FFmpeg
cbs.h
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
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8  *
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10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVCODEC_CBS_H
20 #define AVCODEC_CBS_H
21 
22 #include <stddef.h>
23 #include <stdint.h>
24 
25 #include "libavutil/buffer.h"
26 
27 #include "codec_id.h"
28 #include "codec_par.h"
29 #include "defs.h"
30 #include "packet.h"
31 
32 
33 /*
34  * This defines a framework for converting between a coded bitstream
35  * and structures defining all individual syntax elements found in
36  * such a stream.
37  *
38  * Conversion in both directions is possible. Given a coded bitstream
39  * (any meaningful fragment), it can be parsed and decomposed into
40  * syntax elements stored in a set of codec-specific structures.
41  * Similarly, given a set of those same codec-specific structures the
42  * syntax elements can be serialised and combined to create a coded
43  * bitstream.
44  */
45 
46 struct AVCodecContext;
48 
49 /**
50  * The codec-specific type of a bitstream unit.
51  *
52  * AV1: obu_type
53  * H.264 / AVC: nal_unit_type
54  * H.265 / HEVC: nal_unit_type
55  * JPEG: marker value (without 0xff prefix)
56  * MPEG-2: start code value (without prefix)
57  * VP9: unused, set to zero (every unit is a frame)
58  */
59 typedef uint32_t CodedBitstreamUnitType;
60 
61 /**
62  * Coded bitstream unit structure.
63  *
64  * A bitstream unit the smallest element of a bitstream which
65  * is meaningful on its own. For example, an H.264 NAL unit.
66  *
67  * See the codec-specific header for the meaning of this for any
68  * particular codec.
69  */
70 typedef struct CodedBitstreamUnit {
71  /**
72  * Codec-specific type of this unit.
73  */
75 
76  /**
77  * Pointer to the directly-parsable bitstream form of this unit.
78  *
79  * May be NULL if the unit currently only exists in decomposed form.
80  */
81  uint8_t *data;
82  /**
83  * The number of bytes in the bitstream (including any padding bits
84  * in the final byte).
85  */
86  size_t data_size;
87  /**
88  * The number of bits which should be ignored in the final byte.
89  *
90  * This supports non-byte-aligned bitstreams.
91  */
93  /**
94  * A reference to the buffer containing data.
95  *
96  * Must be set if data is not NULL.
97  */
99 
100  /**
101  * Pointer to the decomposed form of this unit.
102  *
103  * The type of this structure depends on both the codec and the
104  * type of this unit. May be NULL if the unit only exists in
105  * bitstream form.
106  */
107  void *content;
108  /**
109  * If content is reference counted, a RefStruct reference backing content.
110  * NULL if content is not reference counted.
111  */
112  void *content_ref;
114 
115 /**
116  * Coded bitstream fragment structure, combining one or more units.
117  *
118  * This is any sequence of units. It need not form some greater whole,
119  * though in many cases it will. For example, an H.264 access unit,
120  * which is composed of a sequence of H.264 NAL units.
121  */
122 typedef struct CodedBitstreamFragment {
123  /**
124  * Pointer to the bitstream form of this fragment.
125  *
126  * May be NULL if the fragment only exists as component units.
127  */
128  uint8_t *data;
129  /**
130  * The number of bytes in the bitstream.
131  *
132  * The number of bytes in the bitstream (including any padding bits
133  * in the final byte).
134  */
135  size_t data_size;
136  /**
137  * The number of bits which should be ignored in the final byte.
138  */
140  /**
141  * A reference to the buffer containing data.
142  *
143  * Must be set if data is not NULL.
144  */
146 
147  /**
148  * Number of units in this fragment.
149  *
150  * This may be zero if the fragment only exists in bitstream form
151  * and has not been decomposed.
152  */
153  int nb_units;
154 
155  /**
156  * Number of allocated units.
157  *
158  * Must always be >= nb_units; designed for internal use by cbs.
159  */
161 
162  /**
163  * Pointer to an array of units of length nb_units_allocated.
164  * Only the first nb_units are valid.
165  *
166  * Must be NULL if nb_units_allocated is zero.
167  */
170 
171 
172 struct CodedBitstreamContext;
173 struct GetBitContext;
174 struct PutBitContext;
175 
176 /**
177  * Callback type for read tracing.
178  *
179  * @param ctx User-set trace context.
180  * @param gbc A GetBitContext set at the start of the syntax
181  * element. This is a copy, the callee does not
182  * need to preserve it.
183  * @param length Length in bits of the syntax element.
184  * @param name String name of the syntax elements.
185  * @param subscripts If the syntax element is an array, a pointer to
186  * an array of subscripts into the array.
187  * @param value Parsed value of the syntax element.
188  */
189 typedef void (*CBSTraceReadCallback)(void *trace_context,
190  struct GetBitContext *gbc,
191  int start_position,
192  const char *name,
193  const int *subscripts,
194  int64_t value);
195 
196 /**
197  * Callback type for write tracing.
198  *
199  * @param ctx User-set trace context.
200  * @param pbc A PutBitContext set at the end of the syntax
201  * element. The user must not modify this, but may
202  * inspect it to determine state.
203  * @param length Length in bits of the syntax element.
204  * @param name String name of the syntax elements.
205  * @param subscripts If the syntax element is an array, a pointer to
206  * an array of subscripts into the array.
207  * @param value Written value of the syntax element.
208  */
209 typedef void (*CBSTraceWriteCallback)(void *trace_context,
210  struct PutBitContext *pbc,
211  int start_position,
212  const char *name,
213  const int *subscripts,
214  int64_t value);
215 
216 /**
217  * Context structure for coded bitstream operations.
218  */
219 typedef struct CodedBitstreamContext {
220  /**
221  * Logging context to be passed to all av_log() calls associated
222  * with this context.
223  */
224  void *log_ctx;
225 
226  /**
227  * Internal codec-specific hooks.
228  */
229  const struct CodedBitstreamType *codec;
230 
231  /**
232  * Internal codec-specific data.
233  *
234  * This contains any information needed when reading/writing
235  * bitsteams which will not necessarily be present in a fragment.
236  * For example, for H.264 it contains all currently visible
237  * parameter sets - they are required to determine the bitstream
238  * syntax but need not be present in every access unit.
239  */
240  void *priv_data;
241 
242  /**
243  * Array of unit types which should be decomposed when reading.
244  *
245  * Types not in this list will be available in bitstream form only.
246  * If NULL, all supported types will be decomposed.
247  */
249  /**
250  * Length of the decompose_unit_types array.
251  */
253 
254  /**
255  * Enable trace output during read/write operations.
256  */
258  /**
259  * Log level to use for default trace output.
260  *
261  * From AV_LOG_*; defaults to AV_LOG_TRACE.
262  */
264  /**
265  * User context pointer to pass to trace callbacks.
266  */
268  /**
269  * Callback for read tracing.
270  *
271  * If tracing is enabled then this is called once for each syntax
272  * element parsed.
273  */
275  /**
276  * Callback for write tracing.
277  *
278  * If tracing is enabled then this is called once for each syntax
279  * element written.
280  */
282 
283  /**
284  * Write buffer. Used as intermediate buffer when writing units.
285  * For internal use of cbs only.
286  */
287  uint8_t *write_buffer;
290 
291 
292 /**
293  * Table of all supported codec IDs.
294  *
295  * Terminated by AV_CODEC_ID_NONE.
296  */
297 extern const enum AVCodecID ff_cbs_all_codec_ids[];
298 
299 
300 /**
301  * Create and initialise a new context for the given codec.
302  */
304  enum AVCodecID codec_id, void *log_ctx);
305 
306 /**
307  * Reset all internal state in a context.
308  */
310 
311 /**
312  * Close a context and free all internal state.
313  */
315 
316 
317 /**
318  * Read the extradata bitstream found in codec parameters into a
319  * fragment, then split into units and decompose.
320  *
321  * This also updates the internal state, so will need to be called for
322  * codecs with extradata to read parameter sets necessary for further
323  * parsing even if the fragment itself is not desired.
324  *
325  * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
326  * before use.
327  */
330  const AVCodecParameters *par);
331 
332 /**
333  * Read the extradata bitstream found in a codec context into a
334  * fragment, then split into units and decompose.
335  *
336  * This acts identical to ff_cbs_read_extradata() for the case where
337  * you already have a codec context.
338  */
341  const struct AVCodecContext *avctx);
342 
345  const AVPacket *pkt);
346 
347 /**
348  * Read the data bitstream from a packet into a fragment, then
349  * split into units and decompose.
350  *
351  * This also updates the internal state of the coded bitstream context
352  * with any persistent data from the fragment which may be required to
353  * read following fragments (e.g. parameter sets).
354  *
355  * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
356  * before use.
357  */
360  const AVPacket *pkt);
361 
362 /**
363  * Read a bitstream from a memory region into a fragment, then
364  * split into units and decompose.
365  *
366  * This also updates the internal state of the coded bitstream context
367  * with any persistent data from the fragment which may be required to
368  * read following fragments (e.g. parameter sets).
369  *
370  * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
371  * before use.
372  */
375  const uint8_t *data, size_t size);
376 
377 
378 /**
379  * Write the content of the fragment to its own internal buffer.
380  *
381  * Writes the content of all units and then assembles them into a new
382  * data buffer. When modifying the content of decomposed units, this
383  * can be used to regenerate the bitstream form of units or the whole
384  * fragment so that it can be extracted for other use.
385  *
386  * This also updates the internal state of the coded bitstream context
387  * with any persistent data from the fragment which may be required to
388  * write following fragments (e.g. parameter sets).
389  */
391  CodedBitstreamFragment *frag);
392 
393 /**
394  * Write the bitstream of a fragment to the extradata in codec parameters.
395  *
396  * Modifies context and fragment as ff_cbs_write_fragment_data does and
397  * replaces any existing extradata in the structure.
398  */
400  AVCodecParameters *par,
401  CodedBitstreamFragment *frag);
402 
403 /**
404  * Write the bitstream of a fragment to a packet.
405  *
406  * Modifies context and fragment as ff_cbs_write_fragment_data does.
407  *
408  * On success, the packet's buf is unreferenced and its buf, data and
409  * size fields are set to the corresponding values from the newly updated
410  * fragment; other fields are not touched. On failure, the packet is not
411  * touched at all.
412  */
414  AVPacket *pkt,
415  CodedBitstreamFragment *frag);
416 
417 
418 /**
419  * Free the units contained in a fragment as well as the fragment's
420  * own data buffer, but not the units array itself.
421  */
423 
424 /**
425  * Free the units array of a fragment in addition to what
426  * ff_cbs_fragment_reset does.
427  */
429 
430 /**
431  * Allocate a new internal content buffer matching the type of the unit.
432  *
433  * The content will be zeroed.
434  */
436  CodedBitstreamUnit *unit);
437 
438 /**
439  * Insert a new unit into a fragment with the given content.
440  *
441  * If content_ref is supplied, it has to be a RefStruct reference
442  * backing content; the user keeps ownership of the supplied reference.
443  * The content structure continues to be owned by the caller if
444  * content_ref is not supplied.
445  */
447  int position,
449  void *content,
450  void *content_ref);
451 
452 /**
453  * Add a new unit to a fragment with the given data bitstream.
454  *
455  * If data_buf is not supplied then data must have been allocated with
456  * av_malloc() and will on success become owned by the unit after this
457  * call or freed on error.
458  */
461  uint8_t *data, size_t data_size,
462  AVBufferRef *data_buf);
463 
464 /**
465  * Delete a unit from a fragment and free all memory it uses.
466  *
467  * Requires position to be >= 0 and < frag->nb_units.
468  */
470  int position);
471 
472 
473 /**
474  * Make the content of a unit refcounted.
475  *
476  * If the unit is not refcounted, this will do a deep copy of the unit
477  * content to new refcounted buffers.
478  *
479  * It is not valid to call this function on a unit which does not have
480  * decomposed content.
481  */
483  CodedBitstreamUnit *unit);
484 
485 /**
486  * Make the content of a unit writable so that internal fields can be
487  * modified.
488  *
489  * If it is known that there are no other references to the content of
490  * the unit, does nothing and returns success. Otherwise (including the
491  * case where the unit content is not refcounted), it does a full clone
492  * of the content (including any internal buffers) to make a new copy,
493  * and replaces the existing references inside the unit with that.
494  *
495  * It is not valid to call this function on a unit which does not have
496  * decomposed content.
497  */
499  CodedBitstreamUnit *unit);
500 
503 
504  /**
505  * keep non-vcl units even if the picture has been dropped.
506  */
508 };
509 
510 /**
511  * Discard units accroding to 'skip'.
512  */
515  enum AVDiscard skip,
516  int flags);
517 
518 
519 /**
520  * Helper function for read tracing which formats the syntax element
521  * and logs the result.
522  *
523  * Trace context should be set to the CodedBitstreamContext.
524  */
525 void ff_cbs_trace_read_log(void *trace_context,
526  struct GetBitContext *gbc, int length,
527  const char *str, const int *subscripts,
528  int64_t value);
529 
530 /**
531  * Helper function for write tracing which formats the syntax element
532  * and logs the result.
533  *
534  * Trace context should be set to the CodedBitstreamContext.
535  */
536 void ff_cbs_trace_write_log(void *trace_context,
537  struct PutBitContext *pbc, int length,
538  const char *str, const int *subscripts,
539  int64_t value);
540 
541 #endif /* AVCODEC_CBS_H */
CodedBitstreamUnit::content_ref
void * content_ref
If content is reference counted, a RefStruct reference backing content.
Definition: cbs.h:112
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
CodedBitstreamContext::priv_data
void * priv_data
Internal codec-specific data.
Definition: cbs.h:240
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
ff_cbs_make_unit_refcounted
int ff_cbs_make_unit_refcounted(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit)
Make the content of a unit refcounted.
Definition: cbs.c:1034
CodedBitstreamContext::codec
const struct CodedBitstreamType * codec
Internal codec-specific hooks.
Definition: cbs.h:229
CodedBitstreamUnit::content
void * content
Pointer to the decomposed form of this unit.
Definition: cbs.h:107
ff_cbs_init
int ff_cbs_init(CodedBitstreamContext **ctx, enum AVCodecID codec_id, void *log_ctx)
Create and initialise a new context for the given codec.
Definition: cbs.c:89
CodedBitstreamContext::write_buffer
uint8_t * write_buffer
Write buffer.
Definition: cbs.h:287
DISCARD_FLAG_NONE
@ DISCARD_FLAG_NONE
Definition: cbs.h:502
CodedBitstreamContext
Context structure for coded bitstream operations.
Definition: cbs.h:219
CBSTraceWriteCallback
void(* CBSTraceWriteCallback)(void *trace_context, struct PutBitContext *pbc, int start_position, const char *name, const int *subscripts, int64_t value)
Callback type for write tracing.
Definition: cbs.h:209
ff_cbs_read_packet_side_data
int ff_cbs_read_packet_side_data(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVPacket *pkt)
Definition: cbs.c:311
data
const char data[16]
Definition: mxf.c:148
CodedBitstreamUnit::type
CodedBitstreamUnitType type
Codec-specific type of this unit.
Definition: cbs.h:74
ff_cbs_read_packet
int ff_cbs_read_packet(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVPacket *pkt)
Read the data bitstream from a packet into a fragment, then split into units and decompose.
Definition: cbs.c:303
CodedBitstreamUnit
Coded bitstream unit structure.
Definition: cbs.h:70
ff_cbs_write_packet
int ff_cbs_write_packet(CodedBitstreamContext *ctx, AVPacket *pkt, CodedBitstreamFragment *frag)
Write the bitstream of a fragment to a packet.
Definition: cbs.c:473
CodedBitstreamContext::log_ctx
void * log_ctx
Logging context to be passed to all av_log() calls associated with this context.
Definition: cbs.h:224
DISCARD_FLAG_KEEP_NON_VCL
@ DISCARD_FLAG_KEEP_NON_VCL
keep non-vcl units even if the picture has been dropped.
Definition: cbs.h:507
ff_cbs_discard_units
void ff_cbs_discard_units(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, enum AVDiscard skip, int flags)
Discard units accroding to 'skip'.
Definition: cbs.c:1060
ff_cbs_fragment_free
void ff_cbs_fragment_free(CodedBitstreamFragment *frag)
Free the units array of a fragment in addition to what ff_cbs_fragment_reset does.
Definition: cbs.c:185
ff_cbs_trace_read_log
void ff_cbs_trace_read_log(void *trace_context, struct GetBitContext *gbc, int length, const char *str, const int *subscripts, int64_t value)
Helper function for read tracing which formats the syntax element and logs the result.
Definition: cbs.c:507
GetBitContext
Definition: get_bits.h:108
CodedBitstreamContext::trace_read_callback
CBSTraceReadCallback trace_read_callback
Callback for read tracing.
Definition: cbs.h:274
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
CodedBitstreamUnit::data
uint8_t * data
Pointer to the directly-parsable bitstream form of this unit.
Definition: cbs.h:81
CodedBitstreamContext::trace_level
int trace_level
Log level to use for default trace output.
Definition: cbs.h:263
CodedBitstreamFragment::units
CodedBitstreamUnit * units
Pointer to an array of units of length nb_units_allocated.
Definition: cbs.h:168
pkt
AVPacket * pkt
Definition: movenc.c:59
codec_id.h
CodedBitstreamFragment
Coded bitstream fragment structure, combining one or more units.
Definition: cbs.h:122
CodedBitstreamFragment::data_size
size_t data_size
The number of bytes in the bitstream.
Definition: cbs.h:135
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ff_cbs_read
int ff_cbs_read(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const uint8_t *data, size_t size)
Read a bitstream from a memory region into a fragment, then split into units and decompose.
Definition: cbs.c:324
ff_cbs_insert_unit_content
int ff_cbs_insert_unit_content(CodedBitstreamFragment *frag, int position, CodedBitstreamUnitType type, void *content, void *content_ref)
Insert a new unit into a fragment with the given content.
Definition: cbs.c:782
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:389
CodedBitstreamFragment::data_bit_padding
size_t data_bit_padding
The number of bits which should be ignored in the final byte.
Definition: cbs.h:139
PutBitContext
Definition: put_bits.h:50
ff_cbs_fragment_reset
void ff_cbs_fragment_reset(CodedBitstreamFragment *frag)
Free the units contained in a fragment as well as the fragment's own data buffer, but not the units a...
Definition: cbs.c:171
ff_cbs_trace_write_log
void ff_cbs_trace_write_log(void *trace_context, struct PutBitContext *pbc, int length, const char *str, const int *subscripts, int64_t value)
Helper function for write tracing which formats the syntax element and logs the result.
Definition: cbs.c:565
CodedBitstreamContext::trace_context
void * trace_context
User context pointer to pass to trace callbacks.
Definition: cbs.h:267
CodedBitstreamUnit::data_size
size_t data_size
The number of bytes in the bitstream (including any padding bits in the final byte).
Definition: cbs.h:86
ff_cbs_append_unit_data
int ff_cbs_append_unit_data(CodedBitstreamFragment *frag, CodedBitstreamUnitType type, uint8_t *data, size_t data_size, AVBufferRef *data_buf)
Add a new unit to a fragment with the given data bitstream.
Definition: cbs.c:849
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
CbsDiscardFlags
CbsDiscardFlags
Definition: cbs.h:501
CodedBitstreamContext::write_buffer_size
size_t write_buffer_size
Definition: cbs.h:288
size
int size
Definition: twinvq_data.h:10344
CodedBitstreamFragment::data
uint8_t * data
Pointer to the bitstream form of this fragment.
Definition: cbs.h:128
CodedBitstreamUnit::data_bit_padding
size_t data_bit_padding
The number of bits which should be ignored in the final byte.
Definition: cbs.h:92
ff_cbs_write_extradata
int ff_cbs_write_extradata(CodedBitstreamContext *ctx, AVCodecParameters *par, CodedBitstreamFragment *frag)
Write the bitstream of a fragment to the extradata in codec parameters.
Definition: cbs.c:444
CodedBitstreamContext::trace_write_callback
CBSTraceWriteCallback trace_write_callback
Callback for write tracing.
Definition: cbs.h:281
ff_cbs_read_extradata
int ff_cbs_read_extradata(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVCodecParameters *par)
Read the extradata bitstream found in codec parameters into a fragment, then split into units and dec...
Definition: cbs.c:285
CBSTraceReadCallback
void(* CBSTraceReadCallback)(void *trace_context, struct GetBitContext *gbc, int start_position, const char *name, const int *subscripts, int64_t value)
Callback type for read tracing.
Definition: cbs.h:189
buffer.h
CodedBitstreamType
Definition: cbs_internal.h:102
ff_cbs_flush
void ff_cbs_flush(CodedBitstreamContext *ctx)
Reset all internal state in a context.
Definition: cbs.c:135
ff_cbs_delete_unit
void ff_cbs_delete_unit(CodedBitstreamFragment *frag, int position)
Delete a unit from a fragment and free all memory it uses.
Definition: cbs.c:859
ff_cbs_close
void ff_cbs_close(CodedBitstreamContext **ctx)
Close a context and free all internal state.
Definition: cbs.c:141
CodedBitstreamUnit::data_ref
AVBufferRef * data_ref
A reference to the buffer containing data.
Definition: cbs.h:98
packet.h
ff_cbs_all_codec_ids
enum AVCodecID ff_cbs_all_codec_ids[]
Table of all supported codec IDs.
Definition: cbs.c:61
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
CodedBitstreamFragment::nb_units_allocated
int nb_units_allocated
Number of allocated units.
Definition: cbs.h:160
AVCodecContext
main external API structure.
Definition: avcodec.h:445
CodedBitstreamUnitType
uint32_t CodedBitstreamUnitType
The codec-specific type of a bitstream unit.
Definition: cbs.h:47
defs.h
CodedBitstreamContext::trace_enable
int trace_enable
Enable trace output during read/write operations.
Definition: cbs.h:257
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
ff_cbs_make_unit_writable
int ff_cbs_make_unit_writable(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit)
Make the content of a unit writable so that internal fields can be modified.
Definition: cbs.c:1043
codec_par.h
AVPacket
This structure stores compressed data.
Definition: packet.h:499
CodedBitstreamContext::nb_decompose_unit_types
int nb_decompose_unit_types
Length of the decompose_unit_types array.
Definition: cbs.h:252
CodedBitstreamContext::decompose_unit_types
const CodedBitstreamUnitType * decompose_unit_types
Array of unit types which should be decomposed when reading.
Definition: cbs.h:248
ff_cbs_alloc_unit_content
int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit)
Allocate a new internal content buffer matching the type of the unit.
Definition: cbs.c:922
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
CodedBitstreamFragment::data_ref
AVBufferRef * data_ref
A reference to the buffer containing data.
Definition: cbs.h:145
AVDiscard
AVDiscard
Definition: defs.h:210
ff_cbs_write_fragment_data
int ff_cbs_write_fragment_data(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
Write the content of the fragment to its own internal buffer.
Definition: cbs.c:408
ff_cbs_read_extradata_from_codec
int ff_cbs_read_extradata_from_codec(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const struct AVCodecContext *avctx)
Read the extradata bitstream found in a codec context into a fragment, then split into units and deco...
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
CodedBitstreamFragment::nb_units
int nb_units
Number of units in this fragment.
Definition: cbs.h:153