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);
75  par->channels = channels;
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  par->channels = avio_r8(pb);
107  } else
108  avio_skip(pb, 6);
109  tmp_codec = avio_rl16(pb);
110  avio_skip(pb, 4);
111  voc->remaining_size -= 12;
112  max_size -= 12;
113  break;
114 
115  default:
116  avio_skip(pb, voc->remaining_size);
117  max_size -= voc->remaining_size;
118  voc->remaining_size = 0;
119  break;
120  }
121  }
122 
123  if (par->sample_rate <= 0) {
124  av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);
125  return AVERROR_INVALIDDATA;
126  }
127 
128  if (tmp_codec >= 0) {
129  tmp_codec = ff_codec_get_id(ff_voc_codec_tags, tmp_codec);
130  if (par->codec_id == AV_CODEC_ID_NONE)
131  par->codec_id = tmp_codec;
132  else if (par->codec_id != tmp_codec)
133  av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n");
134  if (par->codec_id == AV_CODEC_ID_NONE) {
135  if (s->audio_codec_id == AV_CODEC_ID_NONE) {
136  av_log(s, AV_LOG_ERROR, "unknown codec tag\n");
137  return AVERROR(EINVAL);
138  }
139  av_log(s, AV_LOG_WARNING, "unknown codec tag\n");
140  }
141  }
142 
143  par->bit_rate = (int64_t)par->sample_rate * par->channels * par->bits_per_coded_sample;
144 
145  if (max_size <= 0)
146  max_size = 2048;
147  size = FFMIN(voc->remaining_size, max_size);
148  voc->remaining_size -= size;
149 
150  ret = av_get_packet(pb, pkt, size);
151  pkt->dts = pkt->pts = voc->pts;
152 
154  if (duration > 0 && voc->pts != AV_NOPTS_VALUE)
155  voc->pts += duration;
156  else
157  voc->pts = AV_NOPTS_VALUE;
158 
159  return ret;
160 }
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:52
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:352
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:802
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:827
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
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:117
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:504
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:743
ff_voc_codec_tags
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:27
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:591
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:257
channels
channels
Definition: aptx.h:33
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:1193
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1088
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::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:358
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:372
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
VOC_TYPE_EOF
@ VOC_TYPE_EOF
Definition: voc.h:34
voc.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
avio_rl24
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:751
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:197
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:928
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:40
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: utils.c:1186
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
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:89
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61