On 4/1/25 12:29 PM, Peter Xia wrote:
Adds support of decoding animated webp.
Signed-off-by: Peter Xia <aat...@gmail.com>
---
Changelog | 1 +
configure | 4 +-
doc/general_contents.texi | 2 +-
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 3 +-
libavcodec/libwebpdec.c | 200 ++++++++++++++++++++++++++++++++++++++
libavcodec/version.h | 2 +-
7 files changed, 209 insertions(+), 4 deletions(-)
create mode 100644 libavcodec/libwebpdec.c
diff --git a/Changelog b/Changelog
index a03a79d17a..4635e16c05 100644
--- a/Changelog
+++ b/Changelog
@@ -12,6 +12,7 @@ version <next>:
- Animated JPEG XL encoding (via libjxl)
- VVC in Matroska
- CENC AV1 support in MP4 muxer
+- Animated WebP decoding
version 7.1:
- Raw Captions with Time (RCWT) closed caption demuxer
diff --git a/configure b/configure
index 4559962a4a..28a532641b 100755
--- a/configure
+++ b/configure
@@ -3611,6 +3611,7 @@ libvpx_vp9_encoder_deps="libvpx"
libvvenc_encoder_deps="libvvenc"
libwebp_encoder_deps="libwebp"
libwebp_anim_encoder_deps="libwebp"
+libwebp_decoder_deps="libwebp"
libx262_encoder_deps="libx262"
libx264_encoder_deps="libx264"
libx264_encoder_select="atsc_a53 golomb"
@@ -7081,7 +7082,8 @@ enabled libvpx && {
enabled libvvenc && require_pkg_config libvvenc "libvvenc >= 1.6.1"
"vvenc/vvenc.h" vvenc_get_version
enabled libwebp && {
enabled libwebp_encoder && require_pkg_config libwebp "libwebp >=
0.2.0" webp/encode.h WebPGetEncoderVersion
- enabled libwebp_anim_encoder && check_pkg_config libwebp_anim_encoder "libwebpmux
>= 0.4.0" webp/mux.h WebPAnimEncoderOptionsInit; }
+ enabled libwebp_anim_encoder && check_pkg_config libwebp_anim_encoder "libwebpmux
>= 0.4.0" webp/mux.h WebPAnimEncoderOptionsInit
+ enabled libwebp_decoder && check_pkg_config libwebp_decoder "libwebpdemux
>= 1.5.0" webp/demux.h WebPAnimDecoderOptionsInitInternal; }
enabled libx264 && require_pkg_config libx264 x264 "stdint.h x264.h"
x264_encoder_encode &&
require_cpp_condition libx264 x264.h "X264_BUILD >= 155"
&& {
[ "$toolchain" != "msvc" ] ||
diff --git a/doc/general_contents.texi b/doc/general_contents.texi
index 5faf89815b..4f10c3e34a 100644
--- a/doc/general_contents.texi
+++ b/doc/general_contents.texi
@@ -857,7 +857,7 @@ following image formats are supported:
@item WBMP @tab X @tab X
@tab Wireless Application Protocol Bitmap image format
@item WebP @tab E @tab X
- @tab WebP image format, encoding supported through external library libwebp
+ @tab WebP image format, supported through external library libwebp
@item XBM @tab X @tab X
@tab X BitMap image format
@item XFace @tab X @tab X
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b24201b1af..c9637a2114 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1179,6 +1179,7 @@ OBJS-$(CONFIG_LIBVPX_VP9_ENCODER) += libvpxenc.o
OBJS-$(CONFIG_LIBVVENC_ENCODER) += libvvenc.o
OBJS-$(CONFIG_LIBWEBP_ENCODER) += libwebpenc_common.o libwebpenc.o
OBJS-$(CONFIG_LIBWEBP_ANIM_ENCODER) += libwebpenc_common.o
libwebpenc_animencoder.o
+OBJS-$(CONFIG_LIBWEBP_DECODER) += libwebpdec.o
OBJS-$(CONFIG_LIBX262_ENCODER) += libx264.o
OBJS-$(CONFIG_LIBX264_ENCODER) += libx264.o
OBJS-$(CONFIG_LIBX265_ENCODER) += libx265.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index f10519617e..5f8f682111 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -810,8 +810,9 @@ extern FFCodec ff_libvpx_vp9_encoder;
extern const FFCodec ff_libvpx_vp9_decoder;
extern const FFCodec ff_libvvenc_encoder;
/* preferred over libwebp */
-extern const FFCodec ff_libwebp_anim_encoder;
extern const FFCodec ff_libwebp_encoder;
+extern const FFCodec ff_libwebp_anim_encoder;
+extern const FFCodec ff_libwebp_decoder;
extern const FFCodec ff_libx262_encoder;
extern const FFCodec ff_libx264_encoder;
extern const FFCodec ff_libx264rgb_encoder;
diff --git a/libavcodec/libwebpdec.c b/libavcodec/libwebpdec.c
new file mode 100644
index 0000000000..9ec3b60709
--- /dev/null
+++ b/libavcodec/libwebpdec.c
@@ -0,0 +1,200 @@
+/*
+ * LibWebP decoder
+ * Copyright (c) 2025 Peter Xia
+ *
+ * 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
+ * LibWebP decoder
+ */
+
+#include "decode.h"
+#include "codec_internal.h"
+#include "libavutil/avutil.h"
+#include "libavutil/opt.h"
+#include "libavformat/avformat.h"
+#include "libavformat/avio.h"
+
+#include <webp/demux.h>
+#include <webp/decode.h>
+
+typedef struct AnimatedWebPContext
+{
+ const AVClass *class;
+ WebPAnimDecoderOptions dec_options;
+ WebPAnimDecoder *dec;
+ AVBufferRef *file_content;
+ WebPData webp_data; // references |file_content|
+ uint32_t loop_to_send;
+ uint32_t loop_sent;
+
+ // --- Options ---
+ int ignore_loop;
+} AnimatedWebPContext;
+
+// Initialize the decoder context
+static av_cold int decode_libwebp_init(AVCodecContext *avctx)
+{
+ AnimatedWebPContext *s = avctx->priv_data;
+
+ if (!WebPAnimDecoderOptionsInit(&s->dec_options))
+ {
Braces for if-statements should be on the same line as the if-statement
+ av_log(avctx, AV_LOG_DEBUG, "Cannot initialize
WebPAnimDecoderOptions\n");
+ return AVERROR(ENOMEM);
+ }
+ s->dec_options.color_mode = MODE_RGBA;
+ s->dec_options.use_threads = 1;
+ s->file_content = NULL;
+ s->loop_sent = 0;
+
+ avctx->pix_fmt = AV_PIX_FMT_RGBA;
+ avctx->pkt_timebase = av_make_q(1, 1000);
+ avctx->framerate = av_make_q(1, 0);
+
+ av_log(avctx, AV_LOG_DEBUG, "Animated WebP decoder initialized.\n");
+ return 0; // Success
+}
+
+// Decode one frame of the animated WebP
+// This function will be called multiple times by FFmpeg.
+// The first call receives the AVPacket with the full WebP file.
+// Subsequent calls receive empty AVPacket until all frames are decoded.
These comments should probably be in Javadoc format
+static int decode_libwebp_frame(AVCodecContext *avctx, AVFrame *p,
+ int *got_frame, AVPacket *avpkt)
+{
+ av_log(avctx, AV_LOG_INFO, "decode_libwebp_frame()\n");
+
+ WebPAnimInfo anim_info;
This gives a -Wdeclaration-after-statement warning
(though that wouldn't matter if
https://patchwork.ffmpeg.org/project/ffmpeg/patch/as8p250mb07446ae8c7cddd1ac795dd568f...@as8p250mb0744.eurp250.prod.outlook.com/
is merged)
+ uint8_t *frame_rgba;
+ int timestamp_ms;
+
+ AnimatedWebPContext *s = avctx->priv_data;
+ int ret = avpkt->size;
+
+ // Initialization Phase (First Call)
+ // |avpkt| contains the entire file.
+ if (!s->dec)
+ {
+ if (!avpkt || avpkt->size <= 0)
+ {
+ // Should not happen on the first call, but check anyway.
+ av_log(avctx, AV_LOG_ERROR, "No input data provided on first
call.\n");
+ return AVERROR(EINVAL);
+ }
+
+ // Store entire WebP file in memory.
+ s->file_content = av_buffer_ref(avpkt->buf);
+ s->webp_data.bytes = s->file_content->data;
+ s->webp_data.size = s->file_content->size;
+
+ s->dec = WebPAnimDecoderNew(&s->webp_data, &s->dec_options);
+ if (!s->dec)
+ {
+ av_log(avctx, AV_LOG_ERROR, "Error creating WebPAnimDecoder.\n");
+ av_buffer_unref(&s->file_content);
+ return AVERROR(ENOMEM);
+ }
+
+ WebPAnimDecoderGetInfo(s->dec, &anim_info);
+
+ s->loop_to_send = s->ignore_loop ? 1 : anim_info.loop_count;
+ avctx->width = anim_info.canvas_width;
+ avctx->coded_width = anim_info.canvas_width;
+ avctx->height = anim_info.canvas_height;
+ avctx->coded_height = anim_info.canvas_height;
+ avctx->framerate = av_make_q(1, 0);
+ }
+
+ if (!WebPAnimDecoderHasMoreFrames(s->dec))
+ {
+ s->loop_sent++;
+ WebPAnimDecoderReset(s->dec);
+ }
+
+ if (s->loop_sent >= s->loop_to_send)
+ {
+ av_log(avctx, AV_LOG_DEBUG, "End of animated WebP stream.\n");
+ return AVERROR_EOF;
+ }
+
+
+ if (!WebPAnimDecoderGetNext(s->dec, &frame_rgba, ×tamp_ms))
+ {
+ av_log(avctx, AV_LOG_ERROR, "Error getting next frame from
WebPAnimDecoder.\n");
+ return AVERROR(EINVAL);
+ }
+
+ ret = ff_get_buffer(avctx, p, 0);
+ if (ret)
+ {
+ av_log(avctx, AV_LOG_ERROR, "Failed to allocated buffer.\n");
+ return AVERROR(ENOMEM);
+ }
+
+ p->width = avctx->width;
+ p->height = avctx->height;
+ p->format = AV_PIX_FMT_RGBA;
+ p->pts = timestamp_ms;
+ p->pkt_dts = 0;
+ p->pict_type = AV_PICTURE_TYPE_I;
+
+ memcpy(p->data[0], frame_rgba, p->width * p->height * 4);
+
+ *got_frame = 1;
+ return ret;
+}
+
+static av_cold int decode_libwebp_close(AVCodecContext *avctx)
+{
+ AnimatedWebPContext *s = avctx->priv_data;
+ av_buffer_unref(&s->file_content);
+ if (s->dec)
+ {
+ WebPAnimDecoderDelete(s->dec);
+ s->dec = NULL;
+ }
+ return 0;
+}
+
+static const AVOption options[] = {
+ {"ignore_loop", "ignore loop setting (netscape extension)",
offsetof(AnimatedWebPContext, ignore_loop), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1,
AV_OPT_FLAG_DECODING_PARAM},
+ {NULL}};
This closing brace should be on its line
+
+static const AVClass libwebp_decoder_class = {
+ .class_name = "libwebp_decoder",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+ .category = AV_CLASS_CATEGORY_DECODER,
+};
+
+// Define the AVCodec structure for FFmpeg
+const FFCodec ff_libwebp_decoder = {
+ .p.name = "libwebp",
+ CODEC_LONG_NAME("libwebp image/animation decoder"),
+ .p.type = AVMEDIA_TYPE_VIDEO,
+ .p.id = AV_CODEC_ID_WEBP,
+ .p.priv_class = &libwebp_decoder_class,
+ .priv_data_size = sizeof(AnimatedWebPContext),
+ .p.wrapper_name = "libwebp",
+ .init = decode_libwebp_init,
+ FF_CODEC_DECODE_CB(decode_libwebp_frame),
+ .close = decode_libwebp_close,
+ .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY,
+};
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 8c3d476003..5957009457 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
This patch doesn't apply anymore because of a merge conflict
in this file since 839b419
(of course that's not your fault, but just a heads up!)
@@ -29,7 +29,7 @@
#include "version_major.h"
-#define LIBAVCODEC_VERSION_MINOR 0
+#define LIBAVCODEC_VERSION_MINOR 1
#define LIBAVCODEC_VERSION_MICRO 100
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
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