FFmpeg 5.1.6
avfilter.h
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1/*
2 * filter layer
3 * Copyright (c) 2007 Bobby Bingham
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#ifndef AVFILTER_AVFILTER_H
23#define AVFILTER_AVFILTER_H
24
25/**
26 * @file
27 * @ingroup lavfi
28 * Main libavfilter public API header
29 */
30
31/**
32 * @defgroup lavfi libavfilter
33 * Graph-based frame editing library.
34 *
35 * @{
36 */
37
38#include <stddef.h>
39
41#include "libavutil/avutil.h"
42#include "libavutil/buffer.h"
43#include "libavutil/dict.h"
44#include "libavutil/frame.h"
45#include "libavutil/log.h"
46#include "libavutil/samplefmt.h"
47#include "libavutil/pixfmt.h"
48#include "libavutil/rational.h"
49
51#ifndef HAVE_AV_CONFIG_H
52/* When included as part of the ffmpeg build, only include the major version
53 * to avoid unnecessary rebuilds. When included externally, keep including
54 * the full version information. */
55#include "libavfilter/version.h"
56#endif
57
58/**
59 * Return the LIBAVFILTER_VERSION_INT constant.
60 */
61unsigned avfilter_version(void);
62
63/**
64 * Return the libavfilter build-time configuration.
65 */
66const char *avfilter_configuration(void);
67
68/**
69 * Return the libavfilter license.
70 */
71const char *avfilter_license(void);
72
73typedef struct AVFilterContext AVFilterContext;
74typedef struct AVFilterLink AVFilterLink;
75typedef struct AVFilterPad AVFilterPad;
78
79#if FF_API_PAD_COUNT
80/**
81 * Get the number of elements in an AVFilter's inputs or outputs array.
82 *
83 * @deprecated Use avfilter_filter_pad_count() instead.
84 */
87#endif
88
89/**
90 * Get the name of an AVFilterPad.
91 *
92 * @param pads an array of AVFilterPads
93 * @param pad_idx index of the pad in the array; it is the caller's
94 * responsibility to ensure the index is valid
95 *
96 * @return name of the pad_idx'th pad in pads
97 */
98const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
99
100/**
101 * Get the type of an AVFilterPad.
102 *
103 * @param pads an array of AVFilterPads
104 * @param pad_idx index of the pad in the array; it is the caller's
105 * responsibility to ensure the index is valid
106 *
107 * @return type of the pad_idx'th pad in pads
108 */
109enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
110
111/**
112 * The number of the filter inputs is not determined just by AVFilter.inputs.
113 * The filter might add additional inputs during initialization depending on the
114 * options supplied to it.
115 */
116#define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
117/**
118 * The number of the filter outputs is not determined just by AVFilter.outputs.
119 * The filter might add additional outputs during initialization depending on
120 * the options supplied to it.
121 */
122#define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
123/**
124 * The filter supports multithreading by splitting frames into multiple parts
125 * and processing them concurrently.
126 */
127#define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
128/**
129 * The filter is a "metadata" filter - it does not modify the frame data in any
130 * way. It may only affect the metadata (i.e. those fields copied by
131 * av_frame_copy_props()).
132 *
133 * More precisely, this means:
134 * - video: the data of any frame output by the filter must be exactly equal to
135 * some frame that is received on one of its inputs. Furthermore, all frames
136 * produced on a given output must correspond to frames received on the same
137 * input and their order must be unchanged. Note that the filter may still
138 * drop or duplicate the frames.
139 * - audio: the data produced by the filter on any of its outputs (viewed e.g.
140 * as an array of interleaved samples) must be exactly equal to the data
141 * received by the filter on one of its inputs.
142 */
143#define AVFILTER_FLAG_METADATA_ONLY (1 << 3)
144/**
145 * Some filters support a generic "enable" expression option that can be used
146 * to enable or disable a filter in the timeline. Filters supporting this
147 * option have this flag set. When the enable expression is false, the default
148 * no-op filter_frame() function is called in place of the filter_frame()
149 * callback defined on each input pad, thus the frame is passed unchanged to
150 * the next filters.
151 */
152#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
153/**
154 * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
155 * have its filter_frame() callback(s) called as usual even when the enable
156 * expression is false. The filter will disable filtering within the
157 * filter_frame() callback(s) itself, for example executing code depending on
158 * the AVFilterContext->is_disabled value.
159 */
160#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
161/**
162 * Handy mask to test whether the filter supports or no the timeline feature
163 * (internally or generically).
164 */
165#define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
166
167/**
168 * Filter definition. This defines the pads a filter contains, and all the
169 * callback functions used to interact with the filter.
170 */
171typedef struct AVFilter {
172 /**
173 * Filter name. Must be non-NULL and unique among filters.
174 */
175 const char *name;
176
177 /**
178 * A description of the filter. May be NULL.
179 *
180 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
181 */
182 const char *description;
183
184 /**
185 * List of static inputs.
186 *
187 * NULL if there are no (static) inputs. Instances of filters with
188 * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
189 * this list.
190 */
192
193 /**
194 * List of static outputs.
195 *
196 * NULL if there are no (static) outputs. Instances of filters with
197 * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
198 * this list.
199 */
201
202 /**
203 * A class for the private data, used to declare filter private AVOptions.
204 * This field is NULL for filters that do not declare any options.
205 *
206 * If this field is non-NULL, the first member of the filter private data
207 * must be a pointer to AVClass, which will be set by libavfilter generic
208 * code to this class.
209 */
211
212 /**
213 * A combination of AVFILTER_FLAG_*
214 */
215 int flags;
216
217 /*****************************************************************
218 * All fields below this line are not part of the public API. They
219 * may not be used outside of libavfilter and can be changed and
220 * removed at will.
221 * New public fields should be added right above.
222 *****************************************************************
223 */
224
225 /**
226 * The number of entries in the list of inputs.
227 */
228 uint8_t nb_inputs;
229
230 /**
231 * The number of entries in the list of outputs.
232 */
233 uint8_t nb_outputs;
234
235 /**
236 * This field determines the state of the formats union.
237 * It is an enum FilterFormatsState value.
238 */
240
241 /**
242 * Filter pre-initialization function
243 *
244 * This callback will be called immediately after the filter context is
245 * allocated, to allow allocating and initing sub-objects.
246 *
247 * If this callback is not NULL, the uninit callback will be called on
248 * allocation failure.
249 *
250 * @return 0 on success,
251 * AVERROR code on failure (but the code will be
252 * dropped and treated as ENOMEM by the calling code)
253 */
255
256 /**
257 * Filter initialization function.
258 *
259 * This callback will be called only once during the filter lifetime, after
260 * all the options have been set, but before links between filters are
261 * established and format negotiation is done.
262 *
263 * Basic filter initialization should be done here. Filters with dynamic
264 * inputs and/or outputs should create those inputs/outputs here based on
265 * provided options. No more changes to this filter's inputs/outputs can be
266 * done after this callback.
267 *
268 * This callback must not assume that the filter links exist or frame
269 * parameters are known.
270 *
271 * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
272 * initialization fails, so this callback does not have to clean up on
273 * failure.
274 *
275 * @return 0 on success, a negative AVERROR on failure
276 */
277 int (*init)(AVFilterContext *ctx);
278
279 /**
280 * Should be set instead of @ref AVFilter.init "init" by the filters that
281 * want to pass a dictionary of AVOptions to nested contexts that are
282 * allocated during init.
283 *
284 * On return, the options dict should be freed and replaced with one that
285 * contains all the options which could not be processed by this filter (or
286 * with NULL if all the options were processed).
287 *
288 * Otherwise the semantics is the same as for @ref AVFilter.init "init".
289 */
290 int (*init_dict)(AVFilterContext *ctx, AVDictionary **options);
291
292 /**
293 * Filter uninitialization function.
294 *
295 * Called only once right before the filter is freed. Should deallocate any
296 * memory held by the filter, release any buffer references, etc. It does
297 * not need to deallocate the AVFilterContext.priv memory itself.
298 *
299 * This callback may be called even if @ref AVFilter.init "init" was not
300 * called or failed, so it must be prepared to handle such a situation.
301 */
302 void (*uninit)(AVFilterContext *ctx);
303
304 /**
305 * The state of the following union is determined by formats_state.
306 * See the documentation of enum FilterFormatsState in internal.h.
307 */
308 union {
309 /**
310 * Query formats supported by the filter on its inputs and outputs.
311 *
312 * This callback is called after the filter is initialized (so the inputs
313 * and outputs are fixed), shortly before the format negotiation. This
314 * callback may be called more than once.
315 *
316 * This callback must set AVFilterLink.outcfg.formats on every input link
317 * and AVFilterLink.incfg.formats on every output link to a list of
318 * pixel/sample formats that the filter supports on that link. For audio
319 * links, this filter must also set @ref AVFilterLink.incfg.samplerates
320 * "in_samplerates" / @ref AVFilterLink.outcfg.samplerates "out_samplerates"
321 * and @ref AVFilterLink.incfg.channel_layouts "in_channel_layouts" /
322 * @ref AVFilterLink.outcfg.channel_layouts "out_channel_layouts" analogously.
323 *
324 * This callback must never be NULL if the union is in this state.
325 *
326 * @return zero on success, a negative value corresponding to an
327 * AVERROR code otherwise
328 */
330 /**
331 * A pointer to an array of admissible pixel formats delimited
332 * by AV_PIX_FMT_NONE. The generic code will use this list
333 * to indicate that this filter supports each of these pixel formats,
334 * provided that all inputs and outputs use the same pixel format.
335 *
336 * This list must never be NULL if the union is in this state.
337 * The type of all inputs and outputs of filters using this must
338 * be AVMEDIA_TYPE_VIDEO.
339 */
341 /**
342 * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
343 * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
344 * inputs and outputs.
345 *
346 * In addition to that the generic code will mark all inputs
347 * and all outputs as supporting all sample rates and every
348 * channel count and channel layout, as long as all inputs
349 * and outputs use the same sample rate and channel count/layout.
350 */
352 /**
353 * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
354 */
356 /**
357 * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
358 */
361
362 int priv_size; ///< size of private data to allocate for the filter
363
364 int flags_internal; ///< Additional flags for avfilter internal use only.
365
366 /**
367 * Make the filter instance process a command.
368 *
369 * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
370 * @param arg the argument for the command
371 * @param res a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported.
372 * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
373 * time consuming then a filter should treat it like an unsupported command
374 *
375 * @returns >=0 on success otherwise an error code.
376 * AVERROR(ENOSYS) on unsupported commands
377 */
378 int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
379
380 /**
381 * Filter activation function.
382 *
383 * Called when any processing is needed from the filter, instead of any
384 * filter_frame and request_frame on pads.
385 *
386 * The function must examine inlinks and outlinks and perform a single
387 * step of processing. If there is nothing to do, the function must do
388 * nothing and not return an error. If more steps are or may be
389 * possible, it must use ff_filter_set_ready() to schedule another
390 * activation.
391 */
393} AVFilter;
394
395/**
396 * Get the number of elements in an AVFilter's inputs or outputs array.
397 */
398unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
399
400/**
401 * Process multiple parts of the frame concurrently.
402 */
403#define AVFILTER_THREAD_SLICE (1 << 0)
404
406
407/** An instance of a filter */
409 const AVClass *av_class; ///< needed for av_log() and filters common options
410
411 const AVFilter *filter; ///< the AVFilter of which this is an instance
412
413 char *name; ///< name of this filter instance
414
415 AVFilterPad *input_pads; ///< array of input pads
416 AVFilterLink **inputs; ///< array of pointers to input links
417 unsigned nb_inputs; ///< number of input pads
418
419 AVFilterPad *output_pads; ///< array of output pads
420 AVFilterLink **outputs; ///< array of pointers to output links
421 unsigned nb_outputs; ///< number of output pads
422
423 void *priv; ///< private data for use by the filter
424
425 struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
426
427 /**
428 * Type of multithreading being allowed/used. A combination of
429 * AVFILTER_THREAD_* flags.
430 *
431 * May be set by the caller before initializing the filter to forbid some
432 * or all kinds of multithreading for this filter. The default is allowing
433 * everything.
434 *
435 * When the filter is initialized, this field is combined using bit AND with
436 * AVFilterGraph.thread_type to get the final mask used for determining
437 * allowed threading types. I.e. a threading type needs to be set in both
438 * to be allowed.
439 *
440 * After the filter is initialized, libavfilter sets this field to the
441 * threading type that is actually used (0 for no multithreading).
442 */
444
445 /**
446 * An opaque struct for libavfilter internal use.
447 */
449
450 struct AVFilterCommand *command_queue;
451
452 char *enable_str; ///< enable expression string
453 void *enable; ///< parsed expression (AVExpr*)
454 double *var_values; ///< variable values for the enable expression
455 int is_disabled; ///< the enabled state from the last expression evaluation
456
457 /**
458 * For filters which will create hardware frames, sets the device the
459 * filter should create them in. All other filters will ignore this field:
460 * in particular, a filter which consumes or processes hardware frames will
461 * instead use the hw_frames_ctx field in AVFilterLink to carry the
462 * hardware context information.
463 */
465
466 /**
467 * Max number of threads allowed in this filter instance.
468 * If <= 0, its value is ignored.
469 * Overrides global number of threads set per filter graph.
470 */
472
473 /**
474 * Ready status of the filter.
475 * A non-0 value means that the filter needs activating;
476 * a higher value suggests a more urgent activation.
477 */
478 unsigned ready;
479
480 /**
481 * Sets the number of extra hardware frames which the filter will
482 * allocate on its output links for use in following filters or by
483 * the caller.
484 *
485 * Some hardware filters require all frames that they will use for
486 * output to be defined in advance before filtering starts. For such
487 * filters, any hardware frame pools used for output must therefore be
488 * of fixed size. The extra frames set here are on top of any number
489 * that the filter needs internally in order to operate normally.
490 *
491 * This field must be set before the graph containing this filter is
492 * configured.
493 */
495};
496
497/**
498 * Lists of formats / etc. supported by an end of a link.
499 *
500 * This structure is directly part of AVFilterLink, in two copies:
501 * one for the source filter, one for the destination filter.
502
503 * These lists are used for negotiating the format to actually be used,
504 * which will be loaded into the format and channel_layout members of
505 * AVFilterLink, when chosen.
506 */
507typedef struct AVFilterFormatsConfig {
508
509 /**
510 * List of supported formats (pixel or sample).
511 */
513
514 /**
515 * Lists of supported sample rates, only for audio.
516 */
518
519 /**
520 * Lists of supported channel layouts, only for audio.
521 */
523
525
526/**
527 * A link between two filters. This contains pointers to the source and
528 * destination filters between which this link exists, and the indexes of
529 * the pads involved. In addition, this link also contains the parameters
530 * which have been negotiated and agreed upon between the filter, such as
531 * image dimensions, format, etc.
532 *
533 * Applications must not normally access the link structure directly.
534 * Use the buffersrc and buffersink API instead.
535 * In the future, access to the header may be reserved for filters
536 * implementation.
537 */
539 AVFilterContext *src; ///< source filter
540 AVFilterPad *srcpad; ///< output pad on the source filter
541
542 AVFilterContext *dst; ///< dest filter
543 AVFilterPad *dstpad; ///< input pad on the dest filter
544
545 enum AVMediaType type; ///< filter media type
546
547 /* These parameters apply only to video */
548 int w; ///< agreed upon image width
549 int h; ///< agreed upon image height
550 AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
551 /* These parameters apply only to audio */
552#if FF_API_OLD_CHANNEL_LAYOUT
553 /**
554 * channel layout of current buffer (see libavutil/channel_layout.h)
555 * @deprecated use ch_layout
556 */
558 uint64_t channel_layout;
559#endif
560 int sample_rate; ///< samples per second
561
562 int format; ///< agreed upon media format
563
564 /**
565 * Define the time base used by the PTS of the frames/samples
566 * which will pass through this link.
567 * During the configuration stage, each filter is supposed to
568 * change only the output timebase, while the timebase of the
569 * input link is assumed to be an unchangeable property.
570 */
572
573 AVChannelLayout ch_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
574
575 /*****************************************************************
576 * All fields below this line are not part of the public API. They
577 * may not be used outside of libavfilter and can be changed and
578 * removed at will.
579 * New public fields should be added right above.
580 *****************************************************************
581 */
582
583 /**
584 * Lists of supported formats / etc. supported by the input filter.
585 */
587
588 /**
589 * Lists of supported formats / etc. supported by the output filter.
590 */
592
593 /** stage of the initialization of the link properties (dimensions, etc) */
594 enum {
595 AVLINK_UNINIT = 0, ///< not started
596 AVLINK_STARTINIT, ///< started, but incomplete
597 AVLINK_INIT ///< complete
599
600 /**
601 * Graph the filter belongs to.
602 */
604
605 /**
606 * Current timestamp of the link, as defined by the most recent
607 * frame(s), in link time_base units.
608 */
609 int64_t current_pts;
610
611 /**
612 * Current timestamp of the link, as defined by the most recent
613 * frame(s), in AV_TIME_BASE units.
614 */
616
617 /**
618 * Index in the age array.
619 */
621
622 /**
623 * Frame rate of the stream on the link, or 1/0 if unknown or variable;
624 * if left to 0/0, will be automatically copied from the first input
625 * of the source filter if it exists.
626 *
627 * Sources should set it to the best estimation of the real frame rate.
628 * If the source frame rate is unknown or variable, set this to 1/0.
629 * Filters should update it if necessary depending on their function.
630 * Sinks can use it to set a default output frame rate.
631 * It is similar to the r_frame_rate field in AVStream.
632 */
634
635 /**
636 * Minimum number of samples to filter at once. If filter_frame() is
637 * called with fewer samples, it will accumulate them in fifo.
638 * This field and the related ones must not be changed after filtering
639 * has started.
640 * If 0, all related fields are ignored.
641 */
643
644 /**
645 * Maximum number of samples to filter at once. If filter_frame() is
646 * called with more samples, it will split them.
647 */
649
650 /**
651 * Number of past frames sent through the link.
652 */
654
655 /**
656 * Number of past samples sent through the link.
657 */
659
660 /**
661 * A pointer to a FFFramePool struct.
662 */
664
665 /**
666 * True if a frame is currently wanted on the output of this filter.
667 * Set when ff_request_frame() is called by the output,
668 * cleared when a frame is filtered.
669 */
671
672 /**
673 * For hwaccel pixel formats, this should be a reference to the
674 * AVHWFramesContext describing the frames.
675 */
677
678#ifndef FF_INTERNAL_FIELDS
679
680 /**
681 * Internal structure members.
682 * The fields below this limit are internal for libavfilter's use
683 * and must in no way be accessed by applications.
684 */
685 char reserved[0xF000];
686
687#else /* FF_INTERNAL_FIELDS */
688
689 /**
690 * Queue of frames waiting to be filtered.
691 */
692 FFFrameQueue fifo;
693
694 /**
695 * If set, the source filter can not generate a frame as is.
696 * The goal is to avoid repeatedly calling the request_frame() method on
697 * the same link.
698 */
699 int frame_blocked_in;
700
701 /**
702 * Link input status.
703 * If not zero, all attempts of filter_frame will fail with the
704 * corresponding code.
705 */
706 int status_in;
707
708 /**
709 * Timestamp of the input status change.
710 */
711 int64_t status_in_pts;
712
713 /**
714 * Link output status.
715 * If not zero, all attempts of request_frame will fail with the
716 * corresponding code.
717 */
718 int status_out;
719
720#endif /* FF_INTERNAL_FIELDS */
721
722};
723
724/**
725 * Link two filters together.
726 *
727 * @param src the source filter
728 * @param srcpad index of the output pad on the source filter
729 * @param dst the destination filter
730 * @param dstpad index of the input pad on the destination filter
731 * @return zero on success
732 */
733int avfilter_link(AVFilterContext *src, unsigned srcpad,
734 AVFilterContext *dst, unsigned dstpad);
735
736/**
737 * Free the link in *link, and set its pointer to NULL.
738 */
740
741/**
742 * Negotiate the media format, dimensions, etc of all inputs to a filter.
743 *
744 * @param filter the filter to negotiate the properties for its inputs
745 * @return zero on successful negotiation
746 */
748
749#define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
750#define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
751
752/**
753 * Make the filter instance process a command.
754 * It is recommended to use avfilter_graph_send_command().
755 */
756int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
757
758/**
759 * Iterate over all registered filters.
760 *
761 * @param opaque a pointer where libavfilter will store the iteration state. Must
762 * point to NULL to start the iteration.
763 *
764 * @return the next registered filter or NULL when the iteration is
765 * finished
766 */
768
769/**
770 * Get a filter definition matching the given name.
771 *
772 * @param name the filter name to find
773 * @return the filter definition, if any matching one is registered.
774 * NULL if none found.
775 */
776const AVFilter *avfilter_get_by_name(const char *name);
777
778
779/**
780 * Initialize a filter with the supplied parameters.
781 *
782 * @param ctx uninitialized filter context to initialize
783 * @param args Options to initialize the filter with. This must be a
784 * ':'-separated list of options in the 'key=value' form.
785 * May be NULL if the options have been set directly using the
786 * AVOptions API or there are no options that need to be set.
787 * @return 0 on success, a negative AVERROR on failure
788 */
789int avfilter_init_str(AVFilterContext *ctx, const char *args);
790
791/**
792 * Initialize a filter with the supplied dictionary of options.
793 *
794 * @param ctx uninitialized filter context to initialize
795 * @param options An AVDictionary filled with options for this filter. On
796 * return this parameter will be destroyed and replaced with
797 * a dict containing options that were not found. This dictionary
798 * must be freed by the caller.
799 * May be NULL, then this function is equivalent to
800 * avfilter_init_str() with the second parameter set to NULL.
801 * @return 0 on success, a negative AVERROR on failure
802 *
803 * @note This function and avfilter_init_str() do essentially the same thing,
804 * the difference is in manner in which the options are passed. It is up to the
805 * calling code to choose whichever is more preferable. The two functions also
806 * behave differently when some of the provided options are not declared as
807 * supported by the filter. In such a case, avfilter_init_str() will fail, but
808 * this function will leave those extra options in the options AVDictionary and
809 * continue as usual.
810 */
812
813/**
814 * Free a filter context. This will also remove the filter from its
815 * filtergraph's list of filters.
816 *
817 * @param filter the filter to free
818 */
820
821/**
822 * Insert a filter in the middle of an existing link.
823 *
824 * @param link the link into which the filter should be inserted
825 * @param filt the filter to be inserted
826 * @param filt_srcpad_idx the input pad on the filter to connect
827 * @param filt_dstpad_idx the output pad on the filter to connect
828 * @return zero on success
829 */
831 unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
832
833/**
834 * @return AVClass for AVFilterContext.
835 *
836 * @see av_opt_find().
837 */
839
841
842/**
843 * A function pointer passed to the @ref AVFilterGraph.execute callback to be
844 * executed multiple times, possibly in parallel.
845 *
846 * @param ctx the filter context the job belongs to
847 * @param arg an opaque parameter passed through from @ref
848 * AVFilterGraph.execute
849 * @param jobnr the index of the job being executed
850 * @param nb_jobs the total number of jobs
851 *
852 * @return 0 on success, a negative AVERROR on error
853 */
854typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
855
856/**
857 * A function executing multiple jobs, possibly in parallel.
858 *
859 * @param ctx the filter context to which the jobs belong
860 * @param func the function to be called multiple times
861 * @param arg the argument to be passed to func
862 * @param ret a nb_jobs-sized array to be filled with return values from each
863 * invocation of func
864 * @param nb_jobs the number of jobs to execute
865 *
866 * @return 0 on success, a negative AVERROR on error
867 */
869 void *arg, int *ret, int nb_jobs);
870
871typedef struct AVFilterGraph {
874 unsigned nb_filters;
875
876 char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
877
878 /**
879 * Type of multithreading allowed for filters in this graph. A combination
880 * of AVFILTER_THREAD_* flags.
881 *
882 * May be set by the caller at any point, the setting will apply to all
883 * filters initialized after that. The default is allowing everything.
884 *
885 * When a filter in this graph is initialized, this field is combined using
886 * bit AND with AVFilterContext.thread_type to get the final mask used for
887 * determining allowed threading types. I.e. a threading type needs to be
888 * set in both to be allowed.
889 */
891
892 /**
893 * Maximum number of threads used by filters in this graph. May be set by
894 * the caller before adding any filters to the filtergraph. Zero (the
895 * default) means that the number of threads is determined automatically.
896 */
898
899 /**
900 * Opaque object for libavfilter internal use.
901 */
903
904 /**
905 * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
906 * be used from callbacks like @ref AVFilterGraph.execute.
907 * Libavfilter will not touch this field in any way.
908 */
909 void *opaque;
910
911 /**
912 * This callback may be set by the caller immediately after allocating the
913 * graph and before adding any filters to it, to provide a custom
914 * multithreading implementation.
915 *
916 * If set, filters with slice threading capability will call this callback
917 * to execute multiple jobs in parallel.
918 *
919 * If this field is left unset, libavfilter will use its internal
920 * implementation, which may or may not be multithreaded depending on the
921 * platform and build options.
922 */
924
925 char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
926
927 /**
928 * Private fields
929 *
930 * The following fields are for internal use only.
931 * Their type, offset, number and semantic can change without notice.
932 */
933
936
939
940/**
941 * Allocate a filter graph.
942 *
943 * @return the allocated filter graph on success or NULL.
944 */
946
947/**
948 * Create a new filter instance in a filter graph.
949 *
950 * @param graph graph in which the new filter will be used
951 * @param filter the filter to create an instance of
952 * @param name Name to give to the new instance (will be copied to
953 * AVFilterContext.name). This may be used by the caller to identify
954 * different filters, libavfilter itself assigns no semantics to
955 * this parameter. May be NULL.
956 *
957 * @return the context of the newly created filter instance (note that it is
958 * also retrievable directly through AVFilterGraph.filters or with
959 * avfilter_graph_get_filter()) on success or NULL on failure.
960 */
962 const AVFilter *filter,
963 const char *name);
964
965/**
966 * Get a filter instance identified by instance name from graph.
967 *
968 * @param graph filter graph to search through.
969 * @param name filter instance name (should be unique in the graph).
970 * @return the pointer to the found filter instance or NULL if it
971 * cannot be found.
972 */
974
975/**
976 * Create and add a filter instance into an existing graph.
977 * The filter instance is created from the filter filt and inited
978 * with the parameter args. opaque is currently ignored.
979 *
980 * In case of success put in *filt_ctx the pointer to the created
981 * filter instance, otherwise set *filt_ctx to NULL.
982 *
983 * @param name the instance name to give to the created filter instance
984 * @param graph_ctx the filter graph
985 * @return a negative AVERROR error code in case of failure, a non
986 * negative value otherwise
987 */
989 const char *name, const char *args, void *opaque,
990 AVFilterGraph *graph_ctx);
991
992/**
993 * Enable or disable automatic format conversion inside the graph.
994 *
995 * Note that format conversion can still happen inside explicitly inserted
996 * scale and aresample filters.
997 *
998 * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
999 */
1001
1002enum {
1003 AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
1004 AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
1005};
1006
1007/**
1008 * Check validity and configure all the links and formats in the graph.
1009 *
1010 * @param graphctx the filter graph
1011 * @param log_ctx context used for logging
1012 * @return >= 0 in case of success, a negative AVERROR code otherwise
1013 */
1014int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1015
1016/**
1017 * Free a graph, destroy its links, and set *graph to NULL.
1018 * If *graph is NULL, do nothing.
1019 */
1021
1022/**
1023 * A linked-list of the inputs/outputs of the filter chain.
1024 *
1025 * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1026 * where it is used to communicate open (unlinked) inputs and outputs from and
1027 * to the caller.
1028 * This struct specifies, per each not connected pad contained in the graph, the
1029 * filter context and the pad index required for establishing a link.
1030 */
1031typedef struct AVFilterInOut {
1032 /** unique name for this input/output in the list */
1033 char *name;
1034
1035 /** filter context associated to this input/output */
1037
1038 /** index of the filt_ctx pad to use for linking */
1040
1041 /** next input/input in the list, NULL if this is the last */
1044
1045/**
1046 * Allocate a single AVFilterInOut entry.
1047 * Must be freed with avfilter_inout_free().
1048 * @return allocated AVFilterInOut on success, NULL on failure.
1049 */
1051
1052/**
1053 * Free the supplied list of AVFilterInOut and set *inout to NULL.
1054 * If *inout is NULL, do nothing.
1055 */
1057
1058/**
1059 * Add a graph described by a string to a graph.
1060 *
1061 * @note The caller must provide the lists of inputs and outputs,
1062 * which therefore must be known before calling the function.
1063 *
1064 * @note The inputs parameter describes inputs of the already existing
1065 * part of the graph; i.e. from the point of view of the newly created
1066 * part, they are outputs. Similarly the outputs parameter describes
1067 * outputs of the already existing filters, which are provided as
1068 * inputs to the parsed filters.
1069 *
1070 * @param graph the filter graph where to link the parsed graph context
1071 * @param filters string to be parsed
1072 * @param inputs linked list to the inputs of the graph
1073 * @param outputs linked list to the outputs of the graph
1074 * @return zero on success, a negative AVERROR code on error
1075 */
1076int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1077 AVFilterInOut *inputs, AVFilterInOut *outputs,
1078 void *log_ctx);
1079
1080/**
1081 * Add a graph described by a string to a graph.
1082 *
1083 * In the graph filters description, if the input label of the first
1084 * filter is not specified, "in" is assumed; if the output label of
1085 * the last filter is not specified, "out" is assumed.
1086 *
1087 * @param graph the filter graph where to link the parsed graph context
1088 * @param filters string to be parsed
1089 * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1090 * If non-NULL, *inputs is updated to contain the list of open inputs
1091 * after the parsing, should be freed with avfilter_inout_free().
1092 * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1093 * If non-NULL, *outputs is updated to contain the list of open outputs
1094 * after the parsing, should be freed with avfilter_inout_free().
1095 * @return non negative on success, a negative AVERROR code on error
1096 */
1097int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1098 AVFilterInOut **inputs, AVFilterInOut **outputs,
1099 void *log_ctx);
1100
1101/**
1102 * Add a graph described by a string to a graph.
1103 *
1104 * @param[in] graph the filter graph where to link the parsed graph context
1105 * @param[in] filters string to be parsed
1106 * @param[out] inputs a linked list of all free (unlinked) inputs of the
1107 * parsed graph will be returned here. It is to be freed
1108 * by the caller using avfilter_inout_free().
1109 * @param[out] outputs a linked list of all free (unlinked) outputs of the
1110 * parsed graph will be returned here. It is to be freed by the
1111 * caller using avfilter_inout_free().
1112 * @return zero on success, a negative AVERROR code on error
1113 *
1114 * @note This function returns the inputs and outputs that are left
1115 * unlinked after parsing the graph and the caller then deals with
1116 * them.
1117 * @note This function makes no reference whatsoever to already
1118 * existing parts of the graph and the inputs parameter will on return
1119 * contain inputs of the newly parsed part of the graph. Analogously
1120 * the outputs parameter will contain outputs of the newly created
1121 * filters.
1122 */
1123int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1124 AVFilterInOut **inputs,
1125 AVFilterInOut **outputs);
1126
1127/**
1128 * Send a command to one or more filter instances.
1129 *
1130 * @param graph the filter graph
1131 * @param target the filter(s) to which the command should be sent
1132 * "all" sends to all filters
1133 * otherwise it can be a filter or filter instance name
1134 * which will send the command to all matching filters.
1135 * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1136 * @param arg the argument for the command
1137 * @param res a buffer with size res_size where the filter(s) can return a response.
1138 *
1139 * @returns >=0 on success otherwise an error code.
1140 * AVERROR(ENOSYS) on unsupported commands
1141 */
1142int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1143
1144/**
1145 * Queue a command for one or more filter instances.
1146 *
1147 * @param graph the filter graph
1148 * @param target the filter(s) to which the command should be sent
1149 * "all" sends to all filters
1150 * otherwise it can be a filter or filter instance name
1151 * which will send the command to all matching filters.
1152 * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1153 * @param arg the argument for the command
1154 * @param ts time at which the command should be sent to the filter
1155 *
1156 * @note As this executes commands after this function returns, no return code
1157 * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1158 */
1159int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1160
1161
1162/**
1163 * Dump a graph into a human-readable string representation.
1164 *
1165 * @param graph the graph to dump
1166 * @param options formatting options; currently ignored
1167 * @return a string, or NULL in case of memory allocation failure;
1168 * the string must be freed using av_free
1169 */
1170char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1171
1172/**
1173 * Request a frame on the oldest sink link.
1174 *
1175 * If the request returns AVERROR_EOF, try the next.
1176 *
1177 * Note that this function is not meant to be the sole scheduling mechanism
1178 * of a filtergraph, only a convenience function to help drain a filtergraph
1179 * in a balanced way under normal circumstances.
1180 *
1181 * Also note that AVERROR_EOF does not mean that frames did not arrive on
1182 * some of the sinks during the process.
1183 * When there are multiple sink links, in case the requested link
1184 * returns an EOF, this may cause a filter to flush pending frames
1185 * which are sent to another sink link, although unrequested.
1186 *
1187 * @return the return value of ff_request_frame(),
1188 * or AVERROR_EOF if all links returned AVERROR_EOF
1189 */
1191
1192/**
1193 * @}
1194 */
1195
1196#endif /* AVFILTER_AVFILTER_H */
Macro definitions for various function/variable attributes.
#define attribute_deprecated
Definition: attributes.h:100
Convenience header that includes libavutil's core.
refcounted data buffer API
Public dictionary API.
reference-counted frame API
struct AVFilterPad AVFilterPad
Definition: avfilter.h:75
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt, unsigned filt_srcpad_idx, unsigned filt_dstpad_idx)
Insert a filter in the middle of an existing link.
void avfilter_free(AVFilterContext *filter)
Free a filter context.
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
attribute_deprecated int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in an AVFilter's inputs or outputs array.
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts)
Queue a command for one or more filter instances.
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs, void *log_ctx)
Add a graph described by a string to a graph.
AVFilterContext * avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
Get a filter instance identified by instance name from graph.
unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output)
Get the number of elements in an AVFilter's inputs or outputs array.
AVFilterContext * avfilter_graph_alloc_filter(AVFilterGraph *graph, const AVFilter *filter, const char *name)
Create a new filter instance in a filter graph.
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs)
Add a graph described by a string to a graph.
int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags)
Make the filter instance process a command.
struct AVFilterInternal AVFilterInternal
Definition: avfilter.h:405
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
const char * avfilter_license(void)
Return the libavfilter license.
struct AVFilterChannelLayouts AVFilterChannelLayouts
Definition: avfilter.h:77
int() avfilter_action_func(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
A function pointer passed to the AVFilterGraph::execute callback to be executed multiple times,...
Definition: avfilter.h:854
int() avfilter_execute_func(AVFilterContext *ctx, avfilter_action_func *func, void *arg, int *ret, int nb_jobs)
A function executing multiple jobs, possibly in parallel.
Definition: avfilter.h:868
struct AVFilterGraphInternal AVFilterGraphInternal
Definition: avfilter.h:840
int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags)
Send a command to one or more filter instances.
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, AVFilterInOut *inputs, AVFilterInOut *outputs, void *log_ctx)
Add a graph described by a string to a graph.
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt, const char *name, const char *args, void *opaque, AVFilterGraph *graph_ctx)
Create and add a filter instance into an existing graph.
const AVClass * avfilter_get_class(void)
struct AVFilterFormats AVFilterFormats
Definition: avfilter.h:76
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
Enable or disable automatic format conversion inside the graph.
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:1004
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:1003
struct AVDictionary AVDictionary
Definition: dict.h:84
AVMediaType
Definition: avutil.h:199
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
Libavfilter version macros.
Libavfilter version macros.
pixel format definitions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
Utilties for rational number calculation.
A reference to a data buffer.
Definition: buffer.h:82
An AVChannelLayout holds information about the channel layout of audio data.
Describe the class of an AVClass context structure.
Definition: log.h:66
An instance of a filter.
Definition: avfilter.h:408
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:409
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:471
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:443
int extra_hw_frames
Sets the number of extra hardware frames which the filter will allocate on its output links for use i...
Definition: avfilter.h:494
char * name
name of this filter instance
Definition: avfilter.h:413
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:453
unsigned nb_inputs
number of input pads
Definition: avfilter.h:417
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:416
char * enable_str
enable expression string
Definition: avfilter.h:452
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:411
AVFilterInternal * internal
An opaque struct for libavfilter internal use.
Definition: avfilter.h:448
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:425
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:415
void * priv
private data for use by the filter
Definition: avfilter.h:423
unsigned nb_outputs
number of output pads
Definition: avfilter.h:421
unsigned ready
Ready status of the filter.
Definition: avfilter.h:478
struct AVFilterCommand * command_queue
Definition: avfilter.h:450
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:419
double * var_values
variable values for the enable expression
Definition: avfilter.h:454
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:455
AVBufferRef * hw_device_ctx
For filters which will create hardware frames, sets the device the filter should create them in.
Definition: avfilter.h:464
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:420
Lists of formats / etc.
Definition: avfilter.h:507
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition: avfilter.h:512
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:522
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:517
unsigned nb_filters
Definition: avfilter.h:874
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:934
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:876
AVFilterContext ** filters
Definition: avfilter.h:873
void * opaque
Opaque user data.
Definition: avfilter.h:909
char * aresample_swr_opts
swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
Definition: avfilter.h:925
AVFilterGraphInternal * internal
Opaque object for libavfilter internal use.
Definition: avfilter.h:902
unsigned disable_auto_convert
Definition: avfilter.h:937
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:890
avfilter_execute_func * execute
This callback may be set by the caller immediately after allocating the graph and before adding any f...
Definition: avfilter.h:923
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:897
const AVClass * av_class
Definition: avfilter.h:872
int sink_links_count
Definition: avfilter.h:935
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1031
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1036
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:1039
char * name
unique name for this input/output in the list
Definition: avfilter.h:1033
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:1042
Filter definition.
Definition: avfilter.h:171
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:228
int(* process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags)
Make the filter instance process a command.
Definition: avfilter.h:378
const char * name
Filter name.
Definition: avfilter.h:175
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:359
int(* init_dict)(AVFilterContext *ctx, AVDictionary **options)
Should be set instead of init by the filters that want to pass a dictionary of AVOptions to nested co...
Definition: avfilter.h:290
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:302
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:329
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:215
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:239
union AVFilter::@1 formats
The state of the following union is determined by formats_state.
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:254
enum AVSampleFormat * samples_list
Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE and restricted to filters that only have AVM...
Definition: avfilter.h:351
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:364
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:210
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:233
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:362
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:277
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:200
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:191
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:355
enum AVPixelFormat * pixels_list
A pointer to an array of admissible pixel formats delimited by AV_PIX_FMT_NONE.
Definition: avfilter.h:340
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:392
const char * description
A description of the filter.
Definition: avfilter.h:182
Rational number (pair of numerator and denominator).
Definition: rational.h:58