ffmpeg/libavformat/apc.c
Michael Niedermayer 1d9569f9e8 Merge remote-tracking branch 'qatar/master'
* qatar/master: (23 commits)
  aacenc: Fix identification padding when the bitstream is already aligned.
  aacenc: Write correct length for long identification strings.
  aud: remove unneeded field, audio_stream_index from context
  aud: fix time stamp calculation for ADPCM IMA WS
  aud: simplify header parsing
  aud: set pts_wrap_bits to 64.
  cosmetics: indentation
  aud: support Westwood SND1 audio in AUD files.
  adpcm_ima_ws: fix stereo decoding
  avcodec: add a new codec_id for CRYO APC IMA ADPCM.
  vqa: remove unused context fields, audio_samplerate and audio_bits
  vqa: clean up audio header parsing
  vqa: set time base to frame rate as coded in the header.
  vqa: set packet duration.
  vqa: use 1/sample_rate as the audio stream time base
  vqa: set stream start_time to 0.
  lavc: postpone the removal of AVCodecContext.request_channels.
  lavf: postpone removing av_close_input_file().
  lavc: postpone removing old audio encoding and decoding API
  avplay: remove the -er option.
  ...

Conflicts:
	Changelog
	libavcodec/version.h
	libavdevice/v4l.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-01-24 22:53:59 +01:00

90 lines
2.6 KiB
C

/*
* CRYO APC audio format demuxer
* Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
*
* 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 <string.h>
#include "avformat.h"
static int apc_probe(AVProbeData *p)
{
if (!strncmp(p->buf, "CRYO_APC", 8))
return AVPROBE_SCORE_MAX;
return 0;
}
static int apc_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVIOContext *pb = s->pb;
AVStream *st;
avio_rl32(pb); /* CRYO */
avio_rl32(pb); /* _APC */
avio_rl32(pb); /* 1.20 */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_ADPCM_IMA_APC;
avio_rl32(pb); /* number of samples */
st->codec->sample_rate = avio_rl32(pb);
st->codec->extradata_size = 2 * 4;
st->codec->extradata = av_malloc(st->codec->extradata_size +
FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata)
return AVERROR(ENOMEM);
/* initial predictor values for adpcm decoder */
avio_read(pb, st->codec->extradata, 2 * 4);
st->codec->channels = 1;
if (avio_rl32(pb))
st->codec->channels = 2;
st->codec->bits_per_coded_sample = 4;
st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels
* st->codec->sample_rate;
st->codec->block_align = 1;
return 0;
}
#define MAX_READ_SIZE 4096
static int apc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0)
return AVERROR(EIO);
pkt->stream_index = 0;
return 0;
}
AVInputFormat ff_apc_demuxer = {
.name = "apc",
.long_name = NULL_IF_CONFIG_SMALL("CRYO APC format"),
.read_probe = apc_probe,
.read_header = apc_read_header,
.read_packet = apc_read_packet,
};