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 
153  duration = av_get_audio_frame_duration2(st->codecpar, size);
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 }
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:342
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: utils.c:2044
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3185
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
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:4999
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
GLint GLenum type
Definition: opengl_enc.c:104
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
AVPacket * pkt
Definition: movenc.c:59
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Format I/O context.
Definition: avformat.h:1247
int64_t duration
Definition: movenc.c:64
#define AVERROR_EOF
End of file.
Definition: error.h:55
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:310
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
channels
Definition: aptx.h:33
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
#define AVINDEX_KEYFRAME
Definition: avformat.h:820
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:613
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
VocType
Definition: voc.h:33
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:835
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
#define FFMIN(a, b)
Definition: common.h:105
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1441
#define s(width, name)
Definition: cbs_vp9.c:257
if(ret)
Stream structure.
Definition: avformat.h:884
int ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
Definition: voc_packet.c:27
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
sample_rate
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:27
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
int64_t pts
Definition: voc.h:30
int sample_rate
Audio only.
Definition: codec_par.h:170
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:734
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1275
int64_t remaining_size
Definition: voc.h:29
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
int channels
Audio only.
Definition: codec_par.h:166
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: packet.h:368
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:742
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
This structure stores compressed data.
Definition: packet.h:346
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248