FFmpeg
mmf.c
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1 /*
2  * Yamaha SMAF format
3  * Copyright (c) 2005 Vidar Madsen
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 "config_components.h"
23 
25 #include "avformat.h"
26 #include "avio_internal.h"
27 #include "demux.h"
28 #include "internal.h"
29 #include "mux.h"
30 #include "pcm.h"
31 #include "rawenc.h"
32 #include "riff.h"
33 #include "version.h"
34 
35 typedef struct MMFContext {
38  int stereo;
39 } MMFContext;
40 
41 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
42 
43 static int mmf_rate(int code)
44 {
45  if ((code < 0) || (code > 4))
46  return -1;
47  return mmf_rates[code];
48 }
49 
50 #if CONFIG_MMF_MUXER
51 static int mmf_rate_code(int rate)
52 {
53  int i;
54  for (i = 0; i < 5; i++)
55  if (mmf_rates[i] == rate)
56  return i;
57  return -1;
58 }
59 
60 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
61 static void end_tag_be(AVIOContext *pb, int64_t start)
62 {
63  int64_t pos;
64 
65  pos = avio_tell(pb);
66  avio_seek(pb, start - 4, SEEK_SET);
67  avio_wb32(pb, (uint32_t)(pos - start));
68  avio_seek(pb, pos, SEEK_SET);
69 }
70 
71 static int mmf_write_header(AVFormatContext *s)
72 {
73  MMFContext *mmf = s->priv_data;
74  AVIOContext *pb = s->pb;
75  int64_t pos;
76  int rate;
77  const char *version = s->flags & AVFMT_FLAG_BITEXACT ?
78  "VN:Lavf," :
79  "VN:"LIBAVFORMAT_IDENT",";
80 
81  rate = mmf_rate_code(s->streams[0]->codecpar->sample_rate);
82  if (rate < 0) {
83  av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d, supported are 4000, 8000, 11025, 22050 and 44100\n",
84  s->streams[0]->codecpar->sample_rate);
85  return AVERROR(EINVAL);
86  }
87 
88  mmf->stereo = s->streams[0]->codecpar->ch_layout.nb_channels > 1;
89  if (mmf->stereo &&
90  s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
91  av_log(s, AV_LOG_ERROR, "Yamaha SMAF stereo is experimental, "
92  "add '-strict %d' if you want to use it.\n",
94  return AVERROR(EINVAL);
95  }
96 
97  ffio_wfourcc(pb, "MMMD");
98  avio_wb32(pb, 0);
99  pos = ff_start_tag(pb, "CNTI");
100  avio_w8(pb, 0); /* class */
101  avio_w8(pb, 1); /* type */
102  avio_w8(pb, 1); /* code type */
103  avio_w8(pb, 0); /* status */
104  avio_w8(pb, 0); /* counts */
105  end_tag_be(pb, pos);
106 
107  pos = ff_start_tag(pb, "OPDA");
108  avio_write(pb, version, strlen(version)); /* metadata ("ST:songtitle,VN:version,...") */
109  end_tag_be(pb, pos);
110 
111  avio_write(pb, "ATR\x00", 4);
112  avio_wb32(pb, 0);
113  mmf->atrpos = avio_tell(pb);
114  avio_w8(pb, 0); /* format type */
115  avio_w8(pb, 0); /* sequence type */
116  avio_w8(pb, (mmf->stereo << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
117  avio_w8(pb, 0); /* wave base bit */
118  avio_w8(pb, 2); /* time base d */
119  avio_w8(pb, 2); /* time base g */
120 
121  ffio_wfourcc(pb, "Atsq");
122  avio_wb32(pb, 16);
123  mmf->atsqpos = avio_tell(pb);
124  /* Will be filled on close */
125  avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
126 
127  mmf->awapos = ff_start_tag(pb, "Awa\x01");
128 
129  avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codecpar->sample_rate);
130 
131  return 0;
132 }
133 
134 /* Write a variable-length symbol */
135 static void put_varlength(AVIOContext *pb, int val)
136 {
137  if (val < 128)
138  avio_w8(pb, val);
139  else {
140  val -= 128;
141  avio_w8(pb, 0x80 | val >> 7);
142  avio_w8(pb, 0x7f & val);
143  }
144 }
145 
146 static int mmf_write_trailer(AVFormatContext *s)
147 {
148  AVIOContext *pb = s->pb;
149  MMFContext *mmf = s->priv_data;
150  int64_t pos, size;
151  int gatetime;
152 
153  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
154  /* Fill in length fields */
155  end_tag_be(pb, mmf->awapos);
156  end_tag_be(pb, mmf->atrpos);
157  end_tag_be(pb, 8);
158 
159  pos = avio_tell(pb);
160  size = pos - mmf->awapos;
161 
162  /* Fill Atsq chunk */
163  avio_seek(pb, mmf->atsqpos, SEEK_SET);
164 
165  /* "play wav" */
166  avio_w8(pb, 0); /* start time */
167  avio_w8(pb, (mmf->stereo << 6) | 1); /* (channel << 6) | wavenum */
168  gatetime = size * 500 / s->streams[0]->codecpar->sample_rate;
169  put_varlength(pb, gatetime); /* duration */
170 
171  /* "nop" */
172  put_varlength(pb, gatetime); /* start time */
173  avio_write(pb, "\xff\x00", 2); /* nop */
174 
175  /* "end of sequence" */
176  avio_write(pb, "\x00\x00\x00\x00", 4);
177 
178  avio_seek(pb, pos, SEEK_SET);
179  }
180  return 0;
181 }
182 #endif /* CONFIG_MMF_MUXER */
183 
184 static int mmf_probe(const AVProbeData *p)
185 {
186  /* check file header */
187  if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
188  p->buf[2] == 'M' && p->buf[3] == 'D' &&
189  p->buf[8] == 'C' && p->buf[9] == 'N' &&
190  p->buf[10] == 'T' && p->buf[11] == 'I')
191  return AVPROBE_SCORE_MAX;
192  else
193  return 0;
194 }
195 
196 /* mmf input */
198 {
199  MMFContext *mmf = s->priv_data;
200  unsigned int tag;
201  AVIOContext *pb = s->pb;
202  AVStream *st;
203  int64_t size;
204  int rate, params;
205 
206  tag = avio_rl32(pb);
207  if (tag != MKTAG('M', 'M', 'M', 'D'))
208  return AVERROR_INVALIDDATA;
209  avio_skip(pb, 4); /* file_size */
210 
211  /* Skip some unused chunks that may or may not be present */
212  for (;; avio_skip(pb, size)) {
213  tag = avio_rl32(pb);
214  size = avio_rb32(pb);
215  if (tag == MKTAG('C', 'N', 'T', 'I'))
216  continue;
217  if (tag == MKTAG('O', 'P', 'D', 'A'))
218  continue;
219  break;
220  }
221 
222  /* Tag = "ATRx", where "x" = track number */
223  if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
224  av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
225  return AVERROR_PATCHWELCOME;
226  }
227  if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
228  av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
229  return AVERROR_PATCHWELCOME;
230  }
231 
232  avio_r8(pb); /* format type */
233  avio_r8(pb); /* sequence type */
234  params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
235  rate = mmf_rate(params & 0x0f);
236  if (rate < 0) {
237  av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
238  return AVERROR_INVALIDDATA;
239  }
240  avio_r8(pb); /* wave base bit */
241  avio_r8(pb); /* time base d */
242  avio_r8(pb); /* time base g */
243 
244  /* Skip some unused chunks that may or may not be present */
245  for (;; avio_skip(pb, size)) {
246  tag = avio_rl32(pb);
247  size = avio_rb32(pb);
248  if (tag == MKTAG('A', 't', 's', 'q'))
249  continue;
250  if (tag == MKTAG('A', 's', 'p', 'I'))
251  continue;
252  break;
253  }
254 
255  /* Make sure it's followed by an Awa chunk, aka wave data */
256  if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
257  av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
258  return AVERROR_INVALIDDATA;
259  }
260  mmf->data_end = avio_tell(pb) + size;
261 
262  st = avformat_new_stream(s, NULL);
263  if (!st)
264  return AVERROR(ENOMEM);
265 
268  st->codecpar->sample_rate = rate;
269  av_channel_layout_default(&st->codecpar->ch_layout, (params >> 7) + 1);
271  st->codecpar->bit_rate = st->codecpar->sample_rate *
273 
274  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
275 
276  return 0;
277 }
278 
279 #define MAX_SIZE 4096
280 
282 {
283  MMFContext *mmf = s->priv_data;
284  int64_t left, size;
285  int ret;
286 
287  left = mmf->data_end - avio_tell(s->pb);
288  size = FFMIN(left, MAX_SIZE);
289  if (avio_feof(s->pb) || size <= 0)
290  return AVERROR_EOF;
291 
292  ret = av_get_packet(s->pb, pkt, size);
293  if (ret < 0)
294  return ret;
295 
296  pkt->stream_index = 0;
297 
298  return ret;
299 }
300 
301 #if CONFIG_MMF_DEMUXER
303  .p.name = "mmf",
304  .p.long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
305  .p.flags = AVFMT_GENERIC_INDEX,
306  .priv_data_size = sizeof(MMFContext),
310 };
311 #endif
312 
313 #if CONFIG_MMF_MUXER
315  .p.name = "mmf",
316  .p.long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
317  .p.mime_type = "application/vnd.smaf",
318  .p.extensions = "mmf",
319  .priv_data_size = sizeof(MMFContext),
320  .p.audio_codec = AV_CODEC_ID_ADPCM_YAMAHA,
321  .p.video_codec = AV_CODEC_ID_NONE,
322  .p.subtitle_codec = AV_CODEC_ID_NONE,
323  .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
325  .write_header = mmf_write_header,
326  .write_packet = ff_raw_write_packet,
327  .write_trailer = mmf_write_trailer,
328 };
329 #endif
LIBAVFORMAT_IDENT
#define LIBAVFORMAT_IDENT
Definition: version.h:45
AVOutputFormat::name
const char * name
Definition: avformat.h:510
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
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
ffio_wfourcc
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:124
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
MMFContext::stereo
int stereo
Definition: mmf.c:38
ff_mmf_demuxer
const FFInputFormat ff_mmf_demuxer
int64_t
long long int64_t
Definition: coverity.c:34
MMFContext::atrpos
int64_t atrpos
Definition: mmf.c:36
MMFContext::awapos
int64_t awapos
Definition: mmf.c:36
FF_COMPLIANCE_EXPERIMENTAL
#define FF_COMPLIANCE_EXPERIMENTAL
Allow nonstandardized experimental things.
Definition: defs.h:62
FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
#define FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
If this flag is set, then the only permitted audio/video/subtitle codec ids are AVOutputFormat....
Definition: mux.h:59
MAX_SIZE
#define MAX_SIZE
Definition: mmf.c:279
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
mmf_probe
static int mmf_probe(const AVProbeData *p)
Definition: mmf.c:184
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
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: avformat.c:855
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
val
static double val(void *priv, double ch)
Definition: aeval.c:78
MMFContext
Definition: mmf.c:35
ff_start_tag
int64_t ff_start_tag(AVIOContext *pb, const char *tag)
Definition: riffenc.c:31
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:761
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
MMFContext::data_end
int64_t data_end
Definition: mmf.c:37
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:31
ff_mmf_muxer
const FFOutputFormat ff_mmf_muxer
AVFormatContext
Format I/O context.
Definition: avformat.h:1260
mmf_rates
static const int mmf_rates[]
Definition: mmf.c:41
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:771
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
AV_CODEC_ID_ADPCM_YAMAHA
@ AV_CODEC_ID_ADPCM_YAMAHA
Definition: codec_id.h:381
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
FFOutputFormat
Definition: mux.h:61
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:179
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:730
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:94
mmf_rate
static int mmf_rate(int code)
Definition: mmf.c:43
size
int size
Definition: twinvq_data.h:10344
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:201
avio_wb32
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:365
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:603
version
version
Definition: libkvazaar.c:321
rawenc.h
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:834
mmf_read_header
static int mmf_read_header(AVFormatContext *s)
Definition: mmf.c:197
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
MMFContext::atsqpos
int64_t atsqpos
Definition: mmf.c:36
code
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
Definition: filter_design.txt:178
avio_internal.h
FF_OFMT_FLAG_MAX_ONE_OF_EACH
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
Definition: mux.h:50
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
demux.h
av_get_packet
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:91
version.h
tag
uint32_t tag
Definition: movenc.c:1873
ret
ret
Definition: filter_design.txt:187
AVFMT_FLAG_BITEXACT
#define AVFMT_FLAG_BITEXACT
When muxing, try to avoid writing any random/volatile data to the output.
Definition: avformat.h:1428
AVStream
Stream structure.
Definition: avformat.h:748
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:231
pos
unsigned int pos
Definition: spdifenc.c:414
avformat.h
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
channel_layout.h
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
AVPacket::stream_index
int stream_index
Definition: packet.h:535
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
mmf_read_packet
static int mmf_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mmf.c:281
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:510
riff.h
FFInputFormat
Definition: demux.h:37
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:346
mux.h