mirror of https://git.ffmpeg.org/ffmpeg.git
1514 lines
48 KiB
C
1514 lines
48 KiB
C
/*
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* WebP (.webp) image decoder
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* Copyright (c) 2013 Aneesh Dogra <aneesh@sugarlabs.org>
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* Copyright (c) 2013 Justin Ruggles <justin.ruggles@gmail.com>
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* WebP image decoder
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*
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* @author Aneesh Dogra <aneesh@sugarlabs.org>
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* Container and Lossy decoding
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*
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* @author Justin Ruggles <justin.ruggles@gmail.com>
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* Lossless decoder
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* Compressed alpha for lossy
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*
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* @author James Almer <jamrial@gmail.com>
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* Exif metadata
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*
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* Unimplemented:
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* - Animation
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* - ICC profile
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* - XMP metadata
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*/
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#define BITSTREAM_READER_LE
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#include "libavutil/imgutils.h"
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#include "avcodec.h"
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#include "bytestream.h"
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#include "exif.h"
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#include "internal.h"
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#include "get_bits.h"
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#include "thread.h"
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#include "vp8.h"
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#define VP8X_FLAG_ANIMATION 0x02
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#define VP8X_FLAG_XMP_METADATA 0x04
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#define VP8X_FLAG_EXIF_METADATA 0x08
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#define VP8X_FLAG_ALPHA 0x10
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#define VP8X_FLAG_ICC 0x20
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#define MAX_PALETTE_SIZE 256
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#define MAX_CACHE_BITS 11
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#define NUM_CODE_LENGTH_CODES 19
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#define HUFFMAN_CODES_PER_META_CODE 5
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#define NUM_LITERAL_CODES 256
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#define NUM_LENGTH_CODES 24
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#define NUM_DISTANCE_CODES 40
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#define NUM_SHORT_DISTANCES 120
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#define MAX_HUFFMAN_CODE_LENGTH 15
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static const uint16_t alphabet_sizes[HUFFMAN_CODES_PER_META_CODE] = {
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NUM_LITERAL_CODES + NUM_LENGTH_CODES,
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NUM_LITERAL_CODES, NUM_LITERAL_CODES, NUM_LITERAL_CODES,
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NUM_DISTANCE_CODES
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};
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static const uint8_t code_length_code_order[NUM_CODE_LENGTH_CODES] = {
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17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
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};
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static const int8_t lz77_distance_offsets[NUM_SHORT_DISTANCES][2] = {
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{ 0, 1 }, { 1, 0 }, { 1, 1 }, { -1, 1 }, { 0, 2 }, { 2, 0 }, { 1, 2 }, { -1, 2 },
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{ 2, 1 }, { -2, 1 }, { 2, 2 }, { -2, 2 }, { 0, 3 }, { 3, 0 }, { 1, 3 }, { -1, 3 },
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{ 3, 1 }, { -3, 1 }, { 2, 3 }, { -2, 3 }, { 3, 2 }, { -3, 2 }, { 0, 4 }, { 4, 0 },
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{ 1, 4 }, { -1, 4 }, { 4, 1 }, { -4, 1 }, { 3, 3 }, { -3, 3 }, { 2, 4 }, { -2, 4 },
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{ 4, 2 }, { -4, 2 }, { 0, 5 }, { 3, 4 }, { -3, 4 }, { 4, 3 }, { -4, 3 }, { 5, 0 },
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{ 1, 5 }, { -1, 5 }, { 5, 1 }, { -5, 1 }, { 2, 5 }, { -2, 5 }, { 5, 2 }, { -5, 2 },
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{ 4, 4 }, { -4, 4 }, { 3, 5 }, { -3, 5 }, { 5, 3 }, { -5, 3 }, { 0, 6 }, { 6, 0 },
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{ 1, 6 }, { -1, 6 }, { 6, 1 }, { -6, 1 }, { 2, 6 }, { -2, 6 }, { 6, 2 }, { -6, 2 },
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{ 4, 5 }, { -4, 5 }, { 5, 4 }, { -5, 4 }, { 3, 6 }, { -3, 6 }, { 6, 3 }, { -6, 3 },
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{ 0, 7 }, { 7, 0 }, { 1, 7 }, { -1, 7 }, { 5, 5 }, { -5, 5 }, { 7, 1 }, { -7, 1 },
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{ 4, 6 }, { -4, 6 }, { 6, 4 }, { -6, 4 }, { 2, 7 }, { -2, 7 }, { 7, 2 }, { -7, 2 },
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{ 3, 7 }, { -3, 7 }, { 7, 3 }, { -7, 3 }, { 5, 6 }, { -5, 6 }, { 6, 5 }, { -6, 5 },
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{ 8, 0 }, { 4, 7 }, { -4, 7 }, { 7, 4 }, { -7, 4 }, { 8, 1 }, { 8, 2 }, { 6, 6 },
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{ -6, 6 }, { 8, 3 }, { 5, 7 }, { -5, 7 }, { 7, 5 }, { -7, 5 }, { 8, 4 }, { 6, 7 },
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{ -6, 7 }, { 7, 6 }, { -7, 6 }, { 8, 5 }, { 7, 7 }, { -7, 7 }, { 8, 6 }, { 8, 7 }
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};
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enum AlphaCompression {
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ALPHA_COMPRESSION_NONE,
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ALPHA_COMPRESSION_VP8L,
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};
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enum AlphaFilter {
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ALPHA_FILTER_NONE,
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ALPHA_FILTER_HORIZONTAL,
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ALPHA_FILTER_VERTICAL,
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ALPHA_FILTER_GRADIENT,
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};
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enum TransformType {
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PREDICTOR_TRANSFORM = 0,
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COLOR_TRANSFORM = 1,
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SUBTRACT_GREEN = 2,
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COLOR_INDEXING_TRANSFORM = 3,
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};
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enum PredictionMode {
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PRED_MODE_BLACK,
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PRED_MODE_L,
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PRED_MODE_T,
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PRED_MODE_TR,
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PRED_MODE_TL,
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PRED_MODE_AVG_T_AVG_L_TR,
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PRED_MODE_AVG_L_TL,
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PRED_MODE_AVG_L_T,
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PRED_MODE_AVG_TL_T,
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PRED_MODE_AVG_T_TR,
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PRED_MODE_AVG_AVG_L_TL_AVG_T_TR,
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PRED_MODE_SELECT,
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PRED_MODE_ADD_SUBTRACT_FULL,
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PRED_MODE_ADD_SUBTRACT_HALF,
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};
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enum HuffmanIndex {
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HUFF_IDX_GREEN = 0,
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HUFF_IDX_RED = 1,
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HUFF_IDX_BLUE = 2,
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HUFF_IDX_ALPHA = 3,
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HUFF_IDX_DIST = 4
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};
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/* The structure of WebP lossless is an optional series of transformation data,
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* followed by the primary image. The primary image also optionally contains
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* an entropy group mapping if there are multiple entropy groups. There is a
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* basic image type called an "entropy coded image" that is used for all of
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* these. The type of each entropy coded image is referred to by the
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* specification as its role. */
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enum ImageRole {
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/* Primary Image: Stores the actual pixels of the image. */
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IMAGE_ROLE_ARGB,
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/* Entropy Image: Defines which Huffman group to use for different areas of
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* the primary image. */
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IMAGE_ROLE_ENTROPY,
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/* Predictors: Defines which predictor type to use for different areas of
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* the primary image. */
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IMAGE_ROLE_PREDICTOR,
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/* Color Transform Data: Defines the color transformation for different
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* areas of the primary image. */
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IMAGE_ROLE_COLOR_TRANSFORM,
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/* Color Index: Stored as an image of height == 1. */
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IMAGE_ROLE_COLOR_INDEXING,
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IMAGE_ROLE_NB,
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};
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typedef struct HuffReader {
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VLC vlc; /* Huffman decoder context */
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int simple; /* whether to use simple mode */
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int nb_symbols; /* number of coded symbols */
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uint16_t simple_symbols[2]; /* symbols for simple mode */
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} HuffReader;
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typedef struct ImageContext {
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enum ImageRole role; /* role of this image */
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AVFrame *frame; /* AVFrame for data */
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int color_cache_bits; /* color cache size, log2 */
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uint32_t *color_cache; /* color cache data */
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int nb_huffman_groups; /* number of huffman groups */
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HuffReader *huffman_groups; /* reader for each huffman group */
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int size_reduction; /* relative size compared to primary image, log2 */
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int is_alpha_primary;
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} ImageContext;
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typedef struct WebPContext {
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VP8Context v; /* VP8 Context used for lossy decoding */
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GetBitContext gb; /* bitstream reader for main image chunk */
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AVFrame *alpha_frame; /* AVFrame for alpha data decompressed from VP8L */
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AVCodecContext *avctx; /* parent AVCodecContext */
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int initialized; /* set once the VP8 context is initialized */
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int has_alpha; /* has a separate alpha chunk */
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enum AlphaCompression alpha_compression; /* compression type for alpha chunk */
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enum AlphaFilter alpha_filter; /* filtering method for alpha chunk */
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uint8_t *alpha_data; /* alpha chunk data */
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int alpha_data_size; /* alpha chunk data size */
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int has_exif; /* set after an EXIF chunk has been processed */
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AVDictionary *exif_metadata; /* EXIF chunk data */
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int width; /* image width */
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int height; /* image height */
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int lossless; /* indicates lossless or lossy */
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int nb_transforms; /* number of transforms */
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enum TransformType transforms[4]; /* transformations used in the image, in order */
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int reduced_width; /* reduced width for index image, if applicable */
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int nb_huffman_groups; /* number of huffman groups in the primary image */
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ImageContext image[IMAGE_ROLE_NB]; /* image context for each role */
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} WebPContext;
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#define GET_PIXEL(frame, x, y) \
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((frame)->data[0] + (y) * frame->linesize[0] + 4 * (x))
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#define GET_PIXEL_COMP(frame, x, y, c) \
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(*((frame)->data[0] + (y) * frame->linesize[0] + 4 * (x) + c))
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static void image_ctx_free(ImageContext *img)
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{
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int i, j;
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av_free(img->color_cache);
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if (img->role != IMAGE_ROLE_ARGB && !img->is_alpha_primary)
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av_frame_free(&img->frame);
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if (img->huffman_groups) {
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for (i = 0; i < img->nb_huffman_groups; i++) {
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for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; j++)
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ff_free_vlc(&img->huffman_groups[i * HUFFMAN_CODES_PER_META_CODE + j].vlc);
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}
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av_free(img->huffman_groups);
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}
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memset(img, 0, sizeof(*img));
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}
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/* Differs from get_vlc2() in the following ways:
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* - codes are bit-reversed
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* - assumes 8-bit table to make reversal simpler
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* - assumes max depth of 2 since the max code length for WebP is 15
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*/
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static av_always_inline int webp_get_vlc(GetBitContext *gb, VLC_TYPE (*table)[2])
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{
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int n, nb_bits;
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unsigned int index;
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int code;
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OPEN_READER(re, gb);
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UPDATE_CACHE(re, gb);
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index = SHOW_UBITS(re, gb, 8);
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index = ff_reverse[index];
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code = table[index][0];
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n = table[index][1];
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if (n < 0) {
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LAST_SKIP_BITS(re, gb, 8);
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UPDATE_CACHE(re, gb);
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nb_bits = -n;
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index = SHOW_UBITS(re, gb, nb_bits);
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index = (ff_reverse[index] >> (8 - nb_bits)) + code;
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code = table[index][0];
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n = table[index][1];
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}
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SKIP_BITS(re, gb, n);
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CLOSE_READER(re, gb);
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return code;
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}
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static int huff_reader_get_symbol(HuffReader *r, GetBitContext *gb)
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{
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if (r->simple) {
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if (r->nb_symbols == 1)
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return r->simple_symbols[0];
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else
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return r->simple_symbols[get_bits1(gb)];
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} else
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return webp_get_vlc(gb, r->vlc.table);
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}
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static int huff_reader_build_canonical(HuffReader *r, int *code_lengths,
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int alphabet_size)
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{
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int len = 0, sym, code = 0, ret;
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int max_code_length = 0;
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uint16_t *codes;
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/* special-case 1 symbol since the vlc reader cannot handle it */
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for (sym = 0; sym < alphabet_size; sym++) {
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if (code_lengths[sym] > 0) {
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len++;
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code = sym;
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if (len > 1)
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break;
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}
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}
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if (len == 1) {
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r->nb_symbols = 1;
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r->simple_symbols[0] = code;
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r->simple = 1;
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return 0;
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}
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for (sym = 0; sym < alphabet_size; sym++)
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max_code_length = FFMAX(max_code_length, code_lengths[sym]);
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if (max_code_length == 0 || max_code_length > MAX_HUFFMAN_CODE_LENGTH)
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return AVERROR(EINVAL);
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codes = av_malloc_array(alphabet_size, sizeof(*codes));
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if (!codes)
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return AVERROR(ENOMEM);
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code = 0;
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r->nb_symbols = 0;
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for (len = 1; len <= max_code_length; len++) {
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for (sym = 0; sym < alphabet_size; sym++) {
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if (code_lengths[sym] != len)
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continue;
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codes[sym] = code++;
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r->nb_symbols++;
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}
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code <<= 1;
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}
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if (!r->nb_symbols) {
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av_free(codes);
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return AVERROR_INVALIDDATA;
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}
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ret = init_vlc(&r->vlc, 8, alphabet_size,
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code_lengths, sizeof(*code_lengths), sizeof(*code_lengths),
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codes, sizeof(*codes), sizeof(*codes), 0);
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if (ret < 0) {
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av_free(codes);
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return ret;
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}
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r->simple = 0;
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av_free(codes);
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return 0;
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}
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static void read_huffman_code_simple(WebPContext *s, HuffReader *hc)
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{
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hc->nb_symbols = get_bits1(&s->gb) + 1;
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if (get_bits1(&s->gb))
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hc->simple_symbols[0] = get_bits(&s->gb, 8);
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else
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hc->simple_symbols[0] = get_bits1(&s->gb);
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if (hc->nb_symbols == 2)
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hc->simple_symbols[1] = get_bits(&s->gb, 8);
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hc->simple = 1;
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}
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static int read_huffman_code_normal(WebPContext *s, HuffReader *hc,
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int alphabet_size)
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{
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HuffReader code_len_hc = { { 0 }, 0, 0, { 0 } };
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int *code_lengths = NULL;
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int code_length_code_lengths[NUM_CODE_LENGTH_CODES] = { 0 };
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int i, symbol, max_symbol, prev_code_len, ret;
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int num_codes = 4 + get_bits(&s->gb, 4);
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if (num_codes > NUM_CODE_LENGTH_CODES)
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return AVERROR_INVALIDDATA;
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for (i = 0; i < num_codes; i++)
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code_length_code_lengths[code_length_code_order[i]] = get_bits(&s->gb, 3);
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ret = huff_reader_build_canonical(&code_len_hc, code_length_code_lengths,
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NUM_CODE_LENGTH_CODES);
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if (ret < 0)
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goto finish;
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code_lengths = av_mallocz_array(alphabet_size, sizeof(*code_lengths));
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if (!code_lengths) {
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ret = AVERROR(ENOMEM);
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goto finish;
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}
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if (get_bits1(&s->gb)) {
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int bits = 2 + 2 * get_bits(&s->gb, 3);
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max_symbol = 2 + get_bits(&s->gb, bits);
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if (max_symbol > alphabet_size) {
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av_log(s->avctx, AV_LOG_ERROR, "max symbol %d > alphabet size %d\n",
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max_symbol, alphabet_size);
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ret = AVERROR_INVALIDDATA;
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goto finish;
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}
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} else {
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max_symbol = alphabet_size;
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}
|
|
|
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prev_code_len = 8;
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symbol = 0;
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while (symbol < alphabet_size) {
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int code_len;
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|
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if (!max_symbol--)
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break;
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code_len = huff_reader_get_symbol(&code_len_hc, &s->gb);
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if (code_len < 16) {
|
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/* Code length code [0..15] indicates literal code lengths. */
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code_lengths[symbol++] = code_len;
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if (code_len)
|
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prev_code_len = code_len;
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} else {
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int repeat = 0, length = 0;
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switch (code_len) {
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case 16:
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/* Code 16 repeats the previous non-zero value [3..6] times,
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* i.e., 3 + ReadBits(2) times. If code 16 is used before a
|
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* non-zero value has been emitted, a value of 8 is repeated. */
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repeat = 3 + get_bits(&s->gb, 2);
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length = prev_code_len;
|
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break;
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case 17:
|
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/* Code 17 emits a streak of zeros [3..10], i.e.,
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* 3 + ReadBits(3) times. */
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repeat = 3 + get_bits(&s->gb, 3);
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break;
|
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case 18:
|
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/* Code 18 emits a streak of zeros of length [11..138], i.e.,
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* 11 + ReadBits(7) times. */
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repeat = 11 + get_bits(&s->gb, 7);
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break;
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}
|
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if (symbol + repeat > alphabet_size) {
|
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av_log(s->avctx, AV_LOG_ERROR,
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"invalid symbol %d + repeat %d > alphabet size %d\n",
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symbol, repeat, alphabet_size);
|
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ret = AVERROR_INVALIDDATA;
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goto finish;
|
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}
|
|
while (repeat-- > 0)
|
|
code_lengths[symbol++] = length;
|
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}
|
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}
|
|
|
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ret = huff_reader_build_canonical(hc, code_lengths, alphabet_size);
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|
|
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finish:
|
|
ff_free_vlc(&code_len_hc.vlc);
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av_free(code_lengths);
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return ret;
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|
}
|
|
|
|
static int decode_entropy_coded_image(WebPContext *s, enum ImageRole role,
|
|
int w, int h);
|
|
|
|
#define PARSE_BLOCK_SIZE(w, h) do { \
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|
block_bits = get_bits(&s->gb, 3) + 2; \
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|
blocks_w = FFALIGN((w), 1 << block_bits) >> block_bits; \
|
|
blocks_h = FFALIGN((h), 1 << block_bits) >> block_bits; \
|
|
} while (0)
|
|
|
|
static int decode_entropy_image(WebPContext *s)
|
|
{
|
|
ImageContext *img;
|
|
int ret, block_bits, width, blocks_w, blocks_h, x, y, max;
|
|
|
|
width = s->width;
|
|
if (s->reduced_width > 0)
|
|
width = s->reduced_width;
|
|
|
|
PARSE_BLOCK_SIZE(width, s->height);
|
|
|
|
ret = decode_entropy_coded_image(s, IMAGE_ROLE_ENTROPY, blocks_w, blocks_h);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
img = &s->image[IMAGE_ROLE_ENTROPY];
|
|
img->size_reduction = block_bits;
|
|
|
|
/* the number of huffman groups is determined by the maximum group number
|
|
* coded in the entropy image */
|
|
max = 0;
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
int p0 = GET_PIXEL_COMP(img->frame, x, y, 1);
|
|
int p1 = GET_PIXEL_COMP(img->frame, x, y, 2);
|
|
int p = p0 << 8 | p1;
|
|
max = FFMAX(max, p);
|
|
}
|
|
}
|
|
s->nb_huffman_groups = max + 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int parse_transform_predictor(WebPContext *s)
|
|
{
|
|
int block_bits, blocks_w, blocks_h, ret;
|
|
|
|
PARSE_BLOCK_SIZE(s->width, s->height);
|
|
|
|
ret = decode_entropy_coded_image(s, IMAGE_ROLE_PREDICTOR, blocks_w,
|
|
blocks_h);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
s->image[IMAGE_ROLE_PREDICTOR].size_reduction = block_bits;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int parse_transform_color(WebPContext *s)
|
|
{
|
|
int block_bits, blocks_w, blocks_h, ret;
|
|
|
|
PARSE_BLOCK_SIZE(s->width, s->height);
|
|
|
|
ret = decode_entropy_coded_image(s, IMAGE_ROLE_COLOR_TRANSFORM, blocks_w,
|
|
blocks_h);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
s->image[IMAGE_ROLE_COLOR_TRANSFORM].size_reduction = block_bits;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int parse_transform_color_indexing(WebPContext *s)
|
|
{
|
|
ImageContext *img;
|
|
int width_bits, index_size, ret, x;
|
|
uint8_t *ct;
|
|
|
|
index_size = get_bits(&s->gb, 8) + 1;
|
|
|
|
if (index_size <= 2)
|
|
width_bits = 3;
|
|
else if (index_size <= 4)
|
|
width_bits = 2;
|
|
else if (index_size <= 16)
|
|
width_bits = 1;
|
|
else
|
|
width_bits = 0;
|
|
|
|
ret = decode_entropy_coded_image(s, IMAGE_ROLE_COLOR_INDEXING,
|
|
index_size, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
img = &s->image[IMAGE_ROLE_COLOR_INDEXING];
|
|
img->size_reduction = width_bits;
|
|
if (width_bits > 0)
|
|
s->reduced_width = (s->width + ((1 << width_bits) - 1)) >> width_bits;
|
|
|
|
/* color index values are delta-coded */
|
|
ct = img->frame->data[0] + 4;
|
|
for (x = 4; x < img->frame->width * 4; x++, ct++)
|
|
ct[0] += ct[-4];
|
|
|
|
return 0;
|
|
}
|
|
|
|
static HuffReader *get_huffman_group(WebPContext *s, ImageContext *img,
|
|
int x, int y)
|
|
{
|
|
ImageContext *gimg = &s->image[IMAGE_ROLE_ENTROPY];
|
|
int group = 0;
|
|
|
|
if (gimg->size_reduction > 0) {
|
|
int group_x = x >> gimg->size_reduction;
|
|
int group_y = y >> gimg->size_reduction;
|
|
int g0 = GET_PIXEL_COMP(gimg->frame, group_x, group_y, 1);
|
|
int g1 = GET_PIXEL_COMP(gimg->frame, group_x, group_y, 2);
|
|
group = g0 << 8 | g1;
|
|
}
|
|
|
|
return &img->huffman_groups[group * HUFFMAN_CODES_PER_META_CODE];
|
|
}
|
|
|
|
static av_always_inline void color_cache_put(ImageContext *img, uint32_t c)
|
|
{
|
|
uint32_t cache_idx = (0x1E35A7BD * c) >> (32 - img->color_cache_bits);
|
|
img->color_cache[cache_idx] = c;
|
|
}
|
|
|
|
static int decode_entropy_coded_image(WebPContext *s, enum ImageRole role,
|
|
int w, int h)
|
|
{
|
|
ImageContext *img;
|
|
HuffReader *hg;
|
|
int i, j, ret, x, y, width;
|
|
|
|
img = &s->image[role];
|
|
img->role = role;
|
|
|
|
if (!img->frame) {
|
|
img->frame = av_frame_alloc();
|
|
if (!img->frame)
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
|
|
img->frame->format = AV_PIX_FMT_ARGB;
|
|
img->frame->width = w;
|
|
img->frame->height = h;
|
|
|
|
if (role == IMAGE_ROLE_ARGB && !img->is_alpha_primary) {
|
|
ThreadFrame pt = { .f = img->frame };
|
|
ret = ff_thread_get_buffer(s->avctx, &pt, 0);
|
|
} else
|
|
ret = av_frame_get_buffer(img->frame, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (get_bits1(&s->gb)) {
|
|
img->color_cache_bits = get_bits(&s->gb, 4);
|
|
if (img->color_cache_bits < 1 || img->color_cache_bits > 11) {
|
|
av_log(s->avctx, AV_LOG_ERROR, "invalid color cache bits: %d\n",
|
|
img->color_cache_bits);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
img->color_cache = av_mallocz_array(1 << img->color_cache_bits,
|
|
sizeof(*img->color_cache));
|
|
if (!img->color_cache)
|
|
return AVERROR(ENOMEM);
|
|
} else {
|
|
img->color_cache_bits = 0;
|
|
}
|
|
|
|
img->nb_huffman_groups = 1;
|
|
if (role == IMAGE_ROLE_ARGB && get_bits1(&s->gb)) {
|
|
ret = decode_entropy_image(s);
|
|
if (ret < 0)
|
|
return ret;
|
|
img->nb_huffman_groups = s->nb_huffman_groups;
|
|
}
|
|
img->huffman_groups = av_mallocz_array(img->nb_huffman_groups *
|
|
HUFFMAN_CODES_PER_META_CODE,
|
|
sizeof(*img->huffman_groups));
|
|
if (!img->huffman_groups)
|
|
return AVERROR(ENOMEM);
|
|
|
|
for (i = 0; i < img->nb_huffman_groups; i++) {
|
|
hg = &img->huffman_groups[i * HUFFMAN_CODES_PER_META_CODE];
|
|
for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; j++) {
|
|
int alphabet_size = alphabet_sizes[j];
|
|
if (!j && img->color_cache_bits > 0)
|
|
alphabet_size += 1 << img->color_cache_bits;
|
|
|
|
if (get_bits1(&s->gb)) {
|
|
read_huffman_code_simple(s, &hg[j]);
|
|
} else {
|
|
ret = read_huffman_code_normal(s, &hg[j], alphabet_size);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
}
|
|
}
|
|
|
|
width = img->frame->width;
|
|
if (role == IMAGE_ROLE_ARGB && s->reduced_width > 0)
|
|
width = s->reduced_width;
|
|
|
|
x = 0; y = 0;
|
|
while (y < img->frame->height) {
|
|
int v;
|
|
|
|
hg = get_huffman_group(s, img, x, y);
|
|
v = huff_reader_get_symbol(&hg[HUFF_IDX_GREEN], &s->gb);
|
|
if (v < NUM_LITERAL_CODES) {
|
|
/* literal pixel values */
|
|
uint8_t *p = GET_PIXEL(img->frame, x, y);
|
|
p[2] = v;
|
|
p[1] = huff_reader_get_symbol(&hg[HUFF_IDX_RED], &s->gb);
|
|
p[3] = huff_reader_get_symbol(&hg[HUFF_IDX_BLUE], &s->gb);
|
|
p[0] = huff_reader_get_symbol(&hg[HUFF_IDX_ALPHA], &s->gb);
|
|
if (img->color_cache_bits)
|
|
color_cache_put(img, AV_RB32(p));
|
|
x++;
|
|
if (x == width) {
|
|
x = 0;
|
|
y++;
|
|
}
|
|
} else if (v < NUM_LITERAL_CODES + NUM_LENGTH_CODES) {
|
|
/* LZ77 backwards mapping */
|
|
int prefix_code, length, distance, ref_x, ref_y;
|
|
|
|
/* parse length and distance */
|
|
prefix_code = v - NUM_LITERAL_CODES;
|
|
if (prefix_code < 4) {
|
|
length = prefix_code + 1;
|
|
} else {
|
|
int extra_bits = (prefix_code - 2) >> 1;
|
|
int offset = 2 + (prefix_code & 1) << extra_bits;
|
|
length = offset + get_bits(&s->gb, extra_bits) + 1;
|
|
}
|
|
prefix_code = huff_reader_get_symbol(&hg[HUFF_IDX_DIST], &s->gb);
|
|
if (prefix_code < 4) {
|
|
distance = prefix_code + 1;
|
|
} else {
|
|
int extra_bits = prefix_code - 2 >> 1;
|
|
int offset = 2 + (prefix_code & 1) << extra_bits;
|
|
distance = offset + get_bits(&s->gb, extra_bits) + 1;
|
|
}
|
|
|
|
/* find reference location */
|
|
if (distance <= NUM_SHORT_DISTANCES) {
|
|
int xi = lz77_distance_offsets[distance - 1][0];
|
|
int yi = lz77_distance_offsets[distance - 1][1];
|
|
distance = FFMAX(1, xi + yi * width);
|
|
} else {
|
|
distance -= NUM_SHORT_DISTANCES;
|
|
}
|
|
ref_x = x;
|
|
ref_y = y;
|
|
if (distance <= x) {
|
|
ref_x -= distance;
|
|
distance = 0;
|
|
} else {
|
|
ref_x = 0;
|
|
distance -= x;
|
|
}
|
|
while (distance >= width) {
|
|
ref_y--;
|
|
distance -= width;
|
|
}
|
|
if (distance > 0) {
|
|
ref_x = width - distance;
|
|
ref_y--;
|
|
}
|
|
ref_x = FFMAX(0, ref_x);
|
|
ref_y = FFMAX(0, ref_y);
|
|
|
|
/* copy pixels
|
|
* source and dest regions can overlap and wrap lines, so just
|
|
* copy per-pixel */
|
|
for (i = 0; i < length; i++) {
|
|
uint8_t *p_ref = GET_PIXEL(img->frame, ref_x, ref_y);
|
|
uint8_t *p = GET_PIXEL(img->frame, x, y);
|
|
|
|
AV_COPY32(p, p_ref);
|
|
if (img->color_cache_bits)
|
|
color_cache_put(img, AV_RB32(p));
|
|
x++;
|
|
ref_x++;
|
|
if (x == width) {
|
|
x = 0;
|
|
y++;
|
|
}
|
|
if (ref_x == width) {
|
|
ref_x = 0;
|
|
ref_y++;
|
|
}
|
|
if (y == img->frame->height || ref_y == img->frame->height)
|
|
break;
|
|
}
|
|
} else {
|
|
/* read from color cache */
|
|
uint8_t *p = GET_PIXEL(img->frame, x, y);
|
|
int cache_idx = v - (NUM_LITERAL_CODES + NUM_LENGTH_CODES);
|
|
|
|
if (!img->color_cache_bits) {
|
|
av_log(s->avctx, AV_LOG_ERROR, "color cache not found\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
if (cache_idx >= 1 << img->color_cache_bits) {
|
|
av_log(s->avctx, AV_LOG_ERROR,
|
|
"color cache index out-of-bounds\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
AV_WB32(p, img->color_cache[cache_idx]);
|
|
x++;
|
|
if (x == width) {
|
|
x = 0;
|
|
y++;
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* PRED_MODE_BLACK */
|
|
static void inv_predict_0(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
AV_WB32(p, 0xFF000000);
|
|
}
|
|
|
|
/* PRED_MODE_L */
|
|
static void inv_predict_1(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
AV_COPY32(p, p_l);
|
|
}
|
|
|
|
/* PRED_MODE_T */
|
|
static void inv_predict_2(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
AV_COPY32(p, p_t);
|
|
}
|
|
|
|
/* PRED_MODE_TR */
|
|
static void inv_predict_3(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
AV_COPY32(p, p_tr);
|
|
}
|
|
|
|
/* PRED_MODE_TL */
|
|
static void inv_predict_4(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
AV_COPY32(p, p_tl);
|
|
}
|
|
|
|
/* PRED_MODE_AVG_T_AVG_L_TR */
|
|
static void inv_predict_5(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = p_t[0] + (p_l[0] + p_tr[0] >> 1) >> 1;
|
|
p[1] = p_t[1] + (p_l[1] + p_tr[1] >> 1) >> 1;
|
|
p[2] = p_t[2] + (p_l[2] + p_tr[2] >> 1) >> 1;
|
|
p[3] = p_t[3] + (p_l[3] + p_tr[3] >> 1) >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_AVG_L_TL */
|
|
static void inv_predict_6(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = p_l[0] + p_tl[0] >> 1;
|
|
p[1] = p_l[1] + p_tl[1] >> 1;
|
|
p[2] = p_l[2] + p_tl[2] >> 1;
|
|
p[3] = p_l[3] + p_tl[3] >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_AVG_L_T */
|
|
static void inv_predict_7(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = p_l[0] + p_t[0] >> 1;
|
|
p[1] = p_l[1] + p_t[1] >> 1;
|
|
p[2] = p_l[2] + p_t[2] >> 1;
|
|
p[3] = p_l[3] + p_t[3] >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_AVG_TL_T */
|
|
static void inv_predict_8(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = p_tl[0] + p_t[0] >> 1;
|
|
p[1] = p_tl[1] + p_t[1] >> 1;
|
|
p[2] = p_tl[2] + p_t[2] >> 1;
|
|
p[3] = p_tl[3] + p_t[3] >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_AVG_T_TR */
|
|
static void inv_predict_9(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = p_t[0] + p_tr[0] >> 1;
|
|
p[1] = p_t[1] + p_tr[1] >> 1;
|
|
p[2] = p_t[2] + p_tr[2] >> 1;
|
|
p[3] = p_t[3] + p_tr[3] >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_AVG_AVG_L_TL_AVG_T_TR */
|
|
static void inv_predict_10(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = (p_l[0] + p_tl[0] >> 1) + (p_t[0] + p_tr[0] >> 1) >> 1;
|
|
p[1] = (p_l[1] + p_tl[1] >> 1) + (p_t[1] + p_tr[1] >> 1) >> 1;
|
|
p[2] = (p_l[2] + p_tl[2] >> 1) + (p_t[2] + p_tr[2] >> 1) >> 1;
|
|
p[3] = (p_l[3] + p_tl[3] >> 1) + (p_t[3] + p_tr[3] >> 1) >> 1;
|
|
}
|
|
|
|
/* PRED_MODE_SELECT */
|
|
static void inv_predict_11(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
int diff = (FFABS(p_l[0] - p_tl[0]) - FFABS(p_t[0] - p_tl[0])) +
|
|
(FFABS(p_l[1] - p_tl[1]) - FFABS(p_t[1] - p_tl[1])) +
|
|
(FFABS(p_l[2] - p_tl[2]) - FFABS(p_t[2] - p_tl[2])) +
|
|
(FFABS(p_l[3] - p_tl[3]) - FFABS(p_t[3] - p_tl[3]));
|
|
if (diff <= 0)
|
|
AV_COPY32(p, p_t);
|
|
else
|
|
AV_COPY32(p, p_l);
|
|
}
|
|
|
|
/* PRED_MODE_ADD_SUBTRACT_FULL */
|
|
static void inv_predict_12(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = av_clip_uint8(p_l[0] + p_t[0] - p_tl[0]);
|
|
p[1] = av_clip_uint8(p_l[1] + p_t[1] - p_tl[1]);
|
|
p[2] = av_clip_uint8(p_l[2] + p_t[2] - p_tl[2]);
|
|
p[3] = av_clip_uint8(p_l[3] + p_t[3] - p_tl[3]);
|
|
}
|
|
|
|
static av_always_inline uint8_t clamp_add_subtract_half(int a, int b, int c)
|
|
{
|
|
int d = a + b >> 1;
|
|
return av_clip_uint8(d + (d - c) / 2);
|
|
}
|
|
|
|
/* PRED_MODE_ADD_SUBTRACT_HALF */
|
|
static void inv_predict_13(uint8_t *p, const uint8_t *p_l, const uint8_t *p_tl,
|
|
const uint8_t *p_t, const uint8_t *p_tr)
|
|
{
|
|
p[0] = clamp_add_subtract_half(p_l[0], p_t[0], p_tl[0]);
|
|
p[1] = clamp_add_subtract_half(p_l[1], p_t[1], p_tl[1]);
|
|
p[2] = clamp_add_subtract_half(p_l[2], p_t[2], p_tl[2]);
|
|
p[3] = clamp_add_subtract_half(p_l[3], p_t[3], p_tl[3]);
|
|
}
|
|
|
|
typedef void (*inv_predict_func)(uint8_t *p, const uint8_t *p_l,
|
|
const uint8_t *p_tl, const uint8_t *p_t,
|
|
const uint8_t *p_tr);
|
|
|
|
static const inv_predict_func inverse_predict[14] = {
|
|
inv_predict_0, inv_predict_1, inv_predict_2, inv_predict_3,
|
|
inv_predict_4, inv_predict_5, inv_predict_6, inv_predict_7,
|
|
inv_predict_8, inv_predict_9, inv_predict_10, inv_predict_11,
|
|
inv_predict_12, inv_predict_13,
|
|
};
|
|
|
|
static void inverse_prediction(AVFrame *frame, enum PredictionMode m, int x, int y)
|
|
{
|
|
uint8_t *dec, *p_l, *p_tl, *p_t, *p_tr;
|
|
uint8_t p[4];
|
|
|
|
dec = GET_PIXEL(frame, x, y);
|
|
p_l = GET_PIXEL(frame, x - 1, y);
|
|
p_tl = GET_PIXEL(frame, x - 1, y - 1);
|
|
p_t = GET_PIXEL(frame, x, y - 1);
|
|
if (x == frame->width - 1)
|
|
p_tr = GET_PIXEL(frame, 0, y);
|
|
else
|
|
p_tr = GET_PIXEL(frame, x + 1, y - 1);
|
|
|
|
inverse_predict[m](p, p_l, p_tl, p_t, p_tr);
|
|
|
|
dec[0] += p[0];
|
|
dec[1] += p[1];
|
|
dec[2] += p[2];
|
|
dec[3] += p[3];
|
|
}
|
|
|
|
static int apply_predictor_transform(WebPContext *s)
|
|
{
|
|
ImageContext *img = &s->image[IMAGE_ROLE_ARGB];
|
|
ImageContext *pimg = &s->image[IMAGE_ROLE_PREDICTOR];
|
|
int x, y;
|
|
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
int tx = x >> pimg->size_reduction;
|
|
int ty = y >> pimg->size_reduction;
|
|
enum PredictionMode m = GET_PIXEL_COMP(pimg->frame, tx, ty, 2);
|
|
|
|
if (x == 0) {
|
|
if (y == 0)
|
|
m = PRED_MODE_BLACK;
|
|
else
|
|
m = PRED_MODE_T;
|
|
} else if (y == 0)
|
|
m = PRED_MODE_L;
|
|
|
|
if (m > 13) {
|
|
av_log(s->avctx, AV_LOG_ERROR,
|
|
"invalid predictor mode: %d\n", m);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
inverse_prediction(img->frame, m, x, y);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static av_always_inline uint8_t color_transform_delta(uint8_t color_pred,
|
|
uint8_t color)
|
|
{
|
|
return (int)ff_u8_to_s8(color_pred) * ff_u8_to_s8(color) >> 5;
|
|
}
|
|
|
|
static int apply_color_transform(WebPContext *s)
|
|
{
|
|
ImageContext *img, *cimg;
|
|
int x, y, cx, cy;
|
|
uint8_t *p, *cp;
|
|
|
|
img = &s->image[IMAGE_ROLE_ARGB];
|
|
cimg = &s->image[IMAGE_ROLE_COLOR_TRANSFORM];
|
|
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
cx = x >> cimg->size_reduction;
|
|
cy = y >> cimg->size_reduction;
|
|
cp = GET_PIXEL(cimg->frame, cx, cy);
|
|
p = GET_PIXEL(img->frame, x, y);
|
|
|
|
p[1] += color_transform_delta(cp[3], p[2]);
|
|
p[3] += color_transform_delta(cp[2], p[2]) +
|
|
color_transform_delta(cp[1], p[1]);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int apply_subtract_green_transform(WebPContext *s)
|
|
{
|
|
int x, y;
|
|
ImageContext *img = &s->image[IMAGE_ROLE_ARGB];
|
|
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
uint8_t *p = GET_PIXEL(img->frame, x, y);
|
|
p[1] += p[2];
|
|
p[3] += p[2];
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int apply_color_indexing_transform(WebPContext *s)
|
|
{
|
|
ImageContext *img;
|
|
ImageContext *pal;
|
|
int i, x, y;
|
|
uint8_t *p;
|
|
|
|
img = &s->image[IMAGE_ROLE_ARGB];
|
|
pal = &s->image[IMAGE_ROLE_COLOR_INDEXING];
|
|
|
|
if (pal->size_reduction > 0) {
|
|
GetBitContext gb_g;
|
|
uint8_t *line;
|
|
int pixel_bits = 8 >> pal->size_reduction;
|
|
|
|
line = av_malloc(img->frame->linesize[0]);
|
|
if (!line)
|
|
return AVERROR(ENOMEM);
|
|
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
p = GET_PIXEL(img->frame, 0, y);
|
|
memcpy(line, p, img->frame->linesize[0]);
|
|
init_get_bits(&gb_g, line, img->frame->linesize[0] * 8);
|
|
skip_bits(&gb_g, 16);
|
|
i = 0;
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
p = GET_PIXEL(img->frame, x, y);
|
|
p[2] = get_bits(&gb_g, pixel_bits);
|
|
i++;
|
|
if (i == 1 << pal->size_reduction) {
|
|
skip_bits(&gb_g, 24);
|
|
i = 0;
|
|
}
|
|
}
|
|
}
|
|
av_free(line);
|
|
}
|
|
|
|
for (y = 0; y < img->frame->height; y++) {
|
|
for (x = 0; x < img->frame->width; x++) {
|
|
p = GET_PIXEL(img->frame, x, y);
|
|
i = p[2];
|
|
if (i >= pal->frame->width) {
|
|
AV_WB32(p, 0xFF000000);
|
|
} else {
|
|
const uint8_t *pi = GET_PIXEL(pal->frame, i, 0);
|
|
AV_COPY32(p, pi);
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int vp8_lossless_decode_frame(AVCodecContext *avctx, AVFrame *p,
|
|
int *got_frame, uint8_t *data_start,
|
|
unsigned int data_size, int is_alpha_chunk)
|
|
{
|
|
WebPContext *s = avctx->priv_data;
|
|
int w, h, ret, i;
|
|
|
|
if (!is_alpha_chunk) {
|
|
s->lossless = 1;
|
|
avctx->pix_fmt = AV_PIX_FMT_ARGB;
|
|
}
|
|
|
|
ret = init_get_bits(&s->gb, data_start, data_size * 8);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (!is_alpha_chunk) {
|
|
if (get_bits(&s->gb, 8) != 0x2F) {
|
|
av_log(avctx, AV_LOG_ERROR, "Invalid WebP Lossless signature\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
w = get_bits(&s->gb, 14) + 1;
|
|
h = get_bits(&s->gb, 14) + 1;
|
|
if (s->width && s->width != w) {
|
|
av_log(avctx, AV_LOG_WARNING, "Width mismatch. %d != %d\n",
|
|
s->width, w);
|
|
}
|
|
s->width = w;
|
|
if (s->height && s->height != h) {
|
|
av_log(avctx, AV_LOG_WARNING, "Height mismatch. %d != %d\n",
|
|
s->width, w);
|
|
}
|
|
s->height = h;
|
|
|
|
ret = ff_set_dimensions(avctx, s->width, s->height);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
s->has_alpha = get_bits1(&s->gb);
|
|
|
|
if (get_bits(&s->gb, 3) != 0x0) {
|
|
av_log(avctx, AV_LOG_ERROR, "Invalid WebP Lossless version\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
} else {
|
|
if (!s->width || !s->height)
|
|
return AVERROR_BUG;
|
|
w = s->width;
|
|
h = s->height;
|
|
}
|
|
|
|
/* parse transformations */
|
|
s->nb_transforms = 0;
|
|
s->reduced_width = 0;
|
|
while (get_bits1(&s->gb)) {
|
|
enum TransformType transform = get_bits(&s->gb, 2);
|
|
s->transforms[s->nb_transforms++] = transform;
|
|
switch (transform) {
|
|
case PREDICTOR_TRANSFORM:
|
|
ret = parse_transform_predictor(s);
|
|
break;
|
|
case COLOR_TRANSFORM:
|
|
ret = parse_transform_color(s);
|
|
break;
|
|
case COLOR_INDEXING_TRANSFORM:
|
|
ret = parse_transform_color_indexing(s);
|
|
break;
|
|
}
|
|
if (ret < 0)
|
|
goto free_and_return;
|
|
}
|
|
|
|
/* decode primary image */
|
|
s->image[IMAGE_ROLE_ARGB].frame = p;
|
|
if (is_alpha_chunk)
|
|
s->image[IMAGE_ROLE_ARGB].is_alpha_primary = 1;
|
|
ret = decode_entropy_coded_image(s, IMAGE_ROLE_ARGB, w, h);
|
|
if (ret < 0)
|
|
goto free_and_return;
|
|
|
|
/* apply transformations */
|
|
for (i = s->nb_transforms - 1; i >= 0; i--) {
|
|
switch (s->transforms[i]) {
|
|
case PREDICTOR_TRANSFORM:
|
|
ret = apply_predictor_transform(s);
|
|
break;
|
|
case COLOR_TRANSFORM:
|
|
ret = apply_color_transform(s);
|
|
break;
|
|
case SUBTRACT_GREEN:
|
|
ret = apply_subtract_green_transform(s);
|
|
break;
|
|
case COLOR_INDEXING_TRANSFORM:
|
|
ret = apply_color_indexing_transform(s);
|
|
break;
|
|
}
|
|
if (ret < 0)
|
|
goto free_and_return;
|
|
}
|
|
|
|
*got_frame = 1;
|
|
p->pict_type = AV_PICTURE_TYPE_I;
|
|
p->key_frame = 1;
|
|
ret = data_size;
|
|
|
|
free_and_return:
|
|
for (i = 0; i < IMAGE_ROLE_NB; i++)
|
|
image_ctx_free(&s->image[i]);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void alpha_inverse_prediction(AVFrame *frame, enum AlphaFilter m)
|
|
{
|
|
int x, y, ls;
|
|
uint8_t *dec;
|
|
|
|
ls = frame->linesize[3];
|
|
|
|
/* filter first row using horizontal filter */
|
|
dec = frame->data[3] + 1;
|
|
for (x = 1; x < frame->width; x++, dec++)
|
|
*dec += *(dec - 1);
|
|
|
|
/* filter first column using vertical filter */
|
|
dec = frame->data[3] + ls;
|
|
for (y = 1; y < frame->height; y++, dec += ls)
|
|
*dec += *(dec - ls);
|
|
|
|
/* filter the rest using the specified filter */
|
|
switch (m) {
|
|
case ALPHA_FILTER_HORIZONTAL:
|
|
for (y = 1; y < frame->height; y++) {
|
|
dec = frame->data[3] + y * ls + 1;
|
|
for (x = 1; x < frame->width; x++, dec++)
|
|
*dec += *(dec - 1);
|
|
}
|
|
break;
|
|
case ALPHA_FILTER_VERTICAL:
|
|
for (y = 1; y < frame->height; y++) {
|
|
dec = frame->data[3] + y * ls + 1;
|
|
for (x = 1; x < frame->width; x++, dec++)
|
|
*dec += *(dec - ls);
|
|
}
|
|
break;
|
|
case ALPHA_FILTER_GRADIENT:
|
|
for (y = 1; y < frame->height; y++) {
|
|
dec = frame->data[3] + y * ls + 1;
|
|
for (x = 1; x < frame->width; x++, dec++)
|
|
dec[0] += av_clip_uint8(*(dec - 1) + *(dec - ls) - *(dec - ls - 1));
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int vp8_lossy_decode_alpha(AVCodecContext *avctx, AVFrame *p,
|
|
uint8_t *data_start,
|
|
unsigned int data_size)
|
|
{
|
|
WebPContext *s = avctx->priv_data;
|
|
int x, y, ret;
|
|
|
|
if (s->alpha_compression == ALPHA_COMPRESSION_NONE) {
|
|
GetByteContext gb;
|
|
|
|
bytestream2_init(&gb, data_start, data_size);
|
|
for (y = 0; y < s->height; y++)
|
|
bytestream2_get_buffer(&gb, p->data[3] + p->linesize[3] * y,
|
|
s->width);
|
|
} else if (s->alpha_compression == ALPHA_COMPRESSION_VP8L) {
|
|
uint8_t *ap, *pp;
|
|
int alpha_got_frame = 0;
|
|
|
|
s->alpha_frame = av_frame_alloc();
|
|
if (!s->alpha_frame)
|
|
return AVERROR(ENOMEM);
|
|
|
|
ret = vp8_lossless_decode_frame(avctx, s->alpha_frame, &alpha_got_frame,
|
|
data_start, data_size, 1);
|
|
if (ret < 0) {
|
|
av_frame_free(&s->alpha_frame);
|
|
return ret;
|
|
}
|
|
if (!alpha_got_frame) {
|
|
av_frame_free(&s->alpha_frame);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
/* copy green component of alpha image to alpha plane of primary image */
|
|
for (y = 0; y < s->height; y++) {
|
|
ap = GET_PIXEL(s->alpha_frame, 0, y) + 2;
|
|
pp = p->data[3] + p->linesize[3] * y;
|
|
for (x = 0; x < s->width; x++) {
|
|
*pp = *ap;
|
|
pp++;
|
|
ap += 4;
|
|
}
|
|
}
|
|
av_frame_free(&s->alpha_frame);
|
|
}
|
|
|
|
/* apply alpha filtering */
|
|
if (s->alpha_filter)
|
|
alpha_inverse_prediction(p, s->alpha_filter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int vp8_lossy_decode_frame(AVCodecContext *avctx, AVFrame *p,
|
|
int *got_frame, uint8_t *data_start,
|
|
unsigned int data_size)
|
|
{
|
|
WebPContext *s = avctx->priv_data;
|
|
AVPacket pkt;
|
|
int ret;
|
|
|
|
if (!s->initialized) {
|
|
ff_vp8_decode_init(avctx);
|
|
s->initialized = 1;
|
|
if (s->has_alpha)
|
|
avctx->pix_fmt = AV_PIX_FMT_YUVA420P;
|
|
}
|
|
s->lossless = 0;
|
|
|
|
if (data_size > INT_MAX) {
|
|
av_log(avctx, AV_LOG_ERROR, "unsupported chunk size\n");
|
|
return AVERROR_PATCHWELCOME;
|
|
}
|
|
|
|
av_init_packet(&pkt);
|
|
pkt.data = data_start;
|
|
pkt.size = data_size;
|
|
|
|
ret = ff_vp8_decode_frame(avctx, p, got_frame, &pkt);
|
|
if (s->has_alpha) {
|
|
ret = vp8_lossy_decode_alpha(avctx, p, s->alpha_data,
|
|
s->alpha_data_size);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int webp_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
|
|
AVPacket *avpkt)
|
|
{
|
|
AVFrame * const p = data;
|
|
WebPContext *s = avctx->priv_data;
|
|
GetByteContext gb;
|
|
int ret;
|
|
uint32_t chunk_type, chunk_size;
|
|
int vp8x_flags = 0;
|
|
|
|
s->avctx = avctx;
|
|
s->width = 0;
|
|
s->height = 0;
|
|
*got_frame = 0;
|
|
s->has_alpha = 0;
|
|
s->has_exif = 0;
|
|
bytestream2_init(&gb, avpkt->data, avpkt->size);
|
|
|
|
if (bytestream2_get_bytes_left(&gb) < 12)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (bytestream2_get_le32(&gb) != MKTAG('R', 'I', 'F', 'F')) {
|
|
av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
chunk_size = bytestream2_get_le32(&gb);
|
|
if (bytestream2_get_bytes_left(&gb) < chunk_size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (bytestream2_get_le32(&gb) != MKTAG('W', 'E', 'B', 'P')) {
|
|
av_log(avctx, AV_LOG_ERROR, "missing WEBP tag\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
av_dict_free(&s->exif_metadata);
|
|
while (bytestream2_get_bytes_left(&gb) > 0) {
|
|
char chunk_str[5] = { 0 };
|
|
|
|
chunk_type = bytestream2_get_le32(&gb);
|
|
chunk_size = bytestream2_get_le32(&gb);
|
|
if (chunk_size == UINT32_MAX)
|
|
return AVERROR_INVALIDDATA;
|
|
chunk_size += chunk_size & 1;
|
|
|
|
if (bytestream2_get_bytes_left(&gb) < chunk_size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
switch (chunk_type) {
|
|
case MKTAG('V', 'P', '8', ' '):
|
|
if (!*got_frame) {
|
|
ret = vp8_lossy_decode_frame(avctx, p, got_frame,
|
|
avpkt->data + bytestream2_tell(&gb),
|
|
chunk_size);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
bytestream2_skip(&gb, chunk_size);
|
|
break;
|
|
case MKTAG('V', 'P', '8', 'L'):
|
|
if (!*got_frame) {
|
|
ret = vp8_lossless_decode_frame(avctx, p, got_frame,
|
|
avpkt->data + bytestream2_tell(&gb),
|
|
chunk_size, 0);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
bytestream2_skip(&gb, chunk_size);
|
|
break;
|
|
case MKTAG('V', 'P', '8', 'X'):
|
|
vp8x_flags = bytestream2_get_byte(&gb);
|
|
bytestream2_skip(&gb, 3);
|
|
s->width = bytestream2_get_le24(&gb) + 1;
|
|
s->height = bytestream2_get_le24(&gb) + 1;
|
|
ret = av_image_check_size(s->width, s->height, 0, avctx);
|
|
if (ret < 0)
|
|
return ret;
|
|
break;
|
|
case MKTAG('A', 'L', 'P', 'H'): {
|
|
int alpha_header, filter_m, compression;
|
|
|
|
if (!(vp8x_flags & VP8X_FLAG_ALPHA)) {
|
|
av_log(avctx, AV_LOG_WARNING,
|
|
"ALPHA chunk present, but alpha bit not set in the "
|
|
"VP8X header\n");
|
|
}
|
|
if (chunk_size == 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "invalid ALPHA chunk size\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
alpha_header = bytestream2_get_byte(&gb);
|
|
s->alpha_data = avpkt->data + bytestream2_tell(&gb);
|
|
s->alpha_data_size = chunk_size - 1;
|
|
bytestream2_skip(&gb, s->alpha_data_size);
|
|
|
|
filter_m = (alpha_header >> 2) & 0x03;
|
|
compression = alpha_header & 0x03;
|
|
|
|
if (compression > ALPHA_COMPRESSION_VP8L) {
|
|
av_log(avctx, AV_LOG_VERBOSE,
|
|
"skipping unsupported ALPHA chunk\n");
|
|
} else {
|
|
s->has_alpha = 1;
|
|
s->alpha_compression = compression;
|
|
s->alpha_filter = filter_m;
|
|
}
|
|
|
|
break;
|
|
}
|
|
case MKTAG('E', 'X', 'I', 'F'): {
|
|
int le, ifd_offset, exif_offset = bytestream2_tell(&gb);
|
|
GetByteContext exif_gb;
|
|
|
|
if (s->has_exif) {
|
|
av_log(avctx, AV_LOG_VERBOSE, "Ignoring extra EXIF chunk\n");
|
|
goto exif_end;
|
|
}
|
|
if (!(vp8x_flags & VP8X_FLAG_EXIF_METADATA))
|
|
av_log(avctx, AV_LOG_WARNING,
|
|
"EXIF chunk present, but Exif bit not set in the "
|
|
"VP8X header\n");
|
|
|
|
s->has_exif = 1;
|
|
bytestream2_init(&exif_gb, avpkt->data + exif_offset,
|
|
avpkt->size - exif_offset);
|
|
if (ff_tdecode_header(&exif_gb, &le, &ifd_offset) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "invalid TIFF header "
|
|
"in Exif data\n");
|
|
goto exif_end;
|
|
}
|
|
|
|
bytestream2_seek(&exif_gb, ifd_offset, SEEK_SET);
|
|
if (avpriv_exif_decode_ifd(avctx, &exif_gb, le, 0, &s->exif_metadata) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "error decoding Exif data\n");
|
|
goto exif_end;
|
|
}
|
|
|
|
av_dict_copy(avpriv_frame_get_metadatap(data), s->exif_metadata, 0);
|
|
|
|
exif_end:
|
|
av_dict_free(&s->exif_metadata);
|
|
bytestream2_skip(&gb, chunk_size);
|
|
break;
|
|
}
|
|
case MKTAG('I', 'C', 'C', 'P'):
|
|
case MKTAG('A', 'N', 'I', 'M'):
|
|
case MKTAG('A', 'N', 'M', 'F'):
|
|
case MKTAG('X', 'M', 'P', ' '):
|
|
AV_WL32(chunk_str, chunk_type);
|
|
av_log(avctx, AV_LOG_VERBOSE, "skipping unsupported chunk: %s\n",
|
|
chunk_str);
|
|
bytestream2_skip(&gb, chunk_size);
|
|
break;
|
|
default:
|
|
AV_WL32(chunk_str, chunk_type);
|
|
av_log(avctx, AV_LOG_VERBOSE, "skipping unknown chunk: %s\n",
|
|
chunk_str);
|
|
bytestream2_skip(&gb, chunk_size);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!*got_frame) {
|
|
av_log(avctx, AV_LOG_ERROR, "image data not found\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
return avpkt->size;
|
|
}
|
|
|
|
static av_cold int webp_decode_close(AVCodecContext *avctx)
|
|
{
|
|
WebPContext *s = avctx->priv_data;
|
|
|
|
if (s->initialized)
|
|
return ff_vp8_decode_free(avctx);
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVCodec ff_webp_decoder = {
|
|
.name = "webp",
|
|
.long_name = NULL_IF_CONFIG_SMALL("WebP image"),
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = AV_CODEC_ID_WEBP,
|
|
.priv_data_size = sizeof(WebPContext),
|
|
.decode = webp_decode_frame,
|
|
.close = webp_decode_close,
|
|
.capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
|
|
};
|