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  type = avio_r8(pb);
48  if (type == VOC_TYPE_EOF)
49  return AVERROR_EOF;
50  voc->remaining_size = avio_rl24(pb);
51  if (!voc->remaining_size) {
52  if (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL))
53  return AVERROR(EIO);
54  voc->remaining_size = avio_size(pb) - avio_tell(pb);
55  }
56  max_size -= 4;
57 
58  switch (type) {
60  if (!par->sample_rate) {
61  par->sample_rate = 1000000 / (256 - avio_r8(pb));
62  if (sample_rate)
63  par->sample_rate = sample_rate;
64  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
65  par->channels = channels;
67  } else
68  avio_skip(pb, 1);
69  tmp_codec = avio_r8(pb);
70  voc->remaining_size -= 2;
71  max_size -= 2;
72  channels = 1;
73  break;
74 
76  break;
77 
78  case VOC_TYPE_EXTENDED:
79  sample_rate = avio_rl16(pb);
80  avio_r8(pb);
81  channels = avio_r8(pb) + 1;
82  sample_rate = 256000000 / (channels * (65536 - sample_rate));
83  voc->remaining_size = 0;
84  max_size -= 4;
85  break;
86 
88  if (!par->sample_rate) {
89  par->sample_rate = avio_rl32(pb);
90  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
91  par->bits_per_coded_sample = avio_r8(pb);
92  par->channels = avio_r8(pb);
93  } else
94  avio_skip(pb, 6);
95  tmp_codec = avio_rl16(pb);
96  avio_skip(pb, 4);
97  voc->remaining_size -= 12;
98  max_size -= 12;
99  break;
100 
101  default:
102  avio_skip(pb, voc->remaining_size);
103  max_size -= voc->remaining_size;
104  voc->remaining_size = 0;
105  break;
106  }
107  }
108 
109  if (par->sample_rate <= 0) {
110  av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);
111  return AVERROR_INVALIDDATA;
112  }
113 
114  if (tmp_codec >= 0) {
115  tmp_codec = ff_codec_get_id(ff_voc_codec_tags, tmp_codec);
116  if (par->codec_id == AV_CODEC_ID_NONE)
117  par->codec_id = tmp_codec;
118  else if (par->codec_id != tmp_codec)
119  av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n");
120  if (par->codec_id == AV_CODEC_ID_NONE) {
121  if (s->audio_codec_id == AV_CODEC_ID_NONE) {
122  av_log(s, AV_LOG_ERROR, "unknown codec tag\n");
123  return AVERROR(EINVAL);
124  }
125  av_log(s, AV_LOG_WARNING, "unknown codec tag\n");
126  }
127  }
128 
129  par->bit_rate = (int64_t)par->sample_rate * par->channels * par->bits_per_coded_sample;
130 
131  if (max_size <= 0)
132  max_size = 2048;
133  size = FFMIN(voc->remaining_size, max_size);
134  voc->remaining_size -= size;
135 
136  ret = av_get_packet(pb, pkt, size);
137  pkt->dts = pkt->pts = voc->pts;
138 
139  duration = av_get_audio_frame_duration2(st->codecpar, size);
140  if (duration > 0 && voc->pts != AV_NOPTS_VALUE)
141  voc->pts += duration;
142  else
143  voc->pts = AV_NOPTS_VALUE;
144 
145  return ret;
146 }
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:339
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:2043
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3135
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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:4896
channels
Definition: aptx.c:30
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3960
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:334
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3952
Format I/O context.
Definition: avformat.h:1358
int64_t duration
Definition: movenc.c:63
#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
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3989
#define AVINDEX_KEYFRAME
Definition: avformat.h:817
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:1517
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
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:1730
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
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:96
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1550
#define s(width, name)
Definition: cbs_vp9.c:257
if(ret)
Stream structure.
Definition: avformat.h:881
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:1400
int64_t pts
Definition: voc.h:30
int sample_rate
Audio only.
Definition: avcodec.h:4070
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:756
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1386
int64_t remaining_size
Definition: voc.h:29
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4002
int channels
Audio only.
Definition: avcodec.h:4066
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1479
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:764
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: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248