diff options
Diffstat (limited to 'drivers/webp/dec/vp8l.c')
| -rw-r--r-- | drivers/webp/dec/vp8l.c | 1660 |
1 files changed, 0 insertions, 1660 deletions
diff --git a/drivers/webp/dec/vp8l.c b/drivers/webp/dec/vp8l.c deleted file mode 100644 index cb2e3176b6..0000000000 --- a/drivers/webp/dec/vp8l.c +++ /dev/null @@ -1,1660 +0,0 @@ -// Copyright 2012 Google Inc. All Rights Reserved. -// -// Use of this source code is governed by a BSD-style license -// that can be found in the COPYING file in the root of the source -// tree. An additional intellectual property rights grant can be found -// in the file PATENTS. All contributing project authors may -// be found in the AUTHORS file in the root of the source tree. -// ----------------------------------------------------------------------------- -// -// main entry for the decoder -// -// Authors: Vikas Arora (vikaas.arora@gmail.com) -// Jyrki Alakuijala (jyrki@google.com) - -#include <stdlib.h> - -#include "./alphai.h" -#include "./vp8li.h" -#include "../dsp/dsp.h" -#include "../dsp/lossless.h" -#include "../dsp/yuv.h" -#include "../utils/endian_inl.h" -#include "../utils/huffman.h" -#include "../utils/utils.h" - -#define NUM_ARGB_CACHE_ROWS 16 - -static const int kCodeLengthLiterals = 16; -static const int kCodeLengthRepeatCode = 16; -static const int kCodeLengthExtraBits[3] = { 2, 3, 7 }; -static const int kCodeLengthRepeatOffsets[3] = { 3, 3, 11 }; - -// ----------------------------------------------------------------------------- -// Five Huffman codes are used at each meta code: -// 1. green + length prefix codes + color cache codes, -// 2. alpha, -// 3. red, -// 4. blue, and, -// 5. distance prefix codes. -typedef enum { - GREEN = 0, - RED = 1, - BLUE = 2, - ALPHA = 3, - DIST = 4 -} HuffIndex; - -static const uint16_t kAlphabetSize[HUFFMAN_CODES_PER_META_CODE] = { - NUM_LITERAL_CODES + NUM_LENGTH_CODES, - NUM_LITERAL_CODES, NUM_LITERAL_CODES, NUM_LITERAL_CODES, - NUM_DISTANCE_CODES -}; - -static const uint8_t kLiteralMap[HUFFMAN_CODES_PER_META_CODE] = { - 0, 1, 1, 1, 0 -}; - -#define NUM_CODE_LENGTH_CODES 19 -static const uint8_t kCodeLengthCodeOrder[NUM_CODE_LENGTH_CODES] = { - 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 -}; - -#define CODE_TO_PLANE_CODES 120 -static const uint8_t kCodeToPlane[CODE_TO_PLANE_CODES] = { - 0x18, 0x07, 0x17, 0x19, 0x28, 0x06, 0x27, 0x29, 0x16, 0x1a, - 0x26, 0x2a, 0x38, 0x05, 0x37, 0x39, 0x15, 0x1b, 0x36, 0x3a, - 0x25, 0x2b, 0x48, 0x04, 0x47, 0x49, 0x14, 0x1c, 0x35, 0x3b, - 0x46, 0x4a, 0x24, 0x2c, 0x58, 0x45, 0x4b, 0x34, 0x3c, 0x03, - 0x57, 0x59, 0x13, 0x1d, 0x56, 0x5a, 0x23, 0x2d, 0x44, 0x4c, - 0x55, 0x5b, 0x33, 0x3d, 0x68, 0x02, 0x67, 0x69, 0x12, 0x1e, - 0x66, 0x6a, 0x22, 0x2e, 0x54, 0x5c, 0x43, 0x4d, 0x65, 0x6b, - 0x32, 0x3e, 0x78, 0x01, 0x77, 0x79, 0x53, 0x5d, 0x11, 0x1f, - 0x64, 0x6c, 0x42, 0x4e, 0x76, 0x7a, 0x21, 0x2f, 0x75, 0x7b, - 0x31, 0x3f, 0x63, 0x6d, 0x52, 0x5e, 0x00, 0x74, 0x7c, 0x41, - 0x4f, 0x10, 0x20, 0x62, 0x6e, 0x30, 0x73, 0x7d, 0x51, 0x5f, - 0x40, 0x72, 0x7e, 0x61, 0x6f, 0x50, 0x71, 0x7f, 0x60, 0x70 -}; - -// Memory needed for lookup tables of one Huffman tree group. Red, blue, alpha -// and distance alphabets are constant (256 for red, blue and alpha, 40 for -// distance) and lookup table sizes for them in worst case are 630 and 410 -// respectively. Size of green alphabet depends on color cache size and is equal -// to 256 (green component values) + 24 (length prefix values) -// + color_cache_size (between 0 and 2048). -// All values computed for 8-bit first level lookup with Mark Adler's tool: -// http://www.hdfgroup.org/ftp/lib-external/zlib/zlib-1.2.5/examples/enough.c -#define FIXED_TABLE_SIZE (630 * 3 + 410) -static const int kTableSize[12] = { - FIXED_TABLE_SIZE + 654, - FIXED_TABLE_SIZE + 656, - FIXED_TABLE_SIZE + 658, - FIXED_TABLE_SIZE + 662, - FIXED_TABLE_SIZE + 670, - FIXED_TABLE_SIZE + 686, - FIXED_TABLE_SIZE + 718, - FIXED_TABLE_SIZE + 782, - FIXED_TABLE_SIZE + 912, - FIXED_TABLE_SIZE + 1168, - FIXED_TABLE_SIZE + 1680, - FIXED_TABLE_SIZE + 2704 -}; - -static int DecodeImageStream(int xsize, int ysize, - int is_level0, - VP8LDecoder* const dec, - uint32_t** const decoded_data); - -//------------------------------------------------------------------------------ - -int VP8LCheckSignature(const uint8_t* const data, size_t size) { - return (size >= VP8L_FRAME_HEADER_SIZE && - data[0] == VP8L_MAGIC_BYTE && - (data[4] >> 5) == 0); // version -} - -static int ReadImageInfo(VP8LBitReader* const br, - int* const width, int* const height, - int* const has_alpha) { - if (VP8LReadBits(br, 8) != VP8L_MAGIC_BYTE) return 0; - *width = VP8LReadBits(br, VP8L_IMAGE_SIZE_BITS) + 1; - *height = VP8LReadBits(br, VP8L_IMAGE_SIZE_BITS) + 1; - *has_alpha = VP8LReadBits(br, 1); - if (VP8LReadBits(br, VP8L_VERSION_BITS) != 0) return 0; - return !br->eos_; -} - -int VP8LGetInfo(const uint8_t* data, size_t data_size, - int* const width, int* const height, int* const has_alpha) { - if (data == NULL || data_size < VP8L_FRAME_HEADER_SIZE) { - return 0; // not enough data - } else if (!VP8LCheckSignature(data, data_size)) { - return 0; // bad signature - } else { - int w, h, a; - VP8LBitReader br; - VP8LInitBitReader(&br, data, data_size); - if (!ReadImageInfo(&br, &w, &h, &a)) { - return 0; - } - if (width != NULL) *width = w; - if (height != NULL) *height = h; - if (has_alpha != NULL) *has_alpha = a; - return 1; - } -} - -//------------------------------------------------------------------------------ - -static WEBP_INLINE int GetCopyDistance(int distance_symbol, - VP8LBitReader* const br) { - int extra_bits, offset; - if (distance_symbol < 4) { - return distance_symbol + 1; - } - extra_bits = (distance_symbol - 2) >> 1; - offset = (2 + (distance_symbol & 1)) << extra_bits; - return offset + VP8LReadBits(br, extra_bits) + 1; -} - -static WEBP_INLINE int GetCopyLength(int length_symbol, - VP8LBitReader* const br) { - // Length and distance prefixes are encoded the same way. - return GetCopyDistance(length_symbol, br); -} - -static WEBP_INLINE int PlaneCodeToDistance(int xsize, int plane_code) { - if (plane_code > CODE_TO_PLANE_CODES) { - return plane_code - CODE_TO_PLANE_CODES; - } else { - const int dist_code = kCodeToPlane[plane_code - 1]; - const int yoffset = dist_code >> 4; - const int xoffset = 8 - (dist_code & 0xf); - const int dist = yoffset * xsize + xoffset; - return (dist >= 1) ? dist : 1; // dist<1 can happen if xsize is very small - } -} - -//------------------------------------------------------------------------------ -// Decodes the next Huffman code from bit-stream. -// FillBitWindow(br) needs to be called at minimum every second call -// to ReadSymbol, in order to pre-fetch enough bits. -static WEBP_INLINE int ReadSymbol(const HuffmanCode* table, - VP8LBitReader* const br) { - int nbits; - uint32_t val = VP8LPrefetchBits(br); - table += val & HUFFMAN_TABLE_MASK; - nbits = table->bits - HUFFMAN_TABLE_BITS; - if (nbits > 0) { - VP8LSetBitPos(br, br->bit_pos_ + HUFFMAN_TABLE_BITS); - val = VP8LPrefetchBits(br); - table += table->value; - table += val & ((1 << nbits) - 1); - } - VP8LSetBitPos(br, br->bit_pos_ + table->bits); - return table->value; -} - -// Reads packed symbol depending on GREEN channel -#define BITS_SPECIAL_MARKER 0x100 // something large enough (and a bit-mask) -#define PACKED_NON_LITERAL_CODE 0 // must be < NUM_LITERAL_CODES -static WEBP_INLINE int ReadPackedSymbols(const HTreeGroup* group, - VP8LBitReader* const br, - uint32_t* const dst) { - const uint32_t val = VP8LPrefetchBits(br) & (HUFFMAN_PACKED_TABLE_SIZE - 1); - const HuffmanCode32 code = group->packed_table[val]; - assert(group->use_packed_table); - if (code.bits < BITS_SPECIAL_MARKER) { - VP8LSetBitPos(br, br->bit_pos_ + code.bits); - *dst = code.value; - return PACKED_NON_LITERAL_CODE; - } else { - VP8LSetBitPos(br, br->bit_pos_ + code.bits - BITS_SPECIAL_MARKER); - assert(code.value >= NUM_LITERAL_CODES); - return code.value; - } -} - -static int AccumulateHCode(HuffmanCode hcode, int shift, - HuffmanCode32* const huff) { - huff->bits += hcode.bits; - huff->value |= (uint32_t)hcode.value << shift; - assert(huff->bits <= HUFFMAN_TABLE_BITS); - return hcode.bits; -} - -static void BuildPackedTable(HTreeGroup* const htree_group) { - uint32_t code; - for (code = 0; code < HUFFMAN_PACKED_TABLE_SIZE; ++code) { - uint32_t bits = code; - HuffmanCode32* const huff = &htree_group->packed_table[bits]; - HuffmanCode hcode = htree_group->htrees[GREEN][bits]; - if (hcode.value >= NUM_LITERAL_CODES) { - huff->bits = hcode.bits + BITS_SPECIAL_MARKER; - huff->value = hcode.value; - } else { - huff->bits = 0; - huff->value = 0; - bits >>= AccumulateHCode(hcode, 8, huff); - bits >>= AccumulateHCode(htree_group->htrees[RED][bits], 16, huff); - bits >>= AccumulateHCode(htree_group->htrees[BLUE][bits], 0, huff); - bits >>= AccumulateHCode(htree_group->htrees[ALPHA][bits], 24, huff); - (void)bits; - } - } -} - -static int ReadHuffmanCodeLengths( - VP8LDecoder* const dec, const int* const code_length_code_lengths, - int num_symbols, int* const code_lengths) { - int ok = 0; - VP8LBitReader* const br = &dec->br_; - int symbol; - int max_symbol; - int prev_code_len = DEFAULT_CODE_LENGTH; - HuffmanCode table[1 << LENGTHS_TABLE_BITS]; - - if (!VP8LBuildHuffmanTable(table, LENGTHS_TABLE_BITS, - code_length_code_lengths, - NUM_CODE_LENGTH_CODES)) { - goto End; - } - - if (VP8LReadBits(br, 1)) { // use length - const int length_nbits = 2 + 2 * VP8LReadBits(br, 3); - max_symbol = 2 + VP8LReadBits(br, length_nbits); - if (max_symbol > num_symbols) { - goto End; - } - } else { - max_symbol = num_symbols; - } - - symbol = 0; - while (symbol < num_symbols) { - const HuffmanCode* p; - int code_len; - if (max_symbol-- == 0) break; - VP8LFillBitWindow(br); - p = &table[VP8LPrefetchBits(br) & LENGTHS_TABLE_MASK]; - VP8LSetBitPos(br, br->bit_pos_ + p->bits); - code_len = p->value; - if (code_len < kCodeLengthLiterals) { - code_lengths[symbol++] = code_len; - if (code_len != 0) prev_code_len = code_len; - } else { - const int use_prev = (code_len == kCodeLengthRepeatCode); - const int slot = code_len - kCodeLengthLiterals; - const int extra_bits = kCodeLengthExtraBits[slot]; - const int repeat_offset = kCodeLengthRepeatOffsets[slot]; - int repeat = VP8LReadBits(br, extra_bits) + repeat_offset; - if (symbol + repeat > num_symbols) { - goto End; - } else { - const int length = use_prev ? prev_code_len : 0; - while (repeat-- > 0) code_lengths[symbol++] = length; - } - } - } - ok = 1; - - End: - if (!ok) dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return ok; -} - -// 'code_lengths' is pre-allocated temporary buffer, used for creating Huffman -// tree. -static int ReadHuffmanCode(int alphabet_size, VP8LDecoder* const dec, - int* const code_lengths, HuffmanCode* const table) { - int ok = 0; - int size = 0; - VP8LBitReader* const br = &dec->br_; - const int simple_code = VP8LReadBits(br, 1); - - memset(code_lengths, 0, alphabet_size * sizeof(*code_lengths)); - - if (simple_code) { // Read symbols, codes & code lengths directly. - const int num_symbols = VP8LReadBits(br, 1) + 1; - const int first_symbol_len_code = VP8LReadBits(br, 1); - // The first code is either 1 bit or 8 bit code. - int symbol = VP8LReadBits(br, (first_symbol_len_code == 0) ? 1 : 8); - code_lengths[symbol] = 1; - // The second code (if present), is always 8 bit long. - if (num_symbols == 2) { - symbol = VP8LReadBits(br, 8); - code_lengths[symbol] = 1; - } - ok = 1; - } else { // Decode Huffman-coded code lengths. - int i; - int code_length_code_lengths[NUM_CODE_LENGTH_CODES] = { 0 }; - const int num_codes = VP8LReadBits(br, 4) + 4; - if (num_codes > NUM_CODE_LENGTH_CODES) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; - } - - for (i = 0; i < num_codes; ++i) { - code_length_code_lengths[kCodeLengthCodeOrder[i]] = VP8LReadBits(br, 3); - } - ok = ReadHuffmanCodeLengths(dec, code_length_code_lengths, alphabet_size, - code_lengths); - } - - ok = ok && !br->eos_; - if (ok) { - size = VP8LBuildHuffmanTable(table, HUFFMAN_TABLE_BITS, - code_lengths, alphabet_size); - } - if (!ok || size == 0) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; - } - return size; -} - -static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, - int color_cache_bits, int allow_recursion) { - int i, j; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - uint32_t* huffman_image = NULL; - HTreeGroup* htree_groups = NULL; - HuffmanCode* huffman_tables = NULL; - HuffmanCode* next = NULL; - int num_htree_groups = 1; - int max_alphabet_size = 0; - int* code_lengths = NULL; - const int table_size = kTableSize[color_cache_bits]; - - if (allow_recursion && VP8LReadBits(br, 1)) { - // use meta Huffman codes. - const int huffman_precision = VP8LReadBits(br, 3) + 2; - const int huffman_xsize = VP8LSubSampleSize(xsize, huffman_precision); - const int huffman_ysize = VP8LSubSampleSize(ysize, huffman_precision); - const int huffman_pixs = huffman_xsize * huffman_ysize; - if (!DecodeImageStream(huffman_xsize, huffman_ysize, 0, dec, - &huffman_image)) { - goto Error; - } - hdr->huffman_subsample_bits_ = huffman_precision; - for (i = 0; i < huffman_pixs; ++i) { - // The huffman data is stored in red and green bytes. - const int group = (huffman_image[i] >> 8) & 0xffff; - huffman_image[i] = group; - if (group >= num_htree_groups) { - num_htree_groups = group + 1; - } - } - } - - if (br->eos_) goto Error; - - // Find maximum alphabet size for the htree group. - for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; ++j) { - int alphabet_size = kAlphabetSize[j]; - if (j == 0 && color_cache_bits > 0) { - alphabet_size += 1 << color_cache_bits; - } - if (max_alphabet_size < alphabet_size) { - max_alphabet_size = alphabet_size; - } - } - - huffman_tables = (HuffmanCode*)WebPSafeMalloc(num_htree_groups * table_size, - sizeof(*huffman_tables)); - htree_groups = VP8LHtreeGroupsNew(num_htree_groups); - code_lengths = (int*)WebPSafeCalloc((uint64_t)max_alphabet_size, - sizeof(*code_lengths)); - - if (htree_groups == NULL || code_lengths == NULL || huffman_tables == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - goto Error; - } - - next = huffman_tables; - for (i = 0; i < num_htree_groups; ++i) { - HTreeGroup* const htree_group = &htree_groups[i]; - HuffmanCode** const htrees = htree_group->htrees; - int size; - int total_size = 0; - int is_trivial_literal = 1; - int max_bits = 0; - for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; ++j) { - int alphabet_size = kAlphabetSize[j]; - htrees[j] = next; - if (j == 0 && color_cache_bits > 0) { - alphabet_size += 1 << color_cache_bits; - } - size = ReadHuffmanCode(alphabet_size, dec, code_lengths, next); - if (size == 0) { - goto Error; - } - if (is_trivial_literal && kLiteralMap[j] == 1) { - is_trivial_literal = (next->bits == 0); - } - total_size += next->bits; - next += size; - if (j <= ALPHA) { - int local_max_bits = code_lengths[0]; - int k; - for (k = 1; k < alphabet_size; ++k) { - if (code_lengths[k] > local_max_bits) { - local_max_bits = code_lengths[k]; - } - } - max_bits += local_max_bits; - } - } - htree_group->is_trivial_literal = is_trivial_literal; - htree_group->is_trivial_code = 0; - if (is_trivial_literal) { - const int red = htrees[RED][0].value; - const int blue = htrees[BLUE][0].value; - const int alpha = htrees[ALPHA][0].value; - htree_group->literal_arb = - ((uint32_t)alpha << 24) | (red << 16) | blue; - if (total_size == 0 && htrees[GREEN][0].value < NUM_LITERAL_CODES) { - htree_group->is_trivial_code = 1; - htree_group->literal_arb |= htrees[GREEN][0].value << 8; - } - } - htree_group->use_packed_table = !htree_group->is_trivial_code && - (max_bits < HUFFMAN_PACKED_BITS); - if (htree_group->use_packed_table) BuildPackedTable(htree_group); - } - WebPSafeFree(code_lengths); - - // All OK. Finalize pointers and return. - hdr->huffman_image_ = huffman_image; - hdr->num_htree_groups_ = num_htree_groups; - hdr->htree_groups_ = htree_groups; - hdr->huffman_tables_ = huffman_tables; - return 1; - - Error: - WebPSafeFree(code_lengths); - WebPSafeFree(huffman_image); - WebPSafeFree(huffman_tables); - VP8LHtreeGroupsFree(htree_groups); - return 0; -} - -//------------------------------------------------------------------------------ -// Scaling. - -static int AllocateAndInitRescaler(VP8LDecoder* const dec, VP8Io* const io) { - const int num_channels = 4; - const int in_width = io->mb_w; - const int out_width = io->scaled_width; - const int in_height = io->mb_h; - const int out_height = io->scaled_height; - const uint64_t work_size = 2 * num_channels * (uint64_t)out_width; - rescaler_t* work; // Rescaler work area. - const uint64_t scaled_data_size = (uint64_t)out_width; - uint32_t* scaled_data; // Temporary storage for scaled BGRA data. - const uint64_t memory_size = sizeof(*dec->rescaler) + - work_size * sizeof(*work) + - scaled_data_size * sizeof(*scaled_data); - uint8_t* memory = (uint8_t*)WebPSafeMalloc(memory_size, sizeof(*memory)); - if (memory == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - assert(dec->rescaler_memory == NULL); - dec->rescaler_memory = memory; - - dec->rescaler = (WebPRescaler*)memory; - memory += sizeof(*dec->rescaler); - work = (rescaler_t*)memory; - memory += work_size * sizeof(*work); - scaled_data = (uint32_t*)memory; - - WebPRescalerInit(dec->rescaler, in_width, in_height, (uint8_t*)scaled_data, - out_width, out_height, 0, num_channels, work); - return 1; -} - -//------------------------------------------------------------------------------ -// Export to ARGB - -// We have special "export" function since we need to convert from BGRA -static int Export(WebPRescaler* const rescaler, WEBP_CSP_MODE colorspace, - int rgba_stride, uint8_t* const rgba) { - uint32_t* const src = (uint32_t*)rescaler->dst; - const int dst_width = rescaler->dst_width; - int num_lines_out = 0; - while (WebPRescalerHasPendingOutput(rescaler)) { - uint8_t* const dst = rgba + num_lines_out * rgba_stride; - WebPRescalerExportRow(rescaler); - WebPMultARGBRow(src, dst_width, 1); - VP8LConvertFromBGRA(src, dst_width, colorspace, dst); - ++num_lines_out; - } - return num_lines_out; -} - -// Emit scaled rows. -static int EmitRescaledRowsRGBA(const VP8LDecoder* const dec, - uint8_t* in, int in_stride, int mb_h, - uint8_t* const out, int out_stride) { - const WEBP_CSP_MODE colorspace = dec->output_->colorspace; - int num_lines_in = 0; - int num_lines_out = 0; - while (num_lines_in < mb_h) { - uint8_t* const row_in = in + num_lines_in * in_stride; - uint8_t* const row_out = out + num_lines_out * out_stride; - const int lines_left = mb_h - num_lines_in; - const int needed_lines = WebPRescaleNeededLines(dec->rescaler, lines_left); - assert(needed_lines > 0 && needed_lines <= lines_left); - WebPMultARGBRows(row_in, in_stride, - dec->rescaler->src_width, needed_lines, 0); - WebPRescalerImport(dec->rescaler, lines_left, row_in, in_stride); - num_lines_in += needed_lines; - num_lines_out += Export(dec->rescaler, colorspace, out_stride, row_out); - } - return num_lines_out; -} - -// Emit rows without any scaling. -static int EmitRows(WEBP_CSP_MODE colorspace, - const uint8_t* row_in, int in_stride, - int mb_w, int mb_h, - uint8_t* const out, int out_stride) { - int lines = mb_h; - uint8_t* row_out = out; - while (lines-- > 0) { - VP8LConvertFromBGRA((const uint32_t*)row_in, mb_w, colorspace, row_out); - row_in += in_stride; - row_out += out_stride; - } - return mb_h; // Num rows out == num rows in. -} - -//------------------------------------------------------------------------------ -// Export to YUVA - -static void ConvertToYUVA(const uint32_t* const src, int width, int y_pos, - const WebPDecBuffer* const output) { - const WebPYUVABuffer* const buf = &output->u.YUVA; - - // first, the luma plane - WebPConvertARGBToY(src, buf->y + y_pos * buf->y_stride, width); - - // then U/V planes - { - uint8_t* const u = buf->u + (y_pos >> 1) * buf->u_stride; - uint8_t* const v = buf->v + (y_pos >> 1) * buf->v_stride; - // even lines: store values - // odd lines: average with previous values - WebPConvertARGBToUV(src, u, v, width, !(y_pos & 1)); - } - // Lastly, store alpha if needed. - if (buf->a != NULL) { - uint8_t* const a = buf->a + y_pos * buf->a_stride; -#if defined(WORDS_BIGENDIAN) - WebPExtractAlpha((uint8_t*)src + 0, 0, width, 1, a, 0); -#else - WebPExtractAlpha((uint8_t*)src + 3, 0, width, 1, a, 0); -#endif - } -} - -static int ExportYUVA(const VP8LDecoder* const dec, int y_pos) { - WebPRescaler* const rescaler = dec->rescaler; - uint32_t* const src = (uint32_t*)rescaler->dst; - const int dst_width = rescaler->dst_width; - int num_lines_out = 0; - while (WebPRescalerHasPendingOutput(rescaler)) { - WebPRescalerExportRow(rescaler); - WebPMultARGBRow(src, dst_width, 1); - ConvertToYUVA(src, dst_width, y_pos, dec->output_); - ++y_pos; - ++num_lines_out; - } - return num_lines_out; -} - -static int EmitRescaledRowsYUVA(const VP8LDecoder* const dec, - uint8_t* in, int in_stride, int mb_h) { - int num_lines_in = 0; - int y_pos = dec->last_out_row_; - while (num_lines_in < mb_h) { - const int lines_left = mb_h - num_lines_in; - const int needed_lines = WebPRescaleNeededLines(dec->rescaler, lines_left); - WebPMultARGBRows(in, in_stride, dec->rescaler->src_width, needed_lines, 0); - WebPRescalerImport(dec->rescaler, lines_left, in, in_stride); - num_lines_in += needed_lines; - in += needed_lines * in_stride; - y_pos += ExportYUVA(dec, y_pos); - } - return y_pos; -} - -static int EmitRowsYUVA(const VP8LDecoder* const dec, - const uint8_t* in, int in_stride, - int mb_w, int num_rows) { - int y_pos = dec->last_out_row_; - while (num_rows-- > 0) { - ConvertToYUVA((const uint32_t*)in, mb_w, y_pos, dec->output_); - in += in_stride; - ++y_pos; - } - return y_pos; -} - -//------------------------------------------------------------------------------ -// Cropping. - -// Sets io->mb_y, io->mb_h & io->mb_w according to start row, end row and -// crop options. Also updates the input data pointer, so that it points to the -// start of the cropped window. Note that pixels are in ARGB format even if -// 'in_data' is uint8_t*. -// Returns true if the crop window is not empty. -static int SetCropWindow(VP8Io* const io, int y_start, int y_end, - uint8_t** const in_data, int pixel_stride) { - assert(y_start < y_end); - assert(io->crop_left < io->crop_right); - if (y_end > io->crop_bottom) { - y_end = io->crop_bottom; // make sure we don't overflow on last row. - } - if (y_start < io->crop_top) { - const int delta = io->crop_top - y_start; - y_start = io->crop_top; - *in_data += delta * pixel_stride; - } - if (y_start >= y_end) return 0; // Crop window is empty. - - *in_data += io->crop_left * sizeof(uint32_t); - - io->mb_y = y_start - io->crop_top; - io->mb_w = io->crop_right - io->crop_left; - io->mb_h = y_end - y_start; - return 1; // Non-empty crop window. -} - -//------------------------------------------------------------------------------ - -static WEBP_INLINE int GetMetaIndex( - const uint32_t* const image, int xsize, int bits, int x, int y) { - if (bits == 0) return 0; - return image[xsize * (y >> bits) + (x >> bits)]; -} - -static WEBP_INLINE HTreeGroup* GetHtreeGroupForPos(VP8LMetadata* const hdr, - int x, int y) { - const int meta_index = GetMetaIndex(hdr->huffman_image_, hdr->huffman_xsize_, - hdr->huffman_subsample_bits_, x, y); - assert(meta_index < hdr->num_htree_groups_); - return hdr->htree_groups_ + meta_index; -} - -//------------------------------------------------------------------------------ -// Main loop, with custom row-processing function - -typedef void (*ProcessRowsFunc)(VP8LDecoder* const dec, int row); - -static void ApplyInverseTransforms(VP8LDecoder* const dec, int num_rows, - const uint32_t* const rows) { - int n = dec->next_transform_; - const int cache_pixs = dec->width_ * num_rows; - const int start_row = dec->last_row_; - const int end_row = start_row + num_rows; - const uint32_t* rows_in = rows; - uint32_t* const rows_out = dec->argb_cache_; - - // Inverse transforms. - // TODO: most transforms only need to operate on the cropped region only. - memcpy(rows_out, rows_in, cache_pixs * sizeof(*rows_out)); - while (n-- > 0) { - VP8LTransform* const transform = &dec->transforms_[n]; - VP8LInverseTransform(transform, start_row, end_row, rows_in, rows_out); - rows_in = rows_out; - } -} - -// Processes (transforms, scales & color-converts) the rows decoded after the -// last call. -static void ProcessRows(VP8LDecoder* const dec, int row) { - const uint32_t* const rows = dec->pixels_ + dec->width_ * dec->last_row_; - const int num_rows = row - dec->last_row_; - - assert(row <= dec->io_->crop_bottom); - // We can't process more than NUM_ARGB_CACHE_ROWS at a time (that's the size - // of argb_cache_), but we currently don't need more than that. - assert(num_rows <= NUM_ARGB_CACHE_ROWS); - if (num_rows > 0) { // Emit output. - VP8Io* const io = dec->io_; - uint8_t* rows_data = (uint8_t*)dec->argb_cache_; - const int in_stride = io->width * sizeof(uint32_t); // in unit of RGBA - - ApplyInverseTransforms(dec, num_rows, rows); - if (!SetCropWindow(io, dec->last_row_, row, &rows_data, in_stride)) { - // Nothing to output (this time). - } else { - const WebPDecBuffer* const output = dec->output_; - if (WebPIsRGBMode(output->colorspace)) { // convert to RGBA - const WebPRGBABuffer* const buf = &output->u.RGBA; - uint8_t* const rgba = buf->rgba + dec->last_out_row_ * buf->stride; - const int num_rows_out = io->use_scaling ? - EmitRescaledRowsRGBA(dec, rows_data, in_stride, io->mb_h, - rgba, buf->stride) : - EmitRows(output->colorspace, rows_data, in_stride, - io->mb_w, io->mb_h, rgba, buf->stride); - // Update 'last_out_row_'. - dec->last_out_row_ += num_rows_out; - } else { // convert to YUVA - dec->last_out_row_ = io->use_scaling ? - EmitRescaledRowsYUVA(dec, rows_data, in_stride, io->mb_h) : - EmitRowsYUVA(dec, rows_data, in_stride, io->mb_w, io->mb_h); - } - assert(dec->last_out_row_ <= output->height); - } - } - - // Update 'last_row_'. - dec->last_row_ = row; - assert(dec->last_row_ <= dec->height_); -} - -// Row-processing for the special case when alpha data contains only one -// transform (color indexing), and trivial non-green literals. -static int Is8bOptimizable(const VP8LMetadata* const hdr) { - int i; - if (hdr->color_cache_size_ > 0) return 0; - // When the Huffman tree contains only one symbol, we can skip the - // call to ReadSymbol() for red/blue/alpha channels. - for (i = 0; i < hdr->num_htree_groups_; ++i) { - HuffmanCode** const htrees = hdr->htree_groups_[i].htrees; - if (htrees[RED][0].bits > 0) return 0; - if (htrees[BLUE][0].bits > 0) return 0; - if (htrees[ALPHA][0].bits > 0) return 0; - } - return 1; -} - -static void AlphaApplyFilter(ALPHDecoder* const alph_dec, - int first_row, int last_row, - uint8_t* out, int stride) { - if (alph_dec->filter_ != WEBP_FILTER_NONE) { - int y; - const uint8_t* prev_line = alph_dec->prev_line_; - assert(WebPUnfilters[alph_dec->filter_] != NULL); - for (y = first_row; y < last_row; ++y) { - WebPUnfilters[alph_dec->filter_](prev_line, out, out, stride); - prev_line = out; - out += stride; - } - alph_dec->prev_line_ = prev_line; - } -} - -static void ExtractPalettedAlphaRows(VP8LDecoder* const dec, int last_row) { - // For vertical and gradient filtering, we need to decode the part above the - // crop_top row, in order to have the correct spatial predictors. - ALPHDecoder* const alph_dec = (ALPHDecoder*)dec->io_->opaque; - const int top_row = - (alph_dec->filter_ == WEBP_FILTER_NONE || - alph_dec->filter_ == WEBP_FILTER_HORIZONTAL) ? dec->io_->crop_top - : dec->last_row_; - const int first_row = (dec->last_row_ < top_row) ? top_row : dec->last_row_; - assert(last_row <= dec->io_->crop_bottom); - if (last_row > first_row) { - // Special method for paletted alpha data. We only process the cropped area. - const int width = dec->io_->width; - uint8_t* out = alph_dec->output_ + width * first_row; - const uint8_t* const in = - (uint8_t*)dec->pixels_ + dec->width_ * first_row; - VP8LTransform* const transform = &dec->transforms_[0]; - assert(dec->next_transform_ == 1); - assert(transform->type_ == COLOR_INDEXING_TRANSFORM); - VP8LColorIndexInverseTransformAlpha(transform, first_row, last_row, - in, out); - AlphaApplyFilter(alph_dec, first_row, last_row, out, width); - } - dec->last_row_ = dec->last_out_row_ = last_row; -} - -//------------------------------------------------------------------------------ -// Helper functions for fast pattern copy (8b and 32b) - -// cyclic rotation of pattern word -static WEBP_INLINE uint32_t Rotate8b(uint32_t V) { -#if defined(WORDS_BIGENDIAN) - return ((V & 0xff000000u) >> 24) | (V << 8); -#else - return ((V & 0xffu) << 24) | (V >> 8); -#endif -} - -// copy 1, 2 or 4-bytes pattern -static WEBP_INLINE void CopySmallPattern8b(const uint8_t* src, uint8_t* dst, - int length, uint32_t pattern) { - int i; - // align 'dst' to 4-bytes boundary. Adjust the pattern along the way. - while ((uintptr_t)dst & 3) { - *dst++ = *src++; - pattern = Rotate8b(pattern); - --length; - } - // Copy the pattern 4 bytes at a time. - for (i = 0; i < (length >> 2); ++i) { - ((uint32_t*)dst)[i] = pattern; - } - // Finish with left-overs. 'pattern' is still correctly positioned, - // so no Rotate8b() call is needed. - for (i <<= 2; i < length; ++i) { - dst[i] = src[i]; - } -} - -static WEBP_INLINE void CopyBlock8b(uint8_t* const dst, int dist, int length) { - const uint8_t* src = dst - dist; - if (length >= 8) { - uint32_t pattern = 0; - switch (dist) { - case 1: - pattern = src[0]; -#if defined(__arm__) || defined(_M_ARM) // arm doesn't like multiply that much - pattern |= pattern << 8; - pattern |= pattern << 16; -#elif defined(WEBP_USE_MIPS_DSP_R2) - __asm__ volatile ("replv.qb %0, %0" : "+r"(pattern)); -#else - pattern = 0x01010101u * pattern; -#endif - break; - case 2: - memcpy(&pattern, src, sizeof(uint16_t)); -#if defined(__arm__) || defined(_M_ARM) - pattern |= pattern << 16; -#elif defined(WEBP_USE_MIPS_DSP_R2) - __asm__ volatile ("replv.ph %0, %0" : "+r"(pattern)); -#else - pattern = 0x00010001u * pattern; -#endif - break; - case 4: - memcpy(&pattern, src, sizeof(uint32_t)); - break; - default: - goto Copy; - break; - } - CopySmallPattern8b(src, dst, length, pattern); - return; - } - Copy: - if (dist >= length) { // no overlap -> use memcpy() - memcpy(dst, src, length * sizeof(*dst)); - } else { - int i; - for (i = 0; i < length; ++i) dst[i] = src[i]; - } -} - -// copy pattern of 1 or 2 uint32_t's -static WEBP_INLINE void CopySmallPattern32b(const uint32_t* src, - uint32_t* dst, - int length, uint64_t pattern) { - int i; - if ((uintptr_t)dst & 4) { // Align 'dst' to 8-bytes boundary. - *dst++ = *src++; - pattern = (pattern >> 32) | (pattern << 32); - --length; - } - assert(0 == ((uintptr_t)dst & 7)); - for (i = 0; i < (length >> 1); ++i) { - ((uint64_t*)dst)[i] = pattern; // Copy the pattern 8 bytes at a time. - } - if (length & 1) { // Finish with left-over. - dst[i << 1] = src[i << 1]; - } -} - -static WEBP_INLINE void CopyBlock32b(uint32_t* const dst, - int dist, int length) { - const uint32_t* const src = dst - dist; - if (dist <= 2 && length >= 4 && ((uintptr_t)dst & 3) == 0) { - uint64_t pattern; - if (dist == 1) { - pattern = (uint64_t)src[0]; - pattern |= pattern << 32; - } else { - memcpy(&pattern, src, sizeof(pattern)); - } - CopySmallPattern32b(src, dst, length, pattern); - } else if (dist >= length) { // no overlap - memcpy(dst, src, length * sizeof(*dst)); - } else { - int i; - for (i = 0; i < length; ++i) dst[i] = src[i]; - } -} - -//------------------------------------------------------------------------------ - -static int DecodeAlphaData(VP8LDecoder* const dec, uint8_t* const data, - int width, int height, int last_row) { - int ok = 1; - int row = dec->last_pixel_ / width; - int col = dec->last_pixel_ % width; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - int pos = dec->last_pixel_; // current position - const int end = width * height; // End of data - const int last = width * last_row; // Last pixel to decode - const int len_code_limit = NUM_LITERAL_CODES + NUM_LENGTH_CODES; - const int mask = hdr->huffman_mask_; - const HTreeGroup* htree_group = - (pos < last) ? GetHtreeGroupForPos(hdr, col, row) : NULL; - assert(pos <= end); - assert(last_row <= height); - assert(Is8bOptimizable(hdr)); - - while (!br->eos_ && pos < last) { - int code; - // Only update when changing tile. - if ((col & mask) == 0) { - htree_group = GetHtreeGroupForPos(hdr, col, row); - } - assert(htree_group != NULL); - VP8LFillBitWindow(br); - code = ReadSymbol(htree_group->htrees[GREEN], br); - if (code < NUM_LITERAL_CODES) { // Literal - data[pos] = code; - ++pos; - ++col; - if (col >= width) { - col = 0; - ++row; - if (row <= last_row && (row % NUM_ARGB_CACHE_ROWS == 0)) { - ExtractPalettedAlphaRows(dec, row); - } - } - } else if (code < len_code_limit) { // Backward reference - int dist_code, dist; - const int length_sym = code - NUM_LITERAL_CODES; - const int length = GetCopyLength(length_sym, br); - const int dist_symbol = ReadSymbol(htree_group->htrees[DIST], br); - VP8LFillBitWindow(br); - dist_code = GetCopyDistance(dist_symbol, br); - dist = PlaneCodeToDistance(width, dist_code); - if (pos >= dist && end - pos >= length) { - CopyBlock8b(data + pos, dist, length); - } else { - ok = 0; - goto End; - } - pos += length; - col += length; - while (col >= width) { - col -= width; - ++row; - if (row <= last_row && (row % NUM_ARGB_CACHE_ROWS == 0)) { - ExtractPalettedAlphaRows(dec, row); - } - } - if (pos < last && (col & mask)) { - htree_group = GetHtreeGroupForPos(hdr, col, row); - } - } else { // Not reached - ok = 0; - goto End; - } - assert(br->eos_ == VP8LIsEndOfStream(br)); - } - // Process the remaining rows corresponding to last row-block. - ExtractPalettedAlphaRows(dec, row > last_row ? last_row : row); - - End: - if (!ok || (br->eos_ && pos < end)) { - ok = 0; - dec->status_ = br->eos_ ? VP8_STATUS_SUSPENDED - : VP8_STATUS_BITSTREAM_ERROR; - } else { - dec->last_pixel_ = pos; - } - return ok; -} - -static void SaveState(VP8LDecoder* const dec, int last_pixel) { - assert(dec->incremental_); - dec->saved_br_ = dec->br_; - dec->saved_last_pixel_ = last_pixel; - if (dec->hdr_.color_cache_size_ > 0) { - VP8LColorCacheCopy(&dec->hdr_.color_cache_, &dec->hdr_.saved_color_cache_); - } -} - -static void RestoreState(VP8LDecoder* const dec) { - assert(dec->br_.eos_); - dec->status_ = VP8_STATUS_SUSPENDED; - dec->br_ = dec->saved_br_; - dec->last_pixel_ = dec->saved_last_pixel_; - if (dec->hdr_.color_cache_size_ > 0) { - VP8LColorCacheCopy(&dec->hdr_.saved_color_cache_, &dec->hdr_.color_cache_); - } -} - -#define SYNC_EVERY_N_ROWS 8 // minimum number of rows between check-points -static int DecodeImageData(VP8LDecoder* const dec, uint32_t* const data, - int width, int height, int last_row, - ProcessRowsFunc process_func) { - int row = dec->last_pixel_ / width; - int col = dec->last_pixel_ % width; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - uint32_t* src = data + dec->last_pixel_; - uint32_t* last_cached = src; - uint32_t* const src_end = data + width * height; // End of data - uint32_t* const src_last = data + width * last_row; // Last pixel to decode - const int len_code_limit = NUM_LITERAL_CODES + NUM_LENGTH_CODES; - const int color_cache_limit = len_code_limit + hdr->color_cache_size_; - int next_sync_row = dec->incremental_ ? row : 1 << 24; - VP8LColorCache* const color_cache = - (hdr->color_cache_size_ > 0) ? &hdr->color_cache_ : NULL; - const int mask = hdr->huffman_mask_; - const HTreeGroup* htree_group = - (src < src_last) ? GetHtreeGroupForPos(hdr, col, row) : NULL; - assert(dec->last_row_ < last_row); - assert(src_last <= src_end); - - while (src < src_last) { - int code; - if (row >= next_sync_row) { - SaveState(dec, (int)(src - data)); - next_sync_row = row + SYNC_EVERY_N_ROWS; - } - // Only update when changing tile. Note we could use this test: - // if "((((prev_col ^ col) | prev_row ^ row)) > mask)" -> tile changed - // but that's actually slower and needs storing the previous col/row. - if ((col & mask) == 0) { - htree_group = GetHtreeGroupForPos(hdr, col, row); - } - assert(htree_group != NULL); - if (htree_group->is_trivial_code) { - *src = htree_group->literal_arb; - goto AdvanceByOne; - } - VP8LFillBitWindow(br); - if (htree_group->use_packed_table) { - code = ReadPackedSymbols(htree_group, br, src); - if (code == PACKED_NON_LITERAL_CODE) goto AdvanceByOne; - } else { - code = ReadSymbol(htree_group->htrees[GREEN], br); - } - if (br->eos_) break; // early out - if (code < NUM_LITERAL_CODES) { // Literal - if (htree_group->is_trivial_literal) { - *src = htree_group->literal_arb | (code << 8); - } else { - int red, blue, alpha; - red = ReadSymbol(htree_group->htrees[RED], br); - VP8LFillBitWindow(br); - blue = ReadSymbol(htree_group->htrees[BLUE], br); - alpha = ReadSymbol(htree_group->htrees[ALPHA], br); - if (br->eos_) break; - *src = ((uint32_t)alpha << 24) | (red << 16) | (code << 8) | blue; - } - AdvanceByOne: - ++src; - ++col; - if (col >= width) { - col = 0; - ++row; - if (process_func != NULL) { - if (row <= last_row && (row % NUM_ARGB_CACHE_ROWS == 0)) { - process_func(dec, row); - } - } - if (color_cache != NULL) { - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - } - } - } else if (code < len_code_limit) { // Backward reference - int dist_code, dist; - const int length_sym = code - NUM_LITERAL_CODES; - const int length = GetCopyLength(length_sym, br); - const int dist_symbol = ReadSymbol(htree_group->htrees[DIST], br); - VP8LFillBitWindow(br); - dist_code = GetCopyDistance(dist_symbol, br); - dist = PlaneCodeToDistance(width, dist_code); - if (br->eos_) break; - if (src - data < (ptrdiff_t)dist || src_end - src < (ptrdiff_t)length) { - goto Error; - } else { - CopyBlock32b(src, dist, length); - } - src += length; - col += length; - while (col >= width) { - col -= width; - ++row; - if (process_func != NULL) { - if (row <= last_row && (row % NUM_ARGB_CACHE_ROWS == 0)) { - process_func(dec, row); - } - } - } - // Because of the check done above (before 'src' was incremented by - // 'length'), the following holds true. - assert(src <= src_end); - if (col & mask) htree_group = GetHtreeGroupForPos(hdr, col, row); - if (color_cache != NULL) { - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - } - } else if (code < color_cache_limit) { // Color cache - const int key = code - len_code_limit; - assert(color_cache != NULL); - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - *src = VP8LColorCacheLookup(color_cache, key); - goto AdvanceByOne; - } else { // Not reached - goto Error; - } - assert(br->eos_ == VP8LIsEndOfStream(br)); - } - - if (dec->incremental_ && br->eos_ && src < src_end) { - RestoreState(dec); - } else if (!br->eos_) { - // Process the remaining rows corresponding to last row-block. - if (process_func != NULL) { - process_func(dec, row > last_row ? last_row : row); - } - dec->status_ = VP8_STATUS_OK; - dec->last_pixel_ = (int)(src - data); // end-of-scan marker - } else { - // if not incremental, and we are past the end of buffer (eos_=1), then this - // is a real bitstream error. - goto Error; - } - return 1; - - Error: - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; -} - -// ----------------------------------------------------------------------------- -// VP8LTransform - -static void ClearTransform(VP8LTransform* const transform) { - WebPSafeFree(transform->data_); - transform->data_ = NULL; -} - -// For security reason, we need to remap the color map to span -// the total possible bundled values, and not just the num_colors. -static int ExpandColorMap(int num_colors, VP8LTransform* const transform) { - int i; - const int final_num_colors = 1 << (8 >> transform->bits_); - uint32_t* const new_color_map = - (uint32_t*)WebPSafeMalloc((uint64_t)final_num_colors, - sizeof(*new_color_map)); - if (new_color_map == NULL) { - return 0; - } else { - uint8_t* const data = (uint8_t*)transform->data_; - uint8_t* const new_data = (uint8_t*)new_color_map; - new_color_map[0] = transform->data_[0]; - for (i = 4; i < 4 * num_colors; ++i) { - // Equivalent to AddPixelEq(), on a byte-basis. - new_data[i] = (data[i] + new_data[i - 4]) & 0xff; - } - for (; i < 4 * final_num_colors; ++i) - new_data[i] = 0; // black tail. - WebPSafeFree(transform->data_); - transform->data_ = new_color_map; - } - return 1; -} - -static int ReadTransform(int* const xsize, int const* ysize, - VP8LDecoder* const dec) { - int ok = 1; - VP8LBitReader* const br = &dec->br_; - VP8LTransform* transform = &dec->transforms_[dec->next_transform_]; - const VP8LImageTransformType type = - (VP8LImageTransformType)VP8LReadBits(br, 2); - - // Each transform type can only be present once in the stream. - if (dec->transforms_seen_ & (1U << type)) { - return 0; // Already there, let's not accept the second same transform. - } - dec->transforms_seen_ |= (1U << type); - - transform->type_ = type; - transform->xsize_ = *xsize; - transform->ysize_ = *ysize; - transform->data_ = NULL; - ++dec->next_transform_; - assert(dec->next_transform_ <= NUM_TRANSFORMS); - - switch (type) { - case PREDICTOR_TRANSFORM: - case CROSS_COLOR_TRANSFORM: - transform->bits_ = VP8LReadBits(br, 3) + 2; - ok = DecodeImageStream(VP8LSubSampleSize(transform->xsize_, - transform->bits_), - VP8LSubSampleSize(transform->ysize_, - transform->bits_), - 0, dec, &transform->data_); - break; - case COLOR_INDEXING_TRANSFORM: { - const int num_colors = VP8LReadBits(br, 8) + 1; - const int bits = (num_colors > 16) ? 0 - : (num_colors > 4) ? 1 - : (num_colors > 2) ? 2 - : 3; - *xsize = VP8LSubSampleSize(transform->xsize_, bits); - transform->bits_ = bits; - ok = DecodeImageStream(num_colors, 1, 0, dec, &transform->data_); - ok = ok && ExpandColorMap(num_colors, transform); - break; - } - case SUBTRACT_GREEN: - break; - default: - assert(0); // can't happen - break; - } - - return ok; -} - -// ----------------------------------------------------------------------------- -// VP8LMetadata - -static void InitMetadata(VP8LMetadata* const hdr) { - assert(hdr != NULL); - memset(hdr, 0, sizeof(*hdr)); -} - -static void ClearMetadata(VP8LMetadata* const hdr) { - assert(hdr != NULL); - - WebPSafeFree(hdr->huffman_image_); - WebPSafeFree(hdr->huffman_tables_); - VP8LHtreeGroupsFree(hdr->htree_groups_); - VP8LColorCacheClear(&hdr->color_cache_); - VP8LColorCacheClear(&hdr->saved_color_cache_); - InitMetadata(hdr); -} - -// ----------------------------------------------------------------------------- -// VP8LDecoder - -VP8LDecoder* VP8LNew(void) { - VP8LDecoder* const dec = (VP8LDecoder*)WebPSafeCalloc(1ULL, sizeof(*dec)); - if (dec == NULL) return NULL; - dec->status_ = VP8_STATUS_OK; - dec->state_ = READ_DIM; - - VP8LDspInit(); // Init critical function pointers. - - return dec; -} - -void VP8LClear(VP8LDecoder* const dec) { - int i; - if (dec == NULL) return; - ClearMetadata(&dec->hdr_); - - WebPSafeFree(dec->pixels_); - dec->pixels_ = NULL; - for (i = 0; i < dec->next_transform_; ++i) { - ClearTransform(&dec->transforms_[i]); - } - dec->next_transform_ = 0; - dec->transforms_seen_ = 0; - - WebPSafeFree(dec->rescaler_memory); - dec->rescaler_memory = NULL; - - dec->output_ = NULL; // leave no trace behind -} - -void VP8LDelete(VP8LDecoder* const dec) { - if (dec != NULL) { - VP8LClear(dec); - WebPSafeFree(dec); - } -} - -static void UpdateDecoder(VP8LDecoder* const dec, int width, int height) { - VP8LMetadata* const hdr = &dec->hdr_; - const int num_bits = hdr->huffman_subsample_bits_; - dec->width_ = width; - dec->height_ = height; - - hdr->huffman_xsize_ = VP8LSubSampleSize(width, num_bits); - hdr->huffman_mask_ = (num_bits == 0) ? ~0 : (1 << num_bits) - 1; -} - -static int DecodeImageStream(int xsize, int ysize, - int is_level0, - VP8LDecoder* const dec, - uint32_t** const decoded_data) { - int ok = 1; - int transform_xsize = xsize; - int transform_ysize = ysize; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - uint32_t* data = NULL; - int color_cache_bits = 0; - - // Read the transforms (may recurse). - if (is_level0) { - while (ok && VP8LReadBits(br, 1)) { - ok = ReadTransform(&transform_xsize, &transform_ysize, dec); - } - } - - // Color cache - if (ok && VP8LReadBits(br, 1)) { - color_cache_bits = VP8LReadBits(br, 4); - ok = (color_cache_bits >= 1 && color_cache_bits <= MAX_CACHE_BITS); - if (!ok) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } - } - - // Read the Huffman codes (may recurse). - ok = ok && ReadHuffmanCodes(dec, transform_xsize, transform_ysize, - color_cache_bits, is_level0); - if (!ok) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } - - // Finish setting up the color-cache - if (color_cache_bits > 0) { - hdr->color_cache_size_ = 1 << color_cache_bits; - if (!VP8LColorCacheInit(&hdr->color_cache_, color_cache_bits)) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - ok = 0; - goto End; - } - } else { - hdr->color_cache_size_ = 0; - } - UpdateDecoder(dec, transform_xsize, transform_ysize); - - if (is_level0) { // level 0 complete - dec->state_ = READ_HDR; - goto End; - } - - { - const uint64_t total_size = (uint64_t)transform_xsize * transform_ysize; - data = (uint32_t*)WebPSafeMalloc(total_size, sizeof(*data)); - if (data == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - ok = 0; - goto End; - } - } - - // Use the Huffman trees to decode the LZ77 encoded data. - ok = DecodeImageData(dec, data, transform_xsize, transform_ysize, - transform_ysize, NULL); - ok = ok && !br->eos_; - - End: - if (!ok) { - WebPSafeFree(data); - ClearMetadata(hdr); - } else { - if (decoded_data != NULL) { - *decoded_data = data; - } else { - // We allocate image data in this function only for transforms. At level 0 - // (that is: not the transforms), we shouldn't have allocated anything. - assert(data == NULL); - assert(is_level0); - } - dec->last_pixel_ = 0; // Reset for future DECODE_DATA_FUNC() calls. - if (!is_level0) ClearMetadata(hdr); // Clean up temporary data behind. - } - return ok; -} - -//------------------------------------------------------------------------------ -// Allocate internal buffers dec->pixels_ and dec->argb_cache_. -static int AllocateInternalBuffers32b(VP8LDecoder* const dec, int final_width) { - const uint64_t num_pixels = (uint64_t)dec->width_ * dec->height_; - // Scratch buffer corresponding to top-prediction row for transforming the - // first row in the row-blocks. Not needed for paletted alpha. - const uint64_t cache_top_pixels = (uint16_t)final_width; - // Scratch buffer for temporary BGRA storage. Not needed for paletted alpha. - const uint64_t cache_pixels = (uint64_t)final_width * NUM_ARGB_CACHE_ROWS; - const uint64_t total_num_pixels = - num_pixels + cache_top_pixels + cache_pixels; - - assert(dec->width_ <= final_width); - dec->pixels_ = (uint32_t*)WebPSafeMalloc(total_num_pixels, sizeof(uint32_t)); - if (dec->pixels_ == NULL) { - dec->argb_cache_ = NULL; // for sanity check - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - dec->argb_cache_ = dec->pixels_ + num_pixels + cache_top_pixels; - return 1; -} - -static int AllocateInternalBuffers8b(VP8LDecoder* const dec) { - const uint64_t total_num_pixels = (uint64_t)dec->width_ * dec->height_; - dec->argb_cache_ = NULL; // for sanity check - dec->pixels_ = (uint32_t*)WebPSafeMalloc(total_num_pixels, sizeof(uint8_t)); - if (dec->pixels_ == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - return 1; -} - -//------------------------------------------------------------------------------ - -// Special row-processing that only stores the alpha data. -static void ExtractAlphaRows(VP8LDecoder* const dec, int last_row) { - int cur_row = dec->last_row_; - int num_rows = last_row - cur_row; - const uint32_t* in = dec->pixels_ + dec->width_ * cur_row; - - assert(last_row <= dec->io_->crop_bottom); - while (num_rows > 0) { - const int num_rows_to_process = - (num_rows > NUM_ARGB_CACHE_ROWS) ? NUM_ARGB_CACHE_ROWS : num_rows; - // Extract alpha (which is stored in the green plane). - ALPHDecoder* const alph_dec = (ALPHDecoder*)dec->io_->opaque; - uint8_t* const output = alph_dec->output_; - const int width = dec->io_->width; // the final width (!= dec->width_) - const int cache_pixs = width * num_rows_to_process; - uint8_t* const dst = output + width * cur_row; - const uint32_t* const src = dec->argb_cache_; - int i; - ApplyInverseTransforms(dec, num_rows_to_process, in); - for (i = 0; i < cache_pixs; ++i) dst[i] = (src[i] >> 8) & 0xff; - AlphaApplyFilter(alph_dec, - cur_row, cur_row + num_rows_to_process, dst, width); - num_rows -= num_rows_to_process; - in += num_rows_to_process * dec->width_; - cur_row += num_rows_to_process; - } - assert(cur_row == last_row); - dec->last_row_ = dec->last_out_row_ = last_row; -} - -int VP8LDecodeAlphaHeader(ALPHDecoder* const alph_dec, - const uint8_t* const data, size_t data_size) { - int ok = 0; - VP8LDecoder* dec = VP8LNew(); - - if (dec == NULL) return 0; - - assert(alph_dec != NULL); - alph_dec->vp8l_dec_ = dec; - - dec->width_ = alph_dec->width_; - dec->height_ = alph_dec->height_; - dec->io_ = &alph_dec->io_; - dec->io_->opaque = alph_dec; - dec->io_->width = alph_dec->width_; - dec->io_->height = alph_dec->height_; - - dec->status_ = VP8_STATUS_OK; - VP8LInitBitReader(&dec->br_, data, data_size); - - if (!DecodeImageStream(alph_dec->width_, alph_dec->height_, 1, dec, NULL)) { - goto Err; - } - - // Special case: if alpha data uses only the color indexing transform and - // doesn't use color cache (a frequent case), we will use DecodeAlphaData() - // method that only needs allocation of 1 byte per pixel (alpha channel). - if (dec->next_transform_ == 1 && - dec->transforms_[0].type_ == COLOR_INDEXING_TRANSFORM && - Is8bOptimizable(&dec->hdr_)) { - alph_dec->use_8b_decode_ = 1; - ok = AllocateInternalBuffers8b(dec); - } else { - // Allocate internal buffers (note that dec->width_ may have changed here). - alph_dec->use_8b_decode_ = 0; - ok = AllocateInternalBuffers32b(dec, alph_dec->width_); - } - - if (!ok) goto Err; - - return 1; - - Err: - VP8LDelete(alph_dec->vp8l_dec_); - alph_dec->vp8l_dec_ = NULL; - return 0; -} - -int VP8LDecodeAlphaImageStream(ALPHDecoder* const alph_dec, int last_row) { - VP8LDecoder* const dec = alph_dec->vp8l_dec_; - assert(dec != NULL); - assert(last_row <= dec->height_); - - if (dec->last_row_ >= last_row) { - return 1; // done - } - - // Decode (with special row processing). - return alph_dec->use_8b_decode_ ? - DecodeAlphaData(dec, (uint8_t*)dec->pixels_, dec->width_, dec->height_, - last_row) : - DecodeImageData(dec, dec->pixels_, dec->width_, dec->height_, - last_row, ExtractAlphaRows); -} - -//------------------------------------------------------------------------------ - -int VP8LDecodeHeader(VP8LDecoder* const dec, VP8Io* const io) { - int width, height, has_alpha; - - if (dec == NULL) return 0; - if (io == NULL) { - dec->status_ = VP8_STATUS_INVALID_PARAM; - return 0; - } - - dec->io_ = io; - dec->status_ = VP8_STATUS_OK; - VP8LInitBitReader(&dec->br_, io->data, io->data_size); - if (!ReadImageInfo(&dec->br_, &width, &height, &has_alpha)) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto Error; - } - dec->state_ = READ_DIM; - io->width = width; - io->height = height; - - if (!DecodeImageStream(width, height, 1, dec, NULL)) goto Error; - return 1; - - Error: - VP8LClear(dec); - assert(dec->status_ != VP8_STATUS_OK); - return 0; -} - -int VP8LDecodeImage(VP8LDecoder* const dec) { - VP8Io* io = NULL; - WebPDecParams* params = NULL; - - // Sanity checks. - if (dec == NULL) return 0; - - assert(dec->hdr_.huffman_tables_ != NULL); - assert(dec->hdr_.htree_groups_ != NULL); - assert(dec->hdr_.num_htree_groups_ > 0); - - io = dec->io_; - assert(io != NULL); - params = (WebPDecParams*)io->opaque; - assert(params != NULL); - - // Initialization. - if (dec->state_ != READ_DATA) { - dec->output_ = params->output; - assert(dec->output_ != NULL); - - if (!WebPIoInitFromOptions(params->options, io, MODE_BGRA)) { - dec->status_ = VP8_STATUS_INVALID_PARAM; - goto Err; - } - - if (!AllocateInternalBuffers32b(dec, io->width)) goto Err; - - if (io->use_scaling && !AllocateAndInitRescaler(dec, io)) goto Err; - - if (io->use_scaling || WebPIsPremultipliedMode(dec->output_->colorspace)) { - // need the alpha-multiply functions for premultiplied output or rescaling - WebPInitAlphaProcessing(); - } - if (!WebPIsRGBMode(dec->output_->colorspace)) { - WebPInitConvertARGBToYUV(); - if (dec->output_->u.YUVA.a != NULL) WebPInitAlphaProcessing(); - } - if (dec->incremental_) { - if (dec->hdr_.color_cache_size_ > 0 && - dec->hdr_.saved_color_cache_.colors_ == NULL) { - if (!VP8LColorCacheInit(&dec->hdr_.saved_color_cache_, - dec->hdr_.color_cache_.hash_bits_)) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - goto Err; - } - } - } - dec->state_ = READ_DATA; - } - - // Decode. - if (!DecodeImageData(dec, dec->pixels_, dec->width_, dec->height_, - io->crop_bottom, ProcessRows)) { - goto Err; - } - - params->last_y = dec->last_out_row_; - return 1; - - Err: - VP8LClear(dec); - assert(dec->status_ != VP8_STATUS_OK); - return 0; -} - -//------------------------------------------------------------------------------ |