amr.c 4.55 KB
Newer Older
1
/*
kabi's avatar
kabi committed
2 3 4
 * amr file format
 * Copyright (c) 2001 ffmpeg project
 *
5 6 7
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
kabi's avatar
kabi committed
8 9
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
kabi's avatar
kabi committed
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
kabi's avatar
kabi committed
13 14 15 16 17
 * 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
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
kabi's avatar
kabi committed
20 21 22 23 24
 */

/*
Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267

25
Only mono files are supported.
kabi's avatar
kabi committed
26 27 28 29

*/
#include "avformat.h"

mru's avatar
mru committed
30 31
static const char AMR_header [] = "#!AMR\n";
static const char AMRWB_header [] = "#!AMR-WB\n";
kabi's avatar
kabi committed
32

33
#ifdef CONFIG_AMR_MUXER
kabi's avatar
kabi committed
34 35
static int amr_write_header(AVFormatContext *s)
{
36
    ByteIOContext *pb = s->pb;
37
    AVCodecContext *enc = s->streams[0]->codec;
kabi's avatar
kabi committed
38 39 40

    s->priv_data = NULL;

41 42 43 44 45 46 47 48 49 50
    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
    {
michael's avatar
michael committed
51
        return -1;
kabi's avatar
kabi committed
52 53 54 55 56
    }
    put_flush_packet(pb);
    return 0;
}

57
static int amr_write_packet(AVFormatContext *s, AVPacket *pkt)
kabi's avatar
kabi committed
58
{
59 60
    put_buffer(s->pb, pkt->data, pkt->size);
    put_flush_packet(s->pb);
kabi's avatar
kabi committed
61 62
    return 0;
}
63
#endif /* CONFIG_AMR_MUXER */
kabi's avatar
kabi committed
64 65 66

static int amr_probe(AVProbeData *p)
{
67 68
    //Only check for "#!AMR" which could be amr-wb, amr-nb.
    //This will also trigger multichannel files: "#!AMR_MC1.0\n" and
69 70 71
    //"#!AMR-WB_MC1.0\n" (not supported)

    if(memcmp(p->buf,AMR_header,5)==0)
kabi's avatar
kabi committed
72 73 74 75 76 77 78 79 80
        return AVPROBE_SCORE_MAX;
    else
        return 0;
}

/* amr input */
static int amr_read_header(AVFormatContext *s,
                           AVFormatParameters *ap)
{
81
    ByteIOContext *pb = s->pb;
kabi's avatar
kabi committed
82
    AVStream *st;
83
    uint8_t header[9];
kabi's avatar
kabi committed
84 85 86

    get_buffer(pb, header, 6);

87 88 89
    st = av_new_stream(s, 0);
    if (!st)
    {
90
        return AVERROR(ENOMEM);
91
    }
kabi's avatar
kabi committed
92 93
    if(memcmp(header,AMR_header,6)!=0)
    {
94 95 96 97 98
        get_buffer(pb, header+6, 3);
        if(memcmp(header,AMRWB_header,9)!=0)
        {
            return -1;
        }
99

100 101 102
        st->codec->codec_tag = MKTAG('s', 'a', 'w', 'b');
        st->codec->codec_id = CODEC_ID_AMR_WB;
        st->codec->sample_rate = 16000;
103 104 105
    }
    else
    {
106 107 108
        st->codec->codec_tag = MKTAG('s', 'a', 'm', 'r');
        st->codec->codec_id = CODEC_ID_AMR_NB;
        st->codec->sample_rate = 8000;
kabi's avatar
kabi committed
109
    }
michael's avatar
michael committed
110 111
    st->codec->channels = 1;
    st->codec->codec_type = CODEC_TYPE_AUDIO;
112
    av_set_pts_info(st, 64, 1, st->codec->sample_rate);
kabi's avatar
kabi committed
113 114 115 116 117 118 119

    return 0;
}

static int amr_read_packet(AVFormatContext *s,
                          AVPacket *pkt)
{
120
    AVCodecContext *enc = s->streams[0]->codec;
121
    int read, size = 0, toc, mode;
kabi's avatar
kabi committed
122

123
    if (url_feof(s->pb))
124
    {
125
        return AVERROR(EIO);
michael's avatar
michael committed
126
    }
127

128
//FIXME this is wrong, this should rather be in a AVParset
129
    toc=get_byte(s->pb);
michael's avatar
michael committed
130
    mode = (toc >> 3) & 0x0F;
131

michael's avatar
michael committed
132 133 134
    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};
135

michael's avatar
michael committed
136
        size=packed_size[mode]+1;
137 138 139 140
    }
    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};
141

michael's avatar
michael committed
142
        size=packed_size[mode];
143 144
    }
    else
kabi's avatar
kabi committed
145
    {
michael's avatar
michael committed
146
        assert(0);
kabi's avatar
kabi committed
147
    }
michael's avatar
michael committed
148 149 150

    if ( (size==0) || av_new_packet(pkt, size))
    {
151
        return AVERROR(EIO);
michael's avatar
michael committed
152 153 154
    }

    pkt->stream_index = 0;
155
    pkt->pos= url_ftell(s->pb);
michael's avatar
michael committed
156
    pkt->data[0]=toc;
157
    pkt->duration= enc->codec_id == CODEC_ID_AMR_NB ? 160 : 320;
158
    read = get_buffer(s->pb, pkt->data+1, size-1);
michael's avatar
michael committed
159 160 161 162

    if (read != size-1)
    {
        av_free_packet(pkt);
163
        return AVERROR(EIO);
michael's avatar
michael committed
164 165
    }

michael's avatar
michael committed
166
    return 0;
kabi's avatar
kabi committed
167 168
}

169 170
#ifdef CONFIG_AMR_DEMUXER
AVInputFormat amr_demuxer = {
kabi's avatar
kabi committed
171
    "amr",
172
    NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
173
    0, /*priv_data_size*/
kabi's avatar
kabi committed
174 175 176
    amr_probe,
    amr_read_header,
    amr_read_packet,
michael's avatar
michael committed
177
    NULL,
kabi's avatar
kabi committed
178
};
179
#endif
kabi's avatar
kabi committed
180

181 182
#ifdef CONFIG_AMR_MUXER
AVOutputFormat amr_muxer = {
kabi's avatar
kabi committed
183
    "amr",
184
    NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
kabi's avatar
kabi committed
185 186 187 188 189 190 191 192
    "audio/amr",
    "amr",
    0,
    CODEC_ID_AMR_NB,
    CODEC_ID_NONE,
    amr_write_header,
    amr_write_packet,
};
193
#endif