FFmpeg
voc_packet.c
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1 /*
2  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/intreadwrite.h"
22 #include "avformat.h"
23 #include "internal.h"
24 #include "voc.h"
25 
26 int
28 {
29  VocDecContext *voc = s->priv_data;
30  AVCodecParameters *par = st->codecpar;
31  AVIOContext *pb = s->pb;
32  VocType type;
33  int size, tmp_codec=-1;
34  int sample_rate = 0;
35  int channels = 1;
36  int64_t duration;
37  int ret;
38 
40  avio_tell(pb),
41  voc->pts,
42  voc->remaining_size,
43  0,
45 
46  while (!voc->remaining_size) {
47  if (max_size < 4)
48  max_size = 0;
49  type = avio_r8(pb);
50  if (type == VOC_TYPE_EOF)
51  return AVERROR_EOF;
52  voc->remaining_size = avio_rl24(pb);
53  if (!voc->remaining_size) {
54  int64_t filesize;
55  if (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL))
56  return AVERROR(EIO);
57  filesize = avio_size(pb);
58  if (filesize - avio_tell(pb) > INT_MAX)
59  return AVERROR_INVALIDDATA;
60  voc->remaining_size = filesize - avio_tell(pb);
61  }
62  max_size -= 4;
63 
64  switch (type) {
66  if (voc->remaining_size < 2) {
67  voc->remaining_size = 0;
68  return AVERROR_INVALIDDATA;
69  }
70  if (!par->sample_rate) {
71  par->sample_rate = 1000000 / (256 - avio_r8(pb));
72  if (sample_rate)
73  par->sample_rate = sample_rate;
74  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
77  } else
78  avio_skip(pb, 1);
79  tmp_codec = avio_r8(pb);
80  voc->remaining_size -= 2;
81  max_size -= 2;
82  channels = 1;
83  break;
84 
86  break;
87 
88  case VOC_TYPE_EXTENDED:
89  sample_rate = avio_rl16(pb);
90  avio_r8(pb);
91  channels = avio_r8(pb) + 1;
92  sample_rate = 256000000 / (channels * (65536 - sample_rate));
93  voc->remaining_size = 0;
94  max_size -= 4;
95  break;
96 
98  if (voc->remaining_size < 12) {
99  voc->remaining_size = 0;
100  return AVERROR_INVALIDDATA;
101  }
102  if (!par->sample_rate) {
103  par->sample_rate = avio_rl32(pb);
104  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
105  par->bits_per_coded_sample = avio_r8(pb);
106  channels = avio_r8(pb);
108  } else
109  avio_skip(pb, 6);
110  tmp_codec = avio_rl16(pb);
111  avio_skip(pb, 4);
112  voc->remaining_size -= 12;
113  max_size -= 12;
114  break;
115 
116  default:
117  avio_skip(pb, voc->remaining_size);
118  max_size -= voc->remaining_size;
119  voc->remaining_size = 0;
120  break;
121  }
122  }
123 
124  if (par->sample_rate <= 0) {
125  av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);
126  return AVERROR_INVALIDDATA;
127  }
128 
129  if (tmp_codec >= 0) {
130  tmp_codec = ff_codec_get_id(ff_voc_codec_tags, tmp_codec);
131  if (par->codec_id == AV_CODEC_ID_NONE)
132  par->codec_id = tmp_codec;
133  else if (par->codec_id != tmp_codec)
134  av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n");
135  if (par->codec_id == AV_CODEC_ID_NONE) {
136  if (s->audio_codec_id == AV_CODEC_ID_NONE) {
137  av_log(s, AV_LOG_ERROR, "unknown codec tag\n");
138  return AVERROR(EINVAL);
139  }
140  av_log(s, AV_LOG_WARNING, "unknown codec tag\n");
141  }
142  }
143 
144  par->bit_rate = (int64_t)par->sample_rate * par->ch_layout.nb_channels * par->bits_per_coded_sample;
145 
146  if (max_size <= 0)
147  max_size = 2048;
148  size = FFMIN(voc->remaining_size, max_size);
149  voc->remaining_size -= size;
150 
151  ret = av_get_packet(pb, pkt, size);
152  pkt->dts = pkt->pts = voc->pts;
153 
155  if (duration > 0 && voc->pts != AV_NOPTS_VALUE)
156  voc->pts += duration;
157  else
158  voc->pts = AV_NOPTS_VALUE;
159 
160  return ret;
161 }
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
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
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:354
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:815
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
av_add_index_entry
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: seek.c:120
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:510
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:745
ff_voc_codec_tags
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:28
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:575
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
duration
int64_t duration
Definition: movenc.c:64
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
channels
channels
Definition: aptx.h:31
VOC_TYPE_VOICE_DATA
@ VOC_TYPE_VOICE_DATA
Definition: voc.h:35
if
if(ret)
Definition: filter_design.txt:179
AVFormatContext
Format I/O context.
Definition: avformat.h:1216
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
VOC_TYPE_EXTENDED
@ VOC_TYPE_EXTENDED
Definition: voc.h:42
VOC_TYPE_VOICE_DATA_CONT
@ VOC_TYPE_VOICE_DATA_CONT
Definition: voc.h:36
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:761
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:144
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
av_get_audio_frame_duration2
int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes)
This function is the same as av_get_audio_frame_duration(), except it works with AVCodecParameters in...
Definition: utils.c:826
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:373
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:634
VOC_TYPE_EOF
@ VOC_TYPE_EOF
Definition: voc.h:34
filesize
static int64_t filesize(AVIOContext *pb)
Definition: ffmpeg_mux.c:48
voc.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
avio_rl24
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:753
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:102
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:948
VOC_TYPE_NEW_VOICE_DATA
@ VOC_TYPE_NEW_VOICE_DATA
Definition: voc.h:43
avformat.h
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:349
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:104
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
ff_voc_get_packet
int ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
Definition: voc_packet.c:27
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:91
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