aboutsummaryrefslogtreecommitdiffstats
path: root/libavformat/act.c
blob: fba106c520f08c20699fb29ff2c196dabbd65547 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * ACT file format 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 "avio_internal.h"
#include "riff.h"
#include "internal.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(const 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 can't 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)
{
    ACTContext* ctx = s->priv_data;
    AVIOContext *pb = s->pb;
    int size;
    AVStream* st;

    int min,sec,msec;

    st = avformat_new_stream(s, NULL);
    if (!st)
        return AVERROR(ENOMEM);

    avio_skip(pb, 16);
    size=avio_rl32(pb);
    ff_get_wav_header(s, pb, st->codecpar, size, 0);

    /*
      8000Hz (Fine-rec) file format has 10 bytes long
      packets with 10ms of sound data in them
    */
    if (st->codecpar->sample_rate != 8000) {
        av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codecpar->sample_rate);
        return AVERROR_INVALIDDATA;
    }

    st->codecpar->frame_size=80;
    st->codecpar->ch_layout.nb_channels = 1;
    avpriv_set_pts_info(st, 64, 1, 100);

    st->codecpar->codec_id=AV_CODEC_ID_G729;

    avio_seek(pb, 257, SEEK_SET);
    msec=avio_rl16(pb);
    sec=avio_r8(pb);
    min=avio_rl32(pb);

    st->duration = av_rescale(1000*(min*60+sec)+msec, st->codecpar->sample_rate, 1000 * st->codecpar->frame_size);

    ctx->bytes_left_in_chunk=CHUNK_SIZE;

    avio_seek(pb, 512, SEEK_SET);

    return 0;
}


static int read_packet(AVFormatContext *s,
                          AVPacket *pkt)
{
    ACTContext *ctx = s->priv_data;
    AVIOContext *pb = s->pb;
    int ret;
    int frame_size=s->streams[0]->codecpar->sample_rate==8000?10:22;


    if(s->streams[0]->codecpar->sample_rate==8000)
        ret=av_new_packet(pkt, 10);
    else
        ret=av_new_packet(pkt, 11);

    if(ret)
        return ret;

    if(s->streams[0]->codecpar->sample_rate==4400 && !ctx->second_packet)
    {
        ret = ffio_read_size(pb, ctx->audio_buffer, frame_size);

        if(ret<0)
            return ret;

        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]->codecpar->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 = ffio_read_size(pb, ctx->audio_buffer, frame_size);

        if(ret<0)
            return ret;

        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)
    {
        avio_skip(pb, ctx->bytes_left_in_chunk);
        ctx->bytes_left_in_chunk=CHUNK_SIZE;
    }

    pkt->duration=1;

    return ret;
}

const AVInputFormat ff_act_demuxer = {
    .name           = "act",
    .long_name      = "ACT Voice file format",
    .priv_data_size = sizeof(ACTContext),
    .read_probe     = probe,
    .read_header    = read_header,
    .read_packet    = read_packet,
};