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vocdec.c
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1 /*
2  * Creative Voice File demuxer.
3  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "voc.h"
24 #include "internal.h"
25 
26 int
28 {
29  VocDecContext *voc = s->priv_data;
30  AVCodecContext *dec = st->codec;
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)
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 (!dec->sample_rate) {
61  dec->sample_rate = 1000000 / (256 - avio_r8(pb));
62  if (sample_rate)
63  dec->sample_rate = sample_rate;
64  avpriv_set_pts_info(st, 64, 1, dec->sample_rate);
65  dec->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 (!dec->sample_rate) {
89  dec->sample_rate = avio_rl32(pb);
90  avpriv_set_pts_info(st, 64, 1, dec->sample_rate);
91  dec->bits_per_coded_sample = avio_r8(pb);
92  dec->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 (tmp_codec >= 0) {
110  tmp_codec = ff_codec_get_id(ff_voc_codec_tags, tmp_codec);
111  if (dec->codec_id == AV_CODEC_ID_NONE)
112  dec->codec_id = tmp_codec;
113  else if (dec->codec_id != tmp_codec)
114  av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n");
115  if (dec->codec_id == AV_CODEC_ID_NONE) {
116  if (s->audio_codec_id == AV_CODEC_ID_NONE) {
117  av_log(s, AV_LOG_ERROR, "unknown codec tag\n");
118  return AVERROR(EINVAL);
119  }
120  av_log(s, AV_LOG_WARNING, "unknown codec tag\n");
121  }
122  }
123 
124  dec->bit_rate = dec->sample_rate * dec->channels * dec->bits_per_coded_sample;
125 
126  if (max_size <= 0)
127  max_size = 2048;
128  size = FFMIN(voc->remaining_size, max_size);
129  voc->remaining_size -= size;
130 
131  ret = av_get_packet(pb, pkt, size);
132  pkt->dts = pkt->pts = voc->pts;
133 
134  duration = av_get_audio_frame_duration(st->codec, size);
135  if (duration > 0 && voc->pts != AV_NOPTS_VALUE)
136  voc->pts += duration;
137  else
138  voc->pts = AV_NOPTS_VALUE;
139 
140  return ret;
141 }
142 
143 #if CONFIG_VOC_DEMUXER
144 static int voc_probe(AVProbeData *p)
145 {
146  int version, check;
147 
148  if (memcmp(p->buf, ff_voc_magic, sizeof(ff_voc_magic) - 1))
149  return 0;
150  version = AV_RL16(p->buf + 22);
151  check = AV_RL16(p->buf + 24);
152  if (~version + 0x1234 != check)
153  return 10;
154 
155  return AVPROBE_SCORE_MAX;
156 }
157 
158 static int voc_read_header(AVFormatContext *s)
159 {
160  VocDecContext *voc = s->priv_data;
161  AVIOContext *pb = s->pb;
162  int header_size;
163  AVStream *st;
164 
165  avio_skip(pb, 20);
166  header_size = avio_rl16(pb) - 22;
167  if (header_size != 4) {
168  av_log(s, AV_LOG_ERROR, "unknown header size: %d\n", header_size);
169  return AVERROR(ENOSYS);
170  }
171  avio_skip(pb, header_size);
172  st = avformat_new_stream(s, NULL);
173  if (!st)
174  return AVERROR(ENOMEM);
176 
177  voc->remaining_size = 0;
178  return 0;
179 }
180 
181 static int voc_read_packet(AVFormatContext *s, AVPacket *pkt)
182 {
183  return ff_voc_get_packet(s, pkt, s->streams[0], 0);
184 }
185 
186 static int voc_read_seek(AVFormatContext *s, int stream_index,
187  int64_t timestamp, int flags)
188 {
189  VocDecContext *voc = s->priv_data;
190  AVStream *st = s->streams[stream_index];
191  int index = av_index_search_timestamp(st, timestamp, flags);
192 
193  if (index >= 0 && index < st->nb_index_entries - 1) {
194  AVIndexEntry *e = &st->index_entries[index];
195  avio_seek(s->pb, e->pos, SEEK_SET);
196  voc->pts = e->timestamp;
197  voc->remaining_size = e->size;
198  return 0;
199  } else if (st->nb_index_entries && st->index_entries[0].timestamp <= timestamp) {
200  AVIndexEntry *e = &st->index_entries[st->nb_index_entries - 1];
201  // prepare context for seek_frame_generic()
202  voc->pts = e->timestamp;
203  voc->remaining_size = e->size;
204  }
205  return -1;
206 }
207 
208 AVInputFormat ff_voc_demuxer = {
209  .name = "voc",
210  .long_name = NULL_IF_CONFIG_SMALL("Creative Voice"),
211  .priv_data_size = sizeof(VocDecContext),
212  .read_probe = voc_probe,
213  .read_header = voc_read_header,
214  .read_packet = voc_read_packet,
215  .read_seek = voc_read_seek,
216  .codec_tag = (const AVCodecTag* const []){ ff_voc_codec_tags, 0 },
217 };
218 #endif /* CONFIG_VOC_DEMUXER */
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:111
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:287
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:1778
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:2821
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1597
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:4149
int64_t pos
Definition: avformat.h:817
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:208
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1080
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:282
int version
Definition: avisynth_c.h:629
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
Format I/O context.
Definition: avformat.h:1314
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3805
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1382
#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:252
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:442
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2917
#define av_log(a,...)
#define AVINDEX_KEYFRAME
Definition: avformat.h:824
#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:3006
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1877
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:667
#define AVERROR(e)
Definition: error.h:43
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:818
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
VocType
Definition: voc.h:33
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:536
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:462
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:207
#define FFMIN(a, b)
Definition: common.h:96
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1480
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Definition: movenc-test.c:63
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
Stream structure.
Definition: avformat.h:877
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
sample_rate
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:27
enum AVMediaType codec_type
Definition: avcodec.h:1540
enum AVCodecID codec_id
Definition: avcodec.h:1549
int sample_rate
samples per second
Definition: avcodec.h:2287
AVIOContext * pb
I/O context.
Definition: avformat.h:1356
main external API structure.
Definition: avcodec.h:1532
int64_t pts
Definition: voc.h:30
GLint GLenum type
Definition: opengl_enc.c:105
int nb_index_entries
Definition: avformat.h:1082
int index
Definition: gxfenc.c:89
int ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
Definition: vocdec.c:27
This structure contains the data a format has to probe a file.
Definition: avformat.h:460
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:3024
const unsigned char ff_voc_magic[21]
Definition: voc.c:25
static int flags
Definition: cpu.c:47
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:472
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:651
int channels
number of audio channels
Definition: avcodec.h:2288
void * priv_data
Format private data.
Definition: avformat.h:1342
int64_t remaining_size
Definition: voc.h:29
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1466
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:659
This structure stores compressed data.
Definition: avcodec.h:1444
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1460
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240
#define check(x, y, S, v)