Fixes: 4907
Adds support for demuxing of animated WebP.
The WebP demuxer splits the input stream into packets containing one frame.
It also sets the timing information properly.
Signed-off-by: Josef Zlomek <jo...@pex.com>
---
Changelog | 1 +
doc/demuxers.texi | 28 ++++
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/version.h | 2 +-
libavformat/webpdec.c | 322 +++++++++++++++++++++++++++++++++++++++
6 files changed, 354 insertions(+), 1 deletion(-)
create mode 100644 libavformat/webpdec.c
diff --git a/Changelog b/Changelog
index 1e41040a8e..fc0bbdca45 100644
--- a/Changelog
+++ b/Changelog
@@ -6,6 +6,7 @@ version <next>:
- MacCaption demuxer
- PGX decoder
- animated WebP parser/decoder
+- animated WebP demuxer
version 4.3:
diff --git a/doc/demuxers.texi b/doc/demuxers.texi
index 3c15ab9eee..9b5932308b 100644
--- a/doc/demuxers.texi
+++ b/doc/demuxers.texi
@@ -832,4 +832,32 @@ which in turn, acts as a ceiling for the size of scripts
that can be read.
Default is 1 MiB.
@end table
+@section webp
+
+Animated WebP demuxer.
+
+It accepts the following options:
+
+@table @option
+@item min_delay
+Set the minimum valid delay between frames in milliseconds.
+Range is 0 to 60000. Default value is 10.
+
+@item max_webp_delay
+Set the maximum valid delay between frames in milliseconds.
+Range is 0 to 16777215. Default value is 16777215 (over four hours),
+the maximum value allowed by the specification.
+
+@item default_delay
+Set the default delay between frames in milliseconds.
+Range is 0 to 60000. Default value is 100.
+
+@item ignore_loop
+WebP files can contain information to loop a certain number of times (or
+infinitely). If @option{ignore_loop} is set to 1, then the loop setting
+from the input will be ignored and looping will not occur. If set to 0,
+then looping will occur and will cycle the number of times according to
+the WebP. Default value is 1.
+@end table
+
@c man end DEMUXERS
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 26af859a28..93793de45d 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -557,6 +557,7 @@ OBJS-$(CONFIG_WEBM_MUXER) += matroskaenc.o
matroska.o \
wv.o vorbiscomment.o
OBJS-$(CONFIG_WEBM_DASH_MANIFEST_MUXER) += webmdashenc.o
OBJS-$(CONFIG_WEBM_CHUNK_MUXER) += webm_chunk.o
+OBJS-$(CONFIG_WEBP_DEMUXER) += webpdec.o
OBJS-$(CONFIG_WEBP_MUXER) += webpenc.o
OBJS-$(CONFIG_WEBVTT_DEMUXER) += webvttdec.o subtitles.o
OBJS-$(CONFIG_WEBVTT_MUXER) += webvttenc.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index f8527b1fd4..389273ea52 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -455,6 +455,7 @@ extern AVOutputFormat ff_webm_muxer;
extern AVInputFormat ff_webm_dash_manifest_demuxer;
extern AVOutputFormat ff_webm_dash_manifest_muxer;
extern AVOutputFormat ff_webm_chunk_muxer;
+extern AVInputFormat ff_webp_demuxer;
extern AVOutputFormat ff_webp_muxer;
extern AVInputFormat ff_webvtt_demuxer;
extern AVOutputFormat ff_webvtt_muxer;
diff --git a/libavformat/version.h b/libavformat/version.h
index 75c03fde0a..33cebed85e 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,7 +32,7 @@
// Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
// Also please add any ticket numbers that you believe might be affected here
#define LIBAVFORMAT_VERSION_MAJOR 58
-#define LIBAVFORMAT_VERSION_MINOR 48
+#define LIBAVFORMAT_VERSION_MINOR 49
#define LIBAVFORMAT_VERSION_MICRO 100
#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
diff --git a/libavformat/webpdec.c b/libavformat/webpdec.c
new file mode 100644
index 0000000000..8d6e6df9c0
--- /dev/null
+++ b/libavformat/webpdec.c
@@ -0,0 +1,322 @@
+/*
+ * WebP demuxer
+ * Copyright (c) 2020 Pexeso Inc.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * WebP demuxer.
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "libavutil/opt.h"
+#include "avformat.h"
+#include "internal.h"
+
+typedef struct WebPDemuxContext {
+ const AVClass *class;
+ /**
+ * Time span in milliseconds before the next frame
+ * should be drawn on screen.
+ */
+ int delay;
+ /**
+ * Minimum allowed delay between frames in milliseconds.
+ * Values below this threshold are considered to be invalid
+ * and set to value of default_delay.
+ */
+ int min_delay;
+ int max_delay;
+ int default_delay;
+
+ /**
+ * loop options
+ */
+ int total_iter;
+ int iter_count;
+ int ignore_loop;
+
+ int nb_frames;
+ int remaining_size;
+} WebPDemuxContext;
+
+/**
+ * Major web browsers display WebPs at ~10-15fps when rate is not
+ * explicitly set or have too low values. We assume default rate to be 10.
+ * Default delay = 1000 microseconds / 10fps = 100 milliseconds per frame.
+ */
+#define WEBP_DEFAULT_DELAY 100
+/**
+ * By default delay values less than this threshold considered to be invalid.
+ */
+#define WEBP_MIN_DELAY 10
+
+static int webp_probe(const AVProbeData *p)
+{
+ const uint8_t *b = p->buf;
+
+ if (p->filename && ff_guess_image2_codec(p->filename)) {
+ if (AV_RB32(b) == MKBETAG('R', 'I', 'F', 'F') &&
+ AV_RB32(b + 8) == MKBETAG('W', 'E', 'B', 'P'))
+ return AVPROBE_SCORE_MAX;
+ }
+
+ return 0;
+}
+
+static int resync(AVFormatContext *s)
+{
+ WebPDemuxContext *wdc = s->priv_data;
+ AVIOContext *pb = s->pb;
+ int i;
+ uint64_t state = 0;
+
+ for (i = 0; i < 12; i++) {
+ state = (state << 8) | avio_r8(pb);
+ if (i == 11) {
+ if ((uint32_t) state == MKBETAG('W', 'E', 'B', 'P'))
+ return 0;
+ i -= 4;
+ }
+ if (i == 7) {
+ if ((state >> 32) != MKBETAG('R', 'I', 'F', 'F')) {
+ i--;
+ } else {
+ uint32_t fsize = av_bswap32(state);
+ if (!(fsize > 15 && fsize <= UINT32_MAX - 10)) {
+ i -= 4;
+ } else {
+ wdc->remaining_size = fsize - 4;
+ }
+ }
+ }
+ if (avio_feof(pb))
+ return AVERROR_EOF;
+ }
+ return 0;
+}
+
+static int webp_read_header(AVFormatContext *s)
+{
+ WebPDemuxContext *wdc = s->priv_data;
+ AVIOContext *pb = s->pb;
+ AVStream *st;
+ int ret, n;
+ int64_t nb_frames = 0, duration = 0;
+ int width = 0, height = 0;
+ uint32_t chunk_type, chunk_size;
+
+ ret = resync(s);
+ if (ret < 0)
+ return ret;
+
+ st = avformat_new_stream(s, NULL);
+ if (!st)
+ return AVERROR(ENOMEM);
+
+ st->codecpar->width = 0;
+ st->codecpar->height = 0;
+ wdc->delay = wdc->default_delay;
+
+ while (1) {
+ chunk_type = avio_rl32(pb);
+ chunk_size = avio_rl32(pb);
+ if (chunk_size == UINT32_MAX)
+ return AVERROR_INVALIDDATA;
+ chunk_size += chunk_size & 1;
+ if (avio_feof(pb))
+ break;
+
+ switch (chunk_type) {
+ case MKTAG('V', 'P', '8', 'X'):
+ avio_skip(pb, 4);
+ width = avio_rl24(pb) + 1;
+ height = avio_rl24(pb) + 1;
+ break;
+ case MKTAG('V', 'P', '8', ' '):
+ avio_skip(pb, 6);
+ width = avio_rl16(pb) & 0x3fff;
+ height = avio_rl16(pb) & 0x3fff;
+ duration += wdc->delay;
+ nb_frames++;
+ avio_skip(pb, chunk_size - 10);
+ break;
+ case MKTAG('V', 'P', '8', 'L'):
+ avio_skip(pb, 1);
+ n = avio_rl32(pb);
+ width = (n & 0x3fff) + 1; /* first 14 bits */
+ height = ((n >> 14) & 0x3fff) + 1; /* next 14 bits */
+ duration += wdc->delay;
+ nb_frames++;
+ avio_skip(pb, chunk_size - 5);
+ break;
+ case MKTAG('A', 'N', 'M', 'F'):
+ avio_skip(pb, 6);
+ width = avio_rl24(pb) + 1;
+ height = avio_rl24(pb) + 1;
+ wdc->delay = avio_rl24(pb);
+ if (wdc->delay < wdc->min_delay)
+ wdc->delay = wdc->default_delay;
+ wdc->delay = FFMIN(wdc->delay, wdc->max_delay);
+ duration += wdc->delay;
+ nb_frames++;
+ avio_skip(pb, chunk_size - 15);
+ break;
+ default:
+ avio_skip(pb, chunk_size);
+ }
+
+ if (avio_feof(pb))
+ break;
+
+ if (st->codecpar->width == 0 && width > 0)
+ st->codecpar->width = width;
+ if (st->codecpar->height == 0 && height > 0)
+ st->codecpar->height = height;
+ }
+
+ /* WebP format operates with time in "milliseconds",
+ * therefore timebase is 1/1000 */
+ avpriv_set_pts_info(st, 64, 1, 1000);
+ st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+ st->codecpar->codec_id = AV_CODEC_ID_WEBP;
+ st->start_time = 0;
+ st->duration = duration;
+ st->nb_frames = nb_frames;
+
+ /* jump to start because WebP decoder needs header data too */
+ if (avio_seek(pb, 0, SEEK_SET) != 0)
+ return AVERROR(EIO);
+ wdc->remaining_size = 0;
+
+ return 0;
+}
+
+static int webp_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ WebPDemuxContext *wdc = s->priv_data;
+ AVIOContext *pb = s->pb;
+ int ret;
+ int64_t frame_start = avio_tell(pb), frame_end;
+ uint32_t chunk_type, chunk_size;
+ int is_frame = 0;
+
+ if (wdc->remaining_size == 0) {
+ ret = resync(s);
+ if (ret == AVERROR_EOF) {
+ if (!wdc->ignore_loop && avio_feof(pb)
+ && (wdc->total_iter < 0 || ++wdc->iter_count <
wdc->total_iter))
+ return avio_seek(pb, 0, SEEK_SET);
+ return AVERROR_EOF;
+ }
+ if (ret < 0)
+ return ret;
+
+ wdc->delay = wdc->default_delay;
+ }
+
+ while (!is_frame && wdc->remaining_size > 0 && !avio_feof(pb)) {
+ chunk_type = avio_rl32(pb);
+ chunk_size = avio_rl32(pb);
+ if (chunk_size == UINT32_MAX)
+ return AVERROR_INVALIDDATA;
+ chunk_size += chunk_size & 1;
+
+ if (wdc->remaining_size < 8 + chunk_size)
+ return AVERROR_INVALIDDATA;
+ wdc->remaining_size -= 8 + chunk_size;
+
+ switch (chunk_type) {
+ case MKTAG('A', 'N', 'I', 'M'):
+ avio_skip(pb, 4);
+ wdc->total_iter = avio_rl16(pb);
+ if (wdc->total_iter == 0)
+ wdc->total_iter = -1;
+ ret = avio_skip(pb, chunk_size - 6);
+ break;
+ case MKTAG('A', 'N', 'M', 'F'):
+ avio_skip(pb, 12);
+ wdc->delay = avio_rl24(pb);
+ if (wdc->delay < wdc->min_delay)
+ wdc->delay = wdc->default_delay;
+ wdc->delay = FFMIN(wdc->delay, wdc->max_delay);
+ wdc->nb_frames++;
+ is_frame = 1;
+ ret = avio_skip(pb, chunk_size - 15);
+ break;
+ case MKTAG('V', 'P', '8', ' '):
+ case MKTAG('V', 'P', '8', 'L'):
+ wdc->nb_frames++;
+ is_frame = 1;
+ /* fallthrough */
+ default:
+ ret = avio_skip(pb, chunk_size);
+ break;
+ }
+
+ if (ret < 0)
+ return ret;
+ }
+
+ frame_end = avio_tell(pb);
+
+ if (avio_seek(pb, frame_start, SEEK_SET) != frame_start)
+ return AVERROR(EIO);
+
+ ret = av_get_packet(pb, pkt, frame_end - frame_start);
+ if (ret < 0)
+ return ret;
+
+ pkt->flags |= AV_PKT_FLAG_KEY;
+ pkt->stream_index = 0;
+ pkt->duration = is_frame ? wdc->delay : 0;
+
+ if (is_frame && wdc->nb_frames == 1) {
+ s->streams[0]->r_frame_rate = (AVRational) {1000, pkt->duration};
+ }
+
+ return ret;
+}
+
+static const AVOption options[] = {
+ { "min_delay" , "minimum valid delay between frames (in
milliseconds)", offsetof(WebPDemuxContext, min_delay) , AV_OPT_TYPE_INT,
{.i64 = WEBP_MIN_DELAY} , 0, 1000 * 60, AV_OPT_FLAG_DECODING_PARAM },
+ { "max_webp_delay", "maximum valid delay between frames (in
milliseconds)", offsetof(WebPDemuxContext, max_delay) , AV_OPT_TYPE_INT,
{.i64 = 0xffffff} , 0, 0xffffff , AV_OPT_FLAG_DECODING_PARAM },
+ { "default_delay" , "default delay between frames (in milliseconds)"
, offsetof(WebPDemuxContext, default_delay), AV_OPT_TYPE_INT, {.i64 =
WEBP_DEFAULT_DELAY}, 0, 1000 * 60, AV_OPT_FLAG_DECODING_PARAM },
+ { "ignore_loop" , "ignore loop setting"
, offsetof(WebPDemuxContext, ignore_loop) , AV_OPT_TYPE_BOOL,{.i64 = 1}
, 0, 1 , AV_OPT_FLAG_DECODING_PARAM },
+ { NULL },
+};
+
+static const AVClass demuxer_class = {
+ .class_name = "WebP demuxer",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+ .category = AV_CLASS_CATEGORY_DEMUXER,
+};
+
+AVInputFormat ff_webp_demuxer = {
+ .name = "webp",
+ .long_name = NULL_IF_CONFIG_SMALL("WebP image"),
+ .priv_data_size = sizeof(WebPDemuxContext),
+ .read_probe = webp_probe,
+ .read_header = webp_read_header,
+ .read_packet = webp_read_packet,
+ .flags = AVFMT_GENERIC_INDEX,
+ .priv_class = &demuxer_class,
+};
--
2.17.1
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