[FFmpeg-devel] [PATCH] ogg/vorbis: implement header packet skip in chained ogg bitstreams.
Romain Beauxis
romain.beauxis at gmail.com
Sun Jun 1 19:21:14 EEST 2025
This is a redo of 574f634e49847e2225ee50013afebf0de03ef013 using a flat
memory storage for the extradata.
PR review comments addressed:
* Use flat memory array
* Rename structure to follow convention
* Add stddef.h header
Bonus: libavcodec/vorbisdec.c diff is greatly improved!
---
libavcodec/vorbis_parser.h | 7 +++
libavcodec/vorbisdec.c | 45 ++++++++++++-----
libavformat/oggparsevorbis.c | 56 ++++++++++++++++++++--
tests/ref/fate/ogg-vorbis-chained-meta.txt | 3 --
4 files changed, 94 insertions(+), 17 deletions(-)
diff --git a/libavcodec/vorbis_parser.h b/libavcodec/vorbis_parser.h
index 789932ac49..9010723590 100644
--- a/libavcodec/vorbis_parser.h
+++ b/libavcodec/vorbis_parser.h
@@ -27,6 +27,7 @@
#define AVCODEC_VORBIS_PARSER_H
#include <stdint.h>
+#include <stddef.h>
typedef struct AVVorbisParseContext AVVorbisParseContext;
@@ -45,6 +46,12 @@ void av_vorbis_parse_free(AVVorbisParseContext **s);
#define VORBIS_FLAG_COMMENT 0x00000002
#define VORBIS_FLAG_SETUP 0x00000004
+typedef struct AVVorbisHeaderExtradata {
+ unsigned int header_type;
+ size_t header_size;
+ uint8_t header[];
+} AVVorbisHeaderExtradata;
+
/**
* Get the duration for a Vorbis packet.
*
diff --git a/libavcodec/vorbisdec.c b/libavcodec/vorbisdec.c
index adbd726183..177d3c95c2 100644
--- a/libavcodec/vorbisdec.c
+++ b/libavcodec/vorbisdec.c
@@ -43,6 +43,7 @@
#include "vorbis.h"
#include "vorbisdsp.h"
#include "vorbis_data.h"
+#include "vorbis_parser.h"
#include "xiph.h"
#define V_NB_BITS 8
@@ -1778,11 +1779,40 @@ static int vorbis_decode_frame(AVCodecContext *avctx, AVFrame *frame,
GetBitContext *gb = &vc->gb;
float *channel_ptrs[255];
int i, len, ret;
+ size_t new_extradata_size;
+ const uint8_t *new_extradata;
+ AVVorbisHeaderExtradata *new_header;
+ const uint8_t *header = NULL;
+ size_t header_size = 0;
+ const uint8_t *setup = NULL;
+ size_t setup_size = 0;
ff_dlog(NULL, "packet length %d \n", buf_size);
- if (*buf == 1 && buf_size > 7) {
- if ((ret = init_get_bits8(gb, buf + 1, buf_size - 1)) < 0)
+ new_extradata = av_packet_get_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA,
+ &new_extradata_size);
+
+ if (new_extradata) {
+ i = 0;
+ while (i < new_extradata_size) {
+ new_header = (AVVorbisHeaderExtradata *)(new_extradata+i);
+
+ if (new_header->header_type == VORBIS_FLAG_HEADER) {
+ header_size = new_header->header_size;
+ header = new_header->header;
+ }
+
+ if (new_header->header_type == VORBIS_FLAG_SETUP) {
+ setup_size = new_header->header_size;
+ setup = new_header->header;
+ }
+
+ i += sizeof(AVVorbisHeaderExtradata)+new_header->header_size;
+ }
+ }
+
+ if (header_size > 7 && *header == 1) {
+ if ((ret = init_get_bits8(gb, header + 1, header_size - 1)) < 0)
return ret;
vorbis_free(vc);
@@ -1801,16 +1831,10 @@ static int vorbis_decode_frame(AVCodecContext *avctx, AVFrame *frame,
}
avctx->sample_rate = vc->audio_samplerate;
- return buf_size;
- }
-
- if (*buf == 3 && buf_size > 7) {
- av_log(avctx, AV_LOG_DEBUG, "Ignoring comment header\n");
- return buf_size;
}
- if (*buf == 5 && buf_size > 7 && vc->channel_residues && !vc->modes) {
- if ((ret = init_get_bits8(gb, buf + 1, buf_size - 1)) < 0)
+ if (setup_size > 7 && *setup == 5 && vc->channel_residues && !vc->modes) {
+ if ((ret = init_get_bits8(gb, setup + 1, setup_size - 1)) < 0)
return ret;
if ((ret = vorbis_parse_setup_hdr(vc))) {
@@ -1818,7 +1842,6 @@ static int vorbis_decode_frame(AVCodecContext *avctx, AVFrame *frame,
vorbis_free(vc);
return ret;
}
- return buf_size;
}
if (!vc->channel_residues || !vc->modes) {
diff --git a/libavformat/oggparsevorbis.c b/libavformat/oggparsevorbis.c
index 62cc2da6de..7e812846fe 100644
--- a/libavformat/oggparsevorbis.c
+++ b/libavformat/oggparsevorbis.c
@@ -434,6 +434,9 @@ static int vorbis_packet(AVFormatContext *s, int idx)
struct ogg_stream *os = ogg->streams + idx;
struct oggvorbis_private *priv = os->private;
int duration, flags = 0;
+ int skip_packet = 0;
+ int ret, header_size;
+ AVVorbisHeaderExtradata *new_header;
if (!priv->vp)
return AVERROR_INVALIDDATA;
@@ -496,10 +499,57 @@ static int vorbis_packet(AVFormatContext *s, int idx)
if (duration < 0) {
os->pflags |= AV_PKT_FLAG_CORRUPT;
return 0;
- } else if (flags & VORBIS_FLAG_COMMENT) {
- vorbis_update_metadata(s, idx);
+ }
+
+ if (flags & VORBIS_FLAG_HEADER) {
+ ret = vorbis_parse_header(s, s->streams[idx], os->buf + os->pstart, os->psize);
+ if (ret < 0)
+ return ret;
+
+ header_size = sizeof(AVVorbisHeaderExtradata)+os->psize;
+ ret = av_reallocp(&os->new_extradata,
+ os->new_extradata_size+header_size);
+
+ if (ret < 0)
+ return ret;
+
+ new_header = (AVVorbisHeaderExtradata *)(os->new_extradata+os->new_extradata_size);
+ new_header->header_type = VORBIS_FLAG_HEADER;
+ new_header->header_size = os->psize;
+ memcpy(new_header->header, os->buf + os->pstart, os->psize);
+
+ os->new_extradata_size += header_size;
+
+ skip_packet = 1;
+ }
+
+ if (flags & VORBIS_FLAG_COMMENT) {
+ ret = vorbis_update_metadata(s, idx);
+ if (ret < 0)
+ return ret;
+
flags = 0;
+ skip_packet = 1;
+ }
+
+ if (flags & VORBIS_FLAG_SETUP) {
+ header_size = sizeof(AVVorbisHeaderExtradata)+os->psize;
+ ret = av_reallocp(&os->new_extradata,
+ os->new_extradata_size+header_size);
+
+ if (ret < 0)
+ return ret;
+
+ new_header = (AVVorbisHeaderExtradata *)(os->new_extradata+os->new_extradata_size);
+ new_header->header_type = VORBIS_FLAG_SETUP;
+ new_header->header_size = os->psize;
+ memcpy(new_header->header, os->buf + os->pstart, os->psize);
+
+ os->new_extradata_size += header_size;
+
+ skip_packet = 1;
}
+
os->pduration = duration;
}
@@ -521,7 +571,7 @@ static int vorbis_packet(AVFormatContext *s, int idx)
priv->final_duration += os->pduration;
}
- return 0;
+ return skip_packet;
}
const struct ogg_codec ff_vorbis_codec = {
diff --git a/tests/ref/fate/ogg-vorbis-chained-meta.txt b/tests/ref/fate/ogg-vorbis-chained-meta.txt
index b7a97c90e2..1206f86c1f 100644
--- a/tests/ref/fate/ogg-vorbis-chained-meta.txt
+++ b/tests/ref/fate/ogg-vorbis-chained-meta.txt
@@ -6,10 +6,7 @@ Stream ID: 0, frame PTS: 128, metadata: N/A
Stream ID: 0, packet PTS: 704, packet DTS: 704
Stream ID: 0, frame PTS: 704, metadata: N/A
Stream ID: 0, packet PTS: 0, packet DTS: 0
-Stream ID: 0, packet PTS: 0, packet DTS: 0
Stream ID: 0, new metadata: encoder=Lavc61.19.100 libvorbis:title=Second Stream
-Stream ID: 0, packet PTS: 0, packet DTS: 0
-Stream ID: 0, packet PTS: 0, packet DTS: 0
Stream ID: 0, frame PTS: 0, metadata: N/A
Stream ID: 0, packet PTS: 128, packet DTS: 128
Stream ID: 0, frame PTS: 128, metadata: N/A
--
2.39.5 (Apple Git-154)
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