FFmpeg  4.4
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->codecpar->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(&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->codecpar->width = get_bits(&gb, 16) << 4;
76  st->codecpar->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(&gb, 24);
83  int height = get_bits(&gb, 24);
84  if (width <= st->codecpar->width && width > st->codecpar->width - 16 &&
85  height <= st->codecpar->height && height > st->codecpar->height - 16) {
86  st->codecpar->width = width;
87  st->codecpar->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(&gb, 24);
103  st->sample_aspect_ratio.den = get_bits(&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 = (1U << 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->codecpar->extradata,
130  cds + AV_INPUT_BUFFER_PADDING_SIZE)) < 0) {
131  st->codecpar->extradata_size = 0;
132  return err;
133  }
134  memset(st->codecpar->extradata + cds, 0, AV_INPUT_BUFFER_PADDING_SIZE);
135 
136  cdp = st->codecpar->extradata + st->codecpar->extradata_size;
137  *cdp++ = os->psize >> 8;
138  *cdp++ = os->psize & 0xff;
139  memcpy(cdp, os->buf + os->pstart, os->psize);
140  st->codecpar->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  int64_t pts;
185 
186  duration = 1;
187  for (seg = os->segp; seg < os->nsegs; seg++) {
188  if (os->segments[seg] < 255)
189  duration ++;
190  }
191 
192  pts = theora_gptopts(s, idx, os->granule, NULL);
193  if (pts != AV_NOPTS_VALUE)
195  os->lastpts = os->lastdts = pts;
196  if(s->streams[idx]->start_time == AV_NOPTS_VALUE && os->lastpts != AV_NOPTS_VALUE) {
197  s->streams[idx]->start_time = os->lastpts;
198  if (s->streams[idx]->duration > 0)
199  s->streams[idx]->duration -= s->streams[idx]->start_time;
200  }
201  }
202 
203  /* parse packet duration */
204  if (os->psize > 0) {
205  os->pduration = 1;
206  }
207 
208  return 0;
209 }
210 
211 const struct ogg_codec ff_theora_codec = {
212  .magic = "\200theora",
213  .magicsize = 7,
214  .header = theora_header,
215  .packet = theora_packet,
216  .gptopts = theora_gptopts,
217  .nb_header = 3,
218 };
uint8_t
Main libavformat public API header.
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:795
byte swapping routines
#define s(width, name)
Definition: cbs_vp9.c:257
#define av_sat_sub64
Definition: common.h:167
#define NULL
Definition: coverity.c:32
bitstream reader API header.
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:546
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:291
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
@ AV_CODEC_ID_THEORA
Definition: codec_id.h:79
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding.
Definition: avcodec.h:215
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
int av_reallocp(void *ptr, size_t size)
Allocate, reallocate, or free a block of memory through a pointer to a pointer.
Definition: mem.c:161
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
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:4941
common internal API header
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
#define OGG_FLAG_EOS
Definition: oggdec.h:113
static int theora_packet(AVFormatContext *s, int idx)
static uint64_t theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp, int64_t *dts)
const struct ogg_codec ff_theora_codec
static int theora_header(AVFormatContext *s, int idx)
#define gp
Definition: regdef.h:62
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
int width
Video only.
Definition: codec_par.h:126
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
void * priv_data
Format private data.
Definition: avformat.h:1260
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int num
Numerator.
Definition: rational.h:59
int den
Denominator.
Definition: rational.h:60
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:935
enum AVStreamParseType need_parsing
Definition: avformat.h:1081
Copyright (C) 2005 Matthieu CASTET, Alex Beregszaszi.
unsigned version
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
const int8_t * magic
Definition: oggdec.h:32
unsigned int pduration
Definition: oggdec.h:68
unsigned int pflags
Definition: oggdec.h:67
int nsegs
Definition: oggdec.h:79
uint8_t segments[255]
Definition: oggdec.h:80
uint64_t granule
Definition: oggdec.h:70
int64_t lastdts
Definition: oggdec.h:73
unsigned int pstart
Definition: oggdec.h:65
unsigned int psize
Definition: oggdec.h:66
void * private
Definition: oggdec.h:91
uint8_t * buf
Definition: oggdec.h:62
int64_t lastpts
Definition: oggdec.h:72
int segp
Definition: oggdec.h:79
int flags
Definition: oggdec.h:76
Definition: oggdec.h:102
struct ogg_stream * streams
Definition: oggdec.h:103
#define av_log(a,...)
int64_t duration
Definition: movenc.c:64
AVFormatContext * ctx
Definition: movenc.c:48
#define height
#define width
static int64_t pts