aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJustin Ruggles <justin.ruggles@gmail.com>2013-04-16 22:42:26 +0530
committerJustin Ruggles <justin.ruggles@gmail.com>2013-09-18 14:10:05 -0400
commitc4bfa098072ba338d83555d6e2199f7e1e64ffff (patch)
treeea94623c757978836d8d1ded2ef7b1599f20b5f9
parent9ae53c5860e17d087642d27b00dade071970a2e7 (diff)
downloadffmpeg-c4bfa098072ba338d83555d6e2199f7e1e64ffff.tar.gz
Add a WebP decoder
Container and lossy decoding by Aneesh Dogra <aneesh@sugarlabs.org> Lossless decoding by Justin Ruggles <justin.ruggles@gmail.com>
-rw-r--r--Changelog1
-rwxr-xr-xconfigure1
-rw-r--r--doc/general.texi2
-rw-r--r--libavcodec/Makefile1
-rw-r--r--libavcodec/allcodecs.c1
-rw-r--r--libavcodec/avcodec.h1
-rw-r--r--libavcodec/codec_desc.c8
-rw-r--r--libavcodec/version.h2
-rw-r--r--libavcodec/vp8.c18
-rw-r--r--libavcodec/vp8.h7
-rw-r--r--libavcodec/webp.c1455
-rw-r--r--libavformat/img2.c1
12 files changed, 1488 insertions, 10 deletions
diff --git a/Changelog b/Changelog
index 7e210a71c1..501e1c5316 100644
--- a/Changelog
+++ b/Changelog
@@ -33,6 +33,7 @@ version 10:
- avconv -t option can now be used for inputs, to limit the duration of
data read from an input file
- incomplete Voxware MetaSound decoder
+- WebP decoder
version 9:
diff --git a/configure b/configure
index b95e4acfa9..1e195d57e2 100755
--- a/configure
+++ b/configure
@@ -1692,6 +1692,7 @@ vp6_decoder_select="h264chroma hpeldsp huffman videodsp vp3dsp"
vp6a_decoder_select="vp6_decoder"
vp6f_decoder_select="vp6_decoder"
vp8_decoder_select="h264pred videodsp"
+webp_decoder_select="vp8_decoder"
wmapro_decoder_select="mdct sinewin"
wmav1_decoder_select="mdct sinewin"
wmav1_encoder_select="mdct sinewin"
diff --git a/doc/general.texi b/doc/general.texi
index bd0a7fb0e8..aeda8ea92b 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -412,6 +412,8 @@ following image formats are supported:
@tab YUV, JPEG and some extension is not supported yet.
@item Truevision Targa @tab X @tab X
@tab Targa (.TGA) image format
+@item WebP @tab @tab X
+ @tab WebP image format
@item XBM @tab X @tab
@tab X BitMap image format
@item XWD @tab X @tab X
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index bb4f960356..b10526bb43 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -390,6 +390,7 @@ OBJS-$(CONFIG_VP6_DECODER) += vp6.o vp56.o vp56data.o vp56dsp.o \
OBJS-$(CONFIG_VP8_DECODER) += vp8.o vp8dsp.o vp56rac.o
OBJS-$(CONFIG_VQA_DECODER) += vqavideo.o
OBJS-$(CONFIG_WAVPACK_DECODER) += wavpack.o
+OBJS-$(CONFIG_WEBP_DECODER) += webp.o
OBJS-$(CONFIG_WMALOSSLESS_DECODER) += wmalosslessdec.o wma_common.o
OBJS-$(CONFIG_WMAPRO_DECODER) += wmaprodec.o wma.o wma_common.o
OBJS-$(CONFIG_WMAV1_DECODER) += wmadec.o wma.o wma_common.o aactab.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index d4531f2dff..f827ca3a31 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -253,6 +253,7 @@ void avcodec_register_all(void)
REGISTER_DECODER(VP6F, vp6f);
REGISTER_DECODER(VP8, vp8);
REGISTER_DECODER(VQA, vqa);
+ REGISTER_DECODER(WEBP, webp);
REGISTER_ENCDEC (WMV1, wmv1);
REGISTER_ENCDEC (WMV2, wmv2);
REGISTER_DECODER(WMV3, wmv3);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 2a39b433c3..b894ee8ecc 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -273,6 +273,7 @@ enum AVCodecID {
AV_CODEC_ID_AIC,
AV_CODEC_ID_ESCAPE130,
AV_CODEC_ID_G2M,
+ AV_CODEC_ID_WEBP,
/* various PCM "codecs" */
AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 90e489175c..abab828ec6 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1228,6 +1228,14 @@ static const AVCodecDescriptor codec_descriptors[] = {
.long_name = NULL_IF_CONFIG_SMALL("Go2Meeting"),
.props = AV_CODEC_PROP_LOSSY,
},
+ {
+ .id = AV_CODEC_ID_WEBP,
+ .type = AVMEDIA_TYPE_VIDEO,
+ .name = "webp",
+ .long_name = NULL_IF_CONFIG_SMALL("WebP"),
+ .props = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY |
+ AV_CODEC_PROP_LOSSLESS,
+ },
/* various PCM "codecs" */
{
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 980c5c5240..9775a650e4 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -27,7 +27,7 @@
*/
#define LIBAVCODEC_VERSION_MAJOR 55
-#define LIBAVCODEC_VERSION_MINOR 18
+#define LIBAVCODEC_VERSION_MINOR 19
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
diff --git a/libavcodec/vp8.c b/libavcodec/vp8.c
index 17b79f5fc4..3c60aa3409 100644
--- a/libavcodec/vp8.c
+++ b/libavcodec/vp8.c
@@ -1853,8 +1853,8 @@ static int vp8_decode_mb_row_sliced(AVCodecContext *avctx, void *tdata,
return 0;
}
-static int vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
- AVPacket *avpkt)
+int ff_vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+ AVPacket *avpkt)
{
VP8Context *s = avctx->priv_data;
int ret, i, referenced, num_jobs;
@@ -2010,7 +2010,7 @@ err:
return ret;
}
-static av_cold int vp8_decode_free(AVCodecContext *avctx)
+av_cold int ff_vp8_decode_free(AVCodecContext *avctx)
{
VP8Context *s = avctx->priv_data;
int i;
@@ -2033,7 +2033,7 @@ static av_cold int vp8_init_frames(VP8Context *s)
return 0;
}
-static av_cold int vp8_decode_init(AVCodecContext *avctx)
+av_cold int ff_vp8_decode_init(AVCodecContext *avctx)
{
VP8Context *s = avctx->priv_data;
int ret;
@@ -2047,7 +2047,7 @@ static av_cold int vp8_decode_init(AVCodecContext *avctx)
ff_vp8dsp_init(&s->vp8dsp);
if ((ret = vp8_init_frames(s)) < 0) {
- vp8_decode_free(avctx);
+ ff_vp8_decode_free(avctx);
return ret;
}
@@ -2062,7 +2062,7 @@ static av_cold int vp8_decode_init_thread_copy(AVCodecContext *avctx)
s->avctx = avctx;
if ((ret = vp8_init_frames(s)) < 0) {
- vp8_decode_free(avctx);
+ ff_vp8_decode_free(avctx);
return ret;
}
@@ -2110,9 +2110,9 @@ AVCodec ff_vp8_decoder = {
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_VP8,
.priv_data_size = sizeof(VP8Context),
- .init = vp8_decode_init,
- .close = vp8_decode_free,
- .decode = vp8_decode_frame,
+ .init = ff_vp8_decode_init,
+ .close = ff_vp8_decode_free,
+ .decode = ff_vp8_decode_frame,
.capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS | CODEC_CAP_SLICE_THREADS,
.flush = vp8_decode_flush,
.long_name = NULL_IF_CONFIG_SMALL("On2 VP8"),
diff --git a/libavcodec/vp8.h b/libavcodec/vp8.h
index 80f555f404..6555629806 100644
--- a/libavcodec/vp8.h
+++ b/libavcodec/vp8.h
@@ -269,4 +269,11 @@ typedef struct VP8Context {
int mb_layout;
} VP8Context;
+int ff_vp8_decode_init(AVCodecContext *avctx);
+
+int ff_vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+ AVPacket *avpkt);
+
+int ff_vp8_decode_free(AVCodecContext *avctx);
+
#endif /* AVCODEC_VP8_H */
diff --git a/libavcodec/webp.c b/libavcodec/webp.c
new file mode 100644
index 0000000000..8ad24f8fb7
--- /dev/null
+++ b/libavcodec/webp.c
@@ -0,0 +1,1455 @@
+/*
+ * WebP (.webp) image decoder
+ * Copyright (c) 2013 Aneesh Dogra <aneesh@sugarlabs.org>
+ * Copyright (c) 2013 Justin Ruggles <justin.ruggles@gmail.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * WebP image decoder
+ *
+ * @author Aneesh Dogra <aneesh@sugarlabs.org>
+ * Container and Lossy decoding
+ *
+ * @author Justin Ruggles <justin.ruggles@gmail.com>
+ * Lossless decoder
+ * Compressed alpha for lossy
+ *
+ * Unimplemented:
+ * - Animation
+ * - ICC profile
+ * - Exif and XMP metadata
+ */
+
+#define BITSTREAM_READER_LE
+#include "libavutil/imgutils.h"
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+#include "get_bits.h"
+#include "thread.h"
+#include "vp8.h"
+
+#define VP8X_FLAG_ANIMATION 0x02
+#define VP8X_FLAG_XMP_METADATA 0x04
+#define VP8X_FLAG_EXIF_METADATA 0x08
+#define VP8X_FLAG_ALPHA 0x10
+#define VP8X_FLAG_ICC 0x20
+
+#define MAX_PALETTE_SIZE 256
+#define MAX_CACHE_BITS 11
+#define NUM_CODE_LENGTH_CODES 19
+#define HUFFMAN_CODES_PER_META_CODE 5
+#define NUM_LITERAL_CODES 256
+#define NUM_LENGTH_CODES 24
+#define NUM_DISTANCE_CODES 40
+#define NUM_SHORT_DISTANCES 120
+#define MAX_HUFFMAN_CODE_LENGTH 15
+
+static const uint16_t alphabet_sizes[HUFFMAN_CODES_PER_META_CODE] = {
+ NUM_LITERAL_CODES + NUM_LENGTH_CODES,
+ NUM_LITERAL_CODES, NUM_LITERAL_CODES, NUM_LITERAL_CODES,
+ NUM_DISTANCE_CODES
+};
+
+static const uint8_t code_length_code_order[NUM_CODE_LENGTH_CODES] = {
+ 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+};
+
+static const int8_t lz77_distance_offsets[NUM_SHORT_DISTANCES][2] = {
+ { 0, 1 }, { 1, 0 }, { 1, 1 }, { -1, 1 }, { 0, 2 }, { 2, 0 }, { 1, 2 }, { -1, 2 },
+ { 2, 1 }, { -2, 1 }, { 2, 2 }, { -2, 2 }, { 0, 3 }, { 3, 0 }, { 1, 3 }, { -1, 3 },
+ { 3, 1 }, { -3, 1 }, { 2, 3 }, { -2, 3 }, { 3, 2 }, { -3, 2 }, { 0, 4 }, { 4, 0 },
+ { 1, 4 }, { -1, 4 }, { 4, 1 }, { -4, 1 }, { 3, 3 }, { -3, 3 }, { 2, 4 }, { -2, 4 },
+ { 4, 2 }, { -4, 2 }, { 0, 5 }, { 3, 4 }, { -3, 4 }, { 4, 3 }, { -4, 3 }, { 5, 0 },
+ { 1, 5 }, { -1, 5 }, { 5, 1 }, { -5, 1 }, { 2, 5 }, { -2, 5 }, { 5, 2 }, { -5, 2 },
+ { 4, 4 }, { -4, 4 }, { 3, 5 }, { -3, 5 }, { 5, 3 }, { -5, 3 }, { 0, 6 }, { 6, 0 },
+ { 1, 6 }, { -1, 6 }, { 6, 1 }, { -6, 1 }, { 2, 6 }, { -2, 6 }, { 6, 2 }, { -6, 2 },
+ { 4, 5 }, { -4, 5 }, { 5, 4 }, { -5, 4 }, { 3, 6 }, { -3, 6 }, { 6, 3 }, { -6, 3 },
+ { 0, 7 }, { 7, 0 }, { 1, 7 }, { -1, 7 }, { 5, 5 }, { -5, 5 }, { 7, 1 }, { -7, 1 },
+ { 4, 6 }, { -4, 6 }, { 6, 4 }, { -6, 4 }, { 2, 7 }, { -2, 7 }, { 7, 2 }, { -7, 2 },
+ { 3, 7 }, { -3, 7 }, { 7, 3 }, { -7, 3 }, { 5, 6 }, { -5, 6 }, { 6, 5 }, { -6, 5 },
+ { 8, 0 }, { 4, 7 }, { -4, 7 }, { 7, 4 }, { -7, 4 }, { 8, 1 }, { 8, 2 }, { 6, 6 },
+ { -6, 6 }, { 8, 3 }, { 5, 7 }, { -5, 7 }, { 7, 5 }, { -7, 5 }, { 8, 4 }, { 6, 7 },
+ { -6, 7 }, { 7, 6 }, { -7, 6 }, { 8, 5 }, { 7, 7 }, { -7, 7 }, { 8, 6 }, { 8, 7 }
+};
+
+enum AlphaCompression {
+ ALPHA_COMPRESSION_NONE,
+ ALPHA_COMPRESSION_VP8L,
+};
+
+enum AlphaFilter {
+ ALPHA_FILTER_NONE,
+ ALPHA_FILTER_HORIZONTAL,
+ ALPHA_FILTER_VERTICAL,
+ ALPHA_FILTER_GRADIENT,
+};
+
+enum TransformType {
+ PREDICTOR_TRANSFORM = 0,
+ COLOR_TRANSFORM = 1,
+ SUBTRACT_GREEN = 2,
+ COLOR_INDEXING_TRANSFORM = 3,
+};
+
+enum PredictionMode {
+ PRED_MODE_BLACK,
+ PRED_MODE_L,
+ PRED_MODE_T,
+ PRED_MODE_TR,
+ PRED_MODE_TL,
+ PRED_MODE_AVG_T_AVG_L_TR,
+ PRED_MODE_AVG_L_TL,
+ PRED_MODE_AVG_L_T,
+ PRED_MODE_AVG_TL_T,
+ PRED_MODE_AVG_T_TR,
+ PRED_MODE_AVG_AVG_L_TL_AVG_T_TR,
+ PRED_MODE_SELECT,
+ PRED_MODE_ADD_SUBTRACT_FULL,
+ PRED_MODE_ADD_SUBTRACT_HALF,
+};
+
+enum HuffmanIndex {
+ HUFF_IDX_GREEN = 0,
+ HUFF_IDX_RED = 1,
+ HUFF_IDX_BLUE = 2,
+ HUFF_IDX_ALPHA = 3,
+ HUFF_IDX_DIST = 4
+};
+
+/* The structure of WebP lossless is an optional series of transformation data,
+ * followed by the primary image. The primary image also optionally contains
+ * an entropy group mapping if there are multiple entropy groups. There is a
+ * basic image type called an "entropy coded image" that is used for all of
+ * these. The type of each entropy coded image is referred to by the
+ * specification as its role. */
+enum ImageRole {
+ /* Primary Image: Stores the actual pixels of the image. */
+ IMAGE_ROLE_ARGB,
+
+ /* Entropy Image: Defines which Huffman group to use for different areas of
+ * the primary image. */
+ IMAGE_ROLE_ENTROPY,
+
+ /* Predictors: Defines which predictor type to use for different areas of
+ * the primary image. */
+ IMAGE_ROLE_PREDICTOR,
+
+ /* Color Transform Data: Defines the color transformation for different
+ * areas of the primary image. */
+ IMAGE_ROLE_COLOR_TRANSFORM,
+
+ /* Color Index: Stored as an image of height == 1. */
+ IMAGE_ROLE_COLOR_INDEXING,
+
+ IMAGE_ROLE_NB,
+};
+
+typedef struct HuffReader {
+ VLC vlc; /* Huffman decoder context */
+ int simple; /* whether to use simple mode */
+ int nb_symbols; /* number of coded symbols */
+ uint16_t simple_symbols[2]; /* symbols for simple mode */
+} HuffReader;
+
+typedef struct ImageContext {
+ enum ImageRole role; /* role of this image */
+ AVFrame *frame; /* AVFrame for data */
+ int color_cache_bits; /* color cache size, log2 */
+ uint32_t *color_cache; /* color cache data */
+ int nb_huffman_groups; /* number of huffman groups */
+ HuffReader *huffman_groups; /* reader for each huffman group */
+ int size_reduction; /* relative size compared to primary image, log2 */
+ int is_alpha_primary;
+} ImageContext;
+
+typedef struct WebPContext {
+ VP8Context v; /* VP8 Context used for lossy decoding */
+ GetBitContext gb; /* bitstream reader for main image chunk */
+ AVFrame *alpha_frame; /* AVFrame for alpha data decompressed from VP8L */
+ AVCodecContext *avctx; /* parent AVCodecContext */
+ int initialized; /* set once the VP8 context is initialized */
+ int has_alpha; /* has a separate alpha chunk */
+ enum AlphaCompression alpha_compression; /* compression type for alpha chunk */
+ enum AlphaFilter alpha_filter; /* filtering method for alpha chunk */
+ uint8_t *alpha_data; /* alpha chunk data */
+ int alpha_data_size; /* alpha chunk data size */
+ int width; /* image width */
+ int height; /* image height */
+ int lossless; /* indicates lossless or lossy */
+
+ int nb_transforms; /* number of transforms */
+ enum TransformType transforms[4]; /* transformations used in the image, in order */
+ int reduced_width; /* reduced width for index image, if applicable */
+ int nb_huffman_groups; /* number of huffman groups in the primary image */
+ ImageContext image[IMAGE_ROLE_NB]; /* image context for each role */
+} WebPContext;
+
+#define GET_PIXEL(frame, x, y) \
+ ((frame)->data[0] + (y) * frame->linesize[0] + 4 * (x))
+
+#define GET_PIXEL_COMP(frame, x, y, c) \
+ (*((frame)->data[0] + (y) * frame->linesize[0] + 4 * (x) + c))
+
+static void image_ctx_free(ImageContext *img)
+{
+ int i, j;
+
+ av_free(img->color_cache);
+ if (img->role != IMAGE_ROLE_ARGB && !img->is_alpha_primary)
+ av_frame_free(&img->frame);
+ if (img->huffman_groups) {
+ for (i = 0; i < img->nb_huffman_groups; i++) {
+ for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; j++)
+ ff_free_vlc(&img->huffman_groups[i * HUFFMAN_CODES_PER_META_CODE + j].vlc);
+ }
+ av_free(img->huffman_groups);
+ }
+ memset(img, 0, sizeof(*img));
+}
+
+
+/* Differs from get_vlc2() in the following ways:
+ * - codes are bit-reversed
+ * - assumes 8-bit table to make reversal simpler
+ * - assumes max depth of 2 since the max code length for WebP is 15
+ */
+static av_always_inline int webp_get_vlc(GetBitContext *gb, VLC_TYPE (*table)[2])
+{
+ int n, nb_bits;
+ unsigned int index;
+ int code;
+
+ OPEN_READER(re, gb);
+ UPDATE_CACHE(re, gb);
+
+ index = SHOW_UBITS(re, gb, 8);
+ index = ff_reverse[index];
+ code = table[index][0];
+ n = table[index][1];
+
+ if (n < 0) {
+ LAST_SKIP_BITS(re, gb, 8);
+ UPDATE_CACHE(re, gb);
+
+ nb_bits = -n;
+
+ index = SHOW_UBITS(re, gb, nb_bits);
+ index = (ff_reverse[index] >> (8 - nb_bits)) + code;
+ code = table[index][0];
+ n = table[index][1];
+ }
+ SKIP_BITS(re, gb, n);
+
+ CLOSE_READER(re, gb);
+
+ return code;
+}
+
+static int huff_reader_get_symbol(HuffReader *r, GetBitContext *gb)
+{
+ if (r->simple) {
+ if (r->nb_symbols == 1)
+ return r->simple_symbols[0];
+ else
+ return r->simple_symbols[get_bits1(gb)];
+ } else
+ return webp_get_vlc(gb, r->vlc.table);
+}
+
+static int huff_reader_build_canonical(HuffReader *r, int *code_lengths,
+ int alphabet_size)
+{
+ int len, sym, code, ret;
+ int max_code_length = 0;
+ uint16_t *codes;
+
+ for (sym = 0; sym < alphabet_size; sym++)
+ max_code_length = FFMAX(max_code_length, code_lengths[sym]);
+
+ if (max_code_length == 0 || max_code_length > MAX_HUFFMAN_CODE_LENGTH)
+ return AVERROR(EINVAL);
+
+ codes = av_malloc(alphabet_size * sizeof(*codes));
+ if (!codes)
+ return AVERROR(ENOMEM);
+
+ code = 0;
+ r->nb_symbols = 0;
+ for (len = 1; len <= max_code_length; len++) {
+ for (sym = 0; sym < alphabet_size; sym++) {
+ if (code_lengths[sym] != len)
+ continue;
+ codes[sym] = code++;
+ r->nb_symbols++;
+ }
+ code <<= 1;
+ }
+ if (!r->nb_symbols) {
+ av_free(codes);
+ return AVERROR_INVALIDDATA;
+ }
+
+ ret = init_vlc(&r->vlc, 8, alphabet_size,
+ code_lengths, sizeof(*code_lengths), sizeof(*code_lengths),
+ codes, sizeof(*codes), sizeof(*codes), 0);
+ if (ret < 0) {
+ av_free(codes);
+ return ret;
+ }
+ r->simple = 0;
+
+ av_free(codes);
+ return 0;
+}
+
+static void read_huffman_code_simple(WebPContext *s, HuffReader *hc)
+{
+ hc->nb_symbols = get_bits1(&s->gb) + 1;
+
+ if (get_bits1(&s->gb))
+ hc->simple_symbols[0] = get_bits(&s->gb, 8);
+ else
+ hc->simple_symbols[0] = get_bits1(&s->gb);
+
+ if (hc->nb_symbols == 2)
+ hc->simple_symbols[1] = get_bits(&s->gb, 8);
+
+ hc->simple = 1;
+}
+
+static int read_huffman_code_normal(WebPContext *s, HuffReader *hc,
+ int alphabet_size)
+{
+ HuffReader code_len_hc = { { 0 }, 0, 0, { 0 } };
+ int *code_lengths = NULL;
+ int code_length_code_lengths[NUM_CODE_LENGTH_CODES] = { 0 };
+ int i, symbol, max_symbol, prev_code_len, ret;
+ int num_codes = 4 + get_bits(&s->gb, 4);
+
+ if (num_codes > NUM_CODE_LENGTH_CODES)
+ return AVERROR_INVALIDDATA;
+
+ for (i = 0; i < num_codes; i++)
+ code_length_code_lengths[code_length_code_order[i]] = get_bits(&s->gb, 3);
+
+ ret = huff_reader_build_canonical(&code_len_hc, code_length_code_lengths,
+ NUM_CODE_LENGTH_CODES);
+ if (ret < 0)
+ goto finish;
+
+ code_lengths = av_mallocz_array(alphabet_size, sizeof(*code_lengths));
+ if (!code_lengths) {
+ ret = AVERROR(ENOMEM);
+ goto finish;
+ }
+
+ if (get_bits1(&s->gb)) {
+ int bits = 2 + 2 * get_bits(&s->gb, 3);
+ max_symbol = 2 + get_bits(&s->gb, bits);
+ if (max_symbol > alphabet_size) {
+ av_log(s->avctx, AV_LOG_ERROR, "max symbol %d > alphabet size %d\n",
+ max_symbol, alphabet_size);
+ ret = AVERROR_INVALIDDATA;
+ goto finish;
+ }
+ } else {
+ max_symbol = alphabet_size;
+ }
+
+ prev_code_len = 8;
+ symbol = 0;
+ while (symbol < alphabet_size) {
+ int code_len;
+
+ if (!max_symbol--)
+ break;
+ code_len = huff_reader_get_symbol(&code_len_hc, &s->gb);
+ if (code_len < 16) {
+ /* Code length code [0..15] indicates literal code lengths. */
+ code_lengths[symbol++] = code_len;
+ if (code_len)
+ prev_code_len = code_len;
+ } else {
+ int repeat = 0, length = 0;
+ switch (code_len) {
+ case 16:
+ /* Code 16 repeats the previous non-zero value [3..6] times,
+ * i.e., 3 + ReadBits(2) times. If code 16 is used before a
+ * non-zero value has been emitted, a value of 8 is repeated. */
+ repeat = 3 + get_bits(&s->gb, 2);
+ length = prev_code_len;
+ break;
+ case 17:
+ /* Code 17 emits a streak of zeros [3..10], i.e.,
+ * 3 + ReadBits(3) times. */
+ repeat = 3 + get_bits(&s->gb, 3);
+ break;
+ case 18:
+ /* Code 18 emits a streak of zeros of length [11..138], i.e.,
+ * 11 + ReadBits(7) times. */
+ repeat = 11 + get_bits(&s->gb, 7);
+ break;
+ }
+ if (symbol + repeat > alphabet_size) {
+ av_log(s->avctx, AV_LOG_ERROR,
+ "invalid symbol %d + repeat %d > alphabet size %d\n",
+ symbol, repeat, alphabet_size);
+ ret = AVERROR_INVALIDDATA;
+ goto finish;
+ }
+ while (repeat-- > 0)
+ code_lengths[symbol++] = length;
+ }
+ }
+
+ ret = huff_reader_build_canonical(hc, code_lengths, alphabet_size);
+
+finish:
+ ff_free_vlc(&code_len_hc.vlc);
+ av_free(code_lengths);
+ return ret;
+}
+
+static int decode_entropy_coded_image(WebPContext *s, enum ImageRole role,
+ int w, int h);
+
+#define PARSE_BLOCK_SIZE(w, h) do { \
+ block_bits = get_bits(&s->gb, 3) + 2; \
+ 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 p = GET_PIXEL_COMP(img->frame, x, y, 2);
+ 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;
+ group = GET_PIXEL_COMP(gimg->frame, group_x, group_y, 2);
+ }
+
+ 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, *pi;
+
+ 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_log(s->avctx, AV_LOG_ERROR, "invalid palette index %d\n", i);
+ return AVERROR_INVALIDDATA;
+ }
+ 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 = av_image_check_size(s->width, s->height, 0, avctx);
+ if (ret < 0)
+ return ret;
+ avcodec_set_dimensions(avctx, s->width, s->height);
+
+ 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) {
+ av_frame_free(&p);
+ 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) {
+ av_frame_free(&p);
+ 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;
+ 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;
+ }
+
+ 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('I', 'C', 'C', 'P'):
+ case MKTAG('A', 'N', 'I', 'M'):
+ case MKTAG('A', 'N', 'M', 'F'):
+ case MKTAG('E', 'X', 'I', '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,
+};
diff --git a/libavformat/img2.c b/libavformat/img2.c
index 23176d2c8c..3b49a32391 100644
--- a/libavformat/img2.c
+++ b/libavformat/img2.c
@@ -65,6 +65,7 @@ static const IdStrMap img_tags[] = {
{ AV_CODEC_ID_JPEG2000, "j2k" },
{ AV_CODEC_ID_DPX, "dpx" },
{ AV_CODEC_ID_PICTOR, "pic" },
+ { AV_CODEC_ID_WEBP, "webp" },
{ AV_CODEC_ID_XBM, "xbm" },
{ AV_CODEC_ID_XWD, "xwd" },
{ AV_CODEC_ID_NONE, NULL }