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Diffstat (limited to 'drivers/webp/enc/vp8l.c')
| -rw-r--r-- | drivers/webp/enc/vp8l.c | 1603 |
1 files changed, 0 insertions, 1603 deletions
diff --git a/drivers/webp/enc/vp8l.c b/drivers/webp/enc/vp8l.c deleted file mode 100644 index 1f2d41ea91..0000000000 --- a/drivers/webp/enc/vp8l.c +++ /dev/null @@ -1,1603 +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 lossless encoder. -// -// Author: Vikas Arora (vikaas.arora@gmail.com) -// - -#include <assert.h> -#include <stdlib.h> - -#include "./backward_references.h" -#include "./histogram.h" -#include "./vp8enci.h" -#include "./vp8li.h" -#include "../dsp/lossless.h" -#include "../utils/bit_writer.h" -#include "../utils/huffman_encode.h" -#include "../utils/utils.h" -#include "webp/format_constants.h" - -#include "./delta_palettization.h" - -#define PALETTE_KEY_RIGHT_SHIFT 22 // Key for 1K buffer. -// Maximum number of histogram images (sub-blocks). -#define MAX_HUFF_IMAGE_SIZE 2600 - -// Palette reordering for smaller sum of deltas (and for smaller storage). - -static int PaletteCompareColorsForQsort(const void* p1, const void* p2) { - const uint32_t a = WebPMemToUint32(p1); - const uint32_t b = WebPMemToUint32(p2); - assert(a != b); - return (a < b) ? -1 : 1; -} - -static WEBP_INLINE uint32_t PaletteComponentDistance(uint32_t v) { - return (v <= 128) ? v : (256 - v); -} - -// Computes a value that is related to the entropy created by the -// palette entry diff. -// -// Note that the last & 0xff is a no-operation in the next statement, but -// removed by most compilers and is here only for regularity of the code. -static WEBP_INLINE uint32_t PaletteColorDistance(uint32_t col1, uint32_t col2) { - const uint32_t diff = VP8LSubPixels(col1, col2); - const int kMoreWeightForRGBThanForAlpha = 9; - uint32_t score; - score = PaletteComponentDistance((diff >> 0) & 0xff); - score += PaletteComponentDistance((diff >> 8) & 0xff); - score += PaletteComponentDistance((diff >> 16) & 0xff); - score *= kMoreWeightForRGBThanForAlpha; - score += PaletteComponentDistance((diff >> 24) & 0xff); - return score; -} - -static WEBP_INLINE void SwapColor(uint32_t* const col1, uint32_t* const col2) { - const uint32_t tmp = *col1; - *col1 = *col2; - *col2 = tmp; -} - -static void GreedyMinimizeDeltas(uint32_t palette[], int num_colors) { - // Find greedily always the closest color of the predicted color to minimize - // deltas in the palette. This reduces storage needs since the - // palette is stored with delta encoding. - uint32_t predict = 0x00000000; - int i, k; - for (i = 0; i < num_colors; ++i) { - int best_ix = i; - uint32_t best_score = ~0U; - for (k = i; k < num_colors; ++k) { - const uint32_t cur_score = PaletteColorDistance(palette[k], predict); - if (best_score > cur_score) { - best_score = cur_score; - best_ix = k; - } - } - SwapColor(&palette[best_ix], &palette[i]); - predict = palette[i]; - } -} - -// The palette has been sorted by alpha. This function checks if the other -// components of the palette have a monotonic development with regards to -// position in the palette. If all have monotonic development, there is -// no benefit to re-organize them greedily. A monotonic development -// would be spotted in green-only situations (like lossy alpha) or gray-scale -// images. -static int PaletteHasNonMonotonousDeltas(uint32_t palette[], int num_colors) { - uint32_t predict = 0x000000; - int i; - uint8_t sign_found = 0x00; - for (i = 0; i < num_colors; ++i) { - const uint32_t diff = VP8LSubPixels(palette[i], predict); - const uint8_t rd = (diff >> 16) & 0xff; - const uint8_t gd = (diff >> 8) & 0xff; - const uint8_t bd = (diff >> 0) & 0xff; - if (rd != 0x00) { - sign_found |= (rd < 0x80) ? 1 : 2; - } - if (gd != 0x00) { - sign_found |= (gd < 0x80) ? 8 : 16; - } - if (bd != 0x00) { - sign_found |= (bd < 0x80) ? 64 : 128; - } - predict = palette[i]; - } - return (sign_found & (sign_found << 1)) != 0; // two consequent signs. -} - -// ----------------------------------------------------------------------------- -// Palette - -// If number of colors in the image is less than or equal to MAX_PALETTE_SIZE, -// creates a palette and returns true, else returns false. -static int AnalyzeAndCreatePalette(const WebPPicture* const pic, - int low_effort, - uint32_t palette[MAX_PALETTE_SIZE], - int* const palette_size) { - const int num_colors = WebPGetColorPalette(pic, palette); - if (num_colors > MAX_PALETTE_SIZE) return 0; - *palette_size = num_colors; - qsort(palette, num_colors, sizeof(*palette), PaletteCompareColorsForQsort); - if (!low_effort && PaletteHasNonMonotonousDeltas(palette, num_colors)) { - GreedyMinimizeDeltas(palette, num_colors); - } - return 1; -} - -// These five modes are evaluated and their respective entropy is computed. -typedef enum { - kDirect = 0, - kSpatial = 1, - kSubGreen = 2, - kSpatialSubGreen = 3, - kPalette = 4, - kNumEntropyIx = 5 -} EntropyIx; - -typedef enum { - kHistoAlpha = 0, - kHistoAlphaPred, - kHistoGreen, - kHistoGreenPred, - kHistoRed, - kHistoRedPred, - kHistoBlue, - kHistoBluePred, - kHistoRedSubGreen, - kHistoRedPredSubGreen, - kHistoBlueSubGreen, - kHistoBluePredSubGreen, - kHistoPalette, - kHistoTotal // Must be last. -} HistoIx; - -static void AddSingleSubGreen(uint32_t p, uint32_t* r, uint32_t* b) { - const uint32_t green = p >> 8; // The upper bits are masked away later. - ++r[((p >> 16) - green) & 0xff]; - ++b[(p - green) & 0xff]; -} - -static void AddSingle(uint32_t p, - uint32_t* a, uint32_t* r, uint32_t* g, uint32_t* b) { - ++a[p >> 24]; - ++r[(p >> 16) & 0xff]; - ++g[(p >> 8) & 0xff]; - ++b[(p & 0xff)]; -} - -static int AnalyzeEntropy(const uint32_t* argb, - int width, int height, int argb_stride, - int use_palette, - EntropyIx* const min_entropy_ix, - int* const red_and_blue_always_zero) { - // Allocate histogram set with cache_bits = 0. - uint32_t* const histo = - (uint32_t*)WebPSafeCalloc(kHistoTotal, sizeof(*histo) * 256); - if (histo != NULL) { - int i, x, y; - const uint32_t* prev_row = argb; - const uint32_t* curr_row = argb + argb_stride; - for (y = 1; y < height; ++y) { - uint32_t prev_pix = curr_row[0]; - for (x = 1; x < width; ++x) { - const uint32_t pix = curr_row[x]; - const uint32_t pix_diff = VP8LSubPixels(pix, prev_pix); - if ((pix_diff == 0) || (pix == prev_row[x])) continue; - prev_pix = pix; - AddSingle(pix, - &histo[kHistoAlpha * 256], - &histo[kHistoRed * 256], - &histo[kHistoGreen * 256], - &histo[kHistoBlue * 256]); - AddSingle(pix_diff, - &histo[kHistoAlphaPred * 256], - &histo[kHistoRedPred * 256], - &histo[kHistoGreenPred * 256], - &histo[kHistoBluePred * 256]); - AddSingleSubGreen(pix, - &histo[kHistoRedSubGreen * 256], - &histo[kHistoBlueSubGreen * 256]); - AddSingleSubGreen(pix_diff, - &histo[kHistoRedPredSubGreen * 256], - &histo[kHistoBluePredSubGreen * 256]); - { - // Approximate the palette by the entropy of the multiplicative hash. - const int hash = ((pix + (pix >> 19)) * 0x39c5fba7) >> 24; - ++histo[kHistoPalette * 256 + (hash & 0xff)]; - } - } - prev_row = curr_row; - curr_row += argb_stride; - } - { - double entropy_comp[kHistoTotal]; - double entropy[kNumEntropyIx]; - EntropyIx k; - EntropyIx last_mode_to_analyze = - use_palette ? kPalette : kSpatialSubGreen; - int j; - // Let's add one zero to the predicted histograms. The zeros are removed - // too efficiently by the pix_diff == 0 comparison, at least one of the - // zeros is likely to exist. - ++histo[kHistoRedPredSubGreen * 256]; - ++histo[kHistoBluePredSubGreen * 256]; - ++histo[kHistoRedPred * 256]; - ++histo[kHistoGreenPred * 256]; - ++histo[kHistoBluePred * 256]; - ++histo[kHistoAlphaPred * 256]; - - for (j = 0; j < kHistoTotal; ++j) { - entropy_comp[j] = VP8LBitsEntropy(&histo[j * 256], 256, NULL); - } - entropy[kDirect] = entropy_comp[kHistoAlpha] + - entropy_comp[kHistoRed] + - entropy_comp[kHistoGreen] + - entropy_comp[kHistoBlue]; - entropy[kSpatial] = entropy_comp[kHistoAlphaPred] + - entropy_comp[kHistoRedPred] + - entropy_comp[kHistoGreenPred] + - entropy_comp[kHistoBluePred]; - entropy[kSubGreen] = entropy_comp[kHistoAlpha] + - entropy_comp[kHistoRedSubGreen] + - entropy_comp[kHistoGreen] + - entropy_comp[kHistoBlueSubGreen]; - entropy[kSpatialSubGreen] = entropy_comp[kHistoAlphaPred] + - entropy_comp[kHistoRedPredSubGreen] + - entropy_comp[kHistoGreenPred] + - entropy_comp[kHistoBluePredSubGreen]; - // Palette mode seems more efficient in a breakeven case. Bias with 1.0. - entropy[kPalette] = entropy_comp[kHistoPalette] - 1.0; - - *min_entropy_ix = kDirect; - for (k = kDirect + 1; k <= last_mode_to_analyze; ++k) { - if (entropy[*min_entropy_ix] > entropy[k]) { - *min_entropy_ix = k; - } - } - *red_and_blue_always_zero = 1; - // Let's check if the histogram of the chosen entropy mode has - // non-zero red and blue values. If all are zero, we can later skip - // the cross color optimization. - { - static const uint8_t kHistoPairs[5][2] = { - { kHistoRed, kHistoBlue }, - { kHistoRedPred, kHistoBluePred }, - { kHistoRedSubGreen, kHistoBlueSubGreen }, - { kHistoRedPredSubGreen, kHistoBluePredSubGreen }, - { kHistoRed, kHistoBlue } - }; - const uint32_t* const red_histo = - &histo[256 * kHistoPairs[*min_entropy_ix][0]]; - const uint32_t* const blue_histo = - &histo[256 * kHistoPairs[*min_entropy_ix][1]]; - for (i = 1; i < 256; ++i) { - if ((red_histo[i] | blue_histo[i]) != 0) { - *red_and_blue_always_zero = 0; - break; - } - } - } - } - WebPSafeFree(histo); - return 1; - } else { - return 0; - } -} - -static int GetHistoBits(int method, int use_palette, int width, int height) { - // Make tile size a function of encoding method (Range: 0 to 6). - int histo_bits = (use_palette ? 9 : 7) - method; - while (1) { - const int huff_image_size = VP8LSubSampleSize(width, histo_bits) * - VP8LSubSampleSize(height, histo_bits); - if (huff_image_size <= MAX_HUFF_IMAGE_SIZE) break; - ++histo_bits; - } - return (histo_bits < MIN_HUFFMAN_BITS) ? MIN_HUFFMAN_BITS : - (histo_bits > MAX_HUFFMAN_BITS) ? MAX_HUFFMAN_BITS : histo_bits; -} - -static int GetTransformBits(int method, int histo_bits) { - const int max_transform_bits = (method < 4) ? 6 : (method > 4) ? 4 : 5; - return (histo_bits > max_transform_bits) ? max_transform_bits : histo_bits; -} - -static int AnalyzeAndInit(VP8LEncoder* const enc) { - const WebPPicture* const pic = enc->pic_; - const int width = pic->width; - const int height = pic->height; - const int pix_cnt = width * height; - const WebPConfig* const config = enc->config_; - const int method = config->method; - const int low_effort = (config->method == 0); - // we round the block size up, so we're guaranteed to have - // at max MAX_REFS_BLOCK_PER_IMAGE blocks used: - int refs_block_size = (pix_cnt - 1) / MAX_REFS_BLOCK_PER_IMAGE + 1; - assert(pic != NULL && pic->argb != NULL); - - enc->use_cross_color_ = 0; - enc->use_predict_ = 0; - enc->use_subtract_green_ = 0; - enc->use_palette_ = - AnalyzeAndCreatePalette(pic, low_effort, - enc->palette_, &enc->palette_size_); - - // TODO(jyrki): replace the decision to be based on an actual estimate - // of entropy, or even spatial variance of entropy. - enc->histo_bits_ = GetHistoBits(method, enc->use_palette_, - pic->width, pic->height); - enc->transform_bits_ = GetTransformBits(method, enc->histo_bits_); - - if (low_effort) { - // AnalyzeEntropy is somewhat slow. - enc->use_predict_ = !enc->use_palette_; - enc->use_subtract_green_ = !enc->use_palette_; - enc->use_cross_color_ = 0; - } else { - int red_and_blue_always_zero; - EntropyIx min_entropy_ix; - if (!AnalyzeEntropy(pic->argb, width, height, pic->argb_stride, - enc->use_palette_, &min_entropy_ix, - &red_and_blue_always_zero)) { - return 0; - } - enc->use_palette_ = (min_entropy_ix == kPalette); - enc->use_subtract_green_ = - (min_entropy_ix == kSubGreen) || (min_entropy_ix == kSpatialSubGreen); - enc->use_predict_ = - (min_entropy_ix == kSpatial) || (min_entropy_ix == kSpatialSubGreen); - enc->use_cross_color_ = red_and_blue_always_zero ? 0 : enc->use_predict_; - } - - if (!VP8LHashChainInit(&enc->hash_chain_, pix_cnt)) return 0; - - // palette-friendly input typically uses less literals - // -> reduce block size a bit - if (enc->use_palette_) refs_block_size /= 2; - VP8LBackwardRefsInit(&enc->refs_[0], refs_block_size); - VP8LBackwardRefsInit(&enc->refs_[1], refs_block_size); - - return 1; -} - -// Returns false in case of memory error. -static int GetHuffBitLengthsAndCodes( - const VP8LHistogramSet* const histogram_image, - HuffmanTreeCode* const huffman_codes) { - int i, k; - int ok = 0; - uint64_t total_length_size = 0; - uint8_t* mem_buf = NULL; - const int histogram_image_size = histogram_image->size; - int max_num_symbols = 0; - uint8_t* buf_rle = NULL; - HuffmanTree* huff_tree = NULL; - - // Iterate over all histograms and get the aggregate number of codes used. - for (i = 0; i < histogram_image_size; ++i) { - const VP8LHistogram* const histo = histogram_image->histograms[i]; - HuffmanTreeCode* const codes = &huffman_codes[5 * i]; - for (k = 0; k < 5; ++k) { - const int num_symbols = - (k == 0) ? VP8LHistogramNumCodes(histo->palette_code_bits_) : - (k == 4) ? NUM_DISTANCE_CODES : 256; - codes[k].num_symbols = num_symbols; - total_length_size += num_symbols; - } - } - - // Allocate and Set Huffman codes. - { - uint16_t* codes; - uint8_t* lengths; - mem_buf = (uint8_t*)WebPSafeCalloc(total_length_size, - sizeof(*lengths) + sizeof(*codes)); - if (mem_buf == NULL) goto End; - - codes = (uint16_t*)mem_buf; - lengths = (uint8_t*)&codes[total_length_size]; - for (i = 0; i < 5 * histogram_image_size; ++i) { - const int bit_length = huffman_codes[i].num_symbols; - huffman_codes[i].codes = codes; - huffman_codes[i].code_lengths = lengths; - codes += bit_length; - lengths += bit_length; - if (max_num_symbols < bit_length) { - max_num_symbols = bit_length; - } - } - } - - buf_rle = (uint8_t*)WebPSafeMalloc(1ULL, max_num_symbols); - huff_tree = (HuffmanTree*)WebPSafeMalloc(3ULL * max_num_symbols, - sizeof(*huff_tree)); - if (buf_rle == NULL || huff_tree == NULL) goto End; - - // Create Huffman trees. - for (i = 0; i < histogram_image_size; ++i) { - HuffmanTreeCode* const codes = &huffman_codes[5 * i]; - VP8LHistogram* const histo = histogram_image->histograms[i]; - VP8LCreateHuffmanTree(histo->literal_, 15, buf_rle, huff_tree, codes + 0); - VP8LCreateHuffmanTree(histo->red_, 15, buf_rle, huff_tree, codes + 1); - VP8LCreateHuffmanTree(histo->blue_, 15, buf_rle, huff_tree, codes + 2); - VP8LCreateHuffmanTree(histo->alpha_, 15, buf_rle, huff_tree, codes + 3); - VP8LCreateHuffmanTree(histo->distance_, 15, buf_rle, huff_tree, codes + 4); - } - ok = 1; - End: - WebPSafeFree(huff_tree); - WebPSafeFree(buf_rle); - if (!ok) { - WebPSafeFree(mem_buf); - memset(huffman_codes, 0, 5 * histogram_image_size * sizeof(*huffman_codes)); - } - return ok; -} - -static void StoreHuffmanTreeOfHuffmanTreeToBitMask( - VP8LBitWriter* const bw, const uint8_t* code_length_bitdepth) { - // RFC 1951 will calm you down if you are worried about this funny sequence. - // This sequence is tuned from that, but more weighted for lower symbol count, - // and more spiking histograms. - static const uint8_t kStorageOrder[CODE_LENGTH_CODES] = { - 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 - }; - int i; - // Throw away trailing zeros: - int codes_to_store = CODE_LENGTH_CODES; - for (; codes_to_store > 4; --codes_to_store) { - if (code_length_bitdepth[kStorageOrder[codes_to_store - 1]] != 0) { - break; - } - } - VP8LPutBits(bw, codes_to_store - 4, 4); - for (i = 0; i < codes_to_store; ++i) { - VP8LPutBits(bw, code_length_bitdepth[kStorageOrder[i]], 3); - } -} - -static void ClearHuffmanTreeIfOnlyOneSymbol( - HuffmanTreeCode* const huffman_code) { - int k; - int count = 0; - for (k = 0; k < huffman_code->num_symbols; ++k) { - if (huffman_code->code_lengths[k] != 0) { - ++count; - if (count > 1) return; - } - } - for (k = 0; k < huffman_code->num_symbols; ++k) { - huffman_code->code_lengths[k] = 0; - huffman_code->codes[k] = 0; - } -} - -static void StoreHuffmanTreeToBitMask( - VP8LBitWriter* const bw, - const HuffmanTreeToken* const tokens, const int num_tokens, - const HuffmanTreeCode* const huffman_code) { - int i; - for (i = 0; i < num_tokens; ++i) { - const int ix = tokens[i].code; - const int extra_bits = tokens[i].extra_bits; - VP8LPutBits(bw, huffman_code->codes[ix], huffman_code->code_lengths[ix]); - switch (ix) { - case 16: - VP8LPutBits(bw, extra_bits, 2); - break; - case 17: - VP8LPutBits(bw, extra_bits, 3); - break; - case 18: - VP8LPutBits(bw, extra_bits, 7); - break; - } - } -} - -// 'huff_tree' and 'tokens' are pre-alloacted buffers. -static void StoreFullHuffmanCode(VP8LBitWriter* const bw, - HuffmanTree* const huff_tree, - HuffmanTreeToken* const tokens, - const HuffmanTreeCode* const tree) { - uint8_t code_length_bitdepth[CODE_LENGTH_CODES] = { 0 }; - uint16_t code_length_bitdepth_symbols[CODE_LENGTH_CODES] = { 0 }; - const int max_tokens = tree->num_symbols; - int num_tokens; - HuffmanTreeCode huffman_code; - huffman_code.num_symbols = CODE_LENGTH_CODES; - huffman_code.code_lengths = code_length_bitdepth; - huffman_code.codes = code_length_bitdepth_symbols; - - VP8LPutBits(bw, 0, 1); - num_tokens = VP8LCreateCompressedHuffmanTree(tree, tokens, max_tokens); - { - uint32_t histogram[CODE_LENGTH_CODES] = { 0 }; - uint8_t buf_rle[CODE_LENGTH_CODES] = { 0 }; - int i; - for (i = 0; i < num_tokens; ++i) { - ++histogram[tokens[i].code]; - } - - VP8LCreateHuffmanTree(histogram, 7, buf_rle, huff_tree, &huffman_code); - } - - StoreHuffmanTreeOfHuffmanTreeToBitMask(bw, code_length_bitdepth); - ClearHuffmanTreeIfOnlyOneSymbol(&huffman_code); - { - int trailing_zero_bits = 0; - int trimmed_length = num_tokens; - int write_trimmed_length; - int length; - int i = num_tokens; - while (i-- > 0) { - const int ix = tokens[i].code; - if (ix == 0 || ix == 17 || ix == 18) { - --trimmed_length; // discount trailing zeros - trailing_zero_bits += code_length_bitdepth[ix]; - if (ix == 17) { - trailing_zero_bits += 3; - } else if (ix == 18) { - trailing_zero_bits += 7; - } - } else { - break; - } - } - write_trimmed_length = (trimmed_length > 1 && trailing_zero_bits > 12); - length = write_trimmed_length ? trimmed_length : num_tokens; - VP8LPutBits(bw, write_trimmed_length, 1); - if (write_trimmed_length) { - const int nbits = VP8LBitsLog2Ceiling(trimmed_length - 1); - const int nbitpairs = (nbits == 0) ? 1 : (nbits + 1) / 2; - VP8LPutBits(bw, nbitpairs - 1, 3); - assert(trimmed_length >= 2); - VP8LPutBits(bw, trimmed_length - 2, nbitpairs * 2); - } - StoreHuffmanTreeToBitMask(bw, tokens, length, &huffman_code); - } -} - -// 'huff_tree' and 'tokens' are pre-alloacted buffers. -static void StoreHuffmanCode(VP8LBitWriter* const bw, - HuffmanTree* const huff_tree, - HuffmanTreeToken* const tokens, - const HuffmanTreeCode* const huffman_code) { - int i; - int count = 0; - int symbols[2] = { 0, 0 }; - const int kMaxBits = 8; - const int kMaxSymbol = 1 << kMaxBits; - - // Check whether it's a small tree. - for (i = 0; i < huffman_code->num_symbols && count < 3; ++i) { - if (huffman_code->code_lengths[i] != 0) { - if (count < 2) symbols[count] = i; - ++count; - } - } - - if (count == 0) { // emit minimal tree for empty cases - // bits: small tree marker: 1, count-1: 0, large 8-bit code: 0, code: 0 - VP8LPutBits(bw, 0x01, 4); - } else if (count <= 2 && symbols[0] < kMaxSymbol && symbols[1] < kMaxSymbol) { - VP8LPutBits(bw, 1, 1); // Small tree marker to encode 1 or 2 symbols. - VP8LPutBits(bw, count - 1, 1); - if (symbols[0] <= 1) { - VP8LPutBits(bw, 0, 1); // Code bit for small (1 bit) symbol value. - VP8LPutBits(bw, symbols[0], 1); - } else { - VP8LPutBits(bw, 1, 1); - VP8LPutBits(bw, symbols[0], 8); - } - if (count == 2) { - VP8LPutBits(bw, symbols[1], 8); - } - } else { - StoreFullHuffmanCode(bw, huff_tree, tokens, huffman_code); - } -} - -static WEBP_INLINE void WriteHuffmanCode(VP8LBitWriter* const bw, - const HuffmanTreeCode* const code, - int code_index) { - const int depth = code->code_lengths[code_index]; - const int symbol = code->codes[code_index]; - VP8LPutBits(bw, symbol, depth); -} - -static WEBP_INLINE void WriteHuffmanCodeWithExtraBits( - VP8LBitWriter* const bw, - const HuffmanTreeCode* const code, - int code_index, - int bits, - int n_bits) { - const int depth = code->code_lengths[code_index]; - const int symbol = code->codes[code_index]; - VP8LPutBits(bw, (bits << depth) | symbol, depth + n_bits); -} - -static WebPEncodingError StoreImageToBitMask( - VP8LBitWriter* const bw, int width, int histo_bits, - VP8LBackwardRefs* const refs, - const uint16_t* histogram_symbols, - const HuffmanTreeCode* const huffman_codes) { - const int histo_xsize = histo_bits ? VP8LSubSampleSize(width, histo_bits) : 1; - const int tile_mask = (histo_bits == 0) ? 0 : -(1 << histo_bits); - // x and y trace the position in the image. - int x = 0; - int y = 0; - int tile_x = x & tile_mask; - int tile_y = y & tile_mask; - int histogram_ix = histogram_symbols[0]; - const HuffmanTreeCode* codes = huffman_codes + 5 * histogram_ix; - VP8LRefsCursor c = VP8LRefsCursorInit(refs); - while (VP8LRefsCursorOk(&c)) { - const PixOrCopy* const v = c.cur_pos; - if ((tile_x != (x & tile_mask)) || (tile_y != (y & tile_mask))) { - tile_x = x & tile_mask; - tile_y = y & tile_mask; - histogram_ix = histogram_symbols[(y >> histo_bits) * histo_xsize + - (x >> histo_bits)]; - codes = huffman_codes + 5 * histogram_ix; - } - if (PixOrCopyIsLiteral(v)) { - static const int order[] = { 1, 2, 0, 3 }; - int k; - for (k = 0; k < 4; ++k) { - const int code = PixOrCopyLiteral(v, order[k]); - WriteHuffmanCode(bw, codes + k, code); - } - } else if (PixOrCopyIsCacheIdx(v)) { - const int code = PixOrCopyCacheIdx(v); - const int literal_ix = 256 + NUM_LENGTH_CODES + code; - WriteHuffmanCode(bw, codes, literal_ix); - } else { - int bits, n_bits; - int code; - - const int distance = PixOrCopyDistance(v); - VP8LPrefixEncode(v->len, &code, &n_bits, &bits); - WriteHuffmanCodeWithExtraBits(bw, codes, 256 + code, bits, n_bits); - - // Don't write the distance with the extra bits code since - // the distance can be up to 18 bits of extra bits, and the prefix - // 15 bits, totaling to 33, and our PutBits only supports up to 32 bits. - // TODO(jyrki): optimize this further. - VP8LPrefixEncode(distance, &code, &n_bits, &bits); - WriteHuffmanCode(bw, codes + 4, code); - VP8LPutBits(bw, bits, n_bits); - } - x += PixOrCopyLength(v); - while (x >= width) { - x -= width; - ++y; - } - VP8LRefsCursorNext(&c); - } - return bw->error_ ? VP8_ENC_ERROR_OUT_OF_MEMORY : VP8_ENC_OK; -} - -// Special case of EncodeImageInternal() for cache-bits=0, histo_bits=31 -static WebPEncodingError EncodeImageNoHuffman(VP8LBitWriter* const bw, - const uint32_t* const argb, - VP8LHashChain* const hash_chain, - VP8LBackwardRefs refs_array[2], - int width, int height, - int quality) { - int i; - int max_tokens = 0; - WebPEncodingError err = VP8_ENC_OK; - VP8LBackwardRefs* refs; - HuffmanTreeToken* tokens = NULL; - HuffmanTreeCode huffman_codes[5] = { { 0, NULL, NULL } }; - const uint16_t histogram_symbols[1] = { 0 }; // only one tree, one symbol - int cache_bits = 0; - VP8LHistogramSet* histogram_image = NULL; - HuffmanTree* const huff_tree = (HuffmanTree*)WebPSafeMalloc( - 3ULL * CODE_LENGTH_CODES, sizeof(*huff_tree)); - if (huff_tree == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // Calculate backward references from ARGB image. - if (VP8LHashChainFill(hash_chain, quality, argb, width, height) == 0) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - refs = VP8LGetBackwardReferences(width, height, argb, quality, 0, &cache_bits, - hash_chain, refs_array); - if (refs == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - histogram_image = VP8LAllocateHistogramSet(1, cache_bits); - if (histogram_image == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // Build histogram image and symbols from backward references. - VP8LHistogramStoreRefs(refs, histogram_image->histograms[0]); - - // Create Huffman bit lengths and codes for each histogram image. - assert(histogram_image->size == 1); - if (!GetHuffBitLengthsAndCodes(histogram_image, huffman_codes)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // No color cache, no Huffman image. - VP8LPutBits(bw, 0, 1); - - // Find maximum number of symbols for the huffman tree-set. - for (i = 0; i < 5; ++i) { - HuffmanTreeCode* const codes = &huffman_codes[i]; - if (max_tokens < codes->num_symbols) { - max_tokens = codes->num_symbols; - } - } - - tokens = (HuffmanTreeToken*)WebPSafeMalloc(max_tokens, sizeof(*tokens)); - if (tokens == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // Store Huffman codes. - for (i = 0; i < 5; ++i) { - HuffmanTreeCode* const codes = &huffman_codes[i]; - StoreHuffmanCode(bw, huff_tree, tokens, codes); - ClearHuffmanTreeIfOnlyOneSymbol(codes); - } - - // Store actual literals. - err = StoreImageToBitMask(bw, width, 0, refs, histogram_symbols, - huffman_codes); - - Error: - WebPSafeFree(tokens); - WebPSafeFree(huff_tree); - VP8LFreeHistogramSet(histogram_image); - WebPSafeFree(huffman_codes[0].codes); - return err; -} - -static WebPEncodingError EncodeImageInternal(VP8LBitWriter* const bw, - const uint32_t* const argb, - VP8LHashChain* const hash_chain, - VP8LBackwardRefs refs_array[2], - int width, int height, int quality, - int low_effort, - int use_cache, int* cache_bits, - int histogram_bits, - size_t init_byte_position, - int* const hdr_size, - int* const data_size) { - WebPEncodingError err = VP8_ENC_OK; - const uint32_t histogram_image_xysize = - VP8LSubSampleSize(width, histogram_bits) * - VP8LSubSampleSize(height, histogram_bits); - VP8LHistogramSet* histogram_image = NULL; - VP8LHistogramSet* tmp_histos = NULL; - int histogram_image_size = 0; - size_t bit_array_size = 0; - HuffmanTree* huff_tree = NULL; - HuffmanTreeToken* tokens = NULL; - HuffmanTreeCode* huffman_codes = NULL; - VP8LBackwardRefs refs; - VP8LBackwardRefs* best_refs; - uint16_t* const histogram_symbols = - (uint16_t*)WebPSafeMalloc(histogram_image_xysize, - sizeof(*histogram_symbols)); - assert(histogram_bits >= MIN_HUFFMAN_BITS); - assert(histogram_bits <= MAX_HUFFMAN_BITS); - assert(hdr_size != NULL); - assert(data_size != NULL); - - VP8LBackwardRefsInit(&refs, refs_array[0].block_size_); - if (histogram_symbols == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - *cache_bits = use_cache ? MAX_COLOR_CACHE_BITS : 0; - // 'best_refs' is the reference to the best backward refs and points to one - // of refs_array[0] or refs_array[1]. - // Calculate backward references from ARGB image. - if (VP8LHashChainFill(hash_chain, quality, argb, width, height) == 0) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - best_refs = VP8LGetBackwardReferences(width, height, argb, quality, - low_effort, cache_bits, hash_chain, - refs_array); - if (best_refs == NULL || !VP8LBackwardRefsCopy(best_refs, &refs)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - histogram_image = - VP8LAllocateHistogramSet(histogram_image_xysize, *cache_bits); - tmp_histos = VP8LAllocateHistogramSet(2, *cache_bits); - if (histogram_image == NULL || tmp_histos == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // Build histogram image and symbols from backward references. - if (!VP8LGetHistoImageSymbols(width, height, &refs, quality, low_effort, - histogram_bits, *cache_bits, histogram_image, - tmp_histos, histogram_symbols)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - // Create Huffman bit lengths and codes for each histogram image. - histogram_image_size = histogram_image->size; - bit_array_size = 5 * histogram_image_size; - huffman_codes = (HuffmanTreeCode*)WebPSafeCalloc(bit_array_size, - sizeof(*huffman_codes)); - // Note: some histogram_image entries may point to tmp_histos[], so the latter - // need to outlive the following call to GetHuffBitLengthsAndCodes(). - if (huffman_codes == NULL || - !GetHuffBitLengthsAndCodes(histogram_image, huffman_codes)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - // Free combined histograms. - VP8LFreeHistogramSet(histogram_image); - histogram_image = NULL; - - // Free scratch histograms. - VP8LFreeHistogramSet(tmp_histos); - tmp_histos = NULL; - - // Color Cache parameters. - if (*cache_bits > 0) { - VP8LPutBits(bw, 1, 1); - VP8LPutBits(bw, *cache_bits, 4); - } else { - VP8LPutBits(bw, 0, 1); - } - - // Huffman image + meta huffman. - { - const int write_histogram_image = (histogram_image_size > 1); - VP8LPutBits(bw, write_histogram_image, 1); - if (write_histogram_image) { - uint32_t* const histogram_argb = - (uint32_t*)WebPSafeMalloc(histogram_image_xysize, - sizeof(*histogram_argb)); - int max_index = 0; - uint32_t i; - if (histogram_argb == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - for (i = 0; i < histogram_image_xysize; ++i) { - const int symbol_index = histogram_symbols[i] & 0xffff; - histogram_argb[i] = (symbol_index << 8); - if (symbol_index >= max_index) { - max_index = symbol_index + 1; - } - } - histogram_image_size = max_index; - - VP8LPutBits(bw, histogram_bits - 2, 3); - err = EncodeImageNoHuffman(bw, histogram_argb, hash_chain, refs_array, - VP8LSubSampleSize(width, histogram_bits), - VP8LSubSampleSize(height, histogram_bits), - quality); - WebPSafeFree(histogram_argb); - if (err != VP8_ENC_OK) goto Error; - } - } - - // Store Huffman codes. - { - int i; - int max_tokens = 0; - huff_tree = (HuffmanTree*)WebPSafeMalloc(3ULL * CODE_LENGTH_CODES, - sizeof(*huff_tree)); - if (huff_tree == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - // Find maximum number of symbols for the huffman tree-set. - for (i = 0; i < 5 * histogram_image_size; ++i) { - HuffmanTreeCode* const codes = &huffman_codes[i]; - if (max_tokens < codes->num_symbols) { - max_tokens = codes->num_symbols; - } - } - tokens = (HuffmanTreeToken*)WebPSafeMalloc(max_tokens, - sizeof(*tokens)); - if (tokens == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - for (i = 0; i < 5 * histogram_image_size; ++i) { - HuffmanTreeCode* const codes = &huffman_codes[i]; - StoreHuffmanCode(bw, huff_tree, tokens, codes); - ClearHuffmanTreeIfOnlyOneSymbol(codes); - } - } - - *hdr_size = (int)(VP8LBitWriterNumBytes(bw) - init_byte_position); - // Store actual literals. - err = StoreImageToBitMask(bw, width, histogram_bits, &refs, - histogram_symbols, huffman_codes); - *data_size = - (int)(VP8LBitWriterNumBytes(bw) - init_byte_position - *hdr_size); - - Error: - WebPSafeFree(tokens); - WebPSafeFree(huff_tree); - VP8LFreeHistogramSet(histogram_image); - VP8LFreeHistogramSet(tmp_histos); - VP8LBackwardRefsClear(&refs); - if (huffman_codes != NULL) { - WebPSafeFree(huffman_codes->codes); - WebPSafeFree(huffman_codes); - } - WebPSafeFree(histogram_symbols); - return err; -} - -// ----------------------------------------------------------------------------- -// Transforms - -static void ApplySubtractGreen(VP8LEncoder* const enc, int width, int height, - VP8LBitWriter* const bw) { - VP8LPutBits(bw, TRANSFORM_PRESENT, 1); - VP8LPutBits(bw, SUBTRACT_GREEN, 2); - VP8LSubtractGreenFromBlueAndRed(enc->argb_, width * height); -} - -static WebPEncodingError ApplyPredictFilter(const VP8LEncoder* const enc, - int width, int height, - int quality, int low_effort, - int used_subtract_green, - VP8LBitWriter* const bw) { - const int pred_bits = enc->transform_bits_; - const int transform_width = VP8LSubSampleSize(width, pred_bits); - const int transform_height = VP8LSubSampleSize(height, pred_bits); - // we disable near-lossless quantization if palette is used. - const int near_lossless_strength = enc->use_palette_ ? 100 - : enc->config_->near_lossless; - - VP8LResidualImage(width, height, pred_bits, low_effort, enc->argb_, - enc->argb_scratch_, enc->transform_data_, - near_lossless_strength, enc->config_->exact, - used_subtract_green); - VP8LPutBits(bw, TRANSFORM_PRESENT, 1); - VP8LPutBits(bw, PREDICTOR_TRANSFORM, 2); - assert(pred_bits >= 2); - VP8LPutBits(bw, pred_bits - 2, 3); - return EncodeImageNoHuffman(bw, enc->transform_data_, - (VP8LHashChain*)&enc->hash_chain_, - (VP8LBackwardRefs*)enc->refs_, // cast const away - transform_width, transform_height, - quality); -} - -static WebPEncodingError ApplyCrossColorFilter(const VP8LEncoder* const enc, - int width, int height, - int quality, - VP8LBitWriter* const bw) { - const int ccolor_transform_bits = enc->transform_bits_; - const int transform_width = VP8LSubSampleSize(width, ccolor_transform_bits); - const int transform_height = VP8LSubSampleSize(height, ccolor_transform_bits); - - VP8LColorSpaceTransform(width, height, ccolor_transform_bits, quality, - enc->argb_, enc->transform_data_); - VP8LPutBits(bw, TRANSFORM_PRESENT, 1); - VP8LPutBits(bw, CROSS_COLOR_TRANSFORM, 2); - assert(ccolor_transform_bits >= 2); - VP8LPutBits(bw, ccolor_transform_bits - 2, 3); - return EncodeImageNoHuffman(bw, enc->transform_data_, - (VP8LHashChain*)&enc->hash_chain_, - (VP8LBackwardRefs*)enc->refs_, // cast const away - transform_width, transform_height, - quality); -} - -// ----------------------------------------------------------------------------- - -static WebPEncodingError WriteRiffHeader(const WebPPicture* const pic, - size_t riff_size, size_t vp8l_size) { - uint8_t riff[RIFF_HEADER_SIZE + CHUNK_HEADER_SIZE + VP8L_SIGNATURE_SIZE] = { - 'R', 'I', 'F', 'F', 0, 0, 0, 0, 'W', 'E', 'B', 'P', - 'V', 'P', '8', 'L', 0, 0, 0, 0, VP8L_MAGIC_BYTE, - }; - PutLE32(riff + TAG_SIZE, (uint32_t)riff_size); - PutLE32(riff + RIFF_HEADER_SIZE + TAG_SIZE, (uint32_t)vp8l_size); - if (!pic->writer(riff, sizeof(riff), pic)) { - return VP8_ENC_ERROR_BAD_WRITE; - } - return VP8_ENC_OK; -} - -static int WriteImageSize(const WebPPicture* const pic, - VP8LBitWriter* const bw) { - const int width = pic->width - 1; - const int height = pic->height - 1; - assert(width < WEBP_MAX_DIMENSION && height < WEBP_MAX_DIMENSION); - - VP8LPutBits(bw, width, VP8L_IMAGE_SIZE_BITS); - VP8LPutBits(bw, height, VP8L_IMAGE_SIZE_BITS); - return !bw->error_; -} - -static int WriteRealAlphaAndVersion(VP8LBitWriter* const bw, int has_alpha) { - VP8LPutBits(bw, has_alpha, 1); - VP8LPutBits(bw, VP8L_VERSION, VP8L_VERSION_BITS); - return !bw->error_; -} - -static WebPEncodingError WriteImage(const WebPPicture* const pic, - VP8LBitWriter* const bw, - size_t* const coded_size) { - WebPEncodingError err = VP8_ENC_OK; - const uint8_t* const webpll_data = VP8LBitWriterFinish(bw); - const size_t webpll_size = VP8LBitWriterNumBytes(bw); - const size_t vp8l_size = VP8L_SIGNATURE_SIZE + webpll_size; - const size_t pad = vp8l_size & 1; - const size_t riff_size = TAG_SIZE + CHUNK_HEADER_SIZE + vp8l_size + pad; - - err = WriteRiffHeader(pic, riff_size, vp8l_size); - if (err != VP8_ENC_OK) goto Error; - - if (!pic->writer(webpll_data, webpll_size, pic)) { - err = VP8_ENC_ERROR_BAD_WRITE; - goto Error; - } - - if (pad) { - const uint8_t pad_byte[1] = { 0 }; - if (!pic->writer(pad_byte, 1, pic)) { - err = VP8_ENC_ERROR_BAD_WRITE; - goto Error; - } - } - *coded_size = CHUNK_HEADER_SIZE + riff_size; - return VP8_ENC_OK; - - Error: - return err; -} - -// ----------------------------------------------------------------------------- - -static void ClearTransformBuffer(VP8LEncoder* const enc) { - WebPSafeFree(enc->transform_mem_); - enc->transform_mem_ = NULL; - enc->transform_mem_size_ = 0; -} - -// Allocates the memory for argb (W x H) buffer, 2 rows of context for -// prediction and transform data. -// Flags influencing the memory allocated: -// enc->transform_bits_ -// enc->use_predict_, enc->use_cross_color_ -static WebPEncodingError AllocateTransformBuffer(VP8LEncoder* const enc, - int width, int height) { - WebPEncodingError err = VP8_ENC_OK; - const uint64_t image_size = width * height; - // VP8LResidualImage needs room for 2 scanlines of uint32 pixels with an extra - // pixel in each, plus 2 regular scanlines of bytes. - // TODO(skal): Clean up by using arithmetic in bytes instead of words. - const uint64_t argb_scratch_size = - enc->use_predict_ - ? (width + 1) * 2 + - (width * 2 + sizeof(uint32_t) - 1) / sizeof(uint32_t) - : 0; - const uint64_t transform_data_size = - (enc->use_predict_ || enc->use_cross_color_) - ? VP8LSubSampleSize(width, enc->transform_bits_) * - VP8LSubSampleSize(height, enc->transform_bits_) - : 0; - const uint64_t max_alignment_in_words = - (WEBP_ALIGN_CST + sizeof(uint32_t) - 1) / sizeof(uint32_t); - const uint64_t mem_size = - image_size + max_alignment_in_words + - argb_scratch_size + max_alignment_in_words + - transform_data_size; - uint32_t* mem = enc->transform_mem_; - if (mem == NULL || mem_size > enc->transform_mem_size_) { - ClearTransformBuffer(enc); - mem = (uint32_t*)WebPSafeMalloc(mem_size, sizeof(*mem)); - if (mem == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - enc->transform_mem_ = mem; - enc->transform_mem_size_ = (size_t)mem_size; - } - enc->argb_ = mem; - mem = (uint32_t*)WEBP_ALIGN(mem + image_size); - enc->argb_scratch_ = mem; - mem = (uint32_t*)WEBP_ALIGN(mem + argb_scratch_size); - enc->transform_data_ = mem; - - enc->current_width_ = width; - Error: - return err; -} - -static WebPEncodingError MakeInputImageCopy(VP8LEncoder* const enc) { - WebPEncodingError err = VP8_ENC_OK; - const WebPPicture* const picture = enc->pic_; - const int width = picture->width; - const int height = picture->height; - int y; - err = AllocateTransformBuffer(enc, width, height); - if (err != VP8_ENC_OK) return err; - for (y = 0; y < height; ++y) { - memcpy(enc->argb_ + y * width, - picture->argb + y * picture->argb_stride, - width * sizeof(*enc->argb_)); - } - assert(enc->current_width_ == width); - return VP8_ENC_OK; -} - -// ----------------------------------------------------------------------------- - -static int SearchColor(const uint32_t sorted[], uint32_t color, int hi) { - int low = 0; - if (sorted[low] == color) return low; // loop invariant: sorted[low] != color - while (1) { - const int mid = (low + hi) >> 1; - if (sorted[mid] == color) { - return mid; - } else if (sorted[mid] < color) { - low = mid; - } else { - hi = mid; - } - } -} - -// Sort palette in increasing order and prepare an inverse mapping array. -static void PrepareMapToPalette(const uint32_t palette[], int num_colors, - uint32_t sorted[], int idx_map[]) { - int i; - memcpy(sorted, palette, num_colors * sizeof(*sorted)); - qsort(sorted, num_colors, sizeof(*sorted), PaletteCompareColorsForQsort); - for (i = 0; i < num_colors; ++i) { - idx_map[SearchColor(sorted, palette[i], num_colors)] = i; - } -} - -static void MapToPalette(const uint32_t sorted_palette[], int num_colors, - uint32_t* const last_pix, int* const last_idx, - const int idx_map[], - const uint32_t* src, uint8_t* dst, int width) { - int x; - int prev_idx = *last_idx; - uint32_t prev_pix = *last_pix; - for (x = 0; x < width; ++x) { - const uint32_t pix = src[x]; - if (pix != prev_pix) { - prev_idx = idx_map[SearchColor(sorted_palette, pix, num_colors)]; - prev_pix = pix; - } - dst[x] = prev_idx; - } - *last_idx = prev_idx; - *last_pix = prev_pix; -} - -// Remap argb values in src[] to packed palettes entries in dst[] -// using 'row' as a temporary buffer of size 'width'. -// We assume that all src[] values have a corresponding entry in the palette. -// Note: src[] can be the same as dst[] -static WebPEncodingError ApplyPalette(const uint32_t* src, uint32_t src_stride, - uint32_t* dst, uint32_t dst_stride, - const uint32_t* palette, int palette_size, - int width, int height, int xbits) { - // TODO(skal): this tmp buffer is not needed if VP8LBundleColorMap() can be - // made to work in-place. - uint8_t* const tmp_row = (uint8_t*)WebPSafeMalloc(width, sizeof(*tmp_row)); - int i, x, y; - int use_LUT = 1; - - if (tmp_row == NULL) return VP8_ENC_ERROR_OUT_OF_MEMORY; - for (i = 0; i < palette_size; ++i) { - if ((palette[i] & 0xffff00ffu) != 0) { - use_LUT = 0; - break; - } - } - - if (use_LUT) { - uint8_t inv_palette[MAX_PALETTE_SIZE] = { 0 }; - for (i = 0; i < palette_size; ++i) { - const int color = (palette[i] >> 8) & 0xff; - inv_palette[color] = i; - } - for (y = 0; y < height; ++y) { - for (x = 0; x < width; ++x) { - const int color = (src[x] >> 8) & 0xff; - tmp_row[x] = inv_palette[color]; - } - VP8LBundleColorMap(tmp_row, width, xbits, dst); - src += src_stride; - dst += dst_stride; - } - } else { - // Use 1 pixel cache for ARGB pixels. - uint32_t last_pix; - int last_idx; - uint32_t sorted[MAX_PALETTE_SIZE]; - int idx_map[MAX_PALETTE_SIZE]; - PrepareMapToPalette(palette, palette_size, sorted, idx_map); - last_pix = palette[0]; - last_idx = 0; - for (y = 0; y < height; ++y) { - MapToPalette(sorted, palette_size, &last_pix, &last_idx, - idx_map, src, tmp_row, width); - VP8LBundleColorMap(tmp_row, width, xbits, dst); - src += src_stride; - dst += dst_stride; - } - } - WebPSafeFree(tmp_row); - return VP8_ENC_OK; -} - -// Note: Expects "enc->palette_" to be set properly. -static WebPEncodingError MapImageFromPalette(VP8LEncoder* const enc, - int in_place) { - WebPEncodingError err = VP8_ENC_OK; - const WebPPicture* const pic = enc->pic_; - const int width = pic->width; - const int height = pic->height; - const uint32_t* const palette = enc->palette_; - const uint32_t* src = in_place ? enc->argb_ : pic->argb; - const int src_stride = in_place ? enc->current_width_ : pic->argb_stride; - const int palette_size = enc->palette_size_; - int xbits; - - // Replace each input pixel by corresponding palette index. - // This is done line by line. - if (palette_size <= 4) { - xbits = (palette_size <= 2) ? 3 : 2; - } else { - xbits = (palette_size <= 16) ? 1 : 0; - } - - err = AllocateTransformBuffer(enc, VP8LSubSampleSize(width, xbits), height); - if (err != VP8_ENC_OK) return err; - - err = ApplyPalette(src, src_stride, - enc->argb_, enc->current_width_, - palette, palette_size, width, height, xbits); - return err; -} - -// Save palette_[] to bitstream. -static WebPEncodingError EncodePalette(VP8LBitWriter* const bw, - VP8LEncoder* const enc) { - int i; - uint32_t tmp_palette[MAX_PALETTE_SIZE]; - const int palette_size = enc->palette_size_; - const uint32_t* const palette = enc->palette_; - VP8LPutBits(bw, TRANSFORM_PRESENT, 1); - VP8LPutBits(bw, COLOR_INDEXING_TRANSFORM, 2); - assert(palette_size >= 1 && palette_size <= MAX_PALETTE_SIZE); - VP8LPutBits(bw, palette_size - 1, 8); - for (i = palette_size - 1; i >= 1; --i) { - tmp_palette[i] = VP8LSubPixels(palette[i], palette[i - 1]); - } - tmp_palette[0] = palette[0]; - return EncodeImageNoHuffman(bw, tmp_palette, &enc->hash_chain_, enc->refs_, - palette_size, 1, 20 /* quality */); -} - -#ifdef WEBP_EXPERIMENTAL_FEATURES - -static WebPEncodingError EncodeDeltaPalettePredictorImage( - VP8LBitWriter* const bw, VP8LEncoder* const enc, int quality) { - const WebPPicture* const pic = enc->pic_; - const int width = pic->width; - const int height = pic->height; - - const int pred_bits = 5; - const int transform_width = VP8LSubSampleSize(width, pred_bits); - const int transform_height = VP8LSubSampleSize(height, pred_bits); - const int pred = 7; // default is Predictor7 (Top/Left Average) - const int tiles_per_row = VP8LSubSampleSize(width, pred_bits); - const int tiles_per_col = VP8LSubSampleSize(height, pred_bits); - uint32_t* predictors; - int tile_x, tile_y; - WebPEncodingError err = VP8_ENC_OK; - - predictors = (uint32_t*)WebPSafeMalloc(tiles_per_col * tiles_per_row, - sizeof(*predictors)); - if (predictors == NULL) return VP8_ENC_ERROR_OUT_OF_MEMORY; - - for (tile_y = 0; tile_y < tiles_per_col; ++tile_y) { - for (tile_x = 0; tile_x < tiles_per_row; ++tile_x) { - predictors[tile_y * tiles_per_row + tile_x] = 0xff000000u | (pred << 8); - } - } - - VP8LPutBits(bw, TRANSFORM_PRESENT, 1); - VP8LPutBits(bw, PREDICTOR_TRANSFORM, 2); - VP8LPutBits(bw, pred_bits - 2, 3); - err = EncodeImageNoHuffman(bw, predictors, &enc->hash_chain_, - (VP8LBackwardRefs*)enc->refs_, // cast const away - transform_width, transform_height, - quality); - WebPSafeFree(predictors); - return err; -} - -#endif // WEBP_EXPERIMENTAL_FEATURES - -// ----------------------------------------------------------------------------- -// VP8LEncoder - -static VP8LEncoder* VP8LEncoderNew(const WebPConfig* const config, - const WebPPicture* const picture) { - VP8LEncoder* const enc = (VP8LEncoder*)WebPSafeCalloc(1ULL, sizeof(*enc)); - if (enc == NULL) { - WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY); - return NULL; - } - enc->config_ = config; - enc->pic_ = picture; - - VP8LEncDspInit(); - - return enc; -} - -static void VP8LEncoderDelete(VP8LEncoder* enc) { - if (enc != NULL) { - VP8LHashChainClear(&enc->hash_chain_); - VP8LBackwardRefsClear(&enc->refs_[0]); - VP8LBackwardRefsClear(&enc->refs_[1]); - ClearTransformBuffer(enc); - WebPSafeFree(enc); - } -} - -// ----------------------------------------------------------------------------- -// Main call - -WebPEncodingError VP8LEncodeStream(const WebPConfig* const config, - const WebPPicture* const picture, - VP8LBitWriter* const bw, int use_cache) { - WebPEncodingError err = VP8_ENC_OK; - const int quality = (int)config->quality; - const int low_effort = (config->method == 0); - const int width = picture->width; - const int height = picture->height; - VP8LEncoder* const enc = VP8LEncoderNew(config, picture); - const size_t byte_position = VP8LBitWriterNumBytes(bw); - int use_near_lossless = 0; - int hdr_size = 0; - int data_size = 0; - int use_delta_palettization = 0; - - if (enc == NULL) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // --------------------------------------------------------------------------- - // Analyze image (entropy, num_palettes etc) - - if (!AnalyzeAndInit(enc)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - // Apply near-lossless preprocessing. - use_near_lossless = - (config->near_lossless < 100) && !enc->use_palette_ && !enc->use_predict_; - if (use_near_lossless) { - if (!VP8ApplyNearLossless(width, height, picture->argb, - config->near_lossless)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - } - -#ifdef WEBP_EXPERIMENTAL_FEATURES - if (config->delta_palettization) { - enc->use_predict_ = 1; - enc->use_cross_color_ = 0; - enc->use_subtract_green_ = 0; - enc->use_palette_ = 1; - err = MakeInputImageCopy(enc); - if (err != VP8_ENC_OK) goto Error; - err = WebPSearchOptimalDeltaPalette(enc); - if (err != VP8_ENC_OK) goto Error; - if (enc->use_palette_) { - err = AllocateTransformBuffer(enc, width, height); - if (err != VP8_ENC_OK) goto Error; - err = EncodeDeltaPalettePredictorImage(bw, enc, quality); - if (err != VP8_ENC_OK) goto Error; - use_delta_palettization = 1; - } - } -#endif // WEBP_EXPERIMENTAL_FEATURES - - // Encode palette - if (enc->use_palette_) { - err = EncodePalette(bw, enc); - if (err != VP8_ENC_OK) goto Error; - err = MapImageFromPalette(enc, use_delta_palettization); - if (err != VP8_ENC_OK) goto Error; - } - if (!use_delta_palettization) { - // In case image is not packed. - if (enc->argb_ == NULL) { - err = MakeInputImageCopy(enc); - if (err != VP8_ENC_OK) goto Error; - } - - // ------------------------------------------------------------------------- - // Apply transforms and write transform data. - - if (enc->use_subtract_green_) { - ApplySubtractGreen(enc, enc->current_width_, height, bw); - } - - if (enc->use_predict_) { - err = ApplyPredictFilter(enc, enc->current_width_, height, quality, - low_effort, enc->use_subtract_green_, bw); - if (err != VP8_ENC_OK) goto Error; - } - - if (enc->use_cross_color_) { - err = ApplyCrossColorFilter(enc, enc->current_width_, - height, quality, bw); - if (err != VP8_ENC_OK) goto Error; - } - } - - VP8LPutBits(bw, !TRANSFORM_PRESENT, 1); // No more transforms. - - // --------------------------------------------------------------------------- - // Encode and write the transformed image. - err = EncodeImageInternal(bw, enc->argb_, &enc->hash_chain_, enc->refs_, - enc->current_width_, height, quality, low_effort, - use_cache, &enc->cache_bits_, enc->histo_bits_, - byte_position, &hdr_size, &data_size); - if (err != VP8_ENC_OK) goto Error; - - if (picture->stats != NULL) { - WebPAuxStats* const stats = picture->stats; - stats->lossless_features = 0; - if (enc->use_predict_) stats->lossless_features |= 1; - if (enc->use_cross_color_) stats->lossless_features |= 2; - if (enc->use_subtract_green_) stats->lossless_features |= 4; - if (enc->use_palette_) stats->lossless_features |= 8; - stats->histogram_bits = enc->histo_bits_; - stats->transform_bits = enc->transform_bits_; - stats->cache_bits = enc->cache_bits_; - stats->palette_size = enc->palette_size_; - stats->lossless_size = (int)(VP8LBitWriterNumBytes(bw) - byte_position); - stats->lossless_hdr_size = hdr_size; - stats->lossless_data_size = data_size; - } - - Error: - VP8LEncoderDelete(enc); - return err; -} - -int VP8LEncodeImage(const WebPConfig* const config, - const WebPPicture* const picture) { - int width, height; - int has_alpha; - size_t coded_size; - int percent = 0; - int initial_size; - WebPEncodingError err = VP8_ENC_OK; - VP8LBitWriter bw; - - if (picture == NULL) return 0; - - if (config == NULL || picture->argb == NULL) { - err = VP8_ENC_ERROR_NULL_PARAMETER; - WebPEncodingSetError(picture, err); - return 0; - } - - width = picture->width; - height = picture->height; - // Initialize BitWriter with size corresponding to 16 bpp to photo images and - // 8 bpp for graphical images. - initial_size = (config->image_hint == WEBP_HINT_GRAPH) ? - width * height : width * height * 2; - if (!VP8LBitWriterInit(&bw, initial_size)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - if (!WebPReportProgress(picture, 1, &percent)) { - UserAbort: - err = VP8_ENC_ERROR_USER_ABORT; - goto Error; - } - // Reset stats (for pure lossless coding) - if (picture->stats != NULL) { - WebPAuxStats* const stats = picture->stats; - memset(stats, 0, sizeof(*stats)); - stats->PSNR[0] = 99.f; - stats->PSNR[1] = 99.f; - stats->PSNR[2] = 99.f; - stats->PSNR[3] = 99.f; - stats->PSNR[4] = 99.f; - } - - // Write image size. - if (!WriteImageSize(picture, &bw)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - has_alpha = WebPPictureHasTransparency(picture); - // Write the non-trivial Alpha flag and lossless version. - if (!WriteRealAlphaAndVersion(&bw, has_alpha)) { - err = VP8_ENC_ERROR_OUT_OF_MEMORY; - goto Error; - } - - if (!WebPReportProgress(picture, 5, &percent)) goto UserAbort; - - // Encode main image stream. - err = VP8LEncodeStream(config, picture, &bw, 1 /*use_cache*/); - if (err != VP8_ENC_OK) goto Error; - - // TODO(skal): have a fine-grained progress report in VP8LEncodeStream(). - if (!WebPReportProgress(picture, 90, &percent)) goto UserAbort; - - // Finish the RIFF chunk. - err = WriteImage(picture, &bw, &coded_size); - if (err != VP8_ENC_OK) goto Error; - - if (!WebPReportProgress(picture, 100, &percent)) goto UserAbort; - - // Save size. - if (picture->stats != NULL) { - picture->stats->coded_size += (int)coded_size; - picture->stats->lossless_size = (int)coded_size; - } - - if (picture->extra_info != NULL) { - const int mb_w = (width + 15) >> 4; - const int mb_h = (height + 15) >> 4; - memset(picture->extra_info, 0, mb_w * mb_h * sizeof(*picture->extra_info)); - } - - Error: - if (bw.error_) err = VP8_ENC_ERROR_OUT_OF_MEMORY; - VP8LBitWriterWipeOut(&bw); - if (err != VP8_ENC_OK) { - WebPEncodingSetError(picture, err); - return 0; - } - return 1; -} - -//------------------------------------------------------------------------------ |