1 /*
2 * ACT file format demuxer
3 * Copyright (c) 2007-2008 Vladimir Voroshilov
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * 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
20 */
21
22 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "avio_internal.h"
25 #include "riff.h"
26 #include "internal.h"
27
28 #define CHUNK_SIZE 512
29 #define RIFF_TAG MKTAG('R','I','F','F')
30 #define WAVE_TAG MKTAG('W','A','V','E')
31
32 typedef struct{
33 int bytes_left_in_chunk;
34 uint8_t audio_buffer[22];///< temporary buffer for ACT frame
35 char second_packet; ///< 1 - if temporary buffer contains valid (second) G.729 packet
36 } ACTContext;
37
probe(const AVProbeData * p)38 static int probe(const AVProbeData *p)
39 {
40 int i;
41
42 if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
43 (AV_RL32(&p->buf[8]) != WAVE_TAG) ||
44 (AV_RL32(&p->buf[16]) != 16))
45 return 0;
46
47 //We can't be sure that this is ACT and not regular WAV
48 if (p->buf_size<512)
49 return 0;
50
51 for(i=44; i<256; i++)
52 if(p->buf[i])
53 return 0;
54
55 if(p->buf[256]!=0x84)
56 return 0;
57
58 for(i=264; i<512; i++)
59 if(p->buf[i])
60 return 0;
61
62 return AVPROBE_SCORE_MAX;
63 }
64
read_header(AVFormatContext * s)65 static int read_header(AVFormatContext *s)
66 {
67 ACTContext* ctx = s->priv_data;
68 AVIOContext *pb = s->pb;
69 int size;
70 AVStream* st;
71 int ret;
72
73 int min,sec,msec;
74
75 st = avformat_new_stream(s, NULL);
76 if (!st)
77 return AVERROR(ENOMEM);
78
79 avio_skip(pb, 16);
80 size=avio_rl32(pb);
81 ret = ff_get_wav_header(s, pb, st->codecpar, size, 0);
82 if (ret < 0)
83 return ret;
84
85 /*
86 8000Hz (Fine-rec) file format has 10 bytes long
87 packets with 10ms of sound data in them
88 */
89 if (st->codecpar->sample_rate != 8000) {
90 av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codecpar->sample_rate);
91 return AVERROR_INVALIDDATA;
92 }
93
94 st->codecpar->frame_size=80;
95 st->codecpar->ch_layout.nb_channels = 1;
96 avpriv_set_pts_info(st, 64, 1, 100);
97
98 st->codecpar->codec_id=AV_CODEC_ID_G729;
99
100 avio_seek(pb, 257, SEEK_SET);
101 msec=avio_rl16(pb);
102 sec=avio_r8(pb);
103 min=avio_rl32(pb);
104
105 st->duration = av_rescale(1000*(min*60+sec)+msec, st->codecpar->sample_rate, 1000 * st->codecpar->frame_size);
106
107 ctx->bytes_left_in_chunk=CHUNK_SIZE;
108
109 avio_seek(pb, 512, SEEK_SET);
110
111 return 0;
112 }
113
114
read_packet(AVFormatContext * s,AVPacket * pkt)115 static int read_packet(AVFormatContext *s,
116 AVPacket *pkt)
117 {
118 ACTContext *ctx = s->priv_data;
119 AVIOContext *pb = s->pb;
120 int ret;
121 int frame_size=s->streams[0]->codecpar->sample_rate==8000?10:22;
122
123
124 if(s->streams[0]->codecpar->sample_rate==8000)
125 ret=av_new_packet(pkt, 10);
126 else
127 ret=av_new_packet(pkt, 11);
128
129 if(ret)
130 return ret;
131
132 if(s->streams[0]->codecpar->sample_rate==4400 && !ctx->second_packet)
133 {
134 ret = ffio_read_size(pb, ctx->audio_buffer, frame_size);
135
136 if(ret<0)
137 return ret;
138
139 pkt->data[0]=ctx->audio_buffer[11];
140 pkt->data[1]=ctx->audio_buffer[0];
141 pkt->data[2]=ctx->audio_buffer[12];
142 pkt->data[3]=ctx->audio_buffer[1];
143 pkt->data[4]=ctx->audio_buffer[13];
144 pkt->data[5]=ctx->audio_buffer[2];
145 pkt->data[6]=ctx->audio_buffer[14];
146 pkt->data[7]=ctx->audio_buffer[3];
147 pkt->data[8]=ctx->audio_buffer[15];
148 pkt->data[9]=ctx->audio_buffer[4];
149 pkt->data[10]=ctx->audio_buffer[16];
150
151 ctx->second_packet=1;
152 }
153 else if(s->streams[0]->codecpar->sample_rate==4400 && ctx->second_packet)
154 {
155 pkt->data[0]=ctx->audio_buffer[5];
156 pkt->data[1]=ctx->audio_buffer[17];
157 pkt->data[2]=ctx->audio_buffer[6];
158 pkt->data[3]=ctx->audio_buffer[18];
159 pkt->data[4]=ctx->audio_buffer[7];
160 pkt->data[5]=ctx->audio_buffer[19];
161 pkt->data[6]=ctx->audio_buffer[8];
162 pkt->data[7]=ctx->audio_buffer[20];
163 pkt->data[8]=ctx->audio_buffer[9];
164 pkt->data[9]=ctx->audio_buffer[21];
165 pkt->data[10]=ctx->audio_buffer[10];
166
167 ctx->second_packet=0;
168 }
169 else // 8000 Hz
170 {
171 ret = ffio_read_size(pb, ctx->audio_buffer, frame_size);
172
173 if(ret<0)
174 return ret;
175
176 pkt->data[0]=ctx->audio_buffer[5];
177 pkt->data[1]=ctx->audio_buffer[0];
178 pkt->data[2]=ctx->audio_buffer[6];
179 pkt->data[3]=ctx->audio_buffer[1];
180 pkt->data[4]=ctx->audio_buffer[7];
181 pkt->data[5]=ctx->audio_buffer[2];
182 pkt->data[6]=ctx->audio_buffer[8];
183 pkt->data[7]=ctx->audio_buffer[3];
184 pkt->data[8]=ctx->audio_buffer[9];
185 pkt->data[9]=ctx->audio_buffer[4];
186 }
187
188 ctx->bytes_left_in_chunk -= frame_size;
189
190 if(ctx->bytes_left_in_chunk < frame_size)
191 {
192 avio_skip(pb, ctx->bytes_left_in_chunk);
193 ctx->bytes_left_in_chunk=CHUNK_SIZE;
194 }
195
196 pkt->duration=1;
197
198 return ret;
199 }
200
201 const AVInputFormat ff_act_demuxer = {
202 .name = "act",
203 .long_name = "ACT Voice file format",
204 .priv_data_size = sizeof(ACTContext),
205 .read_probe = probe,
206 .read_header = read_header,
207 .read_packet = read_packet,
208 };
209