f4167842c1
More exactly: Not more than one stream of each type for which a default codec (i.e. AVOutputFormat.(audio|video|subtitle)_codec) is set; for those types for which no such codec is set (or for which no designated default codec in AVOutputFormat exists at all) no streams are permitted. Given that with this flag set the default codecs become more important, they are now set explicitly to AV_CODEC_ID_NONE for "unset"; the earlier code relied on AV_CODEC_ID_NONE being equal to zero, so that default static initialization set it accordingly; but this is not how one is supposed to use an enum. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
105 lines
2.9 KiB
C
105 lines
2.9 KiB
C
/*
|
|
* Raw AC-4 muxer
|
|
*
|
|
* 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 "libavcodec/codec_id.h"
|
|
#include "libavcodec/codec_par.h"
|
|
#include "libavcodec/packet.h"
|
|
#include "libavutil/crc.h"
|
|
#include "libavutil/opt.h"
|
|
#include "avformat.h"
|
|
#include "mux.h"
|
|
|
|
typedef struct AC4Context {
|
|
AVClass *class;
|
|
int write_crc;
|
|
} AC4Context;
|
|
|
|
static int ac4_init(AVFormatContext *s)
|
|
{
|
|
AVCodecParameters *par = s->streams[0]->codecpar;
|
|
|
|
if (par->codec_id != AV_CODEC_ID_AC4) {
|
|
av_log(s, AV_LOG_ERROR, "Only one AC-4 stream can be muxed by the AC-4 muxer\n");
|
|
return AVERROR(EINVAL);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ac4_write_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
AC4Context *ac4 = s->priv_data;
|
|
AVIOContext *pb = s->pb;
|
|
|
|
if (!pkt->size)
|
|
return 0;
|
|
|
|
if (ac4->write_crc)
|
|
avio_wb16(pb, 0xAC41);
|
|
else
|
|
avio_wb16(pb, 0xAC40);
|
|
|
|
if (pkt->size >= 0xffff) {
|
|
avio_wb16(pb, 0xffff);
|
|
avio_wb24(pb, pkt->size);
|
|
} else {
|
|
avio_wb16(pb, pkt->size);
|
|
}
|
|
|
|
avio_write(pb, pkt->data, pkt->size);
|
|
|
|
if (ac4->write_crc) {
|
|
uint16_t crc = av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, pkt->data, pkt->size);
|
|
avio_wl16(pb, crc);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define ENC AV_OPT_FLAG_ENCODING_PARAM
|
|
#define OFFSET(obj) offsetof(AC4Context, obj)
|
|
static const AVOption ac4_options[] = {
|
|
{ "write_crc", "enable checksum", OFFSET(write_crc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
|
|
{ NULL },
|
|
};
|
|
|
|
static const AVClass ac4_muxer_class = {
|
|
.class_name = "AC4 muxer",
|
|
.item_name = av_default_item_name,
|
|
.option = ac4_options,
|
|
.version = LIBAVUTIL_VERSION_INT,
|
|
};
|
|
|
|
const FFOutputFormat ff_ac4_muxer = {
|
|
.p.name = "ac4",
|
|
.p.long_name = NULL_IF_CONFIG_SMALL("raw AC-4"),
|
|
.p.mime_type = "audio/ac4",
|
|
.p.extensions = "ac4",
|
|
.priv_data_size = sizeof(AC4Context),
|
|
.p.audio_codec = AV_CODEC_ID_AC4,
|
|
.p.video_codec = AV_CODEC_ID_NONE,
|
|
.p.subtitle_codec = AV_CODEC_ID_NONE,
|
|
.flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH,
|
|
.init = ac4_init,
|
|
.write_packet = ac4_write_packet,
|
|
.p.priv_class = &ac4_muxer_class,
|
|
.p.flags = AVFMT_NOTIMESTAMPS,
|
|
};
|