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/*
* Ogg muxer
* Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr>
*
* 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
*/
#include <stdint.h>
#include "libavutil/crc.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/random_seed.h"
#include "libavcodec/xiph.h"
#include "libavcodec/bytestream.h"
#include "libavcodec/flac.h"
#include "avformat.h"
#include "avio_internal.h"
#include "internal.h"
#include "vorbiscomment.h"
#define MAX_PAGE_SIZE 65025
typedef struct {
int64_t start_granule;
int64_t granule;
int stream_index;
uint8_t flags;
uint8_t segments_count;
uint8_t segments[255];
uint8_t data[MAX_PAGE_SIZE];
uint16_t size;
} OGGPage;
typedef struct {
unsigned page_counter;
uint8_t *header[3];
int header_len[3];
/** for theora granule */
int kfgshift;
int64_t last_kf_pts;
int vrev;
int eos;
unsigned page_count; ///< number of page buffered
OGGPage page; ///< current page
unsigned serial_num; ///< serial number
int64_t last_granule; ///< last packet granule
} OGGStreamContext;
typedef struct OGGPageList {
OGGPage page;
struct OGGPageList *next;
} OGGPageList;
typedef struct {
const AVClass *class;
OGGPageList *page_list;
int pref_size; ///< preferred page size (0 => fill all segments)
int64_t pref_duration; ///< preferred page duration (0 => fill all segments)
} OGGContext;
#define OFFSET(x) offsetof(OGGContext, x)
#define PARAM AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "oggpagesize", "Set preferred Ogg page size.",
offsetof(OGGContext, pref_size), AV_OPT_TYPE_INT, {.i64 = 0}, 0, MAX_PAGE_SIZE, AV_OPT_FLAG_ENCODING_PARAM},
{ "pagesize", "preferred page size in bytes (deprecated)",
OFFSET(pref_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, MAX_PAGE_SIZE, PARAM },
{ "page_duration", "preferred page duration, in microseconds",
OFFSET(pref_duration), AV_OPT_TYPE_INT64, { .i64 = 1000000 }, 0, INT64_MAX, PARAM },
{ NULL },
};
static void ogg_update_checksum(AVFormatContext *s, AVIOContext *pb, int64_t crc_offset)
{
int64_t pos = avio_tell(pb);
uint32_t checksum = ffio_get_checksum(pb);
avio_seek(pb, crc_offset, SEEK_SET);
avio_wb32(pb, checksum);
avio_seek(pb, pos, SEEK_SET);
}
static int ogg_write_page(AVFormatContext *s, OGGPage *page, int extra_flags)
{
OGGStreamContext *oggstream = s->streams[page->stream_index]->priv_data;
AVIOContext *pb;
int64_t crc_offset;
int ret, size;
uint8_t *buf;
ret = avio_open_dyn_buf(&pb);
if (ret < 0)
return ret;
ffio_init_checksum(pb, ff_crc04C11DB7_update, 0);
ffio_wfourcc(pb, "OggS");
avio_w8(pb, 0);
avio_w8(pb, page->flags | extra_flags);
avio_wl64(pb, page->granule);
avio_wl32(pb, oggstream->serial_num);
avio_wl32(pb, oggstream->page_counter++);
crc_offset = avio_tell(pb);
avio_wl32(pb, 0); // crc
avio_w8(pb, page->segments_count);
avio_write(pb, page->segments, page->segments_count);
avio_write(pb, page->data, page->size);
ogg_update_checksum(s, pb, crc_offset);
avio_flush(pb);
size = avio_close_dyn_buf(pb, &buf);
if (size < 0)
return size;
avio_write(s->pb, buf, size);
avio_flush(s->pb);
av_free(buf);
oggstream->page_count--;
return 0;
}
static int ogg_key_granule(OGGStreamContext *oggstream, int64_t granule)
{
return oggstream->kfgshift && !(granule & ((1<<oggstream->kfgshift)-1));
}
static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t granule)
{
if (oggstream->kfgshift)
return (granule>>oggstream->kfgshift) +
(granule & ((1<<oggstream->kfgshift)-1));
else
return granule;
}
static int ogg_compare_granule(AVFormatContext *s, OGGPage *next, OGGPage *page)
{
AVStream *st2 = s->streams[next->stream_index];
AVStream *st = s->streams[page->stream_index];
int64_t next_granule, cur_granule;
if (next->granule == -1 || page->granule == -1)
return 0;
next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next->granule),
st2->time_base, AV_TIME_BASE_Q);
cur_granule = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page->granule),
st ->time_base, AV_TIME_BASE_Q);
return next_granule > cur_granule;
}
static int ogg_reset_cur_page(OGGStreamContext *oggstream)
{
oggstream->page.granule = -1;
oggstream->page.flags = 0;
oggstream->page.segments_count = 0;
oggstream->page.size = 0;
return 0;
}
static int ogg_buffer_page(AVFormatContext *s, OGGStreamContext *oggstream)
{
OGGContext *ogg = s->priv_data;
OGGPageList **p = &ogg->page_list;
OGGPageList *l = av_mallocz(sizeof(*l));
if (!l)
return AVERROR(ENOMEM);
l->page = oggstream->page;
oggstream->page.start_granule = oggstream->page.granule;
oggstream->page_count++;
ogg_reset_cur_page(oggstream);
while (*p) {
if (ogg_compare_granule(s, &(*p)->page, &l->page))
break;
p = &(*p)->next;
}
l->next = *p;
*p = l;
return 0;
}
static int ogg_buffer_data(AVFormatContext *s, AVStream *st,
uint8_t *data, unsigned size, int64_t granule,
int header)
{
OGGStreamContext *oggstream = st->priv_data;
OGGContext *ogg = s->priv_data;
int total_segments = size / 255 + 1;
uint8_t *p = data;
int i, segments, len, flush = 0;
// Handles VFR by flushing page because this frame needs to have a timestamp
// For theora, keyframes also need to have a timestamp to correctly mark
// them as such, otherwise seeking will not work correctly at the very
// least with old libogg versions.
// Do not try to flush header packets though, that will create broken files.
if (st->codec->codec_id == AV_CODEC_ID_THEORA && !header &&
(ogg_granule_to_timestamp(oggstream, granule) >
ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1 ||
ogg_key_granule(oggstream, granule))) {
if (oggstream->page.granule != -1)
ogg_buffer_page(s, oggstream);
flush = 1;
}
// avoid a continued page
if (!header && oggstream->page.size > 0 &&
MAX_PAGE_SIZE - oggstream->page.size < size) {
ogg_buffer_page(s, oggstream);
}
for (i = 0; i < total_segments; ) {
OGGPage *page = &oggstream->page;
segments = FFMIN(total_segments - i, 255 - page->segments_count);
if (i && !page->segments_count)
page->flags |= 1; // continued packet
memset(page->segments+page->segments_count, 255, segments - 1);
page->segments_count += segments - 1;
len = FFMIN(size, segments*255);
page->segments[page->segments_count++] = len - (segments-1)*255;
memcpy(page->data+page->size, p, len);
p += len;
size -= len;
i += segments;
page->size += len;
if (i == total_segments)
page->granule = granule;
if (!header) {
AVStream *st = s->streams[page->stream_index];
int64_t start = av_rescale_q(page->start_granule, st->time_base,
AV_TIME_BASE_Q);
int64_t next = av_rescale_q(page->granule, st->time_base,
AV_TIME_BASE_Q);
if (page->segments_count == 255 ||
(ogg->pref_size > 0 && page->size >= ogg->pref_size) ||
(ogg->pref_duration > 0 && next - start >= ogg->pref_duration)) {
ogg_buffer_page(s, oggstream);
}
}
}
if (flush && oggstream->page.granule != -1)
ogg_buffer_page(s, oggstream);
return 0;
}
static uint8_t *ogg_write_vorbiscomment(int offset, int bitexact,
int *header_len, AVDictionary **m, int framing_bit)
{
const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
int size;
uint8_t *p, *p0;
unsigned int count;
ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
size = offset + ff_vorbiscomment_length(*m, vendor, &count) + framing_bit;
p = av_mallocz(size);
if (!p)
return NULL;
p0 = p;
p += offset;
ff_vorbiscomment_write(&p, m, vendor, count);
if (framing_bit)
bytestream_put_byte(&p, 1);
*header_len = size;
return p0;
}
static int ogg_build_flac_headers(AVCodecContext *avctx,
OGGStreamContext *oggstream, int bitexact,
AVDictionary **m)
{
enum FLACExtradataFormat format;
uint8_t *streaminfo;
uint8_t *p;
if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))
return -1;
// first packet: STREAMINFO
oggstream->header_len[0] = 51;
oggstream->header[0] = av_mallocz(51); // per ogg flac specs
p = oggstream->header[0];
if (!p)
return AVERROR(ENOMEM);
bytestream_put_byte(&p, 0x7F);
bytestream_put_buffer(&p, "FLAC", 4);
bytestream_put_byte(&p, 1); // major version
bytestream_put_byte(&p, 0); // minor version
bytestream_put_be16(&p, 1); // headers packets without this one
bytestream_put_buffer(&p, "fLaC", 4);
bytestream_put_byte(&p, 0x00); // streaminfo
bytestream_put_be24(&p, 34);
bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE);
// second packet: VorbisComment
p = ogg_write_vorbiscomment(4, bitexact, &oggstream->header_len[1], m, 0);
if (!p)
return AVERROR(ENOMEM);
oggstream->header[1] = p;
bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment
bytestream_put_be24(&p, oggstream->header_len[1] - 4);
return 0;
}
#define SPEEX_HEADER_SIZE 80
static int ogg_build_speex_headers(AVCodecContext *avctx,
OGGStreamContext *oggstream, int bitexact,
AVDictionary **m)
{
uint8_t *p;
if (avctx->extradata_size < SPEEX_HEADER_SIZE)
return -1;
// first packet: Speex header
p = av_mallocz(SPEEX_HEADER_SIZE);
if (!p)
return AVERROR(ENOMEM);
oggstream->header[0] = p;
oggstream->header_len[0] = SPEEX_HEADER_SIZE;
bytestream_put_buffer(&p, avctx->extradata, SPEEX_HEADER_SIZE);
AV_WL32(&oggstream->header[0][68], 0); // set extra_headers to 0
// second packet: VorbisComment
p = ogg_write_vorbiscomment(0, bitexact, &oggstream->header_len[1], m, 0);
if (!p)
return AVERROR(ENOMEM);
oggstream->header[1] = p;
return 0;
}
#define OPUS_HEADER_SIZE 19
static int ogg_build_opus_headers(AVCodecContext *avctx,
OGGStreamContext *oggstream, int bitexact,
AVDictionary **m)
{
uint8_t *p;
if (avctx->extradata_size < OPUS_HEADER_SIZE)
return -1;
/* first packet: Opus header */
p = av_mallocz(avctx->extradata_size);
if (!p)
return AVERROR(ENOMEM);
oggstream->header[0] = p;
oggstream->header_len[0] = avctx->extradata_size;
bytestream_put_buffer(&p, avctx->extradata, avctx->extradata_size);
/* second packet: VorbisComment */
p = ogg_write_vorbiscomment(8, bitexact, &oggstream->header_len[1], m, 0);
if (!p)
return AVERROR(ENOMEM);
oggstream->header[1] = p;
bytestream_put_buffer(&p, "OpusTags", 8);
return 0;
}
static int ogg_write_header(AVFormatContext *s)
{
OGGContext *ogg = s->priv_data;
OGGStreamContext *oggstream = NULL;
int i, j;
if (ogg->pref_size)
av_log(s, AV_LOG_WARNING, "The pagesize option is deprecated\n");
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
unsigned serial_num = i;
if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
if (st->codec->codec_id == AV_CODEC_ID_OPUS)
/* Opus requires a fixed 48kHz clock */
avpriv_set_pts_info(st, 64, 1, 48000);
else
avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
} else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);
if (st->codec->codec_id != AV_CODEC_ID_VORBIS &&
st->codec->codec_id != AV_CODEC_ID_THEORA &&
st->codec->codec_id != AV_CODEC_ID_SPEEX &&
st->codec->codec_id != AV_CODEC_ID_FLAC &&
st->codec->codec_id != AV_CODEC_ID_OPUS) {
av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i);
return -1;
}
if (!st->codec->extradata || !st->codec->extradata_size) {
av_log(s, AV_LOG_ERROR, "No extradata present\n");
return -1;
}
oggstream = av_mallocz(sizeof(*oggstream));
oggstream->page.stream_index = i;
if (!(st->codec->flags & CODEC_FLAG_BITEXACT))
do {
serial_num = av_get_random_seed();
for (j = 0; j < i; j++) {
OGGStreamContext *sc = s->streams[j]->priv_data;
if (serial_num == sc->serial_num)
break;
}
} while (j < i);
oggstream->serial_num = serial_num;
av_dict_copy(&st->metadata, s->metadata, AV_DICT_DONT_OVERWRITE);
st->priv_data = oggstream;
if (st->codec->codec_id == AV_CODEC_ID_FLAC) {
int err = ogg_build_flac_headers(st->codec, oggstream,
st->codec->flags & CODEC_FLAG_BITEXACT,
&st->metadata);
if (err) {
av_log(s, AV_LOG_ERROR, "Error writing FLAC headers\n");
av_freep(&st->priv_data);
return err;
}
} else if (st->codec->codec_id == AV_CODEC_ID_SPEEX) {
int err = ogg_build_speex_headers(st->codec, oggstream,
st->codec->flags & CODEC_FLAG_BITEXACT,
&st->metadata);
if (err) {
av_log(s, AV_LOG_ERROR, "Error writing Speex headers\n");
av_freep(&st->priv_data);
return err;
}
} else if (st->codec->codec_id == AV_CODEC_ID_OPUS) {
int err = ogg_build_opus_headers(st->codec, oggstream,
st->codec->flags & CODEC_FLAG_BITEXACT,
&st->metadata);
if (err) {
av_log(s, AV_LOG_ERROR, "Error writing Opus headers\n");
av_freep(&st->priv_data);
return err;
}
} else {
uint8_t *p;
const char *cstr = st->codec->codec_id == AV_CODEC_ID_VORBIS ? "vorbis" : "theora";
int header_type = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 3 : 0x81;
int framing_bit = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 1 : 0;
if (avpriv_split_xiph_headers(st->codec->extradata, st->codec->extradata_size,
st->codec->codec_id == AV_CODEC_ID_VORBIS ? 30 : 42,
oggstream->header, oggstream->header_len) < 0) {
av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");
av_freep(&st->priv_data);
return -1;
}
p = ogg_write_vorbiscomment(7, st->codec->flags & CODEC_FLAG_BITEXACT,
&oggstream->header_len[1], &st->metadata,
framing_bit);
oggstream->header[1] = p;
if (!p)
return AVERROR(ENOMEM);
bytestream_put_byte(&p, header_type);
bytestream_put_buffer(&p, cstr, 6);
if (st->codec->codec_id == AV_CODEC_ID_THEORA) {
/** KFGSHIFT is the width of the less significant section of the granule position
The less significant section is the frame count since the last keyframe */
oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5);
oggstream->vrev = oggstream->header[0][9];
av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n",
oggstream->kfgshift, oggstream->vrev);
}
}
}
for (j = 0; j < s->nb_streams; j++) {
OGGStreamContext *oggstream = s->streams[j]->priv_data;
ogg_buffer_data(s, s->streams[j], oggstream->header[0],
oggstream->header_len[0], 0, 1);
oggstream->page.flags |= 2; // bos
ogg_buffer_page(s, oggstream);
}
for (j = 0; j < s->nb_streams; j++) {
AVStream *st = s->streams[j];
OGGStreamContext *oggstream = st->priv_data;
for (i = 1; i < 3; i++) {
if (oggstream->header_len[i])
ogg_buffer_data(s, st, oggstream->header[i],
oggstream->header_len[i], 0, 1);
}
ogg_buffer_page(s, oggstream);
}
oggstream->page.start_granule = AV_NOPTS_VALUE;
return 0;
}
static void ogg_write_pages(AVFormatContext *s, int flush)
{
OGGContext *ogg = s->priv_data;
OGGPageList *next, *p;
if (!ogg->page_list)
return;
for (p = ogg->page_list; p; ) {
OGGStreamContext *oggstream =
s->streams[p->page.stream_index]->priv_data;
if (oggstream->page_count < 2 && !flush)
break;
ogg_write_page(s, &p->page,
flush && oggstream->page_count == 1 ? 4 : 0); // eos
next = p->next;
av_freep(&p);
p = next;
}
ogg->page_list = p;
}
static int ogg_write_packet(AVFormatContext *s, AVPacket *pkt)
{
AVStream *st = s->streams[pkt->stream_index];
OGGStreamContext *oggstream = st->priv_data;
int ret;
int64_t granule;
if (st->codec->codec_id == AV_CODEC_ID_THEORA) {
int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration;
int pframe_count;
if (pkt->flags & AV_PKT_FLAG_KEY)
oggstream->last_kf_pts = pts;
pframe_count = pts - oggstream->last_kf_pts;
// prevent frame count from overflow if key frame flag is not set
if (pframe_count >= (1<<oggstream->kfgshift)) {
oggstream->last_kf_pts += pframe_count;
pframe_count = 0;
}
granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count;
} else if (st->codec->codec_id == AV_CODEC_ID_OPUS)
granule = pkt->pts + pkt->duration + av_rescale_q(st->codec->delay, (AVRational){ 1, st->codec->sample_rate }, st->time_base);
else
granule = pkt->pts + pkt->duration;
if (oggstream->page.start_granule == AV_NOPTS_VALUE)
oggstream->page.start_granule = pkt->pts;
ret = ogg_buffer_data(s, st, pkt->data, pkt->size, granule, 0);
if (ret < 0)
return ret;
ogg_write_pages(s, 0);
oggstream->last_granule = granule;
return 0;
}
static int ogg_write_trailer(AVFormatContext *s)
{
int i;
/* flush current page if needed */
for (i = 0; i < s->nb_streams; i++) {
OGGStreamContext *oggstream = s->streams[i]->priv_data;
if (oggstream->page.size > 0)
ogg_buffer_page(s, oggstream);
}
ogg_write_pages(s, 1);
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
OGGStreamContext *oggstream = st->priv_data;
if (st->codec->codec_id == AV_CODEC_ID_FLAC ||
st->codec->codec_id == AV_CODEC_ID_SPEEX ||
st->codec->codec_id == AV_CODEC_ID_OPUS) {
av_freep(&oggstream->header[0]);
}
av_freep(&oggstream->header[1]);
av_freep(&st->priv_data);
}
return 0;
}
#if CONFIG_OGG_MUXER
static const AVClass ogg_muxer_class = {
.class_name = "Ogg muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_ogg_muxer = {
.name = "ogg",
.long_name = NULL_IF_CONFIG_SMALL("Ogg"),
.mime_type = "application/ogg",
.extensions = "ogg,ogv"
#if !CONFIG_SPEEX_MUXER
",spx"
#endif
#if !CONFIG_OPUS_MUXER
",opus"
#endif
,
.priv_data_size = sizeof(OGGContext),
.audio_codec = CONFIG_LIBVORBIS_ENCODER ?
AV_CODEC_ID_VORBIS : AV_CODEC_ID_FLAC,
.video_codec = AV_CODEC_ID_THEORA,
.write_header = ogg_write_header,
.write_packet = ogg_write_packet,
.write_trailer = ogg_write_trailer,
.flags = AVFMT_TS_NEGATIVE,
.priv_class = &ogg_muxer_class,
};
#endif
#if CONFIG_OGA_MUXER
static const AVClass oga_muxer_class = {
.class_name = "Ogg audio muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_oga_muxer = {
.name = "oga",
.long_name = NULL_IF_CONFIG_SMALL("Ogg audio"),
.mime_type = "audio/ogg",
.extensions = "oga",
.priv_data_size = sizeof(OGGContext),
.audio_codec = AV_CODEC_ID_VORBIS,
.video_codec = AV_CODEC_ID_NONE,
.write_header = ogg_write_header,
.write_packet = ogg_write_packet,
.write_trailer = ogg_write_trailer,
.flags = AVFMT_TS_NEGATIVE,
.priv_class = &oga_muxer_class,
};
#endif
#if CONFIG_SPEEX_MUXER
static const AVClass speex_muxer_class = {
.class_name = "Speex muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_speex_muxer = {
.name = "speex",
.long_name = NULL_IF_CONFIG_SMALL("Speex"),
.mime_type = "audio/ogg",
.extensions = "spx",
.priv_data_size = sizeof(OGGContext),
.audio_codec = AV_CODEC_ID_SPEEX,
.video_codec = AV_CODEC_ID_NONE,
.write_header = ogg_write_header,
.write_packet = ogg_write_packet,
.write_trailer = ogg_write_trailer,
.flags = AVFMT_TS_NEGATIVE,
.priv_class = &speex_muxer_class,
};
#endif
#if CONFIG_OPUS_MUXER
static const AVClass opus_muxer_class = {
.class_name = "Opus muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_opus_muxer = {
.name = "opus",
.long_name = NULL_IF_CONFIG_SMALL("Opus"),
.mime_type = "audio/ogg",
.extensions = "opus",
.priv_data_size = sizeof(OGGContext),
.audio_codec = AV_CODEC_ID_OPUS,
.video_codec = AV_CODEC_ID_NONE,
.write_header = ogg_write_header,
.write_packet = ogg_write_packet,
.write_trailer = ogg_write_trailer,
.flags = AVFMT_TS_NEGATIVE,
.priv_class = &opus_muxer_class,
};
#endif