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/*
* ACT file format muxer/demuxer
* Copyright (c) 2007-2008 Vladimir Voroshilov
*
* 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 "avformat.h"
#include "riff.h"
#include "libavcodec/get_bits.h"
#define CHUNK_SIZE 512
#define RIFF_TAG MKTAG('R','I','F','F')
#define WAVE_TAG MKTAG('W','A','V','E')
typedef struct{
int bytes_left_in_chunk;
uint8_t audio_buffer[22];///< temporary buffer for ACT frame
char second_packet; ///< 1 - if temporary buffer contains valid (second) G.729 packet
} ACTContext;
static int probe(AVProbeData *p)
{
int i;
if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
(AV_RL32(&p->buf[8]) != WAVE_TAG) ||
(AV_RL32(&p->buf[16]) != 16))
return 0;
//We cant be sure that this is ACT and not regular WAV
if (p->buf_size<512)
return 0;
for(i=44; i<256; i++)
if(p->buf[i])
return 0;
if(p->buf[256]!=0x84)
return 0;
for(i=264; i<512; i++)
if(p->buf[i])
return 0;
return AVPROBE_SCORE_MAX;
}
static int read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
ACTContext* ctx = s->priv_data;
ByteIOContext *pb = s->pb;
int size;
AVStream* st;
int min,sec,msec;
st=av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
url_fskip(pb, 16);
size=get_le32(pb);
ff_get_wav_header(pb, st->codec, size);
/*
8000Hz (Fine-rec) file format has 10 bytes long
packets with 10ms of sound data in them
*/
if (st->codec->sample_rate != 8000) {
av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codec->sample_rate);
return AVERROR_INVALIDDATA;
}
st->codec->frame_size=80;
st->codec->channels=1;
av_set_pts_info(st, 64, 1, 100);
st->codec->codec_id=CODEC_ID_G729;
url_fseek(pb, 257, SEEK_SET);
msec=get_le16(pb);
sec=get_byte(pb);
min=get_le32(pb);
st->duration = av_rescale(1000*(min*60+sec)+msec, st->codec->sample_rate, 1000 * st->codec->frame_size);
ctx->bytes_left_in_chunk=CHUNK_SIZE;
url_fseek(pb, 512, SEEK_SET);
return 0;
}
static int read_packet(AVFormatContext *s,
AVPacket *pkt)
{
ACTContext *ctx = s->priv_data;
ByteIOContext *pb = s->pb;
int ret;
int frame_size=s->streams[0]->codec->sample_rate==8000?10:22;
if(s->streams[0]->codec->sample_rate==8000)
ret=av_new_packet(pkt, 10);
else
ret=av_new_packet(pkt, 11);
if(ret)
return ret;
if(s->streams[0]->codec->sample_rate==4400 && !ctx->second_packet)
{
ret = get_buffer(pb, ctx->audio_buffer, frame_size);
if(ret<0)
return ret;
if(ret!=frame_size)
return AVERROR(EIO);
pkt->data[0]=ctx->audio_buffer[11];
pkt->data[1]=ctx->audio_buffer[0];
pkt->data[2]=ctx->audio_buffer[12];
pkt->data[3]=ctx->audio_buffer[1];
pkt->data[4]=ctx->audio_buffer[13];
pkt->data[5]=ctx->audio_buffer[2];
pkt->data[6]=ctx->audio_buffer[14];
pkt->data[7]=ctx->audio_buffer[3];
pkt->data[8]=ctx->audio_buffer[15];
pkt->data[9]=ctx->audio_buffer[4];
pkt->data[10]=ctx->audio_buffer[16];
ctx->second_packet=1;
}
else if(s->streams[0]->codec->sample_rate==4400 && ctx->second_packet)
{
pkt->data[0]=ctx->audio_buffer[5];
pkt->data[1]=ctx->audio_buffer[17];
pkt->data[2]=ctx->audio_buffer[6];
pkt->data[3]=ctx->audio_buffer[18];
pkt->data[4]=ctx->audio_buffer[7];
pkt->data[5]=ctx->audio_buffer[19];
pkt->data[6]=ctx->audio_buffer[8];
pkt->data[7]=ctx->audio_buffer[20];
pkt->data[8]=ctx->audio_buffer[9];
pkt->data[9]=ctx->audio_buffer[21];
pkt->data[10]=ctx->audio_buffer[10];
ctx->second_packet=0;
}
else // 8000 Hz
{
ret = get_buffer(pb, ctx->audio_buffer, frame_size);
if(ret<0)
return ret;
if(ret!=frame_size)
return AVERROR(EIO);
pkt->data[0]=ctx->audio_buffer[5];
pkt->data[1]=ctx->audio_buffer[0];
pkt->data[2]=ctx->audio_buffer[6];
pkt->data[3]=ctx->audio_buffer[1];
pkt->data[4]=ctx->audio_buffer[7];
pkt->data[5]=ctx->audio_buffer[2];
pkt->data[6]=ctx->audio_buffer[8];
pkt->data[7]=ctx->audio_buffer[3];
pkt->data[8]=ctx->audio_buffer[9];
pkt->data[9]=ctx->audio_buffer[4];
}
ctx->bytes_left_in_chunk -= frame_size;
if(ctx->bytes_left_in_chunk < frame_size)
{
url_fskip(pb, ctx->bytes_left_in_chunk);
ctx->bytes_left_in_chunk=CHUNK_SIZE;
}
pkt->duration=1;
return ret;
}
AVInputFormat ff_act_demuxer = {
"act",
"ACT Voice file format",
sizeof(ACTContext),
probe,
read_header,
read_packet
};
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