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 "demux.h"
26 #include "riff.h"
27 #include "internal.h"
28 
29 #define CHUNK_SIZE 512
30 #define RIFF_TAG MKTAG('R','I','F','F')
31 #define WAVE_TAG MKTAG('W','A','V','E')
32 
33 typedef struct{
35  uint8_t audio_buffer[22];///< temporary buffer for ACT frame
36  char second_packet; ///< 1 - if temporary buffer contains valid (second) G.729 packet
37 } ACTContext;
38 
39 static int probe(const AVProbeData *p)
40 {
41  int i;
42 
43  if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
44  (AV_RL32(&p->buf[8]) != WAVE_TAG) ||
45  (AV_RL32(&p->buf[16]) != 16))
46  return 0;
47 
48  //We can't be sure that this is ACT and not regular WAV
49  if (p->buf_size<512)
50  return 0;
51 
52  for(i=44; i<256; i++)
53  if(p->buf[i])
54  return 0;
55 
56  if(p->buf[256]!=0x84)
57  return 0;
58 
59  for(i=264; i<512; i++)
60  if(p->buf[i])
61  return 0;
62 
63  return AVPROBE_SCORE_MAX;
64 }
65 
67 {
68  ACTContext* ctx = s->priv_data;
69  AVIOContext *pb = s->pb;
70  int size;
71  AVStream* st;
72  int ret;
73 
74  int min,sec,msec;
75 
76  st = avformat_new_stream(s, NULL);
77  if (!st)
78  return AVERROR(ENOMEM);
79 
80  avio_skip(pb, 16);
81  size=avio_rl32(pb);
82  ret = ff_get_wav_header(s, pb, st->codecpar, size, 0);
83  if (ret < 0)
84  return ret;
85 
86  /*
87  8000Hz (Fine-rec) file format has 10 bytes long
88  packets with 10ms of sound data in them
89  */
90  if (st->codecpar->sample_rate != 8000) {
91  av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codecpar->sample_rate);
92  return AVERROR_INVALIDDATA;
93  }
94 
95  st->codecpar->frame_size=80;
97  avpriv_set_pts_info(st, 64, 1, 100);
98 
100 
101  avio_seek(pb, 257, SEEK_SET);
102  msec=avio_rl16(pb);
103  sec=avio_r8(pb);
104  min=avio_rl32(pb);
105 
106  st->duration = av_rescale(1000*(min*60+sec)+msec, st->codecpar->sample_rate, 1000 * st->codecpar->frame_size);
107 
108  ctx->bytes_left_in_chunk=CHUNK_SIZE;
109 
110  avio_seek(pb, 512, SEEK_SET);
111 
112  return 0;
113 }
114 
115 
117  AVPacket *pkt)
118 {
119  ACTContext *ctx = s->priv_data;
120  AVIOContext *pb = s->pb;
121  int ret;
122  int frame_size=s->streams[0]->codecpar->sample_rate==8000?10:22;
123 
124 
125  if(s->streams[0]->codecpar->sample_rate==8000)
126  ret=av_new_packet(pkt, 10);
127  else
128  ret=av_new_packet(pkt, 11);
129 
130  if(ret)
131  return ret;
132 
133  if(s->streams[0]->codecpar->sample_rate==4400 && !ctx->second_packet)
134  {
135  ret = ffio_read_size(pb, ctx->audio_buffer, frame_size);
136 
137  if(ret<0)
138  return ret;
139 
140  pkt->data[0]=ctx->audio_buffer[11];
141  pkt->data[1]=ctx->audio_buffer[0];
142  pkt->data[2]=ctx->audio_buffer[12];
143  pkt->data[3]=ctx->audio_buffer[1];
144  pkt->data[4]=ctx->audio_buffer[13];
145  pkt->data[5]=ctx->audio_buffer[2];
146  pkt->data[6]=ctx->audio_buffer[14];
147  pkt->data[7]=ctx->audio_buffer[3];
148  pkt->data[8]=ctx->audio_buffer[15];
149  pkt->data[9]=ctx->audio_buffer[4];
150  pkt->data[10]=ctx->audio_buffer[16];
151 
152  ctx->second_packet=1;
153  }
154  else if(s->streams[0]->codecpar->sample_rate==4400 && ctx->second_packet)
155  {
156  pkt->data[0]=ctx->audio_buffer[5];
157  pkt->data[1]=ctx->audio_buffer[17];
158  pkt->data[2]=ctx->audio_buffer[6];
159  pkt->data[3]=ctx->audio_buffer[18];
160  pkt->data[4]=ctx->audio_buffer[7];
161  pkt->data[5]=ctx->audio_buffer[19];
162  pkt->data[6]=ctx->audio_buffer[8];
163  pkt->data[7]=ctx->audio_buffer[20];
164  pkt->data[8]=ctx->audio_buffer[9];
165  pkt->data[9]=ctx->audio_buffer[21];
166  pkt->data[10]=ctx->audio_buffer[10];
167 
168  ctx->second_packet=0;
169  }
170  else // 8000 Hz
171  {
172  ret = ffio_read_size(pb, ctx->audio_buffer, frame_size);
173 
174  if(ret<0)
175  return ret;
176 
177  pkt->data[0]=ctx->audio_buffer[5];
178  pkt->data[1]=ctx->audio_buffer[0];
179  pkt->data[2]=ctx->audio_buffer[6];
180  pkt->data[3]=ctx->audio_buffer[1];
181  pkt->data[4]=ctx->audio_buffer[7];
182  pkt->data[5]=ctx->audio_buffer[2];
183  pkt->data[6]=ctx->audio_buffer[8];
184  pkt->data[7]=ctx->audio_buffer[3];
185  pkt->data[8]=ctx->audio_buffer[9];
186  pkt->data[9]=ctx->audio_buffer[4];
187  }
188 
189  ctx->bytes_left_in_chunk -= frame_size;
190 
191  if(ctx->bytes_left_in_chunk < frame_size)
192  {
193  avio_skip(pb, ctx->bytes_left_in_chunk);
194  ctx->bytes_left_in_chunk=CHUNK_SIZE;
195  }
196 
197  pkt->duration=1;
198 
199  return ret;
200 }
201 
203  .p.name = "act",
204  .p.long_name = "ACT Voice file format",
205  .priv_data_size = sizeof(ACTContext),
206  .read_probe = probe,
209 };
read_header
static int read_header(AVFormatContext *s)
Definition: act.c:66
RIFF_TAG
#define RIFF_TAG
Definition: act.c:30
ACTContext::second_packet
char second_packet
1 - if temporary buffer contains valid (second) G.729 packet
Definition: act.c:36
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
WAVE_TAG
#define WAVE_TAG
Definition: act.c:31
ACTContext
Definition: act.c:33
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
CHUNK_SIZE
#define CHUNK_SIZE
Definition: act.c:29
ACTContext::bytes_left_in_chunk
int bytes_left_in_chunk
Definition: act.c:34
AVPacket::data
uint8_t * data
Definition: packet.h:522
ff_get_wav_header
int ff_get_wav_header(void *logctx, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:94
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:540
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
ff_act_demuxer
const FFInputFormat ff_act_demuxer
Definition: act.c:202
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
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:853
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:802
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:713
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
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:195
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
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:98
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
frame_size
int frame_size
Definition: mxfenc.c:2422
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: act.c:116
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:729
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
size
int size
Definition: twinvq_data.h:10344
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:602
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
avio_internal.h
demux.h
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:743
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:230
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:39
AV_CODEC_ID_G729
@ AV_CODEC_ID_G729
Definition: codec_id.h:493
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:317
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
riff.h
FFInputFormat
Definition: demux.h:37
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:661
min
float min
Definition: vorbis_enc_data.h:429