uint8_t* pMuls = &s_muls[(row + 1) & 1][nx & 1][0]; + int cb = (cb00_sample * pMuls[0] + cb01_sample * pMuls[1] + cb10_sample * pMuls[2] + cb11_sample * pMuls[3] + 8) >> 4; + int cr = (cr00_sample * pMuls[0] + cr01_sample * pMuls[1] + cr10_sample * pMuls[2] + cr11_sample * pMuls[3] + 8) >> 4; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d1[0] = clamp(y_sample1 + rc); + d1[1] = clamp(y_sample1 + gc); + d1[2] = clamp(y_sample1 + bc); + d1[3] = 255; + + d1 += 4; + } + + ++x; + } + } + + return 2; + } + else + { + for (int x = 0; x < m_image_x_size; x++) + { + int y_sample = p_YSamples[check_sample_buf_ofs((x >> 4) * BLOCKS_PER_MCU * 64 + ((x & 8) ? 64 : 0) + (x & 7) + y_sample_base_ofs)]; + + int c_x0 = (x - 1) >> 1; + int c_x1 = JPGD_MIN(c_x0 + 1, half_image_x_size); + c_x0 = JPGD_MAX(c_x0, 0); + + int a = (c_x0 >> 3) * BLOCKS_PER_MCU * 64 + (c_x0 & 7); + int cb00_sample = p_C0Samples[check_sample_buf_ofs(a + y0_base)]; + int cr00_sample = p_C0Samples[check_sample_buf_ofs(a + y0_base + 64)]; + + int cb01_sample = m_pSample_buf[check_sample_buf_ofs(a + y1_base)]; + int cr01_sample = m_pSample_buf[check_sample_buf_ofs(a + y1_base + 64)]; + + int b = (c_x1 >> 3) * BLOCKS_PER_MCU * 64 + (c_x1 & 7); + int cb10_sample = p_C0Samples[check_sample_buf_ofs(b + y0_base)]; + int cr10_sample = p_C0Samples[check_sample_buf_ofs(b + y0_base + 64)]; + + int cb11_sample = m_pSample_buf[check_sample_buf_ofs(b + y1_base)]; + int cr11_sample = m_pSample_buf[check_sample_buf_ofs(b + y1_base + 64)]; + + const uint8_t* pMuls = &s_muls[row & 1][x & 1][0]; + int cb = (cb00_sample * pMuls[0] + cb01_sample * pMuls[1] + cb10_sample * pMuls[2] + cb11_sample * pMuls[3] + 8) >> 4; + int cr = (cr00_sample * pMuls[0] + cr01_sample * pMuls[1] + cr10_sample * pMuls[2] + cr11_sample * pMuls[3] + 8) >> 4; + + int rc = m_crr[cr]; + int gc = ((m_crg[cr] + m_cbg[cb]) >> 16); + int bc = m_cbb[cb]; + + d0[0] = clamp(y_sample + rc); + d0[1] = clamp(y_sample + gc); + d0[2] = clamp(y_sample + bc); + d0[3] = 255; + + d0 += 4; + } + + return 1; + } + } + + // Y (1 block per MCU) to 8-bit grayscale + void jpeg_decoder::gray_convert() + { + int row = m_max_mcu_y_size - m_mcu_lines_left; + uint8* d = m_pScan_line_0; + uint8* s = m_pSample_buf + row * 8; + + for (int i = m_max_mcus_per_row; i > 0; i--) + { + *(uint*)d = *(uint*)s; + *(uint*)(&d[4]) = *(uint*)(&s[4]); + + s += 64; + d += 8; + } + } + + // Find end of image (EOI) marker, so we can return to the user the exact size of the input stream. + void jpeg_decoder::find_eoi() + { + if (!m_progressive_flag) + { + // Attempt to read the EOI marker. + //get_bits_no_markers(m_bits_left & 7); + + // Prime the bit buffer + m_bits_left = 16; + get_bits(16); + get_bits(16); + + // The next marker _should_ be EOI + process_markers(); + } + + m_total_bytes_read -= m_in_buf_left; + } + + int jpeg_decoder::decode_next_mcu_row() + { + if (::setjmp(m_jmp_state)) + return JPGD_FAILED; + + const bool chroma_y_filtering = ((m_flags & cFlagBoxChromaFiltering) == 0) && ((m_scan_type == JPGD_YH2V2) || (m_scan_type == JPGD_YH1V2)); + if (chroma_y_filtering) + { + std::swap(m_pSample_buf, m_pSample_buf_prev); + + m_sample_buf_prev_valid = true; + } + + if (m_progressive_flag) + load_next_row(); + else + decode_next_row(); + + // Find the EOI marker if that was the last row. + if (m_total_lines_left <= m_max_mcu_y_size) + find_eoi(); + + m_mcu_lines_left = m_max_mcu_y_size; + return 0; + } + + int jpeg_decoder::decode(const void** pScan_line, uint* pScan_line_len) + { + if ((m_error_code) || (!m_ready_flag)) + return JPGD_FAILED; + + if (m_total_lines_left == 0) + return JPGD_DONE; + + const bool chroma_y_filtering = ((m_flags & cFlagBoxChromaFiltering) == 0) && ((m_scan_type == JPGD_YH2V2) || (m_scan_type == JPGD_YH1V2)); + + bool get_another_mcu_row = false; + bool got_mcu_early = false; + if (chroma_y_filtering) + { + if (m_total_lines_left == m_image_y_size) + get_another_mcu_row = true; + else if ((m_mcu_lines_left == 1) && (m_total_lines_left > 1)) + { + get_another_mcu_row = true; + got_mcu_early = true; + } + } + else + { + get_another_mcu_row = (m_mcu_lines_left == 0); + } + + if (get_another_mcu_row) + { + int status = decode_next_mcu_row(); + if (status != 0) + return status; + } + + switch (m_scan_type) + { + case JPGD_YH2V2: + { + if ((m_flags & cFlagBoxChromaFiltering) == 0) + { + if (m_num_buffered_scanlines == 1) + { + *pScan_line = m_pScan_line_1; + } + else if (m_num_buffered_scanlines == 0) + { + m_num_buffered_scanlines = H2V2ConvertFiltered(); + *pScan_line = m_pScan_line_0; + } + + m_num_buffered_scanlines--; + } + else + { + if ((m_mcu_lines_left & 1) == 0) + { + H2V2Convert(); + *pScan_line = m_pScan_line_0; + } + else + *pScan_line = m_pScan_line_1; + } + + break; + } + case JPGD_YH2V1: + { + if ((m_flags & cFlagBoxChromaFiltering) == 0) + H2V1ConvertFiltered(); + else + H2V1Convert(); + *pScan_line = m_pScan_line_0; + break; + } + case JPGD_YH1V2: + { + if (chroma_y_filtering) + { + H1V2ConvertFiltered(); + *pScan_line = m_pScan_line_0; + } + else + { + if ((m_mcu_lines_left & 1) == 0) + { + H1V2Convert(); + *pScan_line = m_pScan_line_0; + } + else + *pScan_line = m_pScan_line_1; + } + + break; + } + case JPGD_YH1V1: + { + H1V1Convert(); + *pScan_line = m_pScan_line_0; + break; + } + case JPGD_GRAYSCALE: + { + gray_convert(); + *pScan_line = m_pScan_line_0; + + break; + } + } + + *pScan_line_len = m_real_dest_bytes_per_scan_line; + + if (!got_mcu_early) + { + m_mcu_lines_left--; + } + + m_total_lines_left--; + + return JPGD_SUCCESS; + } + + // Creates the tables needed for efficient Huffman decoding. + void jpeg_decoder::make_huff_table(int index, huff_tables* pH) + { + int p, i, l, si; + uint8 huffsize[258]; + uint huffcode[258]; + uint code; + uint subtree; + int code_size; + int lastp; + int nextfreeentry; + int currententry; + + pH->ac_table = m_huff_ac[index] != 0; + + p = 0; + + for (l = 1; l <= 16; l++) + { + for (i = 1; i <= m_huff_num[index][l]; i++) + { + if (p >= 257) + stop_decoding(JPGD_DECODE_ERROR); + huffsize[p++] = static_cast<uint8>(l); + } + } + + assert(p < 258); + huffsize[p] = 0; + + lastp = p; + + code = 0; + si = huffsize[0]; + p = 0; + + while (huffsize[p]) + { + while (huffsize[p] == si) + { + if (p >= 257) + stop_decoding(JPGD_DECODE_ERROR); + huffcode[p++] = code; + code++; + } + + code <<= 1; + si++; + } + + memset(pH->look_up, 0, sizeof(pH->look_up)); + memset(pH->look_up2, 0, sizeof(pH->look_up2)); + memset(pH->tree, 0, sizeof(pH->tree)); + memset(pH->code_size, 0, sizeof(pH->code_size)); + + nextfreeentry = -1; + + p = 0; + + while (p < lastp) + { + i = m_huff_val[index][p]; + + code = huffcode[p]; + code_size = huffsize[p]; + + assert(i < JPGD_HUFF_CODE_SIZE_MAX_LENGTH); + pH->code_size[i] = static_cast<uint8>(code_size); + + if (code_size <= 8) + { + code <<= (8 - code_size); + + for (l = 1 << (8 - code_size); l > 0; l--) + { + if (code >= 256) + stop_decoding(JPGD_DECODE_ERROR); + + pH->look_up[code] = i; + + bool has_extrabits = false; + int extra_bits = 0; + int num_extra_bits = i & 15; + + int bits_to_fetch = code_size; + if (num_extra_bits) + { + int total_codesize = code_size + num_extra_bits; + if (total_codesize <= 8) + { + has_extrabits = true; + extra_bits = ((1 << num_extra_bits) - 1) & (code >> (8 - total_codesize)); + + if (extra_bits > 0x7FFF) + stop_decoding(JPGD_DECODE_ERROR); + + bits_to_fetch += num_extra_bits; + } + } + + if (!has_extrabits) + pH->look_up2[code] = i | (bits_to_fetch << 8); + else + pH->look_up2[code] = i | 0x8000 | (extra_bits << 16) | (bits_to_fetch << 8); + + code++; + } + } + else + { + subtree = (code >> (code_size - 8)) & 0xFF; + + currententry = pH->look_up[subtree]; + + if (currententry == 0) + { + pH->look_up[subtree] = currententry = nextfreeentry; + pH->look_up2[subtree] = currententry = nextfreeentry; + + nextfreeentry -= 2; + } + + code <<= (16 - (code_size - 8)); + + for (l = code_size; l > 9; l--) + { + if ((code & 0x8000) == 0) + currententry--; + + unsigned int idx = -currententry - 1; + + if (idx >= JPGD_HUFF_TREE_MAX_LENGTH) + stop_decoding(JPGD_DECODE_ERROR); + + if (pH->tree[idx] == 0) + { + pH->tree[idx] = nextfreeentry; + + currententry = nextfreeentry; + + nextfreeentry -= 2; + } + else + { + currententry = pH->tree[idx]; + } + + code <<= 1; + } + + if ((code & 0x8000) == 0) + currententry--; + + if ((-currententry - 1) >= JPGD_HUFF_TREE_MAX_LENGTH) + stop_decoding(JPGD_DECODE_ERROR); + + pH->tree[-currententry - 1] = i; + } + + p++; + } + } + + // Verifies the quantization tables needed for this scan are available. + void jpeg_decoder::check_quant_tables() + { + for (int i = 0; i < m_comps_in_scan; i++) + if (m_quant[m_comp_quant[m_comp_list[i]]] == nullptr) + stop_decoding(JPGD_UNDEFINED_QUANT_TABLE); + } + + // Verifies that all the Huffman tables needed for this scan are available. + void jpeg_decoder::check_huff_tables() + { + for (int i = 0; i < m_comps_in_scan; i++) + { + if ((m_spectral_start == 0) && (m_huff_num[m_comp_dc_tab[m_comp_list[i]]] == nullptr)) + stop_decoding(JPGD_UNDEFINED_HUFF_TABLE); + + if ((m_spectral_end > 0) && (m_huff_num[m_comp_ac_tab[m_comp_list[i]]] == nullptr)) + stop_decoding(JPGD_UNDEFINED_HUFF_TABLE); + } + + for (int i = 0; i < JPGD_MAX_HUFF_TABLES; i++) + if (m_huff_num[i]) + { + if (!m_pHuff_tabs[i]) + m_pHuff_tabs[i] = (huff_tables*)alloc(sizeof(huff_tables)); + + make_huff_table(i, m_pHuff_tabs[i]); + } + } + + // Determines the component order inside each MCU. + // Also calcs how many MCU's are on each row, etc. + bool jpeg_decoder::calc_mcu_block_order() + { + int component_num, component_id; + int max_h_samp = 0, max_v_samp = 0; + + for (component_id = 0; component_id < m_comps_in_frame; component_id++) + { + if (m_comp_h_samp[component_id] > max_h_samp) + max_h_samp = m_comp_h_samp[component_id]; + + if (m_comp_v_samp[component_id] > max_v_samp) + max_v_samp = m_comp_v_samp[component_id]; + } + + for (component_id = 0; component_id < m_comps_in_frame; component_id++) + { + m_comp_h_blocks[component_id] = ((((m_image_x_size * m_comp_h_samp[component_id]) + (max_h_samp - 1)) / max_h_samp) + 7) / 8; + m_comp_v_blocks[component_id] = ((((m_image_y_size * m_comp_v_samp[component_id]) + (max_v_samp - 1)) / max_v_samp) + 7) / 8; + } + + if (m_comps_in_scan == 1) + { + m_mcus_per_row = m_comp_h_blocks[m_comp_list[0]]; + m_mcus_per_col = m_comp_v_blocks[m_comp_list[0]]; + } + else + { + m_mcus_per_row = (((m_image_x_size + 7) / 8) + (max_h_samp - 1)) / max_h_samp; + m_mcus_per_col = (((m_image_y_size + 7) / 8) + (max_v_samp - 1)) / max_v_samp; + } + + if (m_comps_in_scan == 1) + { + m_mcu_org[0] = m_comp_list[0]; + + m_blocks_per_mcu = 1; + } + else + { + m_blocks_per_mcu = 0; + + for (component_num = 0; component_num < m_comps_in_scan; component_num++) + { + int num_blocks; + + component_id = m_comp_list[component_num]; + + num_blocks = m_comp_h_samp[component_id] * m_comp_v_samp[component_id]; + + while (num_blocks--) + m_mcu_org[m_blocks_per_mcu++] = component_id; + } + } + + if (m_blocks_per_mcu > m_max_blocks_per_mcu) + return false; + + for (int mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) + { + int comp_id = m_mcu_org[mcu_block]; + if (comp_id >= JPGD_MAX_QUANT_TABLES) + return false; + } + + return true; + } + + // Starts a new scan. + int jpeg_decoder::init_scan() + { + if (!locate_sos_marker()) + return JPGD_FALSE; + + if (!calc_mcu_block_order()) + return JPGD_FALSE; + + check_huff_tables(); + + check_quant_tables(); + + memset(m_last_dc_val, 0, m_comps_in_frame * sizeof(uint)); + + m_eob_run = 0; + + if (m_restart_interval) + { + m_restarts_left = m_restart_interval; + m_next_restart_num = 0; + } + + fix_in_buffer(); + + return JPGD_TRUE; + } + + // Starts a frame. Determines if the number of components or sampling factors + // are supported. + void jpeg_decoder::init_frame() + { + int i; + + if (m_comps_in_frame == 1) + { + if ((m_comp_h_samp[0] != 1) || (m_comp_v_samp[0] != 1)) + stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); + + m_scan_type = JPGD_GRAYSCALE; + m_max_blocks_per_mcu = 1; + m_max_mcu_x_size = 8; + m_max_mcu_y_size = 8; + } + else if (m_comps_in_frame == 3) + { + if (((m_comp_h_samp[1] != 1) || (m_comp_v_samp[1] != 1)) || + ((m_comp_h_samp[2] != 1) || (m_comp_v_samp[2] != 1))) + stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); + + if ((m_comp_h_samp[0] == 1) && (m_comp_v_samp[0] == 1)) + { + m_scan_type = JPGD_YH1V1; + + m_max_blocks_per_mcu = 3; + m_max_mcu_x_size = 8; + m_max_mcu_y_size = 8; + } + else if ((m_comp_h_samp[0] == 2) && (m_comp_v_samp[0] == 1)) + { + m_scan_type = JPGD_YH2V1; + m_max_blocks_per_mcu = 4; + m_max_mcu_x_size = 16; + m_max_mcu_y_size = 8; + } + else if ((m_comp_h_samp[0] == 1) && (m_comp_v_samp[0] == 2)) + { + m_scan_type = JPGD_YH1V2; + m_max_blocks_per_mcu = 4; + m_max_mcu_x_size = 8; + m_max_mcu_y_size = 16; + } + else if ((m_comp_h_samp[0] == 2) && (m_comp_v_samp[0] == 2)) + { + m_scan_type = JPGD_YH2V2; + m_max_blocks_per_mcu = 6; + m_max_mcu_x_size = 16; + m_max_mcu_y_size = 16; + } + else + stop_decoding(JPGD_UNSUPPORTED_SAMP_FACTORS); + } + else + stop_decoding(JPGD_UNSUPPORTED_COLORSPACE); + + m_max_mcus_per_row = (m_image_x_size + (m_max_mcu_x_size - 1)) / m_max_mcu_x_size; + m_max_mcus_per_col = (m_image_y_size + (m_max_mcu_y_size - 1)) / m_max_mcu_y_size; + + // These values are for the *destination* pixels: after conversion. + if (m_scan_type == JPGD_GRAYSCALE) + m_dest_bytes_per_pixel = 1; + else + m_dest_bytes_per_pixel = 4; + + m_dest_bytes_per_scan_line = ((m_image_x_size + 15) & 0xFFF0) * m_dest_bytes_per_pixel; + + m_real_dest_bytes_per_scan_line = (m_image_x_size * m_dest_bytes_per_pixel); + + // Initialize two scan line buffers. + m_pScan_line_0 = (uint8*)alloc_aligned(m_dest_bytes_per_scan_line, true); + if ((m_scan_type == JPGD_YH1V2) || (m_scan_type == JPGD_YH2V2)) + m_pScan_line_1 = (uint8*)alloc_aligned(m_dest_bytes_per_scan_line, true); + + m_max_blocks_per_row = m_max_mcus_per_row * m_max_blocks_per_mcu; + + // Should never happen + if (m_max_blocks_per_row > JPGD_MAX_BLOCKS_PER_ROW) + stop_decoding(JPGD_DECODE_ERROR); + + // Allocate the coefficient buffer, enough for one MCU + m_pMCU_coefficients = (jpgd_block_coeff_t *)alloc_aligned(m_max_blocks_per_mcu * 64 * sizeof(jpgd_block_coeff_t)); + + for (i = 0; i < m_max_blocks_per_mcu; i++) + m_mcu_block_max_zag[i] = 64; + + m_pSample_buf = (uint8*)alloc_aligned(m_max_blocks_per_row * 64); + m_pSample_buf_prev = (uint8*)alloc_aligned(m_max_blocks_per_row * 64); + + m_total_lines_left = m_image_y_size; + + m_mcu_lines_left = 0; + + create_look_ups(); + } + + // The coeff_buf series of methods originally stored the coefficients + // into a "virtual" file which was located in EMS, XMS, or a disk file. A cache + // was used to make this process more efficient. Now, we can store the entire + // thing in RAM. + jpeg_decoder::coeff_buf* jpeg_decoder::coeff_buf_open(int block_num_x, int block_num_y, int block_len_x, int block_len_y) + { + coeff_buf* cb = (coeff_buf*)alloc(sizeof(coeff_buf)); + + cb->block_num_x = block_num_x; + cb->block_num_y = block_num_y; + cb->block_len_x = block_len_x; + cb->block_len_y = block_len_y; + cb->block_size = (block_len_x * block_len_y) * sizeof(jpgd_block_coeff_t); + cb->pData = (uint8*)alloc(cb->block_size * block_num_x * block_num_y, true); + return cb; + } + + inline jpgd_block_coeff_t* jpeg_decoder::coeff_buf_getp(coeff_buf* cb, int block_x, int block_y) + { + if ((block_x >= cb->block_num_x) || (block_y >= cb->block_num_y)) + stop_decoding(JPGD_DECODE_ERROR); + + return (jpgd_block_coeff_t*)(cb->pData + block_x * cb->block_size + block_y * (cb->block_size * cb->block_num_x)); + } + + // The following methods decode the various types of m_blocks encountered + // in progressively encoded images. + void jpeg_decoder::decode_block_dc_first(jpeg_decoder* pD, int component_id, int block_x, int block_y) + { + int s, r; + jpgd_block_coeff_t* p = pD->coeff_buf_getp(pD->m_dc_coeffs[component_id], block_x, block_y); + + if ((s = pD->huff_decode(pD->m_pHuff_tabs[pD->m_comp_dc_tab[component_id]])) != 0) + { + if (s >= 16) + pD->stop_decoding(JPGD_DECODE_ERROR); + + r = pD->get_bits_no_markers(s); + s = JPGD_HUFF_EXTEND(r, s); + } + + pD->m_last_dc_val[component_id] = (s += pD->m_last_dc_val[component_id]); + + p[0] = static_cast<jpgd_block_coeff_t>(s << pD->m_successive_low); + } + + void jpeg_decoder::decode_block_dc_refine(jpeg_decoder* pD, int component_id, int block_x, int block_y) + { + if (pD->get_bits_no_markers(1)) + { + jpgd_block_coeff_t* p = pD->coeff_buf_getp(pD->m_dc_coeffs[component_id], block_x, block_y); + + p[0] |= (1 << pD->m_successive_low); + } + } + + void jpeg_decoder::decode_block_ac_first(jpeg_decoder* pD, int component_id, int block_x, int block_y) + { + int k, s, r; + + if (pD->m_eob_run) + { + pD->m_eob_run--; + return; + } + + jpgd_block_coeff_t* p = pD->coeff_buf_getp(pD->m_ac_coeffs[component_id], block_x, block_y); + + for (k = pD->m_spectral_start; k <= pD->m_spectral_end; k++) + { + unsigned int idx = pD->m_comp_ac_tab[component_id]; + if (idx >= JPGD_MAX_HUFF_TABLES) + pD->stop_decoding(JPGD_DECODE_ERROR); + + s = pD->huff_decode(pD->m_pHuff_tabs[idx]); + + r = s >> 4; + s &= 15; + + if (s) + { + if ((k += r) > 63) + pD->stop_decoding(JPGD_DECODE_ERROR); + + r = pD->get_bits_no_markers(s); + s = JPGD_HUFF_EXTEND(r, s); + + p[g_ZAG[k]] = static_cast<jpgd_block_coeff_t>(s << pD->m_successive_low); + } + else + { + if (r == 15) + { + if ((k += 15) > 63) + pD->stop_decoding(JPGD_DECODE_ERROR); + } + else + { + pD->m_eob_run = 1 << r; + + if (r) + pD->m_eob_run += pD->get_bits_no_markers(r); + + pD->m_eob_run--; + + break; + } + } + } + } + + void jpeg_decoder::decode_block_ac_refine(jpeg_decoder* pD, int component_id, int block_x, int block_y) + { + int s, k, r; + + int p1 = 1 << pD->m_successive_low; + + //int m1 = (-1) << pD->m_successive_low; + int m1 = static_cast<int>((UINT32_MAX << pD->m_successive_low)); + + jpgd_block_coeff_t* p = pD->coeff_buf_getp(pD->m_ac_coeffs[component_id], block_x, block_y); + if (pD->m_spectral_end > 63) + pD->stop_decoding(JPGD_DECODE_ERROR); + + k = pD->m_spectral_start; + + if (pD->m_eob_run == 0) + { + for (; k <= pD->m_spectral_end; k++) + { + unsigned int idx = pD->m_comp_ac_tab[component_id]; + if (idx >= JPGD_MAX_HUFF_TABLES) + pD->stop_decoding(JPGD_DECODE_ERROR); + + s = pD->huff_decode(pD->m_pHuff_tabs[idx]); + + r = s >> 4; + s &= 15; + + if (s) + { + if (s != 1) + pD->stop_decoding(JPGD_DECODE_ERROR); + + if (pD->get_bits_no_markers(1)) + s = p1; + else + s = m1; + } + else + { + if (r != 15) + { + pD->m_eob_run = 1 << r; + + if (r) + pD->m_eob_run += pD->get_bits_no_markers(r); + + break; + } + } + + do + { + jpgd_block_coeff_t* this_coef = p + g_ZAG[k & 63]; + + if (*this_coef != 0) + { + if (pD->get_bits_no_markers(1)) + { + if ((*this_coef & p1) == 0) + { + if (*this_coef >= 0) + *this_coef = static_cast<jpgd_block_coeff_t>(*this_coef + p1); + else + *this_coef = static_cast<jpgd_block_coeff_t>(*this_coef + m1); + } + } + } + else + { + if (--r < 0) + break; + } + + k++; + + } while (k <= pD->m_spectral_end); + + if ((s) && (k < 64)) + { + p[g_ZAG[k]] = static_cast<jpgd_block_coeff_t>(s); + } + } + } + + if (pD->m_eob_run > 0) + { + for (; k <= pD->m_spectral_end; k++) + { + jpgd_block_coeff_t* this_coef = p + g_ZAG[k & 63]; // logical AND to shut up static code analysis + + if (*this_coef != 0) + { + if (pD->get_bits_no_markers(1)) + { + if ((*this_coef & p1) == 0) + { + if (*this_coef >= 0) + *this_coef = static_cast<jpgd_block_coeff_t>(*this_coef + p1); + else + *this_coef = static_cast<jpgd_block_coeff_t>(*this_coef + m1); + } + } + } + } + + pD->m_eob_run--; + } + } + + // Decode a scan in a progressively encoded image. + void jpeg_decoder::decode_scan(pDecode_block_func decode_block_func) + { + int mcu_row, mcu_col, mcu_block; + int block_x_mcu[JPGD_MAX_COMPONENTS], block_y_mcu[JPGD_MAX_COMPONENTS]; + + memset(block_y_mcu, 0, sizeof(block_y_mcu)); + + for (mcu_col = 0; mcu_col < m_mcus_per_col; mcu_col++) + { + int component_num, component_id; + + memset(block_x_mcu, 0, sizeof(block_x_mcu)); + + for (mcu_row = 0; mcu_row < m_mcus_per_row; mcu_row++) + { + int block_x_mcu_ofs = 0, block_y_mcu_ofs = 0; + + if ((m_restart_interval) && (m_restarts_left == 0)) + process_restart(); + + for (mcu_block = 0; mcu_block < m_blocks_per_mcu; mcu_block++) + { + component_id = m_mcu_org[mcu_block]; + + decode_block_func(this, component_id, block_x_mcu[component_id] + block_x_mcu_ofs, block_y_mcu[component_id] + block_y_mcu_ofs); + + if (m_comps_in_scan == 1) + block_x_mcu[component_id]++; + else + { + if (++block_x_mcu_ofs == m_comp_h_samp[component_id]) + { + block_x_mcu_ofs = 0; + + if (++block_y_mcu_ofs == m_comp_v_samp[component_id]) + { + block_y_mcu_ofs = 0; + block_x_mcu[component_id] += m_comp_h_samp[component_id]; + } + } + } + } + + m_restarts_left--; + } + + if (m_comps_in_scan == 1) + block_y_mcu[m_comp_list[0]]++; + else + { + for (component_num = 0; component_num < m_comps_in_scan; component_num++) + { + component_id = m_comp_list[component_num]; + block_y_mcu[component_id] += m_comp_v_samp[component_id]; + } + } + } + } + + // Decode a progressively encoded image. + void jpeg_decoder::init_progressive() + { + int i; + + if (m_comps_in_frame == 4) + stop_decoding(JPGD_UNSUPPORTED_COLORSPACE); + + // Allocate the coefficient buffers. + for (i = 0; i < m_comps_in_frame; i++) + { + m_dc_coeffs[i] = coeff_buf_open(m_max_mcus_per_row * m_comp_h_samp[i], m_max_mcus_per_col * m_comp_v_samp[i], 1, 1); + m_ac_coeffs[i] = coeff_buf_open(m_max_mcus_per_row * m_comp_h_samp[i], m_max_mcus_per_col * m_comp_v_samp[i], 8, 8); + } + + // See https://libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf + uint32_t total_scans = 0; + const uint32_t MAX_SCANS_TO_PROCESS = 1000; + + for (; ; ) + { + int dc_only_scan, refinement_scan; + pDecode_block_func decode_block_func; + + if (!init_scan()) + break; + + dc_only_scan = (m_spectral_start == 0); + refinement_scan = (m_successive_high != 0); + + if ((m_spectral_start > m_spectral_end) || (m_spectral_end > 63)) + stop_decoding(JPGD_BAD_SOS_SPECTRAL); + + if (dc_only_scan) + { + if (m_spectral_end) + stop_decoding(JPGD_BAD_SOS_SPECTRAL); + } + else if (m_comps_in_scan != 1) /* AC scans can only contain one component */ + stop_decoding(JPGD_BAD_SOS_SPECTRAL); + + if ((refinement_scan) && (m_successive_low != m_successive_high - 1)) + stop_decoding(JPGD_BAD_SOS_SUCCESSIVE); + + if (dc_only_scan) + { + if (refinement_scan) + decode_block_func = decode_block_dc_refine; + else + decode_block_func = decode_block_dc_first; + } + else + { + if (refinement_scan) + decode_block_func = decode_block_ac_refine; + else + decode_block_func = decode_block_ac_first; + } + + decode_scan(decode_block_func); + + m_bits_left = 16; + get_bits(16); + get_bits(16); + + total_scans++; + if (total_scans > MAX_SCANS_TO_PROCESS) + stop_decoding(JPGD_TOO_MANY_SCANS); + } + + m_comps_in_scan = m_comps_in_frame; + + for (i = 0; i < m_comps_in_frame; i++) + m_comp_list[i] = i; + + if (!calc_mcu_block_order()) + stop_decoding(JPGD_DECODE_ERROR); + } + + void jpeg_decoder::init_sequential() + { + if (!init_scan()) + stop_decoding(JPGD_UNEXPECTED_MARKER); + } + + void jpeg_decoder::decode_start() + { + init_frame(); + + if (m_progressive_flag) + init_progressive(); + else + init_sequential(); + } + + void jpeg_decoder::decode_init(jpeg_decoder_stream* pStream, uint32_t flags) + { + init(pStream, flags); + locate_sof_marker(); + } + + jpeg_decoder::jpeg_decoder(jpeg_decoder_stream* pStream, uint32_t flags) + { + if (::setjmp(m_jmp_state)) + return; + decode_init(pStream, flags); + } + + int jpeg_decoder::begin_decoding() + { + if (m_ready_flag) + return JPGD_SUCCESS; + + if (m_error_code) + return JPGD_FAILED; + + if (::setjmp(m_jmp_state)) + return JPGD_FAILED; + + decode_start(); + + m_ready_flag = true; + + return JPGD_SUCCESS; + } + + jpeg_decoder::~jpeg_decoder() + { + free_all_blocks(); + } + + jpeg_decoder_file_stream::jpeg_decoder_file_stream() + { + m_pFile = nullptr; + m_eof_flag = false; + m_error_flag = false; + } + + void jpeg_decoder_file_stream::close() + { + if (m_pFile) + { + fclose(m_pFile); + m_pFile = nullptr; + } + + m_eof_flag = false; + m_error_flag = false; + } + + jpeg_decoder_file_stream::~jpeg_decoder_file_stream() + { + close(); + } + + bool jpeg_decoder_file_stream::open(const char* Pfilename) + { + close(); + + m_eof_flag = false; + m_error_flag = false; #if defined(_MSC_VER) - m_pFile = NULL; - fopen_s(&m_pFile, Pfilename, "rb"); + m_pFile = nullptr; + fopen_s(&m_pFile, Pfilename, "rb"); #else - m_pFile = fopen(Pfilename, "rb"); + m_pFile = fopen(Pfilename, "rb"); #endif - return m_pFile != NULL; -} - -int jpeg_decoder_file_stream::read(uint8 *pBuf, int max_bytes_to_read, bool *pEOF_flag) -{ - if (!m_pFile) - return -1; - - if (m_eof_flag) - { - *pEOF_flag = true; - return 0; - } - - if (m_error_flag) - return -1; - - int bytes_read = static_cast<int>(fread(pBuf, 1, max_bytes_to_read, m_pFile)); - if (bytes_read < max_bytes_to_read) - { - if (ferror(m_pFile)) - { - m_error_flag = true; - return -1; - } - - m_eof_flag = true; - *pEOF_flag = true; - } - - return bytes_read; -} - -bool jpeg_decoder_mem_stream::open(const uint8 *pSrc_data, uint size) -{ - close(); - m_pSrc_data = pSrc_data; - m_ofs = 0; - m_size = size; - return true; -} - -int jpeg_decoder_mem_stream::read(uint8 *pBuf, int max_bytes_to_read, bool *pEOF_flag) -{ - *pEOF_flag = false; - - if (!m_pSrc_data) - return -1; - - uint bytes_remaining = m_size - m_ofs; - if ((uint)max_bytes_to_read > bytes_remaining) - { - max_bytes_to_read = bytes_remaining; - *pEOF_flag = true; - } - - memcpy(pBuf, m_pSrc_data + m_ofs, max_bytes_to_read); - m_ofs += max_bytes_to_read; - - return max_bytes_to_read; -} - -unsigned char *decompress_jpeg_image_from_stream(jpeg_decoder_stream *pStream, int *width, int *height, int *actual_comps, int req_comps) -{ - if (!actual_comps) - return NULL; - *actual_comps = 0; - - if ((!pStream) || (!width) || (!height) || (!req_comps)) - return NULL; - - if ((req_comps != 1) && (req_comps != 3) && (req_comps != 4)) - return NULL; - - jpeg_decoder decoder(pStream); - if (decoder.get_error_code() != JPGD_SUCCESS) - return NULL; - - const int image_width = decoder.get_width(), image_height = decoder.get_height(); - *width = image_width; - *height = image_height; - *actual_comps = decoder.get_num_components(); - - if (decoder.begin_decoding() != JPGD_SUCCESS) - return NULL; - - const int dst_bpl = image_width * req_comps; - - uint8 *pImage_data = (uint8*)jpgd_malloc(dst_bpl * image_height); - if (!pImage_data) - return NULL; - - for (int y = 0; y < image_height; y++) - { - const uint8* pScan_line; - uint scan_line_len; - if (decoder.decode((const void**)&pScan_line, &scan_line_len) != JPGD_SUCCESS) - { - jpgd_free(pImage_data); - return NULL; - } - - uint8 *pDst = pImage_data + y * dst_bpl; - - if (((req_comps == 1) && (decoder.get_num_components() == 1)) || ((req_comps == 4) && (decoder.get_num_components() == 3))) - memcpy(pDst, pScan_line, dst_bpl); - else if (decoder.get_num_components() == 1) - { - if (req_comps == 3) - { - for (int x = 0; x < image_width; x++) - { - uint8 luma = pScan_line[x]; - pDst[0] = luma; - pDst[1] = luma; - pDst[2] = luma; - pDst += 3; - } - } - else - { - for (int x = 0; x < image_width; x++) - { - uint8 luma = pScan_line[x]; - pDst[0] = luma; - pDst[1] = luma; - pDst[2] = luma; - pDst[3] = 255; - pDst += 4; - } - } - } - else if (decoder.get_num_components() == 3) - { - if (req_comps == 1) - { - const int YR = 19595, YG = 38470, YB = 7471; - for (int x = 0; x < image_width; x++) - { - int r = pScan_line[x*4+0]; - int g = pScan_line[x*4+1]; - int b = pScan_line[x*4+2]; - *pDst++ = static_cast<uint8>((r * YR + g * YG + b * YB + 32768) >> 16); - } - } - else - { - for (int x = 0; x < image_width; x++) - { - pDst[0] = pScan_line[x*4+0]; - pDst[1] = pScan_line[x*4+1]; - pDst[2] = pScan_line[x*4+2]; - pDst += 3; - } - } - } - } - - return pImage_data; -} - -unsigned char *decompress_jpeg_image_from_memory(const unsigned char *pSrc_data, int src_data_size, int *width, int *height, int *actual_comps, int req_comps) -{ - jpgd::jpeg_decoder_mem_stream mem_stream(pSrc_data, src_data_size); - return decompress_jpeg_image_from_stream(&mem_stream, width, height, actual_comps, req_comps); -} - -unsigned char *decompress_jpeg_image_from_file(const char *pSrc_filename, int *width, int *height, int *actual_comps, int req_comps) -{ - jpgd::jpeg_decoder_file_stream file_stream; - if (!file_stream.open(pSrc_filename)) - return NULL; - return decompress_jpeg_image_from_stream(&file_stream, width, height, actual_comps, req_comps); -} - -} // namespace jpgd
\ No newline at end of file + return m_pFile != nullptr; + } + + int jpeg_decoder_file_stream::read(uint8* pBuf, int max_bytes_to_read, bool* pEOF_flag) + { + if (!m_pFile) + return -1; + + if (m_eof_flag) + { + *pEOF_flag = true; + return 0; + } + + if (m_error_flag) + return -1; + + int bytes_read = static_cast<int>(fread(pBuf, 1, max_bytes_to_read, m_pFile)); + if (bytes_read < max_bytes_to_read) + { + if (ferror(m_pFile)) + { + m_error_flag = true; + return -1; + } + + m_eof_flag = true; + *pEOF_flag = true; + } + + return bytes_read; + } + + bool jpeg_decoder_mem_stream::open(const uint8* pSrc_data, uint size) + { + close(); + m_pSrc_data = pSrc_data; + m_ofs = 0; + m_size = size; + return true; + } + + int jpeg_decoder_mem_stream::read(uint8* pBuf, int max_bytes_to_read, bool* pEOF_flag) + { + *pEOF_flag = false; + + if (!m_pSrc_data) + return -1; + + uint bytes_remaining = m_size - m_ofs; + if ((uint)max_bytes_to_read > bytes_remaining) + { + max_bytes_to_read = bytes_remaining; + *pEOF_flag = true; + } + + memcpy(pBuf, m_pSrc_data + m_ofs, max_bytes_to_read); + m_ofs += max_bytes_to_read; + + return max_bytes_to_read; + } + + unsigned char* decompress_jpeg_image_from_stream(jpeg_decoder_stream* pStream, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags) + { + if (!actual_comps) + return nullptr; + *actual_comps = 0; + + if ((!pStream) || (!width) || (!height) || (!req_comps)) + return nullptr; + + if ((req_comps != 1) && (req_comps != 3) && (req_comps != 4)) + return nullptr; + + jpeg_decoder decoder(pStream, flags); + if (decoder.get_error_code() != JPGD_SUCCESS) + return nullptr; + + const int image_width = decoder.get_width(), image_height = decoder.get_height(); + *width = image_width; + *height = image_height; + *actual_comps = decoder.get_num_components(); + + if (decoder.begin_decoding() != JPGD_SUCCESS) + return nullptr; + + const int dst_bpl = image_width * req_comps; + + uint8* pImage_data = (uint8*)jpgd_malloc(dst_bpl * image_height); + if (!pImage_data) + return nullptr; + + for (int y = 0; y < image_height; y++) + { + const uint8* pScan_line; + uint scan_line_len; + if (decoder.decode((const void**)&pScan_line, &scan_line_len) != JPGD_SUCCESS) + { + jpgd_free(pImage_data); + return nullptr; + } + + uint8* pDst = pImage_data + y * dst_bpl; + + if (((req_comps == 1) && (decoder.get_num_components() == 1)) || ((req_comps == 4) && (decoder.get_num_components() == 3))) + memcpy(pDst, pScan_line, dst_bpl); + else if (decoder.get_num_components() == 1) + { + if (req_comps == 3) + { + for (int x = 0; x < image_width; x++) + { + uint8 luma = pScan_line[x]; + pDst[0] = luma; + pDst[1] = luma; + pDst[2] = luma; + pDst += 3; + } + } + else + { + for (int x = 0; x < image_width; x++) + { + uint8 luma = pScan_line[x]; + pDst[0] = luma; + pDst[1] = luma; + pDst[2] = luma; + pDst[3] = 255; + pDst += 4; + } + } + } + else if (decoder.get_num_components() == 3) + { + if (req_comps == 1) + { + const int YR = 19595, YG = 38470, YB = 7471; + for (int x = 0; x < image_width; x++) + { + int r = pScan_line[x * 4 + 0]; + int g = pScan_line[x * 4 + 1]; + int b = pScan_line[x * 4 + 2]; + *pDst++ = static_cast<uint8>((r * YR + g * YG + b * YB + 32768) >> 16); + } + } + else + { + for (int x = 0; x < image_width; x++) + { + pDst[0] = pScan_line[x * 4 + 0]; + pDst[1] = pScan_line[x * 4 + 1]; + pDst[2] = pScan_line[x * 4 + 2]; + pDst += 3; + } + } + } + } + + return pImage_data; + } + + unsigned char* decompress_jpeg_image_from_memory(const unsigned char* pSrc_data, int src_data_size, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags) + { + jpgd::jpeg_decoder_mem_stream mem_stream(pSrc_data, src_data_size); + return decompress_jpeg_image_from_stream(&mem_stream, width, height, actual_comps, req_comps, flags); + } + + unsigned char* decompress_jpeg_image_from_file(const char* pSrc_filename, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags) + { + jpgd::jpeg_decoder_file_stream file_stream; + if (!file_stream.open(pSrc_filename)) + return nullptr; + return decompress_jpeg_image_from_stream(&file_stream, width, height, actual_comps, req_comps, flags); + } + +} // namespace jpgd |