diff options
Diffstat (limited to 'thirdparty/libwebp/src/dec/vp8l_dec.c')
| -rw-r--r-- | thirdparty/libwebp/src/dec/vp8l_dec.c | 121 |
1 files changed, 59 insertions, 62 deletions
diff --git a/thirdparty/libwebp/src/dec/vp8l_dec.c b/thirdparty/libwebp/src/dec/vp8l_dec.c index 333bb3e80d..d3e27119ea 100644 --- a/thirdparty/libwebp/src/dec/vp8l_dec.c +++ b/thirdparty/libwebp/src/dec/vp8l_dec.c @@ -362,12 +362,8 @@ static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, VP8LMetadata* const hdr = &dec->hdr_; uint32_t* huffman_image = NULL; HTreeGroup* htree_groups = NULL; - // When reading htrees, some might be unused, as the format allows it. - // We will still read them but put them in this htree_group_bogus. - HTreeGroup htree_group_bogus; HuffmanCode* huffman_tables = NULL; - HuffmanCode* huffman_tables_bogus = NULL; - HuffmanCode* next = NULL; + HuffmanCode* huffman_table = NULL; int num_htree_groups = 1; int num_htree_groups_max = 1; int max_alphabet_size = 0; @@ -418,12 +414,6 @@ static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, if (*mapped_group == -1) *mapped_group = num_htree_groups++; huffman_image[i] = *mapped_group; } - huffman_tables_bogus = (HuffmanCode*)WebPSafeMalloc( - table_size, sizeof(*huffman_tables_bogus)); - if (huffman_tables_bogus == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - goto Error; - } } else { num_htree_groups = num_htree_groups_max; } @@ -453,63 +443,71 @@ static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, goto Error; } - next = huffman_tables; + huffman_table = huffman_tables; for (i = 0; i < num_htree_groups_max; ++i) { - // If the index "i" is unused in the Huffman image, read the coefficients - // but store them to a bogus htree_group. - const int is_bogus = (mapping != NULL && mapping[i] == -1); - HTreeGroup* const htree_group = - is_bogus ? &htree_group_bogus : - &htree_groups[(mapping == NULL) ? i : mapping[i]]; - HuffmanCode** const htrees = htree_group->htrees; - HuffmanCode* huffman_tables_i = is_bogus ? huffman_tables_bogus : next; - 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] = huffman_tables_i; - if (j == 0 && color_cache_bits > 0) { - alphabet_size += 1 << color_cache_bits; - } - size = - ReadHuffmanCode(alphabet_size, dec, code_lengths, huffman_tables_i); - if (size == 0) { - goto Error; - } - if (is_trivial_literal && kLiteralMap[j] == 1) { - is_trivial_literal = (huffman_tables_i->bits == 0); + // If the index "i" is unused in the Huffman image, just make sure the + // coefficients are valid but do not store them. + if (mapping != NULL && mapping[i] == -1) { + 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); + } + // Passing in NULL so that nothing gets filled. + if (!ReadHuffmanCode(alphabet_size, dec, code_lengths, NULL)) { + goto Error; + } } - total_size += huffman_tables_i->bits; - huffman_tables_i += 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]; + } else { + HTreeGroup* const htree_group = + &htree_groups[(mapping == NULL) ? i : mapping[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] = huffman_table; + if (j == 0 && color_cache_bits > 0) { + alphabet_size += (1 << color_cache_bits); + } + size = ReadHuffmanCode(alphabet_size, dec, code_lengths, huffman_table); + if (size == 0) { + goto Error; + } + if (is_trivial_literal && kLiteralMap[j] == 1) { + is_trivial_literal = (huffman_table->bits == 0); + } + total_size += huffman_table->bits; + huffman_table += 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; } - max_bits += local_max_bits; } - } - if (!is_bogus) next = huffman_tables_i; - 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->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); } - htree_group->use_packed_table = - !htree_group->is_trivial_code && (max_bits < HUFFMAN_PACKED_BITS); - if (htree_group->use_packed_table) BuildPackedTable(htree_group); } ok = 1; @@ -521,7 +519,6 @@ static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, Error: WebPSafeFree(code_lengths); - WebPSafeFree(huffman_tables_bogus); WebPSafeFree(mapping); if (!ok) { WebPSafeFree(huffman_image); |