FFmpeg
act.c
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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 #include "avformat.h"
22 #include "riff.h"
23 #include "internal.h"
24 #include "libavcodec/get_bits.h"
25 
26 #define CHUNK_SIZE 512
27 #define RIFF_TAG MKTAG('R','I','F','F')
28 #define WAVE_TAG MKTAG('W','A','V','E')
29 
30 typedef struct{
32  uint8_t audio_buffer[22];///< temporary buffer for ACT frame
33  char second_packet; ///< 1 - if temporary buffer contains valid (second) G.729 packet
34 } ACTContext;
35 
36 static int probe(const AVProbeData *p)
37 {
38  int i;
39 
40  if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
41  (AV_RL32(&p->buf[8]) != WAVE_TAG) ||
42  (AV_RL32(&p->buf[16]) != 16))
43  return 0;
44 
45  //We can't be sure that this is ACT and not regular WAV
46  if (p->buf_size<512)
47  return 0;
48 
49  for(i=44; i<256; i++)
50  if(p->buf[i])
51  return 0;
52 
53  if(p->buf[256]!=0x84)
54  return 0;
55 
56  for(i=264; i<512; i++)
57  if(p->buf[i])
58  return 0;
59 
60  return AVPROBE_SCORE_MAX;
61 }
62 
64 {
65  ACTContext* ctx = s->priv_data;
66  AVIOContext *pb = s->pb;
67  int size;
68  AVStream* st;
69 
70  int min,sec,msec;
71 
72  st = avformat_new_stream(s, NULL);
73  if (!st)
74  return AVERROR(ENOMEM);
75 
76  avio_skip(pb, 16);
77  size=avio_rl32(pb);
78  ff_get_wav_header(s, pb, st->codecpar, size, 0);
79 
80  /*
81  8000Hz (Fine-rec) file format has 10 bytes long
82  packets with 10ms of sound data in them
83  */
84  if (st->codecpar->sample_rate != 8000) {
85  av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codecpar->sample_rate);
86  return AVERROR_INVALIDDATA;
87  }
88 
89  st->codecpar->frame_size=80;
90  st->codecpar->channels=1;
91  avpriv_set_pts_info(st, 64, 1, 100);
92 
94 
95  avio_seek(pb, 257, SEEK_SET);
96  msec=avio_rl16(pb);
97  sec=avio_r8(pb);
98  min=avio_rl32(pb);
99 
100  st->duration = av_rescale(1000*(min*60+sec)+msec, st->codecpar->sample_rate, 1000 * st->codecpar->frame_size);
101 
103 
104  avio_seek(pb, 512, SEEK_SET);
105 
106  return 0;
107 }
108 
109 
111  AVPacket *pkt)
112 {
113  ACTContext *ctx = s->priv_data;
114  AVIOContext *pb = s->pb;
115  int ret;
116  int frame_size=s->streams[0]->codecpar->sample_rate==8000?10:22;
117 
118 
119  if(s->streams[0]->codecpar->sample_rate==8000)
120  ret=av_new_packet(pkt, 10);
121  else
122  ret=av_new_packet(pkt, 11);
123 
124  if(ret)
125  return ret;
126 
127  if(s->streams[0]->codecpar->sample_rate==4400 && !ctx->second_packet)
128  {
129  ret = avio_read(pb, ctx->audio_buffer, frame_size);
130 
131  if(ret<0)
132  return ret;
133  if(ret!=frame_size)
134  return AVERROR(EIO);
135 
136  pkt->data[0]=ctx->audio_buffer[11];
137  pkt->data[1]=ctx->audio_buffer[0];
138  pkt->data[2]=ctx->audio_buffer[12];
139  pkt->data[3]=ctx->audio_buffer[1];
140  pkt->data[4]=ctx->audio_buffer[13];
141  pkt->data[5]=ctx->audio_buffer[2];
142  pkt->data[6]=ctx->audio_buffer[14];
143  pkt->data[7]=ctx->audio_buffer[3];
144  pkt->data[8]=ctx->audio_buffer[15];
145  pkt->data[9]=ctx->audio_buffer[4];
146  pkt->data[10]=ctx->audio_buffer[16];
147 
148  ctx->second_packet=1;
149  }
150  else if(s->streams[0]->codecpar->sample_rate==4400 && ctx->second_packet)
151  {
152  pkt->data[0]=ctx->audio_buffer[5];
153  pkt->data[1]=ctx->audio_buffer[17];
154  pkt->data[2]=ctx->audio_buffer[6];
155  pkt->data[3]=ctx->audio_buffer[18];
156  pkt->data[4]=ctx->audio_buffer[7];
157  pkt->data[5]=ctx->audio_buffer[19];
158  pkt->data[6]=ctx->audio_buffer[8];
159  pkt->data[7]=ctx->audio_buffer[20];
160  pkt->data[8]=ctx->audio_buffer[9];
161  pkt->data[9]=ctx->audio_buffer[21];
162  pkt->data[10]=ctx->audio_buffer[10];
163 
164  ctx->second_packet=0;
165  }
166  else // 8000 Hz
167  {
168  ret = avio_read(pb, ctx->audio_buffer, frame_size);
169 
170  if(ret<0)
171  return ret;
172  if(ret!=frame_size)
173  return AVERROR(EIO);
174 
175  pkt->data[0]=ctx->audio_buffer[5];
176  pkt->data[1]=ctx->audio_buffer[0];
177  pkt->data[2]=ctx->audio_buffer[6];
178  pkt->data[3]=ctx->audio_buffer[1];
179  pkt->data[4]=ctx->audio_buffer[7];
180  pkt->data[5]=ctx->audio_buffer[2];
181  pkt->data[6]=ctx->audio_buffer[8];
182  pkt->data[7]=ctx->audio_buffer[3];
183  pkt->data[8]=ctx->audio_buffer[9];
184  pkt->data[9]=ctx->audio_buffer[4];
185  }
186 
188 
189  if(ctx->bytes_left_in_chunk < frame_size)
190  {
191  avio_skip(pb, ctx->bytes_left_in_chunk);
193  }
194 
195  pkt->duration=1;
196 
197  return ret;
198 }
199 
201  .name = "act",
202  .long_name = "ACT Voice file format",
203  .priv_data_size = sizeof(ACTContext),
204  .read_probe = probe,
207 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
AVInputFormat ff_act_demuxer
Definition: act.c:200
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: act.c:110
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4882
int bytes_left_in_chunk
Definition: act.c:31
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
uint8_t audio_buffer[22]
temporary buffer for ACT frame
Definition: act.c:32
int frame_size
Audio only.
Definition: avcodec.h:4074
Format I/O context.
Definition: avformat.h:1358
uint8_t
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
uint8_t * data
Definition: avcodec.h:1477
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:100
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
int ff_get_wav_header(AVFormatContext *s, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:91
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define RIFF_TAG
Definition: act.c:27
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
#define WAVE_TAG
Definition: act.c:28
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:881
#define CHUNK_SIZE
Definition: act.c:26
int frame_size
Definition: mxfenc.c:2216
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static int read_header(AVFormatContext *s)
Definition: act.c:63
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
static int probe(const AVProbeData *p)
Definition: act.c:36
int sample_rate
Audio only.
Definition: avcodec.h:4063
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:754
Main libavformat public API header.
Definition: act.c:30
void * priv_data
Format private data.
Definition: avformat.h:1386
int channels
Audio only.
Definition: avcodec.h:4059
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
char second_packet
1 - if temporary buffer contains valid (second) G.729 packet
Definition: act.c:33
float min
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1454