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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 
40 #include "libavutil/attributes.h"
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  */
55 unsigned avfilter_version(void);
56 
57 /**
58  * Return the libavfilter build-time configuration.
59  */
60 const char *avfilter_configuration(void);
61 
62 /**
63  * Return the libavfilter license.
64  */
65 const char *avfilter_license(void);
66 
67 typedef struct AVFilterContext AVFilterContext;
68 typedef struct AVFilterLink AVFilterLink;
69 typedef struct AVFilterPad AVFilterPad;
70 typedef struct AVFilterFormats AVFilterFormats;
71 
72 /**
73  * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
74  * AVFilter.inputs/outputs).
75  */
76 int avfilter_pad_count(const AVFilterPad *pads);
77 
78 /**
79  * Get the name of an AVFilterPad.
80  *
81  * @param pads an array of AVFilterPads
82  * @param pad_idx index of the pad in the array it; is the caller's
83  * responsibility to ensure the index is valid
84  *
85  * @return name of the pad_idx'th pad in pads
86  */
87 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
88 
89 /**
90  * Get the type 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 type of the pad_idx'th pad in pads
97  */
98 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
99 
100 /**
101  * The number of the filter inputs is not determined just by AVFilter.inputs.
102  * The filter might add additional inputs during initialization depending on the
103  * options supplied to it.
104  */
105 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
106 /**
107  * The number of the filter outputs is not determined just by AVFilter.outputs.
108  * The filter might add additional outputs during initialization depending on
109  * the options supplied to it.
110  */
111 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
112 /**
113  * The filter supports multithreading by splitting frames into multiple parts
114  * and processing them concurrently.
115  */
116 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
117 /**
118  * Some filters support a generic "enable" expression option that can be used
119  * to enable or disable a filter in the timeline. Filters supporting this
120  * option have this flag set. When the enable expression is false, the default
121  * no-op filter_frame() function is called in place of the filter_frame()
122  * callback defined on each input pad, thus the frame is passed unchanged to
123  * the next filters.
124  */
125 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
126 /**
127  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
128  * have its filter_frame() callback(s) called as usual even when the enable
129  * expression is false. The filter will disable filtering within the
130  * filter_frame() callback(s) itself, for example executing code depending on
131  * the AVFilterContext->is_disabled value.
132  */
133 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
134 /**
135  * Handy mask to test whether the filter supports or no the timeline feature
136  * (internally or generically).
137  */
138 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
139 
140 /**
141  * Filter definition. This defines the pads a filter contains, and all the
142  * callback functions used to interact with the filter.
143  */
144 typedef struct AVFilter {
145  /**
146  * Filter name. Must be non-NULL and unique among filters.
147  */
148  const char *name;
149 
150  /**
151  * A description of the filter. May be NULL.
152  *
153  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
154  */
155  const char *description;
156 
157  /**
158  * List of inputs, terminated by a zeroed element.
159  *
160  * NULL if there are no (static) inputs. Instances of filters with
161  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
162  * this list.
163  */
165  /**
166  * List of outputs, terminated by a zeroed element.
167  *
168  * NULL if there are no (static) outputs. Instances of filters with
169  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
170  * this list.
171  */
173 
174  /**
175  * A class for the private data, used to declare filter private AVOptions.
176  * This field is NULL for filters that do not declare any options.
177  *
178  * If this field is non-NULL, the first member of the filter private data
179  * must be a pointer to AVClass, which will be set by libavfilter generic
180  * code to this class.
181  */
183 
184  /**
185  * A combination of AVFILTER_FLAG_*
186  */
187  int flags;
188 
189  /*****************************************************************
190  * All fields below this line are not part of the public API. They
191  * may not be used outside of libavfilter and can be changed and
192  * removed at will.
193  * New public fields should be added right above.
194  *****************************************************************
195  */
196 
197  /**
198  * Filter pre-initialization function
199  *
200  * This callback will be called immediately after the filter context is
201  * allocated, to allow allocating and initing sub-objects.
202  *
203  * If this callback is not NULL, the uninit callback will be called on
204  * allocation failure.
205  *
206  * @return 0 on success,
207  * AVERROR code on failure (but the code will be
208  * dropped and treated as ENOMEM by the calling code)
209  */
211 
212  /**
213  * Filter initialization function.
214  *
215  * This callback will be called only once during the filter lifetime, after
216  * all the options have been set, but before links between filters are
217  * established and format negotiation is done.
218  *
219  * Basic filter initialization should be done here. Filters with dynamic
220  * inputs and/or outputs should create those inputs/outputs here based on
221  * provided options. No more changes to this filter's inputs/outputs can be
222  * done after this callback.
223  *
224  * This callback must not assume that the filter links exist or frame
225  * parameters are known.
226  *
227  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
228  * initialization fails, so this callback does not have to clean up on
229  * failure.
230  *
231  * @return 0 on success, a negative AVERROR on failure
232  */
234 
235  /**
236  * Should be set instead of @ref AVFilter.init "init" by the filters that
237  * want to pass a dictionary of AVOptions to nested contexts that are
238  * allocated during init.
239  *
240  * On return, the options dict should be freed and replaced with one that
241  * contains all the options which could not be processed by this filter (or
242  * with NULL if all the options were processed).
243  *
244  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
245  */
247 
248  /**
249  * Filter uninitialization function.
250  *
251  * Called only once right before the filter is freed. Should deallocate any
252  * memory held by the filter, release any buffer references, etc. It does
253  * not need to deallocate the AVFilterContext.priv memory itself.
254  *
255  * This callback may be called even if @ref AVFilter.init "init" was not
256  * called or failed, so it must be prepared to handle such a situation.
257  */
259 
260  /**
261  * Query formats supported by the filter on its inputs and outputs.
262  *
263  * This callback is called after the filter is initialized (so the inputs
264  * and outputs are fixed), shortly before the format negotiation. This
265  * callback may be called more than once.
266  *
267  * This callback must set AVFilterLink.out_formats on every input link and
268  * AVFilterLink.in_formats on every output link to a list of pixel/sample
269  * formats that the filter supports on that link. For audio links, this
270  * filter must also set @ref AVFilterLink.in_samplerates "in_samplerates" /
271  * @ref AVFilterLink.out_samplerates "out_samplerates" and
272  * @ref AVFilterLink.in_channel_layouts "in_channel_layouts" /
273  * @ref AVFilterLink.out_channel_layouts "out_channel_layouts" analogously.
274  *
275  * This callback may be NULL for filters with one input, in which case
276  * libavfilter assumes that it supports all input formats and preserves
277  * them on output.
278  *
279  * @return zero on success, a negative value corresponding to an
280  * AVERROR code otherwise
281  */
283 
284  int priv_size; ///< size of private data to allocate for the filter
285 
286  int flags_internal; ///< Additional flags for avfilter internal use only.
287 
288  /**
289  * Used by the filter registration system. Must not be touched by any other
290  * code.
291  */
292  struct AVFilter *next;
293 
294  /**
295  * Make the filter instance process a command.
296  *
297  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
298  * @param arg the argument for the command
299  * @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.
300  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
301  * time consuming then a filter should treat it like an unsupported command
302  *
303  * @returns >=0 on success otherwise an error code.
304  * AVERROR(ENOSYS) on unsupported commands
305  */
306  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
307 
308  /**
309  * Filter initialization function, alternative to the init()
310  * callback. Args contains the user-supplied parameters, opaque is
311  * used for providing binary data.
312  */
313  int (*init_opaque)(AVFilterContext *ctx, void *opaque);
314 
315  /**
316  * Filter activation function.
317  *
318  * Called when any processing is needed from the filter, instead of any
319  * filter_frame and request_frame on pads.
320  *
321  * The function must examine inlinks and outlinks and perform a single
322  * step of processing. If there is nothing to do, the function must do
323  * nothing and not return an error. If more steps are or may be
324  * possible, it must use ff_filter_set_ready() to schedule another
325  * activation.
326  */
328 } AVFilter;
329 
330 /**
331  * Process multiple parts of the frame concurrently.
332  */
333 #define AVFILTER_THREAD_SLICE (1 << 0)
334 
335 typedef struct AVFilterInternal AVFilterInternal;
336 
337 /** An instance of a filter */
339  const AVClass *av_class; ///< needed for av_log() and filters common options
340 
341  const AVFilter *filter; ///< the AVFilter of which this is an instance
342 
343  char *name; ///< name of this filter instance
344 
345  AVFilterPad *input_pads; ///< array of input pads
346  AVFilterLink **inputs; ///< array of pointers to input links
347  unsigned nb_inputs; ///< number of input pads
348 
349  AVFilterPad *output_pads; ///< array of output pads
350  AVFilterLink **outputs; ///< array of pointers to output links
351  unsigned nb_outputs; ///< number of output pads
352 
353  void *priv; ///< private data for use by the filter
354 
355  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
356 
357  /**
358  * Type of multithreading being allowed/used. A combination of
359  * AVFILTER_THREAD_* flags.
360  *
361  * May be set by the caller before initializing the filter to forbid some
362  * or all kinds of multithreading for this filter. The default is allowing
363  * everything.
364  *
365  * When the filter is initialized, this field is combined using bit AND with
366  * AVFilterGraph.thread_type to get the final mask used for determining
367  * allowed threading types. I.e. a threading type needs to be set in both
368  * to be allowed.
369  *
370  * After the filter is initialized, libavfilter sets this field to the
371  * threading type that is actually used (0 for no multithreading).
372  */
374 
375  /**
376  * An opaque struct for libavfilter internal use.
377  */
378  AVFilterInternal *internal;
379 
381 
382  char *enable_str; ///< enable expression string
383  void *enable; ///< parsed expression (AVExpr*)
384  double *var_values; ///< variable values for the enable expression
385  int is_disabled; ///< the enabled state from the last expression evaluation
386 
387  /**
388  * For filters which will create hardware frames, sets the device the
389  * filter should create them in. All other filters will ignore this field:
390  * in particular, a filter which consumes or processes hardware frames will
391  * instead use the hw_frames_ctx field in AVFilterLink to carry the
392  * hardware context information.
393  */
395 
396  /**
397  * Max number of threads allowed in this filter instance.
398  * If <= 0, its value is ignored.
399  * Overrides global number of threads set per filter graph.
400  */
402 
403  /**
404  * Ready status of the filter.
405  * A non-0 value means that the filter needs activating;
406  * a higher value suggests a more urgent activation.
407  */
408  unsigned ready;
409 };
410 
411 /**
412  * A link between two filters. This contains pointers to the source and
413  * destination filters between which this link exists, and the indexes of
414  * the pads involved. In addition, this link also contains the parameters
415  * which have been negotiated and agreed upon between the filter, such as
416  * image dimensions, format, etc.
417  *
418  * Applications must not normally access the link structure directly.
419  * Use the buffersrc and buffersink API instead.
420  * In the future, access to the header may be reserved for filters
421  * implementation.
422  */
423 struct AVFilterLink {
424  AVFilterContext *src; ///< source filter
425  AVFilterPad *srcpad; ///< output pad on the source filter
426 
427  AVFilterContext *dst; ///< dest filter
428  AVFilterPad *dstpad; ///< input pad on the dest filter
429 
430  enum AVMediaType type; ///< filter media type
431 
432  /* These parameters apply only to video */
433  int w; ///< agreed upon image width
434  int h; ///< agreed upon image height
435  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
436  /* These parameters apply only to audio */
437  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
438  int sample_rate; ///< samples per second
439 
440  int format; ///< agreed upon media format
441 
442  /**
443  * Define the time base used by the PTS of the frames/samples
444  * which will pass through this link.
445  * During the configuration stage, each filter is supposed to
446  * change only the output timebase, while the timebase of the
447  * input link is assumed to be an unchangeable property.
448  */
450 
451  /*****************************************************************
452  * All fields below this line are not part of the public API. They
453  * may not be used outside of libavfilter and can be changed and
454  * removed at will.
455  * New public fields should be added right above.
456  *****************************************************************
457  */
458  /**
459  * Lists of formats and channel layouts supported by the input and output
460  * filters respectively. These lists are used for negotiating the format
461  * to actually be used, which will be loaded into the format and
462  * channel_layout members, above, when chosen.
463  *
464  */
467 
468  /**
469  * Lists of channel layouts and sample rates used for automatic
470  * negotiation.
471  */
476 
477  /**
478  * Audio only, the destination filter sets this to a non-zero value to
479  * request that buffers with the given number of samples should be sent to
480  * it. AVFilterPad.needs_fifo must also be set on the corresponding input
481  * pad.
482  * Last buffer before EOF will be padded with silence.
483  */
485 
486  /** stage of the initialization of the link properties (dimensions, etc) */
487  enum {
488  AVLINK_UNINIT = 0, ///< not started
489  AVLINK_STARTINIT, ///< started, but incomplete
490  AVLINK_INIT ///< complete
491  } init_state;
492 
493  /**
494  * Graph the filter belongs to.
495  */
497 
498  /**
499  * Current timestamp of the link, as defined by the most recent
500  * frame(s), in link time_base units.
501  */
502  int64_t current_pts;
503 
504  /**
505  * Current timestamp of the link, as defined by the most recent
506  * frame(s), in AV_TIME_BASE units.
507  */
508  int64_t current_pts_us;
509 
510  /**
511  * Index in the age array.
512  */
514 
515  /**
516  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
517  * if left to 0/0, will be automatically copied from the first input
518  * of the source filter if it exists.
519  *
520  * Sources should set it to the best estimation of the real frame rate.
521  * If the source frame rate is unknown or variable, set this to 1/0.
522  * Filters should update it if necessary depending on their function.
523  * Sinks can use it to set a default output frame rate.
524  * It is similar to the r_frame_rate field in AVStream.
525  */
527 
528  /**
529  * Buffer partially filled with samples to achieve a fixed/minimum size.
530  */
532 
533  /**
534  * Size of the partial buffer to allocate.
535  * Must be between min_samples and max_samples.
536  */
538 
539  /**
540  * Minimum number of samples to filter at once. If filter_frame() is
541  * called with fewer samples, it will accumulate them in partial_buf.
542  * This field and the related ones must not be changed after filtering
543  * has started.
544  * If 0, all related fields are ignored.
545  */
547 
548  /**
549  * Maximum number of samples to filter at once. If filter_frame() is
550  * called with more samples, it will split them.
551  */
553 
554  /**
555  * Number of channels.
556  */
557  int channels;
558 
559  /**
560  * Link processing flags.
561  */
562  unsigned flags;
563 
564  /**
565  * Number of past frames sent through the link.
566  */
568 
569  /**
570  * A pointer to a FFFramePool struct.
571  */
572  void *frame_pool;
573 
574  /**
575  * True if a frame is currently wanted on the output of this filter.
576  * Set when ff_request_frame() is called by the output,
577  * cleared when a frame is filtered.
578  */
580 
581  /**
582  * For hwaccel pixel formats, this should be a reference to the
583  * AVHWFramesContext describing the frames.
584  */
586 
587 #ifndef FF_INTERNAL_FIELDS
588 
589  /**
590  * Internal structure members.
591  * The fields below this limit are internal for libavfilter's use
592  * and must in no way be accessed by applications.
593  */
594  char reserved[0xF000];
595 
596 #else /* FF_INTERNAL_FIELDS */
597 
598  /**
599  * Queue of frames waiting to be filtered.
600  */
601  FFFrameQueue fifo;
602 
603  /**
604  * If set, the source filter can not generate a frame as is.
605  * The goal is to avoid repeatedly calling the request_frame() method on
606  * the same link.
607  */
608  int frame_blocked_in;
609 
610  /**
611  * Link input status.
612  * If not zero, all attempts of filter_frame will fail with the
613  * corresponding code.
614  */
615  int status_in;
616 
617  /**
618  * Timestamp of the input status change.
619  */
620  int64_t status_in_pts;
621 
622  /**
623  * Link output status.
624  * If not zero, all attempts of request_frame will fail with the
625  * corresponding code.
626  */
627  int status_out;
628 
629 #endif /* FF_INTERNAL_FIELDS */
630 
631 };
632 
633 /**
634  * Link two filters together.
635  *
636  * @param src the source filter
637  * @param srcpad index of the output pad on the source filter
638  * @param dst the destination filter
639  * @param dstpad index of the input pad on the destination filter
640  * @return zero on success
641  */
642 int avfilter_link(AVFilterContext *src, unsigned srcpad,
643  AVFilterContext *dst, unsigned dstpad);
644 
645 /**
646  * Free the link in *link, and set its pointer to NULL.
647  */
648 void avfilter_link_free(AVFilterLink **link);
649 
650 #if FF_API_FILTER_GET_SET
651 /**
652  * Get the number of channels of a link.
653  * @deprecated Use av_buffersink_get_channels()
654  */
656 int avfilter_link_get_channels(AVFilterLink *link);
657 #endif
658 
659 /**
660  * Set the closed field of a link.
661  * @deprecated applications are not supposed to mess with links, they should
662  * close the sinks.
663  */
665 void avfilter_link_set_closed(AVFilterLink *link, int closed);
666 
667 /**
668  * Negotiate the media format, dimensions, etc of all inputs to a filter.
669  *
670  * @param filter the filter to negotiate the properties for its inputs
671  * @return zero on successful negotiation
672  */
674 
675 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
676 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
677 
678 /**
679  * Make the filter instance process a command.
680  * It is recommended to use avfilter_graph_send_command().
681  */
682 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
683 
684 /** Initialize the filter system. Register all builtin filters. */
685 void avfilter_register_all(void);
686 
687 /**
688  * Register a filter. This is only needed if you plan to use
689  * avfilter_get_by_name later to lookup the AVFilter structure by name. A
690  * filter can still by instantiated with avfilter_graph_alloc_filter even if it
691  * is not registered.
692  *
693  * @param filter the filter to register
694  * @return 0 if the registration was successful, a negative value
695  * otherwise
696  */
698 
699 /**
700  * Get a filter definition matching the given name.
701  *
702  * @param name the filter name to find
703  * @return the filter definition, if any matching one is registered.
704  * NULL if none found.
705  */
706 const AVFilter *avfilter_get_by_name(const char *name);
707 
708 /**
709  * Iterate over all registered filters.
710  * @return If prev is non-NULL, next registered filter after prev or NULL if
711  * prev is the last filter. If prev is NULL, return the first registered filter.
712  */
713 const AVFilter *avfilter_next(const AVFilter *prev);
714 
715 /**
716  * Initialize a filter with the supplied parameters.
717  *
718  * @param ctx uninitialized filter context to initialize
719  * @param args Options to initialize the filter with. This must be a
720  * ':'-separated list of options in the 'key=value' form.
721  * May be NULL if the options have been set directly using the
722  * AVOptions API or there are no options that need to be set.
723  * @return 0 on success, a negative AVERROR on failure
724  */
725 int avfilter_init_str(AVFilterContext *ctx, const char *args);
726 
727 /**
728  * Initialize a filter with the supplied dictionary of options.
729  *
730  * @param ctx uninitialized filter context to initialize
731  * @param options An AVDictionary filled with options for this filter. On
732  * return this parameter will be destroyed and replaced with
733  * a dict containing options that were not found. This dictionary
734  * must be freed by the caller.
735  * May be NULL, then this function is equivalent to
736  * avfilter_init_str() with the second parameter set to NULL.
737  * @return 0 on success, a negative AVERROR on failure
738  *
739  * @note This function and avfilter_init_str() do essentially the same thing,
740  * the difference is in manner in which the options are passed. It is up to the
741  * calling code to choose whichever is more preferable. The two functions also
742  * behave differently when some of the provided options are not declared as
743  * supported by the filter. In such a case, avfilter_init_str() will fail, but
744  * this function will leave those extra options in the options AVDictionary and
745  * continue as usual.
746  */
748 
749 /**
750  * Free a filter context. This will also remove the filter from its
751  * filtergraph's list of filters.
752  *
753  * @param filter the filter to free
754  */
756 
757 /**
758  * Insert a filter in the middle of an existing link.
759  *
760  * @param link the link into which the filter should be inserted
761  * @param filt the filter to be inserted
762  * @param filt_srcpad_idx the input pad on the filter to connect
763  * @param filt_dstpad_idx the output pad on the filter to connect
764  * @return zero on success
765  */
767  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
768 
769 /**
770  * @return AVClass for AVFilterContext.
771  *
772  * @see av_opt_find().
773  */
774 const AVClass *avfilter_get_class(void);
775 
777 
778 /**
779  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
780  * executed multiple times, possibly in parallel.
781  *
782  * @param ctx the filter context the job belongs to
783  * @param arg an opaque parameter passed through from @ref
784  * AVFilterGraph.execute
785  * @param jobnr the index of the job being executed
786  * @param nb_jobs the total number of jobs
787  *
788  * @return 0 on success, a negative AVERROR on error
789  */
790 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
791 
792 /**
793  * A function executing multiple jobs, possibly in parallel.
794  *
795  * @param ctx the filter context to which the jobs belong
796  * @param func the function to be called multiple times
797  * @param arg the argument to be passed to func
798  * @param ret a nb_jobs-sized array to be filled with return values from each
799  * invocation of func
800  * @param nb_jobs the number of jobs to execute
801  *
802  * @return 0 on success, a negative AVERROR on error
803  */
805  void *arg, int *ret, int nb_jobs);
806 
807 typedef struct AVFilterGraph {
810  unsigned nb_filters;
811 
812  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
813 #if FF_API_LAVR_OPTS
814  attribute_deprecated char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters
815 #endif
816 
817  /**
818  * Type of multithreading allowed for filters in this graph. A combination
819  * of AVFILTER_THREAD_* flags.
820  *
821  * May be set by the caller at any point, the setting will apply to all
822  * filters initialized after that. The default is allowing everything.
823  *
824  * When a filter in this graph is initialized, this field is combined using
825  * bit AND with AVFilterContext.thread_type to get the final mask used for
826  * determining allowed threading types. I.e. a threading type needs to be
827  * set in both to be allowed.
828  */
830 
831  /**
832  * Maximum number of threads used by filters in this graph. May be set by
833  * the caller before adding any filters to the filtergraph. Zero (the
834  * default) means that the number of threads is determined automatically.
835  */
837 
838  /**
839  * Opaque object for libavfilter internal use.
840  */
842 
843  /**
844  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
845  * be used from callbacks like @ref AVFilterGraph.execute.
846  * Libavfilter will not touch this field in any way.
847  */
848  void *opaque;
849 
850  /**
851  * This callback may be set by the caller immediately after allocating the
852  * graph and before adding any filters to it, to provide a custom
853  * multithreading implementation.
854  *
855  * If set, filters with slice threading capability will call this callback
856  * to execute multiple jobs in parallel.
857  *
858  * If this field is left unset, libavfilter will use its internal
859  * implementation, which may or may not be multithreaded depending on the
860  * platform and build options.
861  */
863 
864  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
865 
866  /**
867  * Private fields
868  *
869  * The following fields are for internal use only.
870  * Their type, offset, number and semantic can change without notice.
871  */
872 
875 
877 } AVFilterGraph;
878 
879 /**
880  * Allocate a filter graph.
881  *
882  * @return the allocated filter graph on success or NULL.
883  */
885 
886 /**
887  * Create a new filter instance in a filter graph.
888  *
889  * @param graph graph in which the new filter will be used
890  * @param filter the filter to create an instance of
891  * @param name Name to give to the new instance (will be copied to
892  * AVFilterContext.name). This may be used by the caller to identify
893  * different filters, libavfilter itself assigns no semantics to
894  * this parameter. May be NULL.
895  *
896  * @return the context of the newly created filter instance (note that it is
897  * also retrievable directly through AVFilterGraph.filters or with
898  * avfilter_graph_get_filter()) on success or NULL on failure.
899  */
901  const AVFilter *filter,
902  const char *name);
903 
904 /**
905  * Get a filter instance identified by instance name from graph.
906  *
907  * @param graph filter graph to search through.
908  * @param name filter instance name (should be unique in the graph).
909  * @return the pointer to the found filter instance or NULL if it
910  * cannot be found.
911  */
913 
914 /**
915  * Create and add a filter instance into an existing graph.
916  * The filter instance is created from the filter filt and inited
917  * with the parameters args and opaque.
918  *
919  * In case of success put in *filt_ctx the pointer to the created
920  * filter instance, otherwise set *filt_ctx to NULL.
921  *
922  * @param name the instance name to give to the created filter instance
923  * @param graph_ctx the filter graph
924  * @return a negative AVERROR error code in case of failure, a non
925  * negative value otherwise
926  */
928  const char *name, const char *args, void *opaque,
929  AVFilterGraph *graph_ctx);
930 
931 /**
932  * Enable or disable automatic format conversion inside the graph.
933  *
934  * Note that format conversion can still happen inside explicitly inserted
935  * scale and aresample filters.
936  *
937  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
938  */
940 
941 enum {
942  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
943  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
944 };
945 
946 /**
947  * Check validity and configure all the links and formats in the graph.
948  *
949  * @param graphctx the filter graph
950  * @param log_ctx context used for logging
951  * @return >= 0 in case of success, a negative AVERROR code otherwise
952  */
953 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
954 
955 /**
956  * Free a graph, destroy its links, and set *graph to NULL.
957  * If *graph is NULL, do nothing.
958  */
959 void avfilter_graph_free(AVFilterGraph **graph);
960 
961 /**
962  * A linked-list of the inputs/outputs of the filter chain.
963  *
964  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
965  * where it is used to communicate open (unlinked) inputs and outputs from and
966  * to the caller.
967  * This struct specifies, per each not connected pad contained in the graph, the
968  * filter context and the pad index required for establishing a link.
969  */
970 typedef struct AVFilterInOut {
971  /** unique name for this input/output in the list */
972  char *name;
973 
974  /** filter context associated to this input/output */
976 
977  /** index of the filt_ctx pad to use for linking */
978  int pad_idx;
979 
980  /** next input/input in the list, NULL if this is the last */
982 } AVFilterInOut;
983 
984 /**
985  * Allocate a single AVFilterInOut entry.
986  * Must be freed with avfilter_inout_free().
987  * @return allocated AVFilterInOut on success, NULL on failure.
988  */
990 
991 /**
992  * Free the supplied list of AVFilterInOut and set *inout to NULL.
993  * If *inout is NULL, do nothing.
994  */
995 void avfilter_inout_free(AVFilterInOut **inout);
996 
997 /**
998  * Add a graph described by a string to a graph.
999  *
1000  * @note The caller must provide the lists of inputs and outputs,
1001  * which therefore must be known before calling the function.
1002  *
1003  * @note The inputs parameter describes inputs of the already existing
1004  * part of the graph; i.e. from the point of view of the newly created
1005  * part, they are outputs. Similarly the outputs parameter describes
1006  * outputs of the already existing filters, which are provided as
1007  * inputs to the parsed filters.
1008  *
1009  * @param graph the filter graph where to link the parsed graph context
1010  * @param filters string to be parsed
1011  * @param inputs linked list to the inputs of the graph
1012  * @param outputs linked list to the outputs of the graph
1013  * @return zero on success, a negative AVERROR code on error
1014  */
1015 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1017  void *log_ctx);
1018 
1019 /**
1020  * Add a graph described by a string to a graph.
1021  *
1022  * In the graph filters description, if the input label of the first
1023  * filter is not specified, "in" is assumed; if the output label of
1024  * the last filter is not specified, "out" is assumed.
1025  *
1026  * @param graph the filter graph where to link the parsed graph context
1027  * @param filters string to be parsed
1028  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1029  * If non-NULL, *inputs is updated to contain the list of open inputs
1030  * after the parsing, should be freed with avfilter_inout_free().
1031  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1032  * If non-NULL, *outputs is updated to contain the list of open outputs
1033  * after the parsing, should be freed with avfilter_inout_free().
1034  * @return non negative on success, a negative AVERROR code on error
1035  */
1036 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1038  void *log_ctx);
1039 
1040 /**
1041  * Add a graph described by a string to a graph.
1042  *
1043  * @param[in] graph the filter graph where to link the parsed graph context
1044  * @param[in] filters string to be parsed
1045  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1046  * parsed graph will be returned here. It is to be freed
1047  * by the caller using avfilter_inout_free().
1048  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1049  * parsed graph will be returned here. It is to be freed by the
1050  * caller using avfilter_inout_free().
1051  * @return zero on success, a negative AVERROR code on error
1052  *
1053  * @note This function returns the inputs and outputs that are left
1054  * unlinked after parsing the graph and the caller then deals with
1055  * them.
1056  * @note This function makes no reference whatsoever to already
1057  * existing parts of the graph and the inputs parameter will on return
1058  * contain inputs of the newly parsed part of the graph. Analogously
1059  * the outputs parameter will contain outputs of the newly created
1060  * filters.
1061  */
1062 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1065 
1066 /**
1067  * Send a command to one or more filter instances.
1068  *
1069  * @param graph the filter graph
1070  * @param target the filter(s) to which the command should be sent
1071  * "all" sends to all filters
1072  * otherwise it can be a filter or filter instance name
1073  * which will send the command to all matching filters.
1074  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1075  * @param arg the argument for the command
1076  * @param res a buffer with size res_size where the filter(s) can return a response.
1077  *
1078  * @returns >=0 on success otherwise an error code.
1079  * AVERROR(ENOSYS) on unsupported commands
1080  */
1081 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1082 
1083 /**
1084  * Queue a command for one or more filter instances.
1085  *
1086  * @param graph the filter graph
1087  * @param target the filter(s) to which the command should be sent
1088  * "all" sends to all filters
1089  * otherwise it can be a filter or filter instance name
1090  * which will send the command to all matching filters.
1091  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1092  * @param arg the argument for the command
1093  * @param ts time at which the command should be sent to the filter
1094  *
1095  * @note As this executes commands after this function returns, no return code
1096  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1097  */
1098 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1099 
1100 
1101 /**
1102  * Dump a graph into a human-readable string representation.
1103  *
1104  * @param graph the graph to dump
1105  * @param options formatting options; currently ignored
1106  * @return a string, or NULL in case of memory allocation failure;
1107  * the string must be freed using av_free
1108  */
1109 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1110 
1111 /**
1112  * Request a frame on the oldest sink link.
1113  *
1114  * If the request returns AVERROR_EOF, try the next.
1115  *
1116  * Note that this function is not meant to be the sole scheduling mechanism
1117  * of a filtergraph, only a convenience function to help drain a filtergraph
1118  * in a balanced way under normal circumstances.
1119  *
1120  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1121  * some of the sinks during the process.
1122  * When there are multiple sink links, in case the requested link
1123  * returns an EOF, this may cause a filter to flush pending frames
1124  * which are sent to another sink link, although unrequested.
1125  *
1126  * @return the return value of ff_request_frame(),
1127  * or AVERROR_EOF if all links returned AVERROR_EOF
1128  */
1130 
1131 /**
1132  * @}
1133  */
1134 
1135 #endif /* AVFILTER_AVFILTER_H */
AVFilterContext ** filters
Definition: avfilter.h:809
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
Enable or disable automatic format conversion inside the graph.
double * var_values
variable values for the enable expression
Definition: avfilter.h:384
int sink_links_count
Definition: avfilter.h:874
This structure describes decoded (raw) audio or video data.
Definition: frame.h:201
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.
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:829
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:802
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:83
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:233
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:210
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:203
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:981
Queue of AVFrame pointers.
Definition: framequeue.h:53
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
Definition: avfilter.c:1081
Libavfilter version macros.
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
AVBufferRef * hw_device_ctx
For filters which will create hardware frames, sets the device the filter should create them in...
Definition: avfilter.h:394
Convenience header that includes libavutil's core.
int(* query_formats)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:282
#define src
Definition: vp8dsp.c:254
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:373
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:385
Macro definitions for various function/variable attributes.
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:401
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:812
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:355
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:284
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
char * name
name of this filter instance
Definition: avfilter.h:343
Public dictionary API.
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:862
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:135
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:349
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, int clip)
Definition: cfhd.c:97
const char * avfilter_license(void)
Return the libavfilter license.
Definition: avfilter.c:88
unsigned ready
Ready status of the filter.
Definition: avfilter.h:408
all automatic conversions disabled
Definition: avfilter.h:943
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:187
void avfilter_register_all(void)
Initialize the filter system.
Definition: allfilters.c:422
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.
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:836
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:277
static int flags
Definition: log.c:55
const AVFilter * avfilter_next(const AVFilter *prev)
Iterate over all registered filters.
Definition: avfilter.c:618
AVFilterContext * avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
Get a filter instance identified by instance name from graph.
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:258
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:306
int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs)
Add a graph described by a string to a graph.
Definition: graphparser.c:407
A filter pad used for either input or output.
Definition: internal.h:54
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:345
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:790
const AVClass * av_class
Definition: avfilter.h:808
unsigned nb_outputs
number of output pads
Definition: avfilter.h:351
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
Definition: avfilter.c:77
void * priv
private data for use by the filter
Definition: avfilter.h:353
char * enable_str
enable expression string
Definition: avfilter.h:382
const char * arg
Definition: jacosubdec.c:66
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:246
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:873
reference-counted frame API
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: avfilter.c:581
attribute_deprecated void avfilter_link_set_closed(AVFilterLink *link, int closed)
Set the closed field of a link.
Definition: avfilter.c:235
unsigned nb_inputs
number of input pads
Definition: avfilter.h:347
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
AVFormatContext * ctx
Definition: movenc.c:48
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:286
int(* init_opaque)(AVFilterContext *ctx, void *opaque)
Filter initialization function, alternative to the init() callback.
Definition: avfilter.h:313
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:975
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
A list of supported channel layouts.
Definition: formats.h:85
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:966
const AVFilterPad * inputs
List of inputs, terminated by a zeroed element.
Definition: avfilter.h:164
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1662
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:970
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.
Definition: avfilter.c:240
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:804
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:182
all automatic conversions enabled
Definition: avfilter.h:942
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
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.
Definition: avfilter.c:557
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.
Definition: graphparser.c:475
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:978
Rational number (pair of numerator and denominator).
Definition: rational.h:58
struct AVFilter * next
Used by the filter registration system.
Definition: avfilter.h:292
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:67
AVMediaType
Definition: avutil.h:199
refcounted data buffer API
const char * name
Filter name.
Definition: avfilter.h:148
unsigned nb_filters
Definition: avfilter.h:810
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
Definition: avfilter.c:83
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
Definition: avfilter.c:1076
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
char * name
unique name for this input/output in the list
Definition: avfilter.h:972
static const int8_t filt[NUMTAPS]
Definition: af_earwax.c:39
#define attribute_deprecated
Definition: attributes.h:94
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:929
A reference to a data buffer.
Definition: buffer.h:81
void * opaque
Opaque user data.
Definition: avfilter.h:848
int
const OptionDef options[]
Definition: ffmpeg_opt.c:3291
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
Definition: graphparser.c:198
Utilties for rational number calculation.
struct AVFilterCommand * command_queue
Definition: avfilter.h:380
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:154
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.
char * aresample_swr_opts
swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions ...
Definition: avfilter.h:864
pixel format definitions
const char * description
A description of the filter.
Definition: avfilter.h:155
int avfilter_register(AVFilter *filter)
Register a filter.
Definition: avfilter.c:597
AVFilterContext * avfilter_graph_alloc_filter(AVFilterGraph *graph, const AVFilter *filter, const char *name)
Create a new filter instance in a filter graph.
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:383
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:339
static const struct PPFilter filters[]
Definition: postprocess.c:134
A list of supported formats for one end of a filter link.
Definition: formats.h:64
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.
Definition: graphparser.c:538
An instance of a filter.
Definition: avfilter.h:338
int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
Definition: avfilter.c:623
const AVFilterPad * outputs
List of outputs, terminated by a zeroed element.
Definition: avfilter.h:172
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:327
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
Definition: avfilter.c:174
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:341
unsigned disable_auto_convert
Definition: avfilter.h:876
const char * name
Definition: opengl_enc.c:103