[FFmpeg-devel] [PATCH v12 4/8] libavcodec/webp: add support for animated WebP
thilo.borgmann at mail.de
thilo.borgmann at mail.de
Wed Apr 17 22:20:00 EEST 2024
From: Josef Zlomek <josef at pex.com>
Fixes: 4907
Adds support for decoding of animated WebP.
The WebP decoder adds the animation related features according to the specs:
https://developers.google.com/speed/webp/docs/riff_container#animation
The frames of the animation may be smaller than the image canvas.
Therefore, the frame is decoded to a temporary frame,
then it is blended into the canvas, the canvas is copied to the output frame,
and finally the frame is disposed from the canvas.
The output to AV_PIX_FMT_YUVA420P/AV_PIX_FMT_YUV420P is still supported.
The background color is specified only as BGRA in the WebP file
so it is converted to YUVA if YUV formats are output.
Signed-off-by: Josef Zlomek <josef at pex.com>
---
Changelog | 1 +
libavcodec/codec_desc.c | 3 +-
libavcodec/version.h | 2 +-
libavcodec/webp.c | 710 ++++++++++++++++++++++++++++++++++++----
4 files changed, 653 insertions(+), 63 deletions(-)
diff --git a/Changelog b/Changelog
index 5c8f505211..03ac047cea 100644
--- a/Changelog
+++ b/Changelog
@@ -93,6 +93,7 @@ version 6.1:
- ffprobe XML output schema changed to account for multiple
variable-fields elements within the same parent element
- ffprobe -output_format option added as an alias of -of
+- animated WebP decoder
version 6.0:
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 7dba61dc8b..2873f91479 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1259,8 +1259,7 @@ static const AVCodecDescriptor codec_descriptors[] = {
.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,
+ .props = AV_CODEC_PROP_LOSSY | AV_CODEC_PROP_LOSSLESS,
.mime_types= MT("image/webp"),
},
{
diff --git a/libavcodec/version.h b/libavcodec/version.h
index f0958eee14..3d2de546b3 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -30,7 +30,7 @@
#include "version_major.h"
#define LIBAVCODEC_VERSION_MINOR 5
-#define LIBAVCODEC_VERSION_MICRO 103
+#define LIBAVCODEC_VERSION_MICRO 104
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
LIBAVCODEC_VERSION_MINOR, \
diff --git a/libavcodec/webp.c b/libavcodec/webp.c
index 3075321e86..f882c3e187 100644
--- a/libavcodec/webp.c
+++ b/libavcodec/webp.c
@@ -35,13 +35,16 @@
* Exif metadata
* ICC profile
*
+ * @author Josef Zlomek, Pexeso Inc. <josef at pex.com>
+ * Animation
+ *
* Unimplemented:
- * - Animation
* - XMP metadata
*/
#include "libavutil/imgutils.h"
#include "libavutil/mem.h"
+#include "libavutil/colorspace.h"
#define BITSTREAM_READER_LE
#include "avcodec.h"
@@ -68,6 +71,14 @@
#define NUM_SHORT_DISTANCES 120
#define MAX_HUFFMAN_CODE_LENGTH 15
+#define ANMF_DISPOSAL_METHOD 0x01
+#define ANMF_DISPOSAL_METHOD_UNCHANGED 0x00
+#define ANMF_DISPOSAL_METHOD_BACKGROUND 0x01
+
+#define ANMF_BLENDING_METHOD 0x02
+#define ANMF_BLENDING_METHOD_ALPHA 0x00
+#define ANMF_BLENDING_METHOD_OVERWRITE 0x02
+
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,
@@ -192,6 +203,8 @@ typedef struct ImageContext {
typedef struct WebPContext {
VP8Context v; /* VP8 Context used for lossy decoding */
GetBitContext gb; /* bitstream reader for main image chunk */
+ ThreadFrame canvas_frame; /* ThreadFrame for canvas */
+ AVFrame *frame; /* AVFrame for decoded frame */
AVFrame *alpha_frame; /* AVFrame for alpha data decompressed from VP8L */
AVPacket *pkt; /* AVPacket to be passed to the underlying VP8 decoder */
AVCodecContext *avctx; /* parent AVCodecContext */
@@ -206,7 +219,22 @@ typedef struct WebPContext {
int has_iccp; /* set after an ICCP chunk has been processed */
int width; /* image width */
int height; /* image height */
- int lossless; /* indicates lossless or lossy */
+ int vp8x_flags; /* global flags from VP8X chunk */
+ int canvas_width; /* canvas width */
+ int canvas_height; /* canvas height */
+ int anmf_flags; /* frame flags from ANMF chunk */
+ int pos_x; /* frame position X */
+ int pos_y; /* frame position Y */
+ int prev_anmf_flags; /* previous frame flags from ANMF chunk */
+ int prev_width; /* previous frame width */
+ int prev_height; /* previous frame height */
+ int prev_pos_x; /* previous frame position X */
+ int prev_pos_y; /* previous frame position Y */
+ int await_progress; /* value of progress to wait for */
+ uint8_t background_argb[4]; /* background color in ARGB format */
+ uint8_t background_yuva[4]; /* background color in YUVA format */
+ const uint8_t *background_data[4]; /* "planes" for background color in YUVA format */
+ uint8_t transparent_yuva[4]; /* transparent black in YUVA format */
int nb_transforms; /* number of transforms */
enum TransformType transforms[4]; /* transformations used in the image, in order */
@@ -1091,7 +1119,6 @@ static int vp8_lossless_decode_frame(AVCodecContext *avctx, AVFrame *p,
int w, h, ret, i, used;
if (!is_alpha_chunk) {
- s->lossless = 1;
avctx->pix_fmt = AV_PIX_FMT_ARGB;
}
@@ -1305,9 +1332,10 @@ static int vp8_lossy_decode_frame(AVCodecContext *avctx, AVFrame *p,
s->initialized = 1;
}
avctx->pix_fmt = s->has_alpha ? AV_PIX_FMT_YUVA420P : AV_PIX_FMT_YUV420P;
- s->lossless = 0;
s->avctx_vp8->pix_fmt = avctx->pix_fmt;
+ ff_thread_finish_setup(s->avctx);
+
if (data_size > INT_MAX) {
av_log(avctx, AV_LOG_ERROR, "unsupported chunk size\n");
return AVERROR_PATCHWELCOME;
@@ -1342,7 +1370,6 @@ static int vp8_lossy_decode_frame(AVCodecContext *avctx, AVFrame *p,
}
*got_frame = 1;
- update_canvas_size(avctx, s->avctx_vp8->width, s->avctx_vp8->height);
if (s->has_alpha) {
ret = vp8_lossy_decode_alpha(avctx, p, s->alpha_data,
@@ -1353,40 +1380,21 @@ static int vp8_lossy_decode_frame(AVCodecContext *avctx, AVFrame *p,
return ret;
}
-static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
- int *got_frame, AVPacket *avpkt)
+int init_canvas_frame(WebPContext *s, int format, int key_frame);
+
+static int webp_decode_frame_common(AVCodecContext *avctx, uint8_t *data, int size,
+ int *got_frame, int key_frame, AVFrame *p)
{
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;
- s->has_iccp = 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;
+ bytestream2_init(&gb, data, size);
- if (bytestream2_get_le32(&gb) != MKTAG('W', 'E', 'B', 'P')) {
- av_log(avctx, AV_LOG_ERROR, "missing WEBP tag\n");
- return AVERROR_INVALIDDATA;
- }
+ // reset metadata bit for each packet
+ s->has_exif = 0;
+ s->has_iccp = 0;
while (bytestream2_get_bytes_left(&gb) > 8) {
char chunk_str[5] = { 0 };
@@ -1397,6 +1405,10 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
return AVERROR_INVALIDDATA;
chunk_size += chunk_size & 1;
+ // we need to dive into RIFF chunk
+ if (chunk_type == MKTAG('R', 'I', 'F', 'F'))
+ chunk_size = 4;
+
if (bytestream2_get_bytes_left(&gb) < chunk_size) {
/* we seem to be running out of data, but it could also be that the
bitstream has trailing junk leading to bogus chunk_size. */
@@ -1404,10 +1416,26 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
}
switch (chunk_type) {
+ case MKTAG('R', 'I', 'F', 'F'):
+ if (bytestream2_get_le32(&gb) != MKTAG('W', 'E', 'B', 'P')) {
+ av_log(avctx, AV_LOG_ERROR, "missing WEBP tag\n");
+ return AVERROR_INVALIDDATA;
+ }
+ s->vp8x_flags = 0;
+ s->canvas_width = 0;
+ s->canvas_height = 0;
+ s->has_exif = 0;
+ s->has_iccp = 0;
+ ff_thread_release_ext_buffer(&s->canvas_frame);
+ break;
case MKTAG('V', 'P', '8', ' '):
if (!*got_frame) {
- ret = vp8_lossy_decode_frame(avctx, p, got_frame,
- avpkt->data + bytestream2_tell(&gb),
+ ret = init_canvas_frame(s, AV_PIX_FMT_YUVA420P, key_frame);
+ if (ret < 0)
+ return ret;
+
+ ret = vp8_lossy_decode_frame(avctx, s->frame, got_frame,
+ data + bytestream2_tell(&gb),
chunk_size);
if (ret < 0)
return ret;
@@ -1416,24 +1444,35 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
break;
case MKTAG('V', 'P', '8', 'L'):
if (!*got_frame) {
- ret = vp8_lossless_decode_frame(avctx, p, got_frame,
- avpkt->data + bytestream2_tell(&gb),
+ ret = init_canvas_frame(s, AV_PIX_FMT_ARGB, key_frame);
+ if (ret < 0)
+ return ret;
+
+ ret = vp8_lossless_decode_frame(avctx, s->frame, got_frame,
+ data + bytestream2_tell(&gb),
chunk_size, 0);
if (ret < 0)
return ret;
+
avctx->properties |= FF_CODEC_PROPERTY_LOSSLESS;
+ ret = av_frame_copy_props(s->canvas_frame.f, s->frame);
+ if (ret < 0)
+ return ret;
+ ff_thread_finish_setup(s->avctx);
}
bytestream2_skip(&gb, chunk_size);
break;
case MKTAG('V', 'P', '8', 'X'):
- if (s->width || s->height || *got_frame) {
+ if (s->canvas_width || s->canvas_height || *got_frame) {
av_log(avctx, AV_LOG_ERROR, "Canvas dimensions are already set\n");
return AVERROR_INVALIDDATA;
}
- vp8x_flags = bytestream2_get_byte(&gb);
+ s->vp8x_flags = bytestream2_get_byte(&gb);
bytestream2_skip(&gb, 3);
s->width = bytestream2_get_le24(&gb) + 1;
s->height = bytestream2_get_le24(&gb) + 1;
+ s->canvas_width = s->width;
+ s->canvas_height = s->height;
ret = av_image_check_size(s->width, s->height, 0, avctx);
if (ret < 0)
return ret;
@@ -1441,7 +1480,7 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
case MKTAG('A', 'L', 'P', 'H'): {
int alpha_header, filter_m, compression;
- if (!(vp8x_flags & VP8X_FLAG_ALPHA)) {
+ if (!(s->vp8x_flags & VP8X_FLAG_ALPHA)) {
av_log(avctx, AV_LOG_WARNING,
"ALPHA chunk present, but alpha bit not set in the "
"VP8X header\n");
@@ -1450,8 +1489,9 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
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 = data + bytestream2_tell(&gb);
s->alpha_data_size = chunk_size - 1;
bytestream2_skip(&gb, s->alpha_data_size);
@@ -1471,37 +1511,33 @@ static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
}
case MKTAG('E', 'X', 'I', 'F'): {
int le, ifd_offset, exif_offset = bytestream2_tell(&gb);
- AVDictionary *exif_metadata = NULL;
+ AVDictionary **exif_metadata = NULL;
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))
+ if (!(s->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);
+ bytestream2_init(&exif_gb, data + exif_offset, 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;
}
+ exif_metadata = (s->vp8x_flags & VP8X_FLAG_ANIMATION) ? &p->metadata : &s->frame->metadata;
bytestream2_seek(&exif_gb, ifd_offset, SEEK_SET);
- if (ff_exif_decode_ifd(avctx, &exif_gb, le, 0, &exif_metadata) < 0) {
+ if (ff_exif_decode_ifd(avctx, &exif_gb, le, 0, exif_metadata) < 0) {
av_log(avctx, AV_LOG_ERROR, "error decoding Exif data\n");
goto exif_end;
}
-
- av_dict_copy(&p->metadata, exif_metadata, 0);
-
exif_end:
- av_dict_free(&exif_metadata);
bytestream2_skip(&gb, chunk_size);
break;
}
@@ -1513,13 +1549,12 @@ exif_end:
bytestream2_skip(&gb, chunk_size);
break;
}
- if (!(vp8x_flags & VP8X_FLAG_ICC))
+ if (!(s->vp8x_flags & VP8X_FLAG_ICC))
av_log(avctx, AV_LOG_WARNING,
"ICCP chunk present, but ICC Profile bit not set in the "
"VP8X header\n");
s->has_iccp = 1;
-
ret = ff_frame_new_side_data(avctx, p, AV_FRAME_DATA_ICC_PROFILE, chunk_size, &sd);
if (ret < 0)
return ret;
@@ -1531,8 +1566,51 @@ exif_end:
}
break;
}
- case MKTAG('A', 'N', 'I', 'M'):
+ case MKTAG('A', 'N', 'I', 'M'): {
+ const AVPixFmtDescriptor *desc;
+ int a, r, g, b;
+ if (!(s->vp8x_flags & VP8X_FLAG_ANIMATION)) {
+ av_log(avctx, AV_LOG_WARNING,
+ "ANIM chunk present, but animation bit not set in the "
+ "VP8X header\n");
+ }
+ // background is stored as BGRA, we need ARGB
+ s->background_argb[3] = b = bytestream2_get_byte(&gb);
+ s->background_argb[2] = g = bytestream2_get_byte(&gb);
+ s->background_argb[1] = r = bytestream2_get_byte(&gb);
+ s->background_argb[0] = a = bytestream2_get_byte(&gb);
+
+ // convert the background color to YUVA
+ desc = av_pix_fmt_desc_get(AV_PIX_FMT_YUVA420P);
+ s->background_yuva[desc->comp[0].plane] = RGB_TO_Y_CCIR(r, g, b);
+ s->background_yuva[desc->comp[1].plane] = RGB_TO_U_CCIR(r, g, b, 0);
+ s->background_yuva[desc->comp[2].plane] = RGB_TO_V_CCIR(r, g, b, 0);
+ s->background_yuva[desc->comp[3].plane] = a;
+
+ bytestream2_skip(&gb, 2); // loop count is ignored
+ break;
+ }
case MKTAG('A', 'N', 'M', 'F'):
+ if (!(s->vp8x_flags & VP8X_FLAG_ANIMATION)) {
+ av_log(avctx, AV_LOG_WARNING,
+ "ANMF chunk present, but animation bit not set in the "
+ "VP8X header\n");
+ }
+ s->pos_x = bytestream2_get_le24(&gb) * 2;
+ s->pos_y = bytestream2_get_le24(&gb) * 2;
+ s->width = bytestream2_get_le24(&gb) + 1;
+ s->height = bytestream2_get_le24(&gb) + 1;
+ bytestream2_skip(&gb, 3); // duration
+ s->anmf_flags = bytestream2_get_byte(&gb);
+
+ if (s->width + s->pos_x > s->canvas_width ||
+ s->height + s->pos_y > s->canvas_height) {
+ av_log(avctx, AV_LOG_ERROR,
+ "frame does not fit into canvas\n");
+ return AVERROR_INVALIDDATA;
+ }
+ s->vp8x_flags |= VP8X_FLAG_ANIMATION;
+ break;
case MKTAG('X', 'M', 'P', ' '):
AV_WL32(chunk_str, chunk_type);
av_log(avctx, AV_LOG_WARNING, "skipping unsupported chunk: %s\n",
@@ -1548,24 +1626,494 @@ exif_end:
}
}
- if (!*got_frame) {
- av_log(avctx, AV_LOG_ERROR, "image data not found\n");
- return AVERROR_INVALIDDATA;
+ return size;
+}
+
+int init_canvas_frame(WebPContext *s, int format, int key_frame)
+{
+ AVFrame *canvas = s->canvas_frame.f;
+ int height;
+ int ret;
+
+ // canvas is needed only for animation
+ if (!(s->vp8x_flags & VP8X_FLAG_ANIMATION))
+ return 0;
+
+ // avoid init for non-key frames whose format and size did not change
+ if (!key_frame &&
+ canvas->data[0] &&
+ canvas->format == format &&
+ canvas->width == s->canvas_width &&
+ canvas->height == s->canvas_height)
+ return 0;
+
+ // canvas changes within IPPP sequences will loose thread sync
+ // because of the ThreadFrame reallocation and will wait forever
+ // so if frame-threading is used, forbid canvas changes and unlock
+ // previous frames
+ if (!key_frame && canvas->data[0]) {
+ if (s->avctx->thread_count > 1) {
+ av_log(s->avctx, AV_LOG_WARNING, "Canvas change detected. The output will be damaged. Use -threads 1 to try decoding with best effort.\n");
+ // unlock previous frames that have sent an _await() call
+ ff_thread_report_progress(&s->canvas_frame, INT_MAX, 0);
+ return AVERROR_PATCHWELCOME;
+ } else {
+ // warn for damaged frames
+ av_log(s->avctx, AV_LOG_WARNING, "Canvas change detected. The output will be damaged.\n");
+ }
+ }
+
+ s->avctx->pix_fmt = format;
+ canvas->format = format;
+ canvas->width = s->canvas_width;
+ canvas->height = s->canvas_height;
+
+ // VP8 decoder changed the width and height in AVCodecContext.
+ // Change it back to the canvas size.
+ ret = ff_set_dimensions(s->avctx, s->canvas_width, s->canvas_height);
+ if (ret < 0)
+ return ret;
+
+ ff_thread_release_ext_buffer(s->avctx, &s->canvas_frame);
+ ret = ff_thread_get_ext_buffer(s->avctx, &s->canvas_frame, AV_GET_BUFFER_FLAG_REF);
+ if (ret < 0)
+ return ret;
+
+ if (canvas->format == AV_PIX_FMT_ARGB) {
+ height = canvas->height;
+ memset(canvas->data[0], 0, height * canvas->linesize[0]);
+ } else /* if (canvas->format == AV_PIX_FMT_YUVA420P) */ {
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(canvas->format);
+ for (int comp = 0; comp < desc->nb_components; comp++) {
+ int plane = desc->comp[comp].plane;
+
+ if (comp == 1 || comp == 2)
+ height = AV_CEIL_RSHIFT(canvas->height, desc->log2_chroma_h);
+ else
+ height = FFALIGN(canvas->height, 1 << desc->log2_chroma_h);
+
+ memset(canvas->data[plane], s->transparent_yuva[plane],
+ height * canvas->linesize[plane]);
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Blend src1 (foreground) and src2 (background) into dest, in ARGB format.
+ * width, height are the dimensions of src1
+ * pos_x, pos_y is the position in src2 and in dest
+ */
+static void blend_alpha_argb(uint8_t *dest_data[4], int dest_linesize[4],
+ const uint8_t *src1_data[4], int src1_linesize[4],
+ const uint8_t *src2_data[4], int src2_linesize[4],
+ int src2_step[4],
+ int width, int height, int pos_x, int pos_y)
+{
+ for (int y = 0; y < height; y++) {
+ const uint8_t *src1 = src1_data[0] + y * src1_linesize[0];
+ const uint8_t *src2 = src2_data[0] + (y + pos_y) * src2_linesize[0] + pos_x * src2_step[0];
+ uint8_t *dest = dest_data[0] + (y + pos_y) * dest_linesize[0] + pos_x * sizeof(uint32_t);
+ for (int x = 0; x < width; x++) {
+ int src1_alpha = src1[0];
+ int src2_alpha = src2[0];
+
+ if (src1_alpha == 255) {
+ memcpy(dest, src1, sizeof(uint32_t));
+ } else if (src1_alpha + src2_alpha == 0) {
+ memset(dest, 0, sizeof(uint32_t));
+ } else {
+ int tmp_alpha = src2_alpha - ROUNDED_DIV(src1_alpha * src2_alpha, 255);
+ int blend_alpha = src1_alpha + tmp_alpha;
+
+ dest[0] = blend_alpha;
+ dest[1] = ROUNDED_DIV(src1[1] * src1_alpha + src2[1] * tmp_alpha, blend_alpha);
+ dest[2] = ROUNDED_DIV(src1[2] * src1_alpha + src2[2] * tmp_alpha, blend_alpha);
+ dest[3] = ROUNDED_DIV(src1[3] * src1_alpha + src2[3] * tmp_alpha, blend_alpha);
+ }
+ src1 += sizeof(uint32_t);
+ src2 += src2_step[0];
+ dest += sizeof(uint32_t);
+ }
+ }
+}
+
+/*
+ * Blend src1 (foreground) and src2 (background) into dest, in YUVA format.
+ * width, height are the dimensions of src1
+ * pos_x, pos_y is the position in src2 and in dest
+ */
+static void blend_alpha_yuva(WebPContext *s,
+ uint8_t *dest_data[4], int dest_linesize[4],
+ const uint8_t *src1_data[4], int src1_linesize[4],
+ int src1_format,
+ const uint8_t *src2_data[4], int src2_linesize[4],
+ int src2_step[4],
+ int width, int height, int pos_x, int pos_y)
+{
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(src1_format);
+
+ int plane_y = desc->comp[0].plane;
+ int plane_u = desc->comp[1].plane;
+ int plane_v = desc->comp[2].plane;
+ int plane_a = desc->comp[3].plane;
+
+ // blend U & V planes first, because the later step may modify alpha plane
+ int w = AV_CEIL_RSHIFT(width, desc->log2_chroma_w);
+ int h = AV_CEIL_RSHIFT(height, desc->log2_chroma_h);
+ int px = AV_CEIL_RSHIFT(pos_x, desc->log2_chroma_w);
+ int py = AV_CEIL_RSHIFT(pos_y, desc->log2_chroma_h);
+ int tile_w = 1 << desc->log2_chroma_w;
+ int tile_h = 1 << desc->log2_chroma_h;
+
+ for (int y = 0; y < h; y++) {
+ const uint8_t *src1_u = src1_data[plane_u] + y * src1_linesize[plane_u];
+ const uint8_t *src1_v = src1_data[plane_v] + y * src1_linesize[plane_v];
+ const uint8_t *src2_u = src2_data[plane_u] + (y + py) * src2_linesize[plane_u] + px * src2_step[plane_u];
+ const uint8_t *src2_v = src2_data[plane_v] + (y + py) * src2_linesize[plane_v] + px * src2_step[plane_v];
+ uint8_t *dest_u = dest_data[plane_u] + (y + py) * dest_linesize[plane_u] + px;
+ uint8_t *dest_v = dest_data[plane_v] + (y + py) * dest_linesize[plane_v] + px;
+ for (int x = 0; x < w; x++) {
+ // calculate the average alpha of the tile
+ int src1_alpha = 0;
+ int src2_alpha = 0;
+ for (int yy = 0; yy < tile_h; yy++) {
+ for (int xx = 0; xx < tile_w; xx++) {
+ src1_alpha += src1_data[plane_a][(y * tile_h + yy) * src1_linesize[plane_a] +
+ (x * tile_w + xx)];
+ src2_alpha += src2_data[plane_a][((y + py) * tile_h + yy) * src2_linesize[plane_a] +
+ ((x + px) * tile_w + xx) * src2_step[plane_a]];
+ }
+ }
+ src1_alpha = AV_CEIL_RSHIFT(src1_alpha, desc->log2_chroma_w + desc->log2_chroma_h);
+ src2_alpha = AV_CEIL_RSHIFT(src2_alpha, desc->log2_chroma_w + desc->log2_chroma_h);
+
+ if (src1_alpha == 255) {
+ *dest_u = *src1_u;
+ *dest_v = *src1_v;
+ } else if (src1_alpha + src2_alpha == 0) {
+ *dest_u = s->transparent_yuva[plane_u];
+ *dest_v = s->transparent_yuva[plane_v];
+ } else {
+ int tmp_alpha = src2_alpha - ROUNDED_DIV(src1_alpha * src2_alpha, 255);
+ int blend_alpha = src1_alpha + tmp_alpha;
+ *dest_u = ROUNDED_DIV(*src1_u * src1_alpha + *src2_u * tmp_alpha, blend_alpha);
+ *dest_v = ROUNDED_DIV(*src1_v * src1_alpha + *src2_v * tmp_alpha, blend_alpha);
+ }
+ src1_u++;
+ src1_v++;
+ src2_u += src2_step[plane_u];
+ src2_v += src2_step[plane_v];
+ dest_u++;
+ dest_v++;
+ }
+ }
+
+ // blend Y & A planes
+ for (int y = 0; y < height; y++) {
+ const uint8_t *src1_y = src1_data[plane_y] + y * src1_linesize[plane_y];
+ const uint8_t *src1_a = src1_data[plane_a] + y * src1_linesize[plane_a];
+ const uint8_t *src2_y = src2_data[plane_y] + (y + pos_y) * src2_linesize[plane_y] + pos_x * src2_step[plane_y];
+ const uint8_t *src2_a = src2_data[plane_a] + (y + pos_y) * src2_linesize[plane_a] + pos_x * src2_step[plane_a];
+ uint8_t *dest_y = dest_data[plane_y] + (y + pos_y) * dest_linesize[plane_y] + pos_x;
+ uint8_t *dest_a = dest_data[plane_a] + (y + pos_y) * dest_linesize[plane_a] + pos_x;
+ for (int x = 0; x < width; x++) {
+ int src1_alpha = *src1_a;
+ int src2_alpha = *src2_a;
+
+ if (src1_alpha == 255) {
+ *dest_y = *src1_y;
+ *dest_a = 255;
+ } else if (src1_alpha + src2_alpha == 0) {
+ *dest_y = s->transparent_yuva[plane_y];
+ *dest_a = 0;
+ } else {
+ int tmp_alpha = src2_alpha - ROUNDED_DIV(src1_alpha * src2_alpha, 255);
+ int blend_alpha = src1_alpha + tmp_alpha;
+ *dest_y = ROUNDED_DIV(*src1_y * src1_alpha + *src2_y * tmp_alpha, blend_alpha);
+ *dest_a = blend_alpha;
+ }
+ src1_y++;
+ src1_a++;
+ src2_y += src2_step[plane_y];
+ src2_a += src2_step[plane_a];
+ dest_y++;
+ dest_a++;
+ }
}
+}
+
+static int blend_frame_into_canvas(WebPContext *s)
+{
+ AVFrame *canvas = s->canvas_frame.f;
+ AVFrame *frame = s->frame;
+ int width, height;
+ int pos_x, pos_y;
+
+ if ((s->anmf_flags & ANMF_BLENDING_METHOD) == ANMF_BLENDING_METHOD_OVERWRITE
+ || frame->format == AV_PIX_FMT_YUV420P) {
+ // do not blend, overwrite
+
+ if (canvas->format == AV_PIX_FMT_ARGB) {
+ width = s->width;
+ height = s->height;
+ pos_x = s->pos_x;
+ pos_y = s->pos_y;
+
+ for (int y = 0; y < height; y++) {
+ const uint32_t *src = (uint32_t *) (frame->data[0] + y * frame->linesize[0]);
+ uint32_t *dst = (uint32_t *) (canvas->data[0] + (y + pos_y) * canvas->linesize[0]) + pos_x;
+ memcpy(dst, src, width * sizeof(uint32_t));
+ }
+ } else /* if (canvas->format == AV_PIX_FMT_YUVA420P) */ {
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
+ int plane;
+
+ for (int comp = 0; comp < desc->nb_components; comp++) {
+ plane = desc->comp[comp].plane;
+ width = s->width;
+ height = s->height;
+ pos_x = s->pos_x;
+ pos_y = s->pos_y;
+ if (comp == 1 || comp == 2) {
+ width = AV_CEIL_RSHIFT(width, desc->log2_chroma_w);
+ height = AV_CEIL_RSHIFT(height, desc->log2_chroma_h);
+ pos_x = AV_CEIL_RSHIFT(pos_x, desc->log2_chroma_w);
+ pos_y = AV_CEIL_RSHIFT(pos_y, desc->log2_chroma_h);
+ }
+
+ for (int y = 0; y < height; y++) {
+ const uint8_t *src = frame->data[plane] + y * frame->linesize[plane];
+ uint8_t *dst = canvas->data[plane] + (y + pos_y) * canvas->linesize[plane] + pos_x;
+ memcpy(dst, src, width);
+ }
+ }
+
+ if (desc->nb_components < 4) {
+ // frame does not have alpha, set alpha to 255
+ desc = av_pix_fmt_desc_get(canvas->format);
+ plane = desc->comp[3].plane;
+ width = s->width;
+ height = s->height;
+ pos_x = s->pos_x;
+ pos_y = s->pos_y;
+
+ for (int y = 0; y < height; y++) {
+ uint8_t *dst = canvas->data[plane] + (y + pos_y) * canvas->linesize[plane] + pos_x;
+ memset(dst, 255, width);
+ }
+ }
+ }
+ } else {
+ // alpha blending
+
+ if (canvas->format == AV_PIX_FMT_ARGB) {
+ int src2_step[4] = { sizeof(uint32_t) };
+ blend_alpha_argb(canvas->data, canvas->linesize,
+ (const uint8_t **) frame->data, frame->linesize,
+ (const uint8_t **) canvas->data, canvas->linesize,
+ src2_step, s->width, s->height, s->pos_x, s->pos_y);
+ } else /* if (canvas->format == AV_PIX_FMT_YUVA420P) */ {
+ int src2_step[4] = { 1, 1, 1, 1 };
+ blend_alpha_yuva(s, canvas->data, canvas->linesize,
+ (const uint8_t **) frame->data, frame->linesize,
+ frame->format,
+ (const uint8_t **) canvas->data, canvas->linesize,
+ src2_step, s->width, s->height, s->pos_x, s->pos_y);
+ }
+ }
+
+ return 0;
+}
+
+static int copy_canvas_to_frame(WebPContext *s, AVFrame *frame, int key_frame)
+{
+ AVFrame *canvas = s->canvas_frame.f;
+ int ret;
+
+ frame->format = canvas->format;
+ frame->width = canvas->width;
+ frame->height = canvas->height;
+
+ ret = av_frame_get_buffer(frame, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = av_frame_copy_props(frame, canvas);
+ if (ret < 0)
+ return ret;
+
+ // blend the canvas with the background color into the output frame
+ if (canvas->format == AV_PIX_FMT_ARGB) {
+ int src2_step[4] = { 0 };
+ const uint8_t *src2_data[4] = { &s->background_argb[0] };
+ blend_alpha_argb(frame->data, frame->linesize,
+ (const uint8_t **) canvas->data, canvas->linesize,
+ (const uint8_t **) src2_data, src2_step, src2_step,
+ canvas->width, canvas->height, 0, 0);
+ } else /* if (canvas->format == AV_PIX_FMT_YUVA420P) */ {
+ int src2_step[4] = { 0, 0, 0, 0 };
+ blend_alpha_yuva(s, frame->data, frame->linesize,
+ (const uint8_t **) canvas->data, canvas->linesize,
+ canvas->format,
+ s->background_data, src2_step, src2_step,
+ canvas->width, canvas->height, 0, 0);
+ }
+
+ if (key_frame) {
+ frame->pict_type = AV_PICTURE_TYPE_I;
+ } else {
+ frame->pict_type = AV_PICTURE_TYPE_P;
+ }
+
+ return 0;
+}
- return avpkt->size;
+static int dispose_prev_frame_in_canvas(WebPContext *s)
+{
+ AVFrame *canvas = s->canvas_frame.f;
+ int width, height;
+ int pos_x, pos_y;
+
+ if ((s->prev_anmf_flags & ANMF_DISPOSAL_METHOD) == ANMF_DISPOSAL_METHOD_BACKGROUND) {
+ // dispose to background
+
+ if (canvas->format == AV_PIX_FMT_ARGB) {
+ width = s->prev_width;
+ height = s->prev_height;
+ pos_x = s->prev_pos_x;
+ pos_y = s->prev_pos_y;
+
+ for (int y = 0; y < height; y++) {
+ uint32_t *dst = (uint32_t *) (canvas->data[0] + (y + pos_y) * canvas->linesize[0]) + pos_x;
+ memset(dst, 0, width * sizeof(uint32_t));
+ }
+ } else /* if (canvas->format == AV_PIX_FMT_YUVA420P) */ {
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(canvas->format);
+ int plane;
+
+ for (int comp = 0; comp < desc->nb_components; comp++) {
+ plane = desc->comp[comp].plane;
+ width = s->prev_width;
+ height = s->prev_height;
+ pos_x = s->prev_pos_x;
+ pos_y = s->prev_pos_y;
+ if (comp == 1 || comp == 2) {
+ width = AV_CEIL_RSHIFT(width, desc->log2_chroma_w);
+ height = AV_CEIL_RSHIFT(height, desc->log2_chroma_h);
+ pos_x = AV_CEIL_RSHIFT(pos_x, desc->log2_chroma_w);
+ pos_y = AV_CEIL_RSHIFT(pos_y, desc->log2_chroma_h);
+ }
+
+ for (int y = 0; y < height; y++) {
+ uint8_t *dst = canvas->data[plane] + (y + pos_y) * canvas->linesize[plane] + pos_x;
+ memset(dst, s->transparent_yuva[plane], width);
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int webp_decode_frame(AVCodecContext *avctx, AVFrame *p,
+ int *got_frame, AVPacket *avpkt)
+{
+ WebPContext *s = avctx->priv_data;
+ int ret;
+ int key_frame = avpkt->flags & AV_PKT_FLAG_KEY;
+
+ *got_frame = 0;
+
+ if (key_frame) {
+ // The canvas is passed from one thread to another in a sequence
+ // starting with a key frame followed by non-key frames.
+ // The key frame reports progress 1,
+ // the N-th non-key frame awaits progress N = s->await_progress
+ // and reports progress N + 1.
+ s->await_progress = 0;
+ }
+
+ // reset the frame params
+ s->anmf_flags = 0;
+ s->width = 0;
+ s->height = 0;
+ s->pos_x = 0;
+ s->pos_y = 0;
+ s->has_alpha = 0;
+
+ ret = webp_decode_frame_common(avctx, avpkt->data, avpkt->size, got_frame, key_frame, p);
+ if (ret < 0)
+ goto end;
+
+ if (*got_frame) {
+ if (!(s->vp8x_flags & VP8X_FLAG_ANIMATION)) {
+ // no animation, output the decoded frame
+ av_frame_move_ref(p, s->frame);
+ } else {
+ if (!key_frame) {
+ ff_thread_await_progress(&s->canvas_frame, s->await_progress, 0);
+
+ ret = dispose_prev_frame_in_canvas(s);
+ if (ret < 0)
+ goto end;
+ }
+
+ ret = blend_frame_into_canvas(s);
+ if (ret < 0)
+ goto end;
+
+ ret = copy_canvas_to_frame(s, p, key_frame);
+ if (ret < 0)
+ goto end;
+
+ ff_thread_report_progress(&s->canvas_frame, s->await_progress + 1, 0);
+ }
+
+ p->pts = avpkt->pts;
+ }
+
+ ret = avpkt->size;
+
+end:
+ s->prev_anmf_flags = s->anmf_flags;
+ s->prev_width = s->width;
+ s->prev_height = s->height;
+ s->prev_pos_x = s->pos_x;
+ s->prev_pos_y = s->pos_y;
+
+ av_frame_unref(s->frame);
+ return ret;
}
static av_cold int webp_decode_init(AVCodecContext *avctx)
{
WebPContext *s = avctx->priv_data;
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(AV_PIX_FMT_YUVA420P);
int ret;
const AVCodec *codec;
+ s->avctx = avctx;
s->pkt = av_packet_alloc();
- if (!s->pkt)
+ s->canvas_frame.f = av_frame_alloc();
+ s->frame = av_frame_alloc();
+ if (!s->pkt || !s->canvas_frame.f || !s->frame) {
+ av_packet_free(&s->pkt);
+ av_frame_free(&s->canvas_frame.f);
+ av_frame_free(&s->frame);
return AVERROR(ENOMEM);
+ }
+ // prepare data pointers for YUVA background
+ for (int i = 0; i < 4; i++)
+ s->background_data[i] = &s->background_yuva[i];
+
+ // convert transparent black from RGBA to YUVA
+ s->transparent_yuva[desc->comp[0].plane] = RGB_TO_Y_CCIR(0, 0, 0);
+ s->transparent_yuva[desc->comp[1].plane] = RGB_TO_U_CCIR(0, 0, 0, 0);
+ s->transparent_yuva[desc->comp[2].plane] = RGB_TO_V_CCIR(0, 0, 0, 0);
+ s->transparent_yuva[desc->comp[3].plane] = 0;
/* Prepare everything needed for VP8 decoding */
codec = avcodec_find_decoder(AV_CODEC_ID_VP8);
@@ -1589,13 +2137,52 @@ static av_cold int webp_decode_close(AVCodecContext *avctx)
WebPContext *s = avctx->priv_data;
av_packet_free(&s->pkt);
+ ff_thread_release_ext_buffer(&s->canvas_frame);
+ av_frame_free(&s->canvas_frame.f);
+ av_frame_free(&s->frame);
avcodec_free_context(&s->avctx_vp8);
- if (s->initialized)
- return ff_vp8_decode_free(avctx);
+ return 0;
+}
+
+static void webp_decode_flush(AVCodecContext *avctx)
+{
+ WebPContext *s = avctx->priv_data;
+
+ ff_thread_release_ext_buffer(&s->canvas_frame);
+}
+
+#if HAVE_THREADS
+static int webp_update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
+{
+ WebPContext *wsrc = src->priv_data;
+ WebPContext *wdst = dst->priv_data;
+ int ret;
+
+ if (dst == src)
+ return 0;
+
+ ff_thread_release_ext_buffer(&wdst->canvas_frame);
+ if (wsrc->canvas_frame.f->data[0] &&
+ (ret = ff_thread_ref_frame(&wdst->canvas_frame, &wsrc->canvas_frame)) < 0)
+ return ret;
+
+ wdst->vp8x_flags = wsrc->vp8x_flags;
+ wdst->canvas_width = wsrc->canvas_width;
+ wdst->canvas_height = wsrc->canvas_height;
+ wdst->prev_anmf_flags = wsrc->anmf_flags;
+ wdst->prev_width = wsrc->width;
+ wdst->prev_height = wsrc->height;
+ wdst->prev_pos_x = wsrc->pos_x;
+ wdst->prev_pos_y = wsrc->pos_y;
+ wdst->await_progress = wsrc->await_progress + 1;
+
+ memcpy(wdst->background_argb, wsrc->background_argb, sizeof(wsrc->background_argb));
+ memcpy(wdst->background_yuva, wsrc->background_yuva, sizeof(wsrc->background_yuva));
return 0;
}
+#endif
const FFCodec ff_webp_decoder = {
.p.name = "webp",
@@ -1603,9 +2190,12 @@ const FFCodec ff_webp_decoder = {
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_WEBP,
.priv_data_size = sizeof(WebPContext),
+ UPDATE_THREAD_CONTEXT(webp_update_thread_context),
.init = webp_decode_init,
FF_CODEC_DECODE_CB(webp_decode_frame),
.close = webp_decode_close,
+ .flush = webp_decode_flush,
+ .bsfs = "awebp2webp",
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
- .caps_internal = FF_CODEC_CAP_ICC_PROFILES,
+ .caps_internal = FF_CODEC_CAP_ICC_PROFILES | FF_CODEC_CAP_ALLOCATE_PROGRESS,
};
--
2.43.0
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