oggparseogm.c
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1 
25 #include <stdlib.h>
26 #include "libavutil/intreadwrite.h"
27 #include "libavcodec/get_bits.h"
28 #include "libavcodec/bytestream.h"
29 #include "avformat.h"
30 #include "internal.h"
31 #include "oggdec.h"
32 #include "riff.h"
33 
34 static int
36 {
37  struct ogg *ogg = s->priv_data;
38  struct ogg_stream *os = ogg->streams + idx;
39  AVStream *st = s->streams[idx];
40  const uint8_t *p = os->buf + os->pstart;
41  uint64_t time_unit;
42  uint64_t spu;
43 
44  if(!(*p & 1))
45  return 0;
46 
47  if(*p == 1) {
48  p++;
49 
50  if(*p == 'v'){
51  int tag;
53  p += 8;
54  tag = bytestream_get_le32(&p);
56  st->codec->codec_tag = tag;
57  } else if (*p == 't') {
60  p += 12;
61  } else {
62  uint8_t acid[5];
63  int cid;
65  p += 8;
66  bytestream_get_buffer(&p, acid, 4);
67  acid[4] = 0;
68  cid = strtol(acid, NULL, 16);
71  }
72 
73  p += 4; /* useless size field */
74 
75  time_unit = bytestream_get_le64(&p);
76  spu = bytestream_get_le64(&p);
77  p += 4; /* default_len */
78  p += 8; /* buffersize + bits_per_sample */
79 
81  st->codec->width = bytestream_get_le32(&p);
82  st->codec->height = bytestream_get_le32(&p);
83  st->codec->time_base.den = spu * 10000000;
84  st->codec->time_base.num = time_unit;
86  } else {
87  st->codec->channels = bytestream_get_le16(&p);
88  p += 2; /* block_align */
89  st->codec->bit_rate = bytestream_get_le32(&p) * 8;
90  st->codec->sample_rate = spu * 10000000 / time_unit;
91  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
92  }
93  } else if (*p == 3) {
94  if (os->psize > 8)
95  ff_vorbis_comment(s, &st->metadata, p+7, os->psize-8);
96  }
97 
98  return 1;
99 }
100 
101 static int
103 {
104  struct ogg *ogg = s->priv_data;
105  struct ogg_stream *os = ogg->streams + idx;
106  AVStream *st = s->streams[idx];
107  uint8_t *p = os->buf + os->pstart;
108  uint32_t t;
109 
110  if(!(*p & 1))
111  return 0;
112  if(*p != 1)
113  return 1;
114 
115  t = AV_RL32(p + 96);
116 
117  if(t == 0x05589f80){
120  st->codec->time_base.den = 10000000;
121  st->codec->time_base.num = AV_RL64(p + 164);
122  st->codec->width = AV_RL32(p + 176);
123  st->codec->height = AV_RL32(p + 180);
124  } else if(t == 0x05589f81){
127  st->codec->channels = AV_RL16(p + 126);
128  st->codec->sample_rate = AV_RL32(p + 128);
129  st->codec->bit_rate = AV_RL32(p + 132) * 8;
130  }
131 
132  return 1;
133 }
134 
135 static int
137 {
138  struct ogg *ogg = s->priv_data;
139  struct ogg_stream *os = ogg->streams + idx;
140  uint8_t *p = os->buf + os->pstart;
141  int lb;
142 
143  if(*p & 8)
144  os->pflags |= AV_PKT_FLAG_KEY;
145 
146  lb = ((*p & 2) << 1) | ((*p >> 6) & 3);
147  os->pstart += lb + 1;
148  os->psize -= lb + 1;
149 
150  while (lb--)
151  os->pduration += p[lb+1] << (lb*8);
152 
153  return 0;
154 }
155 
157  .magic = "\001video",
158  .magicsize = 6,
159  .header = ogm_header,
160  .packet = ogm_packet,
161  .granule_is_start = 1,
162 };
163 
165  .magic = "\001audio",
166  .magicsize = 6,
167  .header = ogm_header,
168  .packet = ogm_packet,
169  .granule_is_start = 1,
170 };
171 
172 const struct ogg_codec ff_ogm_text_codec = {
173  .magic = "\001text",
174  .magicsize = 5,
175  .header = ogm_header,
176  .packet = ogm_packet,
177  .granule_is_start = 1,
178 };
179 
180 const struct ogg_codec ff_ogm_old_codec = {
181  .magic = "\001Direct Show Samples embedded in Ogg",
182  .magicsize = 35,
183  .header = ogm_dshow_header,
184  .packet = ogm_packet,
185  .granule_is_start = 1,
186 };