FFmpeg
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 };
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:292
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
ogg_stream::segp
int segp
Definition: oggdec.h:79
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
ogg_stream::lastpts
int64_t lastpts
Definition: oggdec.h:72
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
TheoraParams
Copyright (C) 2005 Matthieu CASTET, Alex Beregszaszi.
Definition: oggparsetheora.c:32
get_bits_long
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:547
ogg_stream::granule
uint64_t granule
Definition: oggdec.h:70
TheoraParams::version
unsigned version
Definition: oggparsetheora.c:35
ogg_stream::buf
uint8_t * buf
Definition: oggdec.h:62
ogg_stream::nsegs
int nsegs
Definition: oggdec.h:79
ogg
Definition: oggdec.h:102
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:425
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:660
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:468
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:380
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:429
U
#define U(x)
Definition: vp56_arith.h:37
ogg_stream::lastdts
int64_t lastdts
Definition: oggdec.h:73
GetBitContext
Definition: get_bits.h:62
pts
static int64_t pts
Definition: transcode_aac.c:653
AVRational::num
int num
Numerator.
Definition: rational.h:59
ogg_stream::pstart
unsigned int pstart
Definition: oggdec.h:65
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
duration
int64_t duration
Definition: movenc.c:64
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
ctx
AVFormatContext * ctx
Definition: movenc.c:48
get_bits.h
theora_packet
static int theora_packet(AVFormatContext *s, int idx)
Definition: oggparsetheora.c:171
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:402
AVFormatContext
Format I/O context.
Definition: avformat.h:1109
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1004
NULL
#define NULL
Definition: coverity.c:32
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
ogg_stream::flags
int flags
Definition: oggdec.h:76
ogg::streams
struct ogg_stream * streams
Definition: oggdec.h:103
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
av_sat_sub64
#define av_sat_sub64
Definition: common.h:141
TheoraParams::gpmask
int gpmask
Definition: oggparsetheora.c:34
gp
#define gp
Definition: regdef.h:62
ogg_stream::private
void * private
Definition: oggdec.h:91
av_reallocp
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:185
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:913
height
#define height
ogg_stream::pflags
unsigned int pflags
Definition: oggdec.h:67
ogg_stream
Definition: oggdec.h:61
AV_CODEC_ID_THEORA
@ AV_CODEC_ID_THEORA
Definition: codec_id.h:80
AVCodecParameters::height
int height
Definition: codec_par.h:127
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:263
AVStream
Stream structure.
Definition: avformat.h:857
bswap.h
AVSTREAM_PARSE_HEADERS
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:781
avformat.h
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
oggdec.h
AVRational::den
int den
Denominator.
Definition: rational.h:60
ff_theora_codec
const struct ogg_codec ff_theora_codec
Definition: oggparsetheora.c:211
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, 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:1146
ff_vorbis_stream_comment
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
Parse Vorbis comments and add metadata to an AVStream.
Definition: oggparsevorbis.c:73
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ogg_stream::segments
uint8_t segments[255]
Definition: oggdec.h:80
OGG_FLAG_EOS
#define OGG_FLAG_EOS
Definition: oggdec.h:113
theora_header
static int theora_header(AVFormatContext *s, int idx)
Definition: oggparsetheora.c:38
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
ogg_stream::psize
unsigned int psize
Definition: oggdec.h:66
ogg_codec
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
theora_gptopts
static uint64_t theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp, int64_t *dts)
Definition: oggparsetheora.c:145
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ogg_codec::magic
const int8_t * magic
Definition: oggdec.h:32
ogg_stream::pduration
unsigned int pduration
Definition: oggdec.h:68
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1137
TheoraParams::gpshift
int gpshift
Definition: oggparsetheora.c:33