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oggparsetheora.c
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1 /**
2  * Copyright (C) 2005 Matthieu CASTET, Alex Beregszaszi
3  *
4  * Permission is hereby granted, free of charge, to any person
5  * obtaining a copy of this software and associated documentation
6  * files (the "Software"), to deal in the Software without
7  * restriction, including without limitation the rights to use, copy,
8  * modify, merge, publish, distribute, sublicense, and/or sell copies
9  * of the Software, and to permit persons to whom the Software is
10  * furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be
13  * included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  **/
24 
25 #include <stdlib.h>
26 #include "libavutil/bswap.h"
27 #include "libavcodec/get_bits.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "oggdec.h"
31 
32 typedef struct TheoraParams {
33  int gpshift;
34  int gpmask;
35  unsigned version;
36 } TheoraParams;
37 
38 static int theora_header(AVFormatContext *s, int idx)
39 {
40  struct ogg *ogg = s->priv_data;
41  struct ogg_stream *os = ogg->streams + idx;
42  AVStream *st = s->streams[idx];
43  TheoraParams *thp = os->private;
44  int cds = st->codec->extradata_size + os->psize + 2;
45  int err;
46  uint8_t *cdp;
47 
48  if (!(os->buf[os->pstart] & 0x80))
49  return 0;
50 
51  if (!thp) {
52  thp = av_mallocz(sizeof(*thp));
53  if (!thp)
54  return AVERROR(ENOMEM);
55  os->private = thp;
56  }
57 
58  switch (os->buf[os->pstart]) {
59  case 0x80: {
60  GetBitContext gb;
61  AVRational timebase;
62 
63  init_get_bits(&gb, os->buf + os->pstart, os->psize * 8);
64 
65  /* 0x80"theora" */
66  skip_bits_long(&gb, 7 * 8);
67 
68  thp->version = get_bits_long(&gb, 24);
69  if (thp->version < 0x030100) {
71  "Too old or unsupported Theora (%x)\n", thp->version);
72  return AVERROR(ENOSYS);
73  }
74 
75  st->codec->width = get_bits(&gb, 16) << 4;
76  st->codec->height = get_bits(&gb, 16) << 4;
77 
78  if (thp->version >= 0x030400)
79  skip_bits(&gb, 100);
80 
81  if (thp->version >= 0x030200) {
82  int width = get_bits_long(&gb, 24);
83  int height = get_bits_long(&gb, 24);
84  if (width <= st->codec->width && width > st->codec->width - 16 &&
85  height <= st->codec->height && height > st->codec->height - 16) {
86  st->codec->width = width;
87  st->codec->height = height;
88  }
89 
90  skip_bits(&gb, 16);
91  }
92 
93  timebase.den = get_bits_long(&gb, 32);
94  timebase.num = get_bits_long(&gb, 32);
95  if (!(timebase.num > 0 && timebase.den > 0)) {
96  av_log(s, AV_LOG_WARNING, "Invalid time base in theora stream, assuming 25 FPS\n");
97  timebase.num = 1;
98  timebase.den = 25;
99  }
100  avpriv_set_pts_info(st, 64, timebase.num, timebase.den);
101 
102  st->sample_aspect_ratio.num = get_bits_long(&gb, 24);
103  st->sample_aspect_ratio.den = get_bits_long(&gb, 24);
104 
105  if (thp->version >= 0x030200)
106  skip_bits_long(&gb, 38);
107  if (thp->version >= 0x304000)
108  skip_bits(&gb, 2);
109 
110  thp->gpshift = get_bits(&gb, 5);
111  thp->gpmask = (1 << thp->gpshift) - 1;
112 
116  }
117  break;
118  case 0x81:
119  ff_vorbis_stream_comment(s, st, os->buf + os->pstart + 7, os->psize - 7);
120  case 0x82:
121  if (!thp->version)
122  return AVERROR_INVALIDDATA;
123  break;
124  default:
125  av_log(s, AV_LOG_ERROR, "Unknown header type %X\n", os->buf[os->pstart]);
126  return AVERROR_INVALIDDATA;
127  }
128 
129  if ((err = av_reallocp(&st->codec->extradata,
130  cds + AV_INPUT_BUFFER_PADDING_SIZE)) < 0) {
131  st->codec->extradata_size = 0;
132  return err;
133  }
134  memset(st->codec->extradata + cds, 0, AV_INPUT_BUFFER_PADDING_SIZE);
135 
136  cdp = st->codec->extradata + st->codec->extradata_size;
137  *cdp++ = os->psize >> 8;
138  *cdp++ = os->psize & 0xff;
139  memcpy(cdp, os->buf + os->pstart, os->psize);
140  st->codec->extradata_size = cds;
141 
142  return 1;
143 }
144 
145 static uint64_t theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp,
146  int64_t *dts)
147 {
148  struct ogg *ogg = ctx->priv_data;
149  struct ogg_stream *os = ogg->streams + idx;
150  TheoraParams *thp = os->private;
151  uint64_t iframe, pframe;
152 
153  if (!thp)
154  return AV_NOPTS_VALUE;
155 
156  iframe = gp >> thp->gpshift;
157  pframe = gp & thp->gpmask;
158 
159  if (thp->version < 0x030201)
160  iframe++;
161 
162  if (!pframe)
163  os->pflags |= AV_PKT_FLAG_KEY;
164 
165  if (dts)
166  *dts = iframe + pframe;
167 
168  return iframe + pframe;
169 }
170 
171 static int theora_packet(AVFormatContext *s, int idx)
172 {
173  struct ogg *ogg = s->priv_data;
174  struct ogg_stream *os = ogg->streams + idx;
175  int duration;
176 
177  /* first packet handling
178  here we parse the duration of each packet in the first page and compare
179  the total duration to the page granule to find the encoder delay and
180  set the first timestamp */
181 
182  if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
183  int seg;
184 
185  duration = 1;
186  for (seg = os->segp; seg < os->nsegs; seg++) {
187  if (os->segments[seg] < 255)
188  duration ++;
189  }
190 
191  os->lastpts = os->lastdts = theora_gptopts(s, idx, os->granule, NULL) - duration;
192  if(s->streams[idx]->start_time == AV_NOPTS_VALUE) {
193  s->streams[idx]->start_time = os->lastpts;
194  if (s->streams[idx]->duration)
195  s->streams[idx]->duration -= s->streams[idx]->start_time;
196  }
197  }
198 
199  /* parse packet duration */
200  if (os->psize > 0) {
201  os->pduration = 1;
202  }
203 
204  return 0;
205 }
206 
207 const struct ogg_codec ff_theora_codec = {
208  .magic = "\200theora",
209  .magicsize = 7,
210  .header = theora_header,
211  .packet = theora_packet,
212  .gptopts = theora_gptopts,
213  .nb_header = 3,
214 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
unsigned int pflags
Definition: oggdec.h:67
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:260
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
static uint64_t theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp, int64_t *dts)
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:4071
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:217
const struct ogg_codec * codec
Definition: oggdec.h:77
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:914
int num
numerator
Definition: rational.h:44
int flags
Definition: oggdec.h:76
int64_t lastpts
Definition: oggdec.h:72
Format I/O context.
Definition: avformat.h:1272
unsigned int psize
Definition: oggdec.h:66
uint8_t
enum AVStreamParseType need_parsing
Definition: avformat.h:1035
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1616
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1340
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:187
bitstream reader API header.
static int64_t duration
Definition: ffplay.c:325
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1468
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
#define OGG_FLAG_EOS
Definition: oggdec.h:112
uint8_t segments[255]
Definition: oggdec.h:80
static int theora_packet(AVFormatContext *s, int idx)
Only parse headers, do not repack.
Definition: avformat.h:775
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
uint64_t granule
Definition: oggdec.h:70
int width
picture width / height.
Definition: avcodec.h:1680
unsigned int pstart
Definition: oggdec.h:65
struct ogg_stream * streams
Definition: oggdec.h:102
int segp
Definition: oggdec.h:79
Copyright (C) 2005 Matthieu CASTET, Alex Beregszaszi.
Stream structure.
Definition: avformat.h:842
enum AVMediaType codec_type
Definition: avcodec.h:1509
unsigned int pduration
Definition: oggdec.h:68
int nsegs
Definition: oggdec.h:79
enum AVCodecID codec_id
Definition: avcodec.h:1518
int extradata_size
Definition: avcodec.h:1617
void * private
Definition: oggdec.h:90
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:297
rational number numerator/denominator
Definition: rational.h:43
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:410
byte swapping routines
int64_t lastdts
Definition: oggdec.h:73
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:337
const int8_t * magic
Definition: oggdec.h:32
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:901
static int theora_header(AVFormatContext *s, int idx)
uint8_t * buf
Definition: oggdec.h:62
Main libavformat public API header.
unsigned version
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:894
int den
denominator
Definition: rational.h:45
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:635
Definition: oggdec.h:101
void * priv_data
Format private data.
Definition: avformat.h:1300
const struct ogg_codec ff_theora_codec
#define gp
Definition: regdef.h:62
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:252
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
static int width