FFmpeg/libavformat/nspdec.c
Paul B Mahol a41a5db797 avformat: add NSP demuxer
Signed-off-by: Paul B Mahol <onemda@gmail.com>
2017-12-08 16:01:09 +01:00

109 lines
3.3 KiB
C

/*
* NSP demuxer
* Copyright (c) 2017 Paul B Mahol
*
* 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 "libavutil/avstring.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#include "pcm.h"
static int nsp_probe(AVProbeData *p)
{
if (AV_RB32(p->buf) == AV_RB32("FORM") &&
AV_RB32(p->buf + 4) == AV_RB32("DS16"))
return AVPROBE_SCORE_MAX;
return 0;
}
static int nsp_read_header(AVFormatContext *s)
{
int channels = 0, rate = 0;
uint32_t chunk, size;
AVStream *st;
int64_t pos;
avio_skip(s->pb, 12);
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
while (!avio_feof(s->pb)) {
char value[1024];
chunk = avio_rb32(s->pb);
size = avio_rl32(s->pb);
pos = avio_tell(s->pb);
switch (chunk) {
case MKBETAG('H', 'E', 'D', 'R'):
case MKBETAG('H', 'D', 'R', '8'):
if (size < 32)
return AVERROR_INVALIDDATA;
avio_skip(s->pb, 20);
rate = avio_rl32(s->pb);
avio_skip(s->pb, size - (avio_tell(s->pb) - pos));
break;
case MKBETAG('N', 'O', 'T', 'E'):
avio_get_str(s->pb, size, value, sizeof(value));
av_dict_set(&s->metadata, "Comment", value, 0);
avio_skip(s->pb, size & 1);
break;
case MKBETAG('S', 'D', 'A', 'B'):
channels = 2;
break;
case MKBETAG('S', 'D', '_', '2'):
case MKBETAG('S', 'D', '_', '3'):
case MKBETAG('S', 'D', '_', '4'):
case MKBETAG('S', 'D', '_', '5'):
case MKBETAG('S', 'D', '_', '6'):
case MKBETAG('S', 'D', '_', '7'):
case MKBETAG('S', 'D', '_', '8'):
av_log(s, AV_LOG_WARNING, "Unsupported chunk!\n");
case MKBETAG('S', 'D', 'A', '_'):
case MKBETAG('S', 'D', '_', 'A'):
channels = 1;
break;
}
if (channels)
break;
}
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->channels = channels;
st->codecpar->sample_rate = rate;
st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
st->codecpar->block_align = 2 * channels;
return 0;
}
AVInputFormat ff_nsp_demuxer = {
.name = "nsp",
.long_name = NULL_IF_CONFIG_SMALL("Computerized Speech Lab NSP"),
.read_probe = nsp_probe,
.read_header = nsp_read_header,
.read_packet = ff_pcm_read_packet,
.read_seek = ff_pcm_read_seek,
.extensions = "nsp",
.flags = AVFMT_GENERIC_INDEX,
};