/* * 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=3267Only mono files are supported.*/#include "avformat.h"static const char AMR_header [] = "#!AMR\n";static const char AMRWB_header [] = "#!AMR-WB\n";#ifdef CONFIG_MUXERSstatic int amr_write_header(AVFormatContext *s){    ByteIOContext *pb = s->pb;    AVCodecContext *enc = s->streams[0]->codec;    s->priv_data = NULL;    if (enc->codec_id == CODEC_ID_AMR_NB)    {        put_tag(pb, AMR_header);       /* magic number */    }    else if(enc->codec_id == CODEC_ID_AMR_WB)    {        put_tag(pb, AMRWB_header);       /* magic number */    }    else    {        return -1;    }    put_flush_packet(pb);    return 0;}static int amr_write_packet(AVFormatContext *s, AVPacket *pkt){    put_buffer(s->pb, pkt->data, pkt->size);    put_flush_packet(s->pb);    return 0;}#endif /* CONFIG_MUXERS */static int amr_probe(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" (not supported)    if(memcmp(p->buf,AMR_header,5)==0)        return AVPROBE_SCORE_MAX;    else        return 0;}/* amr input */static int amr_read_header(AVFormatContext *s,                           AVFormatParameters *ap){    ByteIOContext *pb = s->pb;    AVStream *st;    uint8_t header[9];    get_buffer(pb, header, 6);    st = av_new_stream(s, 0);    if (!st)    {        return AVERROR(ENOMEM);    }    if(memcmp(header,AMR_header,6)!=0)    {        get_buffer(pb, header+6, 3);        if(memcmp(header,AMRWB_header,9)!=0)        {            return -1;        }        st->codec->codec_tag = MKTAG('s', 'a', 'w', 'b');        st->codec->codec_id = CODEC_ID_AMR_WB;        st->codec->sample_rate = 16000;    }    else    {        st->codec->codec_tag = MKTAG('s', 'a', 'm', 'r');        st->codec->codec_id = CODEC_ID_AMR_NB;        st->codec->sample_rate = 8000;    }    st->codec->channels = 1;    st->codec->codec_type = CODEC_TYPE_AUDIO;    av_set_pts_info(st, 64, 1, st->codec->sample_rate);    return 0;}static int amr_read_packet(AVFormatContext *s,                          AVPacket *pkt){    AVCodecContext *enc = s->streams[0]->codec;    int read, size = 0, toc, mode;    if (url_feof(s->pb))    {        return AVERROR(EIO);    }//FIXME this is wrong, this should rather be in a AVParset    toc=get_byte(s->pb);    mode = (toc >> 3) & 0x0F;    if (enc->codec_id == CODEC_ID_AMR_NB)    {        static const uint8_t packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0};        size=packed_size[mode]+1;    }    else if(enc->codec_id == CODEC_ID_AMR_WB)    {        static uint8_t packed_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};        size=packed_size[mode];    }    else    {        assert(0);    }    if ( (size==0) || av_new_packet(pkt, size))    {        return AVERROR(EIO);    }    pkt->stream_index = 0;    pkt->pos= url_ftell(s->pb);    pkt->data[0]=toc;    pkt->duration= enc->codec_id == CODEC_ID_AMR_NB ? 160 : 320;    read = get_buffer(s->pb, pkt->data+1, size-1);    if (read != size-1)    {        av_free_packet(pkt);        return AVERROR(EIO);    }    return 0;}#ifdef CONFIG_AMR_DEMUXERAVInputFormat amr_demuxer = {    "amr",    NULL_IF_CONFIG_SMALL("3GPP AMR file format"),    0, /*priv_data_size*/    amr_probe,    amr_read_header,    amr_read_packet,    NULL,};#endif#ifdef CONFIG_AMR_MUXERAVOutputFormat amr_muxer = {    "amr",    NULL_IF_CONFIG_SMALL("3GPP AMR file format"),    "audio/amr",    "amr",    0,    CODEC_ID_AMR_NB,    CODEC_ID_NONE,    amr_write_header,    amr_write_packet,};#endif