ffmpeg/libavformat/soxenc.c
2023-08-15 21:42:21 +02:00

120 lines
3.8 KiB
C

/*
* SoX native format muxer
* Copyright (c) 2009 Daniel Verkamp <daniel@drv.nu>
*
* Based on libSoX sox-fmt.c
* Copyright (c) 2008 robs@users.sourceforge.net
*
* 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
* SoX native format muxer
* @author Daniel Verkamp
* @see http://wiki.multimedia.cx/index.php?title=SoX_native_intermediate_format
*/
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "libavutil/dict.h"
#include "avformat.h"
#include "avio_internal.h"
#include "mux.h"
#include "rawenc.h"
#include "sox.h"
typedef struct SoXContext {
int64_t header_size;
} SoXContext;
static int sox_write_header(AVFormatContext *s)
{
SoXContext *sox = s->priv_data;
AVIOContext *pb = s->pb;
AVCodecParameters *par = s->streams[0]->codecpar;
AVDictionaryEntry *comment;
size_t comment_len = 0, comment_size;
comment = av_dict_get(s->metadata, "comment", NULL, 0);
if (comment)
comment_len = strlen(comment->value);
comment_size = FFALIGN(comment_len, 8);
sox->header_size = SOX_FIXED_HDR + comment_size;
if (par->codec_id == AV_CODEC_ID_PCM_S32LE) {
ffio_wfourcc(pb, ".SoX");
avio_wl32(pb, sox->header_size);
avio_wl64(pb, 0); /* number of samples */
avio_wl64(pb, av_double2int(par->sample_rate));
avio_wl32(pb, par->ch_layout.nb_channels);
avio_wl32(pb, comment_size);
} else if (par->codec_id == AV_CODEC_ID_PCM_S32BE) {
ffio_wfourcc(pb, "XoS.");
avio_wb32(pb, sox->header_size);
avio_wb64(pb, 0); /* number of samples */
avio_wb64(pb, av_double2int(par->sample_rate));
avio_wb32(pb, par->ch_layout.nb_channels);
avio_wb32(pb, comment_size);
} else {
av_log(s, AV_LOG_ERROR, "invalid codec; use pcm_s32le or pcm_s32be\n");
return AVERROR(EINVAL);
}
if (comment_len)
avio_write(pb, comment->value, comment_len);
ffio_fill(pb, 0, comment_size - comment_len);
return 0;
}
static int sox_write_trailer(AVFormatContext *s)
{
SoXContext *sox = s->priv_data;
AVIOContext *pb = s->pb;
AVCodecParameters *par = s->streams[0]->codecpar;
if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
/* update number of samples */
int64_t file_size = avio_tell(pb);
int64_t num_samples = (file_size - sox->header_size - 4LL) >> 2LL;
avio_seek(pb, 8, SEEK_SET);
if (par->codec_id == AV_CODEC_ID_PCM_S32LE) {
avio_wl64(pb, num_samples);
} else
avio_wb64(pb, num_samples);
avio_seek(pb, file_size, SEEK_SET);
}
return 0;
}
const FFOutputFormat ff_sox_muxer = {
.p.name = "sox",
.p.long_name = NULL_IF_CONFIG_SMALL("SoX (Sound eXchange) native"),
.p.extensions = "sox",
.priv_data_size = sizeof(SoXContext),
.p.audio_codec = AV_CODEC_ID_PCM_S32LE,
.p.video_codec = AV_CODEC_ID_NONE,
.write_header = sox_write_header,
.write_packet = ff_raw_write_packet,
.write_trailer = sox_write_trailer,
.p.flags = AVFMT_NOTIMESTAMPS,
};