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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:336
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:2038
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3123
#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:4827
channels
Definition: aptx.c:30
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3876
Format I/O context.
Definition: avformat.h:1351
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:101
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:3913
#define AVINDEX_KEYFRAME
Definition: avformat.h:810
#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:1495
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define AVERROR(e)
Definition: error.h:43
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:1709
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
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:1541
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:874
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:1393
int64_t pts
Definition: voc.h:30
GLint GLenum type
Definition: opengl_enc.c:105
int sample_rate
Audio only.
Definition: avcodec.h:3994
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:754
Main libavformat public API header.
if(ret< 0)
Definition: vf_mcdeint.c:279
void * priv_data
Format private data.
Definition: avformat.h:1379
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:3926
int channels
Audio only.
Definition: avcodec.h:3990
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1429
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:762
This structure stores compressed data.
Definition: avcodec.h:1407
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1423
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248