librempeg/libavformat/amr.c
2021-10-03 11:42:15 +02:00

285 lines
8.7 KiB
C

/*
* amr file format
* Copyright (c) 2001 FFmpeg project
*
* 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
*/
/*
Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267
*/
#include "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "avio_internal.h"
#include "internal.h"
#include "rawdec.h"
#include "rawenc.h"
typedef struct AMRContext {
FFRawDemuxerContext rawctx;
} AMRContext;
static const uint8_t AMR_header[6] = "#!AMR\x0a";
static const uint8_t AMRMC_header[12] = "#!AMR_MC1.0\x0a";
static const uint8_t AMRWB_header[9] = "#!AMR-WB\x0a";
static const uint8_t AMRWBMC_header[15] = "#!AMR-WB_MC1.0\x0a";
static const uint8_t amrnb_packed_size[16] = {
13, 14, 16, 18, 20, 21, 27, 32, 6, 1, 1, 1, 1, 1, 1, 1
};
static const uint8_t amrwb_packed_size[16] = {
18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 1, 1, 1, 1, 1, 1
};
#if CONFIG_AMR_MUXER
static int amr_write_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVCodecParameters *par = s->streams[0]->codecpar;
s->priv_data = NULL;
if (par->codec_id == AV_CODEC_ID_AMR_NB) {
avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
} else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
} else {
return -1;
}
return 0;
}
#endif /* CONFIG_AMR_MUXER */
static int amr_probe(const AVProbeData *p)
{
// Only check for "#!AMR" which could be amr-wb, amr-nb.
// This will also trigger multichannel files: "#!AMR_MC1.0\n" and
// "#!AMR-WB_MC1.0\n"
if (!memcmp(p->buf, AMR_header, 5))
return AVPROBE_SCORE_MAX;
else
return 0;
}
/* amr input */
static int amr_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVStream *st;
uint8_t header[19] = { 0 };
int read, back = 0, ret;
ret = ffio_ensure_seekback(s->pb, sizeof(header));
if (ret < 0)
return ret;
read = avio_read(pb, header, sizeof(header));
if (read < 0)
return ret;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
if (!memcmp(header, AMR_header, sizeof(AMR_header))) {
st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
st->codecpar->codec_id = AV_CODEC_ID_AMR_NB;
st->codecpar->sample_rate = 8000;
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
back = read - sizeof(AMR_header);
} else if (!memcmp(header, AMRWB_header, sizeof(AMRWB_header))) {
st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
st->codecpar->codec_id = AV_CODEC_ID_AMR_WB;
st->codecpar->sample_rate = 16000;
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
back = read - sizeof(AMRWB_header);
} else if (!memcmp(header, AMRMC_header, sizeof(AMRMC_header))) {
st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
st->codecpar->codec_id = AV_CODEC_ID_AMR_NB;
st->codecpar->sample_rate = 8000;
st->codecpar->channels = AV_RL32(header + 12);
back = read - 4 - sizeof(AMRMC_header);
} else if (!memcmp(header, AMRWBMC_header, sizeof(AMRWBMC_header))) {
st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
st->codecpar->codec_id = AV_CODEC_ID_AMR_WB;
st->codecpar->sample_rate = 16000;
st->codecpar->channels = AV_RL32(header + 15);
back = read - 4 - sizeof(AMRWBMC_header);
} else {
return AVERROR_INVALIDDATA;
}
if (st->codecpar->channels < 1)
return AVERROR_INVALIDDATA;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
if (back > 0)
avio_seek(pb, -back, SEEK_CUR);
return 0;
}
#if CONFIG_AMR_DEMUXER
const AVInputFormat ff_amr_demuxer = {
.name = "amr",
.long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
.priv_data_size = sizeof(AMRContext),
.read_probe = amr_probe,
.read_header = amr_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX,
.priv_class = &ff_raw_demuxer_class,
};
#endif
#if CONFIG_AMRNB_DEMUXER
static int amrnb_probe(const AVProbeData *p)
{
int mode, i = 0, valid = 0, invalid = 0;
const uint8_t *b = p->buf;
while (i < p->buf_size) {
mode = b[i] >> 3 & 0x0F;
if (mode < 9 && (b[i] & 0x4) == 0x4) {
int last = b[i];
int size = amrnb_packed_size[mode];
while (size--) {
if (b[++i] != last)
break;
}
if (size > 0) {
valid++;
i += size;
}
} else {
valid = 0;
invalid++;
i++;
}
}
if (valid > 100 && valid >> 4 > invalid)
return AVPROBE_SCORE_EXTENSION / 2 + 1;
return 0;
}
static int amrnb_read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_AMR_NB;
st->codecpar->sample_rate = 8000;
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
avpriv_set_pts_info(st, 64, 1, 8000);
return 0;
}
const AVInputFormat ff_amrnb_demuxer = {
.name = "amrnb",
.long_name = NULL_IF_CONFIG_SMALL("raw AMR-NB"),
.priv_data_size = sizeof(AMRContext),
.read_probe = amrnb_probe,
.read_header = amrnb_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX,
.priv_class = &ff_raw_demuxer_class,
};
#endif
#if CONFIG_AMRWB_DEMUXER
static int amrwb_probe(const AVProbeData *p)
{
int mode, i = 0, valid = 0, invalid = 0;
const uint8_t *b = p->buf;
while (i < p->buf_size) {
mode = b[i] >> 3 & 0x0F;
if (mode < 10 && (b[i] & 0x4) == 0x4) {
int last = b[i];
int size = amrwb_packed_size[mode];
while (size--) {
if (b[++i] != last)
break;
}
if (size > 0) {
valid++;
i += size;
}
} else {
valid = 0;
invalid++;
i++;
}
}
if (valid > 100 && valid >> 4 > invalid)
return AVPROBE_SCORE_EXTENSION / 2 + 1;
return 0;
}
static int amrwb_read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_AMR_WB;
st->codecpar->sample_rate = 16000;
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
avpriv_set_pts_info(st, 64, 1, 16000);
return 0;
}
const AVInputFormat ff_amrwb_demuxer = {
.name = "amrwb",
.long_name = NULL_IF_CONFIG_SMALL("raw AMR-WB"),
.priv_data_size = sizeof(AMRContext),
.read_probe = amrwb_probe,
.read_header = amrwb_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX,
.priv_class = &ff_raw_demuxer_class,
};
#endif
#if CONFIG_AMR_MUXER
const AVOutputFormat ff_amr_muxer = {
.name = "amr",
.long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
.mime_type = "audio/amr",
.extensions = "amr",
.audio_codec = AV_CODEC_ID_AMR_NB,
.video_codec = AV_CODEC_ID_NONE,
.write_header = amr_write_header,
.write_packet = ff_raw_write_packet,
.flags = AVFMT_NOTIMESTAMPS,
};
#endif