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 
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{
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 
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 
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;
96  avpriv_set_pts_info(st, 64, 1, 100);
97 
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 
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 
202  .name = "act",
203  .long_name = "ACT Voice file format",
204  .priv_data_size = sizeof(ACTContext),
205  .read_probe = probe,
208 };
read_header
static int read_header(AVFormatContext *s)
Definition: act.c:65
RIFF_TAG
#define RIFF_TAG
Definition: act.c:29
ACTContext::second_packet
char second_packet
1 - if temporary buffer contains valid (second) G.729 packet
Definition: act.c:35
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
WAVE_TAG
#define WAVE_TAG
Definition: act.c:30
ACTContext
Definition: act.c:32
CHUNK_SIZE
#define CHUNK_SIZE
Definition: act.c:28
ACTContext::bytes_left_in_chunk
int bytes_left_in_chunk
Definition: act.c:33
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:392
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:456
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:763
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:998
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:656
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:188
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
frame_size
int frame_size
Definition: mxfenc.c:2201
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: act.c:115
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
size
int size
Definition: twinvq_data.h:10344
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
avio_internal.h
ff_act_demuxer
const AVInputFormat ff_act_demuxer
Definition: act.c:201
ff_get_wav_header
int ff_get_wav_header(AVFormatContext *s, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:94
av_rescale
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
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
probe
static int probe(const AVProbeData *p)
Definition: act.c:38
AV_CODEC_ID_G729
@ AV_CODEC_ID_G729
Definition: codec_id.h:482
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
riff.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ffio_read_size
int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:691
min
float min
Definition: vorbis_enc_data.h:429