FFmpeg 4.4.5
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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
50#include "libavfilter/version.h"
51
52/**
53 * Return the LIBAVFILTER_VERSION_INT constant.
54 */
55unsigned avfilter_version(void);
56
57/**
58 * Return the libavfilter build-time configuration.
59 */
60const char *avfilter_configuration(void);
61
62/**
63 * Return the libavfilter license.
64 */
65const char *avfilter_license(void);
66
67typedef struct AVFilterContext AVFilterContext;
68typedef struct AVFilterLink AVFilterLink;
69typedef struct AVFilterPad AVFilterPad;
72
73/**
74 * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
75 * AVFilter.inputs/outputs).
76 */
78
79/**
80 * Get the name of an AVFilterPad.
81 *
82 * @param pads an array of AVFilterPads
83 * @param pad_idx index of the pad in the array; it is the caller's
84 * responsibility to ensure the index is valid
85 *
86 * @return name of the pad_idx'th pad in pads
87 */
88const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
89
90/**
91 * Get the type of an AVFilterPad.
92 *
93 * @param pads an array of AVFilterPads
94 * @param pad_idx index of the pad in the array; it is the caller's
95 * responsibility to ensure the index is valid
96 *
97 * @return type of the pad_idx'th pad in pads
98 */
99enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
100
101/**
102 * The number of the filter inputs is not determined just by AVFilter.inputs.
103 * The filter might add additional inputs during initialization depending on the
104 * options supplied to it.
105 */
106#define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
107/**
108 * The number of the filter outputs is not determined just by AVFilter.outputs.
109 * The filter might add additional outputs during initialization depending on
110 * the options supplied to it.
111 */
112#define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
113/**
114 * The filter supports multithreading by splitting frames into multiple parts
115 * and processing them concurrently.
116 */
117#define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
118/**
119 * Some filters support a generic "enable" expression option that can be used
120 * to enable or disable a filter in the timeline. Filters supporting this
121 * option have this flag set. When the enable expression is false, the default
122 * no-op filter_frame() function is called in place of the filter_frame()
123 * callback defined on each input pad, thus the frame is passed unchanged to
124 * the next filters.
125 */
126#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
127/**
128 * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
129 * have its filter_frame() callback(s) called as usual even when the enable
130 * expression is false. The filter will disable filtering within the
131 * filter_frame() callback(s) itself, for example executing code depending on
132 * the AVFilterContext->is_disabled value.
133 */
134#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
135/**
136 * Handy mask to test whether the filter supports or no the timeline feature
137 * (internally or generically).
138 */
139#define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
140
141/**
142 * Filter definition. This defines the pads a filter contains, and all the
143 * callback functions used to interact with the filter.
144 */
145typedef struct AVFilter {
146 /**
147 * Filter name. Must be non-NULL and unique among filters.
148 */
149 const char *name;
150
151 /**
152 * A description of the filter. May be NULL.
153 *
154 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
155 */
156 const char *description;
157
158 /**
159 * List of inputs, terminated by a zeroed element.
160 *
161 * NULL if there are no (static) inputs. Instances of filters with
162 * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
163 * this list.
164 */
166 /**
167 * List of outputs, terminated by a zeroed element.
168 *
169 * NULL if there are no (static) outputs. Instances of filters with
170 * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
171 * this list.
172 */
174
175 /**
176 * A class for the private data, used to declare filter private AVOptions.
177 * This field is NULL for filters that do not declare any options.
178 *
179 * If this field is non-NULL, the first member of the filter private data
180 * must be a pointer to AVClass, which will be set by libavfilter generic
181 * code to this class.
182 */
184
185 /**
186 * A combination of AVFILTER_FLAG_*
187 */
188 int flags;
189
190 /*****************************************************************
191 * All fields below this line are not part of the public API. They
192 * may not be used outside of libavfilter and can be changed and
193 * removed at will.
194 * New public fields should be added right above.
195 *****************************************************************
196 */
197
198 /**
199 * Filter pre-initialization function
200 *
201 * This callback will be called immediately after the filter context is
202 * allocated, to allow allocating and initing sub-objects.
203 *
204 * If this callback is not NULL, the uninit callback will be called on
205 * allocation failure.
206 *
207 * @return 0 on success,
208 * AVERROR code on failure (but the code will be
209 * dropped and treated as ENOMEM by the calling code)
210 */
212
213 /**
214 * Filter initialization function.
215 *
216 * This callback will be called only once during the filter lifetime, after
217 * all the options have been set, but before links between filters are
218 * established and format negotiation is done.
219 *
220 * Basic filter initialization should be done here. Filters with dynamic
221 * inputs and/or outputs should create those inputs/outputs here based on
222 * provided options. No more changes to this filter's inputs/outputs can be
223 * done after this callback.
224 *
225 * This callback must not assume that the filter links exist or frame
226 * parameters are known.
227 *
228 * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
229 * initialization fails, so this callback does not have to clean up on
230 * failure.
231 *
232 * @return 0 on success, a negative AVERROR on failure
233 */
234 int (*init)(AVFilterContext *ctx);
235
236 /**
237 * Should be set instead of @ref AVFilter.init "init" by the filters that
238 * want to pass a dictionary of AVOptions to nested contexts that are
239 * allocated during init.
240 *
241 * On return, the options dict should be freed and replaced with one that
242 * contains all the options which could not be processed by this filter (or
243 * with NULL if all the options were processed).
244 *
245 * Otherwise the semantics is the same as for @ref AVFilter.init "init".
246 */
247 int (*init_dict)(AVFilterContext *ctx, AVDictionary **options);
248
249 /**
250 * Filter uninitialization function.
251 *
252 * Called only once right before the filter is freed. Should deallocate any
253 * memory held by the filter, release any buffer references, etc. It does
254 * not need to deallocate the AVFilterContext.priv memory itself.
255 *
256 * This callback may be called even if @ref AVFilter.init "init" was not
257 * called or failed, so it must be prepared to handle such a situation.
258 */
259 void (*uninit)(AVFilterContext *ctx);
260
261 /**
262 * Query formats supported by the filter on its inputs and outputs.
263 *
264 * This callback is called after the filter is initialized (so the inputs
265 * and outputs are fixed), shortly before the format negotiation. This
266 * callback may be called more than once.
267 *
268 * This callback must set AVFilterLink.outcfg.formats on every input link and
269 * AVFilterLink.incfg.formats on every output link to a list of pixel/sample
270 * formats that the filter supports on that link. For audio links, this
271 * filter must also set @ref AVFilterLink.incfg.samplerates "in_samplerates" /
272 * @ref AVFilterLink.outcfg.samplerates "out_samplerates" and
273 * @ref AVFilterLink.incfg.channel_layouts "in_channel_layouts" /
274 * @ref AVFilterLink.outcfg.channel_layouts "out_channel_layouts" analogously.
275 *
276 * This callback may be NULL for filters with one input, in which case
277 * libavfilter assumes that it supports all input formats and preserves
278 * them on output.
279 *
280 * @return zero on success, a negative value corresponding to an
281 * AVERROR code otherwise
282 */
284
285 int priv_size; ///< size of private data to allocate for the filter
286
287 int flags_internal; ///< Additional flags for avfilter internal use only.
288
289#if FF_API_NEXT
290 /**
291 * Used by the filter registration system. Must not be touched by any other
292 * code.
293 */
294 struct AVFilter *next;
295#endif
296
297 /**
298 * Make the filter instance process a command.
299 *
300 * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
301 * @param arg the argument for the command
302 * @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.
303 * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
304 * time consuming then a filter should treat it like an unsupported command
305 *
306 * @returns >=0 on success otherwise an error code.
307 * AVERROR(ENOSYS) on unsupported commands
308 */
309 int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
310
311 /**
312 * Filter initialization function, alternative to the init()
313 * callback. Args contains the user-supplied parameters, opaque is
314 * used for providing binary data.
315 */
316 int (*init_opaque)(AVFilterContext *ctx, void *opaque);
317
318 /**
319 * Filter activation function.
320 *
321 * Called when any processing is needed from the filter, instead of any
322 * filter_frame and request_frame on pads.
323 *
324 * The function must examine inlinks and outlinks and perform a single
325 * step of processing. If there is nothing to do, the function must do
326 * nothing and not return an error. If more steps are or may be
327 * possible, it must use ff_filter_set_ready() to schedule another
328 * activation.
329 */
331} AVFilter;
332
333/**
334 * Process multiple parts of the frame concurrently.
335 */
336#define AVFILTER_THREAD_SLICE (1 << 0)
337
339
340/** An instance of a filter */
342 const AVClass *av_class; ///< needed for av_log() and filters common options
343
344 const AVFilter *filter; ///< the AVFilter of which this is an instance
345
346 char *name; ///< name of this filter instance
347
348 AVFilterPad *input_pads; ///< array of input pads
349 AVFilterLink **inputs; ///< array of pointers to input links
350 unsigned nb_inputs; ///< number of input pads
351
352 AVFilterPad *output_pads; ///< array of output pads
353 AVFilterLink **outputs; ///< array of pointers to output links
354 unsigned nb_outputs; ///< number of output pads
355
356 void *priv; ///< private data for use by the filter
357
358 struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
359
360 /**
361 * Type of multithreading being allowed/used. A combination of
362 * AVFILTER_THREAD_* flags.
363 *
364 * May be set by the caller before initializing the filter to forbid some
365 * or all kinds of multithreading for this filter. The default is allowing
366 * everything.
367 *
368 * When the filter is initialized, this field is combined using bit AND with
369 * AVFilterGraph.thread_type to get the final mask used for determining
370 * allowed threading types. I.e. a threading type needs to be set in both
371 * to be allowed.
372 *
373 * After the filter is initialized, libavfilter sets this field to the
374 * threading type that is actually used (0 for no multithreading).
375 */
377
378 /**
379 * An opaque struct for libavfilter internal use.
380 */
382
383 struct AVFilterCommand *command_queue;
384
385 char *enable_str; ///< enable expression string
386 void *enable; ///< parsed expression (AVExpr*)
387 double *var_values; ///< variable values for the enable expression
388 int is_disabled; ///< the enabled state from the last expression evaluation
389
390 /**
391 * For filters which will create hardware frames, sets the device the
392 * filter should create them in. All other filters will ignore this field:
393 * in particular, a filter which consumes or processes hardware frames will
394 * instead use the hw_frames_ctx field in AVFilterLink to carry the
395 * hardware context information.
396 */
398
399 /**
400 * Max number of threads allowed in this filter instance.
401 * If <= 0, its value is ignored.
402 * Overrides global number of threads set per filter graph.
403 */
405
406 /**
407 * Ready status of the filter.
408 * A non-0 value means that the filter needs activating;
409 * a higher value suggests a more urgent activation.
410 */
411 unsigned ready;
412
413 /**
414 * Sets the number of extra hardware frames which the filter will
415 * allocate on its output links for use in following filters or by
416 * the caller.
417 *
418 * Some hardware filters require all frames that they will use for
419 * output to be defined in advance before filtering starts. For such
420 * filters, any hardware frame pools used for output must therefore be
421 * of fixed size. The extra frames set here are on top of any number
422 * that the filter needs internally in order to operate normally.
423 *
424 * This field must be set before the graph containing this filter is
425 * configured.
426 */
428};
429
430/**
431 * Lists of formats / etc. supported by an end of a link.
432 *
433 * This structure is directly part of AVFilterLink, in two copies:
434 * one for the source filter, one for the destination filter.
435
436 * These lists are used for negotiating the format to actually be used,
437 * which will be loaded into the format and channel_layout members of
438 * AVFilterLink, when chosen.
439 */
440typedef struct AVFilterFormatsConfig {
441
442 /**
443 * List of supported formats (pixel or sample).
444 */
446
447 /**
448 * Lists of supported sample rates, only for audio.
449 */
451
452 /**
453 * Lists of supported channel layouts, only for audio.
454 */
456
458
459/**
460 * A link between two filters. This contains pointers to the source and
461 * destination filters between which this link exists, and the indexes of
462 * the pads involved. In addition, this link also contains the parameters
463 * which have been negotiated and agreed upon between the filter, such as
464 * image dimensions, format, etc.
465 *
466 * Applications must not normally access the link structure directly.
467 * Use the buffersrc and buffersink API instead.
468 * In the future, access to the header may be reserved for filters
469 * implementation.
470 */
472 AVFilterContext *src; ///< source filter
473 AVFilterPad *srcpad; ///< output pad on the source filter
474
475 AVFilterContext *dst; ///< dest filter
476 AVFilterPad *dstpad; ///< input pad on the dest filter
477
478 enum AVMediaType type; ///< filter media type
479
480 /* These parameters apply only to video */
481 int w; ///< agreed upon image width
482 int h; ///< agreed upon image height
483 AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
484 /* These parameters apply only to audio */
485 uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
486 int sample_rate; ///< samples per second
487
488 int format; ///< agreed upon media format
489
490 /**
491 * Define the time base used by the PTS of the frames/samples
492 * which will pass through this link.
493 * During the configuration stage, each filter is supposed to
494 * change only the output timebase, while the timebase of the
495 * input link is assumed to be an unchangeable property.
496 */
498
499 /*****************************************************************
500 * All fields below this line are not part of the public API. They
501 * may not be used outside of libavfilter and can be changed and
502 * removed at will.
503 * New public fields should be added right above.
504 *****************************************************************
505 */
506
507 /**
508 * Lists of supported formats / etc. supported by the input filter.
509 */
511
512 /**
513 * Lists of supported formats / etc. supported by the output filter.
514 */
516
517 /** stage of the initialization of the link properties (dimensions, etc) */
518 enum {
519 AVLINK_UNINIT = 0, ///< not started
520 AVLINK_STARTINIT, ///< started, but incomplete
521 AVLINK_INIT ///< complete
523
524 /**
525 * Graph the filter belongs to.
526 */
528
529 /**
530 * Current timestamp of the link, as defined by the most recent
531 * frame(s), in link time_base units.
532 */
533 int64_t current_pts;
534
535 /**
536 * Current timestamp of the link, as defined by the most recent
537 * frame(s), in AV_TIME_BASE units.
538 */
540
541 /**
542 * Index in the age array.
543 */
545
546 /**
547 * Frame rate of the stream on the link, or 1/0 if unknown or variable;
548 * if left to 0/0, will be automatically copied from the first input
549 * of the source filter if it exists.
550 *
551 * Sources should set it to the best estimation of the real frame rate.
552 * If the source frame rate is unknown or variable, set this to 1/0.
553 * Filters should update it if necessary depending on their function.
554 * Sinks can use it to set a default output frame rate.
555 * It is similar to the r_frame_rate field in AVStream.
556 */
558
559 /**
560 * Buffer partially filled with samples to achieve a fixed/minimum size.
561 */
563
564 /**
565 * Size of the partial buffer to allocate.
566 * Must be between min_samples and max_samples.
567 */
569
570 /**
571 * Minimum number of samples to filter at once. If filter_frame() is
572 * called with fewer samples, it will accumulate them in partial_buf.
573 * This field and the related ones must not be changed after filtering
574 * has started.
575 * If 0, all related fields are ignored.
576 */
578
579 /**
580 * Maximum number of samples to filter at once. If filter_frame() is
581 * called with more samples, it will split them.
582 */
584
585 /**
586 * Number of channels.
587 */
589
590 /**
591 * Number of past frames sent through the link.
592 */
594
595 /**
596 * A pointer to a FFFramePool struct.
597 */
599
600 /**
601 * True if a frame is currently wanted on the output of this filter.
602 * Set when ff_request_frame() is called by the output,
603 * cleared when a frame is filtered.
604 */
606
607 /**
608 * For hwaccel pixel formats, this should be a reference to the
609 * AVHWFramesContext describing the frames.
610 */
612
613#ifndef FF_INTERNAL_FIELDS
614
615 /**
616 * Internal structure members.
617 * The fields below this limit are internal for libavfilter's use
618 * and must in no way be accessed by applications.
619 */
620 char reserved[0xF000];
621
622#else /* FF_INTERNAL_FIELDS */
623
624 /**
625 * Queue of frames waiting to be filtered.
626 */
627 FFFrameQueue fifo;
628
629 /**
630 * If set, the source filter can not generate a frame as is.
631 * The goal is to avoid repeatedly calling the request_frame() method on
632 * the same link.
633 */
634 int frame_blocked_in;
635
636 /**
637 * Link input status.
638 * If not zero, all attempts of filter_frame will fail with the
639 * corresponding code.
640 */
641 int status_in;
642
643 /**
644 * Timestamp of the input status change.
645 */
646 int64_t status_in_pts;
647
648 /**
649 * Link output status.
650 * If not zero, all attempts of request_frame will fail with the
651 * corresponding code.
652 */
653 int status_out;
654
655#endif /* FF_INTERNAL_FIELDS */
656
657};
658
659/**
660 * Link two filters together.
661 *
662 * @param src the source filter
663 * @param srcpad index of the output pad on the source filter
664 * @param dst the destination filter
665 * @param dstpad index of the input pad on the destination filter
666 * @return zero on success
667 */
668int avfilter_link(AVFilterContext *src, unsigned srcpad,
669 AVFilterContext *dst, unsigned dstpad);
670
671/**
672 * Free the link in *link, and set its pointer to NULL.
673 */
675
676#if FF_API_FILTER_GET_SET
677/**
678 * Get the number of channels of a link.
679 * @deprecated Use av_buffersink_get_channels()
680 */
682int avfilter_link_get_channels(AVFilterLink *link);
683#endif
684#if FF_API_FILTER_LINK_SET_CLOSED
685/**
686 * Set the closed field of a link.
687 * @deprecated applications are not supposed to mess with links, they should
688 * close the sinks.
689 */
691void avfilter_link_set_closed(AVFilterLink *link, int closed);
692#endif
693/**
694 * Negotiate the media format, dimensions, etc of all inputs to a filter.
695 *
696 * @param filter the filter to negotiate the properties for its inputs
697 * @return zero on successful negotiation
698 */
700
701#define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
702#define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
703
704/**
705 * Make the filter instance process a command.
706 * It is recommended to use avfilter_graph_send_command().
707 */
708int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
709
710/**
711 * Iterate over all registered filters.
712 *
713 * @param opaque a pointer where libavfilter will store the iteration state. Must
714 * point to NULL to start the iteration.
715 *
716 * @return the next registered filter or NULL when the iteration is
717 * finished
718 */
720
721#if FF_API_NEXT
722/** Initialize the filter system. Register all builtin filters. */
724void avfilter_register_all(void);
725
726/**
727 * Register a filter. This is only needed if you plan to use
728 * avfilter_get_by_name later to lookup the AVFilter structure by name. A
729 * filter can still by instantiated with avfilter_graph_alloc_filter even if it
730 * is not registered.
731 *
732 * @param filter the filter to register
733 * @return 0 if the registration was successful, a negative value
734 * otherwise
735 */
737int avfilter_register(AVFilter *filter);
738
739/**
740 * Iterate over all registered filters.
741 * @return If prev is non-NULL, next registered filter after prev or NULL if
742 * prev is the last filter. If prev is NULL, return the first registered filter.
743 */
745const AVFilter *avfilter_next(const AVFilter *prev);
746#endif
747
748/**
749 * Get a filter definition matching the given name.
750 *
751 * @param name the filter name to find
752 * @return the filter definition, if any matching one is registered.
753 * NULL if none found.
754 */
755const AVFilter *avfilter_get_by_name(const char *name);
756
757
758/**
759 * Initialize a filter with the supplied parameters.
760 *
761 * @param ctx uninitialized filter context to initialize
762 * @param args Options to initialize the filter with. This must be a
763 * ':'-separated list of options in the 'key=value' form.
764 * May be NULL if the options have been set directly using the
765 * AVOptions API or there are no options that need to be set.
766 * @return 0 on success, a negative AVERROR on failure
767 */
768int avfilter_init_str(AVFilterContext *ctx, const char *args);
769
770/**
771 * Initialize a filter with the supplied dictionary of options.
772 *
773 * @param ctx uninitialized filter context to initialize
774 * @param options An AVDictionary filled with options for this filter. On
775 * return this parameter will be destroyed and replaced with
776 * a dict containing options that were not found. This dictionary
777 * must be freed by the caller.
778 * May be NULL, then this function is equivalent to
779 * avfilter_init_str() with the second parameter set to NULL.
780 * @return 0 on success, a negative AVERROR on failure
781 *
782 * @note This function and avfilter_init_str() do essentially the same thing,
783 * the difference is in manner in which the options are passed. It is up to the
784 * calling code to choose whichever is more preferable. The two functions also
785 * behave differently when some of the provided options are not declared as
786 * supported by the filter. In such a case, avfilter_init_str() will fail, but
787 * this function will leave those extra options in the options AVDictionary and
788 * continue as usual.
789 */
791
792/**
793 * Free a filter context. This will also remove the filter from its
794 * filtergraph's list of filters.
795 *
796 * @param filter the filter to free
797 */
799
800/**
801 * Insert a filter in the middle of an existing link.
802 *
803 * @param link the link into which the filter should be inserted
804 * @param filt the filter to be inserted
805 * @param filt_srcpad_idx the input pad on the filter to connect
806 * @param filt_dstpad_idx the output pad on the filter to connect
807 * @return zero on success
808 */
810 unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
811
812/**
813 * @return AVClass for AVFilterContext.
814 *
815 * @see av_opt_find().
816 */
818
820
821/**
822 * A function pointer passed to the @ref AVFilterGraph.execute callback to be
823 * executed multiple times, possibly in parallel.
824 *
825 * @param ctx the filter context the job belongs to
826 * @param arg an opaque parameter passed through from @ref
827 * AVFilterGraph.execute
828 * @param jobnr the index of the job being executed
829 * @param nb_jobs the total number of jobs
830 *
831 * @return 0 on success, a negative AVERROR on error
832 */
833typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
834
835/**
836 * A function executing multiple jobs, possibly in parallel.
837 *
838 * @param ctx the filter context to which the jobs belong
839 * @param func the function to be called multiple times
840 * @param arg the argument to be passed to func
841 * @param ret a nb_jobs-sized array to be filled with return values from each
842 * invocation of func
843 * @param nb_jobs the number of jobs to execute
844 *
845 * @return 0 on success, a negative AVERROR on error
846 */
848 void *arg, int *ret, int nb_jobs);
849
850typedef struct AVFilterGraph {
853 unsigned nb_filters;
854
855 char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
856#if FF_API_LAVR_OPTS
857 attribute_deprecated char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters
858#endif
859
860 /**
861 * Type of multithreading allowed for filters in this graph. A combination
862 * of AVFILTER_THREAD_* flags.
863 *
864 * May be set by the caller at any point, the setting will apply to all
865 * filters initialized after that. The default is allowing everything.
866 *
867 * When a filter in this graph is initialized, this field is combined using
868 * bit AND with AVFilterContext.thread_type to get the final mask used for
869 * determining allowed threading types. I.e. a threading type needs to be
870 * set in both to be allowed.
871 */
873
874 /**
875 * Maximum number of threads used by filters in this graph. May be set by
876 * the caller before adding any filters to the filtergraph. Zero (the
877 * default) means that the number of threads is determined automatically.
878 */
880
881 /**
882 * Opaque object for libavfilter internal use.
883 */
885
886 /**
887 * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
888 * be used from callbacks like @ref AVFilterGraph.execute.
889 * Libavfilter will not touch this field in any way.
890 */
891 void *opaque;
892
893 /**
894 * This callback may be set by the caller immediately after allocating the
895 * graph and before adding any filters to it, to provide a custom
896 * multithreading implementation.
897 *
898 * If set, filters with slice threading capability will call this callback
899 * to execute multiple jobs in parallel.
900 *
901 * If this field is left unset, libavfilter will use its internal
902 * implementation, which may or may not be multithreaded depending on the
903 * platform and build options.
904 */
906
907 char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
908
909 /**
910 * Private fields
911 *
912 * The following fields are for internal use only.
913 * Their type, offset, number and semantic can change without notice.
914 */
915
918
921
922/**
923 * Allocate a filter graph.
924 *
925 * @return the allocated filter graph on success or NULL.
926 */
928
929/**
930 * Create a new filter instance in a filter graph.
931 *
932 * @param graph graph in which the new filter will be used
933 * @param filter the filter to create an instance of
934 * @param name Name to give to the new instance (will be copied to
935 * AVFilterContext.name). This may be used by the caller to identify
936 * different filters, libavfilter itself assigns no semantics to
937 * this parameter. May be NULL.
938 *
939 * @return the context of the newly created filter instance (note that it is
940 * also retrievable directly through AVFilterGraph.filters or with
941 * avfilter_graph_get_filter()) on success or NULL on failure.
942 */
944 const AVFilter *filter,
945 const char *name);
946
947/**
948 * Get a filter instance identified by instance name from graph.
949 *
950 * @param graph filter graph to search through.
951 * @param name filter instance name (should be unique in the graph).
952 * @return the pointer to the found filter instance or NULL if it
953 * cannot be found.
954 */
956
957/**
958 * Create and add a filter instance into an existing graph.
959 * The filter instance is created from the filter filt and inited
960 * with the parameter args. opaque is currently ignored.
961 *
962 * In case of success put in *filt_ctx the pointer to the created
963 * filter instance, otherwise set *filt_ctx to NULL.
964 *
965 * @param name the instance name to give to the created filter instance
966 * @param graph_ctx the filter graph
967 * @return a negative AVERROR error code in case of failure, a non
968 * negative value otherwise
969 */
971 const char *name, const char *args, void *opaque,
972 AVFilterGraph *graph_ctx);
973
974/**
975 * Enable or disable automatic format conversion inside the graph.
976 *
977 * Note that format conversion can still happen inside explicitly inserted
978 * scale and aresample filters.
979 *
980 * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
981 */
983
984enum {
985 AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
986 AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
987};
988
989/**
990 * Check validity and configure all the links and formats in the graph.
991 *
992 * @param graphctx the filter graph
993 * @param log_ctx context used for logging
994 * @return >= 0 in case of success, a negative AVERROR code otherwise
995 */
996int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
997
998/**
999 * Free a graph, destroy its links, and set *graph to NULL.
1000 * If *graph is NULL, do nothing.
1001 */
1003
1004/**
1005 * A linked-list of the inputs/outputs of the filter chain.
1006 *
1007 * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1008 * where it is used to communicate open (unlinked) inputs and outputs from and
1009 * to the caller.
1010 * This struct specifies, per each not connected pad contained in the graph, the
1011 * filter context and the pad index required for establishing a link.
1012 */
1013typedef struct AVFilterInOut {
1014 /** unique name for this input/output in the list */
1015 char *name;
1016
1017 /** filter context associated to this input/output */
1019
1020 /** index of the filt_ctx pad to use for linking */
1022
1023 /** next input/input in the list, NULL if this is the last */
1026
1027/**
1028 * Allocate a single AVFilterInOut entry.
1029 * Must be freed with avfilter_inout_free().
1030 * @return allocated AVFilterInOut on success, NULL on failure.
1031 */
1033
1034/**
1035 * Free the supplied list of AVFilterInOut and set *inout to NULL.
1036 * If *inout is NULL, do nothing.
1037 */
1039
1040/**
1041 * Add a graph described by a string to a graph.
1042 *
1043 * @note The caller must provide the lists of inputs and outputs,
1044 * which therefore must be known before calling the function.
1045 *
1046 * @note The inputs parameter describes inputs of the already existing
1047 * part of the graph; i.e. from the point of view of the newly created
1048 * part, they are outputs. Similarly the outputs parameter describes
1049 * outputs of the already existing filters, which are provided as
1050 * inputs to the parsed filters.
1051 *
1052 * @param graph the filter graph where to link the parsed graph context
1053 * @param filters string to be parsed
1054 * @param inputs linked list to the inputs of the graph
1055 * @param outputs linked list to the outputs of the graph
1056 * @return zero on success, a negative AVERROR code on error
1057 */
1058int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1059 AVFilterInOut *inputs, AVFilterInOut *outputs,
1060 void *log_ctx);
1061
1062/**
1063 * Add a graph described by a string to a graph.
1064 *
1065 * In the graph filters description, if the input label of the first
1066 * filter is not specified, "in" is assumed; if the output label of
1067 * the last filter is not specified, "out" is assumed.
1068 *
1069 * @param graph the filter graph where to link the parsed graph context
1070 * @param filters string to be parsed
1071 * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1072 * If non-NULL, *inputs is updated to contain the list of open inputs
1073 * after the parsing, should be freed with avfilter_inout_free().
1074 * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1075 * If non-NULL, *outputs is updated to contain the list of open outputs
1076 * after the parsing, should be freed with avfilter_inout_free().
1077 * @return non negative on success, a negative AVERROR code on error
1078 */
1079int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1080 AVFilterInOut **inputs, AVFilterInOut **outputs,
1081 void *log_ctx);
1082
1083/**
1084 * Add a graph described by a string to a graph.
1085 *
1086 * @param[in] graph the filter graph where to link the parsed graph context
1087 * @param[in] filters string to be parsed
1088 * @param[out] inputs a linked list of all free (unlinked) inputs of the
1089 * parsed graph will be returned here. It is to be freed
1090 * by the caller using avfilter_inout_free().
1091 * @param[out] outputs a linked list of all free (unlinked) outputs of the
1092 * parsed graph will be returned here. It is to be freed by the
1093 * caller using avfilter_inout_free().
1094 * @return zero on success, a negative AVERROR code on error
1095 *
1096 * @note This function returns the inputs and outputs that are left
1097 * unlinked after parsing the graph and the caller then deals with
1098 * them.
1099 * @note This function makes no reference whatsoever to already
1100 * existing parts of the graph and the inputs parameter will on return
1101 * contain inputs of the newly parsed part of the graph. Analogously
1102 * the outputs parameter will contain outputs of the newly created
1103 * filters.
1104 */
1105int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1106 AVFilterInOut **inputs,
1107 AVFilterInOut **outputs);
1108
1109/**
1110 * Send a command to one or more filter instances.
1111 *
1112 * @param graph the filter graph
1113 * @param target the filter(s) to which the command should be sent
1114 * "all" sends to all filters
1115 * otherwise it can be a filter or filter instance name
1116 * which will send the command to all matching filters.
1117 * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1118 * @param arg the argument for the command
1119 * @param res a buffer with size res_size where the filter(s) can return a response.
1120 *
1121 * @returns >=0 on success otherwise an error code.
1122 * AVERROR(ENOSYS) on unsupported commands
1123 */
1124int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1125
1126/**
1127 * Queue a command for one or more filter instances.
1128 *
1129 * @param graph the filter graph
1130 * @param target the filter(s) to which the command should be sent
1131 * "all" sends to all filters
1132 * otherwise it can be a filter or filter instance name
1133 * which will send the command to all matching filters.
1134 * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1135 * @param arg the argument for the command
1136 * @param ts time at which the command should be sent to the filter
1137 *
1138 * @note As this executes commands after this function returns, no return code
1139 * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1140 */
1141int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1142
1143
1144/**
1145 * Dump a graph into a human-readable string representation.
1146 *
1147 * @param graph the graph to dump
1148 * @param options formatting options; currently ignored
1149 * @return a string, or NULL in case of memory allocation failure;
1150 * the string must be freed using av_free
1151 */
1152char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1153
1154/**
1155 * Request a frame on the oldest sink link.
1156 *
1157 * If the request returns AVERROR_EOF, try the next.
1158 *
1159 * Note that this function is not meant to be the sole scheduling mechanism
1160 * of a filtergraph, only a convenience function to help drain a filtergraph
1161 * in a balanced way under normal circumstances.
1162 *
1163 * Also note that AVERROR_EOF does not mean that frames did not arrive on
1164 * some of the sinks during the process.
1165 * When there are multiple sink links, in case the requested link
1166 * returns an EOF, this may cause a filter to flush pending frames
1167 * which are sent to another sink link, although unrequested.
1168 *
1169 * @return the return value of ff_request_frame(),
1170 * or AVERROR_EOF if all links returned AVERROR_EOF
1171 */
1173
1174/**
1175 * @}
1176 */
1177
1178#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:69
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.
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.
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:338
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:71
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:833
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:847
struct AVFilterGraphInternal AVFilterGraphInternal
Definition avfilter.h:819
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:70
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
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:986
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition avfilter.h:985
struct AVDictionary AVDictionary
Definition dict.h:86
AVMediaType
Definition avutil.h:199
Libavfilter version macros.
pixel format definitions
Utilties for rational number calculation.
A reference to a data buffer.
Definition buffer.h:84
Describe the class of an AVClass context structure.
Definition log.h:67
An instance of a filter.
Definition avfilter.h:341
const AVClass * av_class
needed for av_log() and filters common options
Definition avfilter.h:342
int nb_threads
Max number of threads allowed in this filter instance.
Definition avfilter.h:404
int thread_type
Type of multithreading being allowed/used.
Definition avfilter.h:376
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:427
char * name
name of this filter instance
Definition avfilter.h:346
void * enable
parsed expression (AVExpr*)
Definition avfilter.h:386
unsigned nb_inputs
number of input pads
Definition avfilter.h:350
AVFilterLink ** inputs
array of pointers to input links
Definition avfilter.h:349
char * enable_str
enable expression string
Definition avfilter.h:385
const AVFilter * filter
the AVFilter of which this is an instance
Definition avfilter.h:344
AVFilterInternal * internal
An opaque struct for libavfilter internal use.
Definition avfilter.h:381
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition avfilter.h:358
AVFilterPad * input_pads
array of input pads
Definition avfilter.h:348
void * priv
private data for use by the filter
Definition avfilter.h:356
unsigned nb_outputs
number of output pads
Definition avfilter.h:354
unsigned ready
Ready status of the filter.
Definition avfilter.h:411
struct AVFilterCommand * command_queue
Definition avfilter.h:383
AVFilterPad * output_pads
array of output pads
Definition avfilter.h:352
double * var_values
variable values for the enable expression
Definition avfilter.h:387
int is_disabled
the enabled state from the last expression evaluation
Definition avfilter.h:388
AVBufferRef * hw_device_ctx
For filters which will create hardware frames, sets the device the filter should create them in.
Definition avfilter.h:397
AVFilterLink ** outputs
array of pointers to output links
Definition avfilter.h:353
Lists of formats / etc.
Definition avfilter.h:440
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition avfilter.h:445
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition avfilter.h:455
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition avfilter.h:450
unsigned nb_filters
Definition avfilter.h:853
AVFilterLink ** sink_links
Private fields.
Definition avfilter.h:916
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition avfilter.h:855
AVFilterContext ** filters
Definition avfilter.h:852
void * opaque
Opaque user data.
Definition avfilter.h:891
char * aresample_swr_opts
swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
Definition avfilter.h:907
AVFilterGraphInternal * internal
Opaque object for libavfilter internal use.
Definition avfilter.h:884
unsigned disable_auto_convert
Definition avfilter.h:919
int thread_type
Type of multithreading allowed for filters in this graph.
Definition avfilter.h:872
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:905
int nb_threads
Maximum number of threads used by filters in this graph.
Definition avfilter.h:879
const AVClass * av_class
Definition avfilter.h:851
int sink_links_count
Definition avfilter.h:917
A linked-list of the inputs/outputs of the filter chain.
Definition avfilter.h:1013
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition avfilter.h:1018
int pad_idx
index of the filt_ctx pad to use for linking
Definition avfilter.h:1021
char * name
unique name for this input/output in the list
Definition avfilter.h:1015
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition avfilter.h:1024
Filter definition.
Definition avfilter.h:145
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:309
const char * name
Filter name.
Definition avfilter.h:149
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:247
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition avfilter.h:259
int flags
A combination of AVFILTER_FLAG_*.
Definition avfilter.h:188
int(* query_formats)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition avfilter.h:283
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition avfilter.h:211
int flags_internal
Additional flags for avfilter internal use only.
Definition avfilter.h:287
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition avfilter.h:183
int priv_size
size of private data to allocate for the filter
Definition avfilter.h:285
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition avfilter.h:234
const AVFilterPad * outputs
List of outputs, terminated by a zeroed element.
Definition avfilter.h:173
const AVFilterPad * inputs
List of inputs, terminated by a zeroed element.
Definition avfilter.h:165
int(* init_opaque)(AVFilterContext *ctx, void *opaque)
Filter initialization function, alternative to the init() callback.
Definition avfilter.h:316
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition avfilter.h:330
const char * description
A description of the filter.
Definition avfilter.h:156
This structure describes decoded (raw) audio or video data.
Definition frame.h:318
Rational number (pair of numerator and denominator).
Definition rational.h:58