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 "internal.h"
28 #include "pcm.h"
29 #include "rawenc.h"
30 #include "riff.h"
31 #include "version.h"
32 
33 typedef struct MMFContext {
34  int64_t atrpos, atsqpos, awapos;
35  int64_t data_end;
36  int stereo;
37 } MMFContext;
38 
39 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
40 
41 static int mmf_rate(int code)
42 {
43  if ((code < 0) || (code > 4))
44  return -1;
45  return mmf_rates[code];
46 }
47 
48 #if CONFIG_MMF_MUXER
49 static int mmf_rate_code(int rate)
50 {
51  int i;
52  for (i = 0; i < 5; i++)
53  if (mmf_rates[i] == rate)
54  return i;
55  return -1;
56 }
57 
58 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
59 static void end_tag_be(AVIOContext *pb, int64_t start)
60 {
61  int64_t pos;
62 
63  pos = avio_tell(pb);
64  avio_seek(pb, start - 4, SEEK_SET);
65  avio_wb32(pb, (uint32_t)(pos - start));
66  avio_seek(pb, pos, SEEK_SET);
67 }
68 
69 static int mmf_write_header(AVFormatContext *s)
70 {
71  MMFContext *mmf = s->priv_data;
72  AVIOContext *pb = s->pb;
73  int64_t pos;
74  int rate;
75  const char *version = s->flags & AVFMT_FLAG_BITEXACT ?
76  "VN:Lavf," :
77  "VN:"LIBAVFORMAT_IDENT",";
78 
79  rate = mmf_rate_code(s->streams[0]->codecpar->sample_rate);
80  if (rate < 0) {
81  av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d, supported are 4000, 8000, 11025, 22050 and 44100\n",
82  s->streams[0]->codecpar->sample_rate);
83  return AVERROR(EINVAL);
84  }
85 
86  mmf->stereo = s->streams[0]->codecpar->ch_layout.nb_channels > 1;
87  if (mmf->stereo &&
88  s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
89  av_log(s, AV_LOG_ERROR, "Yamaha SMAF stereo is experimental, "
90  "add '-strict %d' if you want to use it.\n",
92  return AVERROR(EINVAL);
93  }
94 
95  ffio_wfourcc(pb, "MMMD");
96  avio_wb32(pb, 0);
97  pos = ff_start_tag(pb, "CNTI");
98  avio_w8(pb, 0); /* class */
99  avio_w8(pb, 1); /* type */
100  avio_w8(pb, 1); /* code type */
101  avio_w8(pb, 0); /* status */
102  avio_w8(pb, 0); /* counts */
103  end_tag_be(pb, pos);
104 
105  pos = ff_start_tag(pb, "OPDA");
106  avio_write(pb, version, strlen(version)); /* metadata ("ST:songtitle,VN:version,...") */
107  end_tag_be(pb, pos);
108 
109  avio_write(pb, "ATR\x00", 4);
110  avio_wb32(pb, 0);
111  mmf->atrpos = avio_tell(pb);
112  avio_w8(pb, 0); /* format type */
113  avio_w8(pb, 0); /* sequence type */
114  avio_w8(pb, (mmf->stereo << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
115  avio_w8(pb, 0); /* wave base bit */
116  avio_w8(pb, 2); /* time base d */
117  avio_w8(pb, 2); /* time base g */
118 
119  ffio_wfourcc(pb, "Atsq");
120  avio_wb32(pb, 16);
121  mmf->atsqpos = avio_tell(pb);
122  /* Will be filled on close */
123  avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
124 
125  mmf->awapos = ff_start_tag(pb, "Awa\x01");
126 
127  avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codecpar->sample_rate);
128 
129  return 0;
130 }
131 
132 /* Write a variable-length symbol */
133 static void put_varlength(AVIOContext *pb, int val)
134 {
135  if (val < 128)
136  avio_w8(pb, val);
137  else {
138  val -= 128;
139  avio_w8(pb, 0x80 | val >> 7);
140  avio_w8(pb, 0x7f & val);
141  }
142 }
143 
144 static int mmf_write_trailer(AVFormatContext *s)
145 {
146  AVIOContext *pb = s->pb;
147  MMFContext *mmf = s->priv_data;
148  int64_t pos, size;
149  int gatetime;
150 
151  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
152  /* Fill in length fields */
153  end_tag_be(pb, mmf->awapos);
154  end_tag_be(pb, mmf->atrpos);
155  end_tag_be(pb, 8);
156 
157  pos = avio_tell(pb);
158  size = pos - mmf->awapos;
159 
160  /* Fill Atsq chunk */
161  avio_seek(pb, mmf->atsqpos, SEEK_SET);
162 
163  /* "play wav" */
164  avio_w8(pb, 0); /* start time */
165  avio_w8(pb, (mmf->stereo << 6) | 1); /* (channel << 6) | wavenum */
166  gatetime = size * 500 / s->streams[0]->codecpar->sample_rate;
167  put_varlength(pb, gatetime); /* duration */
168 
169  /* "nop" */
170  put_varlength(pb, gatetime); /* start time */
171  avio_write(pb, "\xff\x00", 2); /* nop */
172 
173  /* "end of sequence" */
174  avio_write(pb, "\x00\x00\x00\x00", 4);
175 
176  avio_seek(pb, pos, SEEK_SET);
177  }
178  return 0;
179 }
180 #endif /* CONFIG_MMF_MUXER */
181 
182 static int mmf_probe(const AVProbeData *p)
183 {
184  /* check file header */
185  if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
186  p->buf[2] == 'M' && p->buf[3] == 'D' &&
187  p->buf[8] == 'C' && p->buf[9] == 'N' &&
188  p->buf[10] == 'T' && p->buf[11] == 'I')
189  return AVPROBE_SCORE_MAX;
190  else
191  return 0;
192 }
193 
194 /* mmf input */
196 {
197  MMFContext *mmf = s->priv_data;
198  unsigned int tag;
199  AVIOContext *pb = s->pb;
200  AVStream *st;
201  int64_t size;
202  int rate, params;
203 
204  tag = avio_rl32(pb);
205  if (tag != MKTAG('M', 'M', 'M', 'D'))
206  return AVERROR_INVALIDDATA;
207  avio_skip(pb, 4); /* file_size */
208 
209  /* Skip some unused chunks that may or may not be present */
210  for (;; avio_skip(pb, size)) {
211  tag = avio_rl32(pb);
212  size = avio_rb32(pb);
213  if (tag == MKTAG('C', 'N', 'T', 'I'))
214  continue;
215  if (tag == MKTAG('O', 'P', 'D', 'A'))
216  continue;
217  break;
218  }
219 
220  /* Tag = "ATRx", where "x" = track number */
221  if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
222  av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
223  return AVERROR_PATCHWELCOME;
224  }
225  if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
226  av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
227  return AVERROR_PATCHWELCOME;
228  }
229 
230  avio_r8(pb); /* format type */
231  avio_r8(pb); /* sequence type */
232  params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
233  rate = mmf_rate(params & 0x0f);
234  if (rate < 0) {
235  av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
236  return AVERROR_INVALIDDATA;
237  }
238  avio_r8(pb); /* wave base bit */
239  avio_r8(pb); /* time base d */
240  avio_r8(pb); /* time base g */
241 
242  /* Skip some unused chunks that may or may not be present */
243  for (;; avio_skip(pb, size)) {
244  tag = avio_rl32(pb);
245  size = avio_rb32(pb);
246  if (tag == MKTAG('A', 't', 's', 'q'))
247  continue;
248  if (tag == MKTAG('A', 's', 'p', 'I'))
249  continue;
250  break;
251  }
252 
253  /* Make sure it's followed by an Awa chunk, aka wave data */
254  if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
255  av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
256  return AVERROR_INVALIDDATA;
257  }
258  mmf->data_end = avio_tell(pb) + size;
259 
260  st = avformat_new_stream(s, NULL);
261  if (!st)
262  return AVERROR(ENOMEM);
263 
266  st->codecpar->sample_rate = rate;
267  av_channel_layout_default(&st->codecpar->ch_layout, (params >> 7) + 1);
269  st->codecpar->bit_rate = st->codecpar->sample_rate *
271 
272  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
273 
274  return 0;
275 }
276 
277 #define MAX_SIZE 4096
278 
280 {
281  MMFContext *mmf = s->priv_data;
282  int64_t left, size;
283  int ret;
284 
285  left = mmf->data_end - avio_tell(s->pb);
286  size = FFMIN(left, MAX_SIZE);
287  if (avio_feof(s->pb) || size <= 0)
288  return AVERROR_EOF;
289 
290  ret = av_get_packet(s->pb, pkt, size);
291  if (ret < 0)
292  return ret;
293 
294  pkt->stream_index = 0;
295 
296  return ret;
297 }
298 
299 #if CONFIG_MMF_DEMUXER
301  .name = "mmf",
302  .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
303  .priv_data_size = sizeof(MMFContext),
308 };
309 #endif
310 
311 #if CONFIG_MMF_MUXER
313  .name = "mmf",
314  .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
315  .mime_type = "application/vnd.smaf",
316  .extensions = "mmf",
317  .priv_data_size = sizeof(MMFContext),
318  .audio_codec = AV_CODEC_ID_ADPCM_YAMAHA,
319  .video_codec = AV_CODEC_ID_NONE,
320  .write_header = mmf_write_header,
322  .write_trailer = mmf_write_trailer,
323 };
324 #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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
ffio_wfourcc
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:116
FF_COMPLIANCE_EXPERIMENTAL
#define FF_COMPLIANCE_EXPERIMENTAL
Allow nonstandardized experimental things.
Definition: avcodec.h:1305
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
MMFContext::stereo
int stereo
Definition: mmf.c:36
MMFContext::atrpos
int64_t atrpos
Definition: mmf.c:34
MMFContext::awapos
int64_t awapos
Definition: mmf.c:34
MAX_SIZE
#define MAX_SIZE
Definition: mmf.c:277
mmf_probe
static int mmf_probe(const AVProbeData *p)
Definition: mmf.c:182
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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:697
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:505
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:482
val
static double val(void *priv, double ch)
Definition: aeval.c:77
MMFContext
Definition: mmf.c:33
ff_start_tag
int64_t ff_start_tag(AVIOContext *pb, const char *tag)
Definition: riffenc.c:32
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:790
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:656
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
MMFContext::data_end
int64_t data_end
Definition: mmf.c:35
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:31
ff_mmf_muxer
const AVOutputFormat ff_mmf_muxer
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
mmf_rates
static const int mmf_rates[]
Definition: mmf.c:39
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:529
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AV_CODEC_ID_ADPCM_YAMAHA
@ AV_CODEC_ID_ADPCM_YAMAHA
Definition: codec_id.h:370
write_trailer
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:100
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
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:960
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:210
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
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:117
mmf_rate
static int mmf_rate(int code)
Definition: mmf.c:41
size
int size
Definition: twinvq_data.h:10344
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:232
avio_wb32
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:394
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
version
version
Definition: libkvazaar.c:313
rawenc.h
mmf_read_header
static int mmf_read_header(AVFormatContext *s)
Definition: mmf.c:195
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVOutputFormat
Definition: avformat.h:509
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
MMFContext::atsqpos
int64_t atsqpos
Definition: mmf.c:34
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
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
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:102
version.h
tag
uint32_t tag
Definition: movenc.c:1631
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:1348
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
pos
unsigned int pos
Definition: spdifenc.c:412
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:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
mmf_read_packet
static int mmf_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mmf.c:279
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
riff.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:90
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
write_packet
static int write_packet(AVFormatContext *s1, AVPacket *pkt)
Definition: v4l2enc.c:92
write_header
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:346
ff_mmf_demuxer
const AVInputFormat ff_mmf_demuxer
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:375