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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 initialization function.
199  *
200  * This callback will be called only once during the filter lifetime, after
201  * all the options have been set, but before links between filters are
202  * established and format negotiation is done.
203  *
204  * Basic filter initialization should be done here. Filters with dynamic
205  * inputs and/or outputs should create those inputs/outputs here based on
206  * provided options. No more changes to this filter's inputs/outputs can be
207  * done after this callback.
208  *
209  * This callback must not assume that the filter links exist or frame
210  * parameters are known.
211  *
212  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
213  * initialization fails, so this callback does not have to clean up on
214  * failure.
215  *
216  * @return 0 on success, a negative AVERROR on failure
217  */
219 
220  /**
221  * Should be set instead of @ref AVFilter.init "init" by the filters that
222  * want to pass a dictionary of AVOptions to nested contexts that are
223  * allocated during init.
224  *
225  * On return, the options dict should be freed and replaced with one that
226  * contains all the options which could not be processed by this filter (or
227  * with NULL if all the options were processed).
228  *
229  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
230  */
232 
233  /**
234  * Filter uninitialization function.
235  *
236  * Called only once right before the filter is freed. Should deallocate any
237  * memory held by the filter, release any buffer references, etc. It does
238  * not need to deallocate the AVFilterContext.priv memory itself.
239  *
240  * This callback may be called even if @ref AVFilter.init "init" was not
241  * called or failed, so it must be prepared to handle such a situation.
242  */
244 
245  /**
246  * Query formats supported by the filter on its inputs and outputs.
247  *
248  * This callback is called after the filter is initialized (so the inputs
249  * and outputs are fixed), shortly before the format negotiation. This
250  * callback may be called more than once.
251  *
252  * This callback must set AVFilterLink.out_formats on every input link and
253  * AVFilterLink.in_formats on every output link to a list of pixel/sample
254  * formats that the filter supports on that link. For audio links, this
255  * filter must also set @ref AVFilterLink.in_samplerates "in_samplerates" /
256  * @ref AVFilterLink.out_samplerates "out_samplerates" and
257  * @ref AVFilterLink.in_channel_layouts "in_channel_layouts" /
258  * @ref AVFilterLink.out_channel_layouts "out_channel_layouts" analogously.
259  *
260  * This callback may be NULL for filters with one input, in which case
261  * libavfilter assumes that it supports all input formats and preserves
262  * them on output.
263  *
264  * @return zero on success, a negative value corresponding to an
265  * AVERROR code otherwise
266  */
268 
269  int priv_size; ///< size of private data to allocate for the filter
270 
271  int flags_internal; ///< Additional flags for avfilter internal use only.
272 
273  /**
274  * Used by the filter registration system. Must not be touched by any other
275  * code.
276  */
277  struct AVFilter *next;
278 
279  /**
280  * Make the filter instance process a command.
281  *
282  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
283  * @param arg the argument for the command
284  * @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.
285  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
286  * time consuming then a filter should treat it like an unsupported command
287  *
288  * @returns >=0 on success otherwise an error code.
289  * AVERROR(ENOSYS) on unsupported commands
290  */
291  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
292 
293  /**
294  * Filter initialization function, alternative to the init()
295  * callback. Args contains the user-supplied parameters, opaque is
296  * used for providing binary data.
297  */
298  int (*init_opaque)(AVFilterContext *ctx, void *opaque);
299 
300  /**
301  * Filter activation function.
302  *
303  * Called when any processing is needed from the filter, instead of any
304  * filter_frame and request_frame on pads.
305  *
306  * The function must examine inlinks and outlinks and perform a single
307  * step of processing. If there is nothing to do, the function must do
308  * nothing and not return an error. If more steps are or may be
309  * possible, it must use ff_filter_set_ready() to schedule another
310  * activation.
311  */
313 } AVFilter;
314 
315 /**
316  * Process multiple parts of the frame concurrently.
317  */
318 #define AVFILTER_THREAD_SLICE (1 << 0)
319 
320 typedef struct AVFilterInternal AVFilterInternal;
321 
322 /** An instance of a filter */
324  const AVClass *av_class; ///< needed for av_log() and filters common options
325 
326  const AVFilter *filter; ///< the AVFilter of which this is an instance
327 
328  char *name; ///< name of this filter instance
329 
330  AVFilterPad *input_pads; ///< array of input pads
331  AVFilterLink **inputs; ///< array of pointers to input links
332  unsigned nb_inputs; ///< number of input pads
333 
334  AVFilterPad *output_pads; ///< array of output pads
335  AVFilterLink **outputs; ///< array of pointers to output links
336  unsigned nb_outputs; ///< number of output pads
337 
338  void *priv; ///< private data for use by the filter
339 
340  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
341 
342  /**
343  * Type of multithreading being allowed/used. A combination of
344  * AVFILTER_THREAD_* flags.
345  *
346  * May be set by the caller before initializing the filter to forbid some
347  * or all kinds of multithreading for this filter. The default is allowing
348  * everything.
349  *
350  * When the filter is initialized, this field is combined using bit AND with
351  * AVFilterGraph.thread_type to get the final mask used for determining
352  * allowed threading types. I.e. a threading type needs to be set in both
353  * to be allowed.
354  *
355  * After the filter is initialized, libavfilter sets this field to the
356  * threading type that is actually used (0 for no multithreading).
357  */
359 
360  /**
361  * An opaque struct for libavfilter internal use.
362  */
363  AVFilterInternal *internal;
364 
366 
367  char *enable_str; ///< enable expression string
368  void *enable; ///< parsed expression (AVExpr*)
369  double *var_values; ///< variable values for the enable expression
370  int is_disabled; ///< the enabled state from the last expression evaluation
371 
372  /**
373  * For filters which will create hardware frames, sets the device the
374  * filter should create them in. All other filters will ignore this field:
375  * in particular, a filter which consumes or processes hardware frames will
376  * instead use the hw_frames_ctx field in AVFilterLink to carry the
377  * hardware context information.
378  */
380 
381  /**
382  * Max number of threads allowed in this filter instance.
383  * If <= 0, its value is ignored.
384  * Overrides global number of threads set per filter graph.
385  */
387 
388  /**
389  * Ready status of the filter.
390  * A non-0 value means that the filter needs activating;
391  * a higher value suggests a more urgent activation.
392  */
393  unsigned ready;
394 };
395 
396 /**
397  * A link between two filters. This contains pointers to the source and
398  * destination filters between which this link exists, and the indexes of
399  * the pads involved. In addition, this link also contains the parameters
400  * which have been negotiated and agreed upon between the filter, such as
401  * image dimensions, format, etc.
402  *
403  * Applications must not normally access the link structure directly.
404  * Use the buffersrc and buffersink API instead.
405  * In the future, access to the header may be reserved for filters
406  * implementation.
407  */
408 struct AVFilterLink {
409  AVFilterContext *src; ///< source filter
410  AVFilterPad *srcpad; ///< output pad on the source filter
411 
412  AVFilterContext *dst; ///< dest filter
413  AVFilterPad *dstpad; ///< input pad on the dest filter
414 
415  enum AVMediaType type; ///< filter media type
416 
417  /* These parameters apply only to video */
418  int w; ///< agreed upon image width
419  int h; ///< agreed upon image height
420  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
421  /* These parameters apply only to audio */
422  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
423  int sample_rate; ///< samples per second
424 
425  int format; ///< agreed upon media format
426 
427  /**
428  * Define the time base used by the PTS of the frames/samples
429  * which will pass through this link.
430  * During the configuration stage, each filter is supposed to
431  * change only the output timebase, while the timebase of the
432  * input link is assumed to be an unchangeable property.
433  */
435 
436  /*****************************************************************
437  * All fields below this line are not part of the public API. They
438  * may not be used outside of libavfilter and can be changed and
439  * removed at will.
440  * New public fields should be added right above.
441  *****************************************************************
442  */
443  /**
444  * Lists of formats and channel layouts supported by the input and output
445  * filters respectively. These lists are used for negotiating the format
446  * to actually be used, which will be loaded into the format and
447  * channel_layout members, above, when chosen.
448  *
449  */
452 
453  /**
454  * Lists of channel layouts and sample rates used for automatic
455  * negotiation.
456  */
461 
462  /**
463  * Audio only, the destination filter sets this to a non-zero value to
464  * request that buffers with the given number of samples should be sent to
465  * it. AVFilterPad.needs_fifo must also be set on the corresponding input
466  * pad.
467  * Last buffer before EOF will be padded with silence.
468  */
470 
471  /** stage of the initialization of the link properties (dimensions, etc) */
472  enum {
473  AVLINK_UNINIT = 0, ///< not started
474  AVLINK_STARTINIT, ///< started, but incomplete
475  AVLINK_INIT ///< complete
476  } init_state;
477 
478  /**
479  * Graph the filter belongs to.
480  */
482 
483  /**
484  * Current timestamp of the link, as defined by the most recent
485  * frame(s), in link time_base units.
486  */
487  int64_t current_pts;
488 
489  /**
490  * Current timestamp of the link, as defined by the most recent
491  * frame(s), in AV_TIME_BASE units.
492  */
493  int64_t current_pts_us;
494 
495  /**
496  * Index in the age array.
497  */
499 
500  /**
501  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
502  * if left to 0/0, will be automatically copied from the first input
503  * of the source filter if it exists.
504  *
505  * Sources should set it to the best estimation of the real frame rate.
506  * If the source frame rate is unknown or variable, set this to 1/0.
507  * Filters should update it if necessary depending on their function.
508  * Sinks can use it to set a default output frame rate.
509  * It is similar to the r_frame_rate field in AVStream.
510  */
512 
513  /**
514  * Buffer partially filled with samples to achieve a fixed/minimum size.
515  */
517 
518  /**
519  * Size of the partial buffer to allocate.
520  * Must be between min_samples and max_samples.
521  */
523 
524  /**
525  * Minimum number of samples to filter at once. If filter_frame() is
526  * called with fewer samples, it will accumulate them in partial_buf.
527  * This field and the related ones must not be changed after filtering
528  * has started.
529  * If 0, all related fields are ignored.
530  */
532 
533  /**
534  * Maximum number of samples to filter at once. If filter_frame() is
535  * called with more samples, it will split them.
536  */
538 
539  /**
540  * Number of channels.
541  */
542  int channels;
543 
544  /**
545  * Link processing flags.
546  */
547  unsigned flags;
548 
549  /**
550  * Number of past frames sent through the link.
551  */
553 
554  /**
555  * A pointer to a FFFramePool struct.
556  */
557  void *frame_pool;
558 
559  /**
560  * True if a frame is currently wanted on the output of this filter.
561  * Set when ff_request_frame() is called by the output,
562  * cleared when a frame is filtered.
563  */
565 
566  /**
567  * For hwaccel pixel formats, this should be a reference to the
568  * AVHWFramesContext describing the frames.
569  */
571 
572 #ifndef FF_INTERNAL_FIELDS
573 
574  /**
575  * Internal structure members.
576  * The fields below this limit are internal for libavfilter's use
577  * and must in no way be accessed by applications.
578  */
579  char reserved[0xF000];
580 
581 #else /* FF_INTERNAL_FIELDS */
582 
583  /**
584  * Queue of frames waiting to be filtered.
585  */
586  FFFrameQueue fifo;
587 
588  /**
589  * If set, the source filter can not generate a frame as is.
590  * The goal is to avoid repeatedly calling the request_frame() method on
591  * the same link.
592  */
593  int frame_blocked_in;
594 
595  /**
596  * Link input status.
597  * If not zero, all attempts of filter_frame will fail with the
598  * corresponding code.
599  */
600  int status_in;
601 
602  /**
603  * Timestamp of the input status change.
604  */
605  int64_t status_in_pts;
606 
607  /**
608  * Link output status.
609  * If not zero, all attempts of request_frame will fail with the
610  * corresponding code.
611  */
612  int status_out;
613 
614 #endif /* FF_INTERNAL_FIELDS */
615 
616 };
617 
618 /**
619  * Link two filters together.
620  *
621  * @param src the source filter
622  * @param srcpad index of the output pad on the source filter
623  * @param dst the destination filter
624  * @param dstpad index of the input pad on the destination filter
625  * @return zero on success
626  */
627 int avfilter_link(AVFilterContext *src, unsigned srcpad,
628  AVFilterContext *dst, unsigned dstpad);
629 
630 /**
631  * Free the link in *link, and set its pointer to NULL.
632  */
633 void avfilter_link_free(AVFilterLink **link);
634 
635 /**
636  * Get the number of channels of a link.
637  */
639 
640 /**
641  * Set the closed field of a link.
642  * @deprecated applications are not supposed to mess with links, they should
643  * close the sinks.
644  */
646 void avfilter_link_set_closed(AVFilterLink *link, int closed);
647 
648 /**
649  * Negotiate the media format, dimensions, etc of all inputs to a filter.
650  *
651  * @param filter the filter to negotiate the properties for its inputs
652  * @return zero on successful negotiation
653  */
655 
656 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
657 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
658 
659 /**
660  * Make the filter instance process a command.
661  * It is recommended to use avfilter_graph_send_command().
662  */
663 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
664 
665 /** Initialize the filter system. Register all builtin filters. */
666 void avfilter_register_all(void);
667 
668 #if FF_API_OLD_FILTER_REGISTER
669 /** Uninitialize the filter system. Unregister all filters. */
671 void avfilter_uninit(void);
672 #endif
673 
674 /**
675  * Register a filter. This is only needed if you plan to use
676  * avfilter_get_by_name later to lookup the AVFilter structure by name. A
677  * filter can still by instantiated with avfilter_graph_alloc_filter even if it
678  * is not registered.
679  *
680  * @param filter the filter to register
681  * @return 0 if the registration was successful, a negative value
682  * otherwise
683  */
685 
686 /**
687  * Get a filter definition matching the given name.
688  *
689  * @param name the filter name to find
690  * @return the filter definition, if any matching one is registered.
691  * NULL if none found.
692  */
693 #if !FF_API_NOCONST_GET_NAME
694 const
695 #endif
696 AVFilter *avfilter_get_by_name(const char *name);
697 
698 /**
699  * Iterate over all registered filters.
700  * @return If prev is non-NULL, next registered filter after prev or NULL if
701  * prev is the last filter. If prev is NULL, return the first registered filter.
702  */
703 const AVFilter *avfilter_next(const AVFilter *prev);
704 
705 #if FF_API_OLD_FILTER_REGISTER
706 /**
707  * If filter is NULL, returns a pointer to the first registered filter pointer,
708  * if filter is non-NULL, returns the next pointer after filter.
709  * If the returned pointer points to NULL, the last registered filter
710  * was already reached.
711  * @deprecated use avfilter_next()
712  */
714 AVFilter **av_filter_next(AVFilter **filter);
715 #endif
716 
717 #if FF_API_AVFILTER_OPEN
718 /**
719  * Create a filter instance.
720  *
721  * @param filter_ctx put here a pointer to the created filter context
722  * on success, NULL on failure
723  * @param filter the filter to create an instance of
724  * @param inst_name Name to give to the new instance. Can be NULL for none.
725  * @return >= 0 in case of success, a negative error code otherwise
726  * @deprecated use avfilter_graph_alloc_filter() instead
727  */
729 int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name);
730 #endif
731 
732 
733 #if FF_API_AVFILTER_INIT_FILTER
734 /**
735  * Initialize a filter.
736  *
737  * @param filter the filter to initialize
738  * @param args A string of parameters to use when initializing the filter.
739  * The format and meaning of this string varies by filter.
740  * @param opaque Any extra non-string data needed by the filter. The meaning
741  * of this parameter varies by filter.
742  * @return zero on success
743  */
745 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
746 #endif
747 
748 /**
749  * Initialize a filter with the supplied parameters.
750  *
751  * @param ctx uninitialized filter context to initialize
752  * @param args Options to initialize the filter with. This must be a
753  * ':'-separated list of options in the 'key=value' form.
754  * May be NULL if the options have been set directly using the
755  * AVOptions API or there are no options that need to be set.
756  * @return 0 on success, a negative AVERROR on failure
757  */
758 int avfilter_init_str(AVFilterContext *ctx, const char *args);
759 
760 /**
761  * Initialize a filter with the supplied dictionary of options.
762  *
763  * @param ctx uninitialized filter context to initialize
764  * @param options An AVDictionary filled with options for this filter. On
765  * return this parameter will be destroyed and replaced with
766  * a dict containing options that were not found. This dictionary
767  * must be freed by the caller.
768  * May be NULL, then this function is equivalent to
769  * avfilter_init_str() with the second parameter set to NULL.
770  * @return 0 on success, a negative AVERROR on failure
771  *
772  * @note This function and avfilter_init_str() do essentially the same thing,
773  * the difference is in manner in which the options are passed. It is up to the
774  * calling code to choose whichever is more preferable. The two functions also
775  * behave differently when some of the provided options are not declared as
776  * supported by the filter. In such a case, avfilter_init_str() will fail, but
777  * this function will leave those extra options in the options AVDictionary and
778  * continue as usual.
779  */
781 
782 /**
783  * Free a filter context. This will also remove the filter from its
784  * filtergraph's list of filters.
785  *
786  * @param filter the filter to free
787  */
789 
790 /**
791  * Insert a filter in the middle of an existing link.
792  *
793  * @param link the link into which the filter should be inserted
794  * @param filt the filter to be inserted
795  * @param filt_srcpad_idx the input pad on the filter to connect
796  * @param filt_dstpad_idx the output pad on the filter to connect
797  * @return zero on success
798  */
800  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
801 
802 /**
803  * @return AVClass for AVFilterContext.
804  *
805  * @see av_opt_find().
806  */
807 const AVClass *avfilter_get_class(void);
808 
810 
811 /**
812  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
813  * executed multiple times, possibly in parallel.
814  *
815  * @param ctx the filter context the job belongs to
816  * @param arg an opaque parameter passed through from @ref
817  * AVFilterGraph.execute
818  * @param jobnr the index of the job being executed
819  * @param nb_jobs the total number of jobs
820  *
821  * @return 0 on success, a negative AVERROR on error
822  */
823 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
824 
825 /**
826  * A function executing multiple jobs, possibly in parallel.
827  *
828  * @param ctx the filter context to which the jobs belong
829  * @param func the function to be called multiple times
830  * @param arg the argument to be passed to func
831  * @param ret a nb_jobs-sized array to be filled with return values from each
832  * invocation of func
833  * @param nb_jobs the number of jobs to execute
834  *
835  * @return 0 on success, a negative AVERROR on error
836  */
838  void *arg, int *ret, int nb_jobs);
839 
840 typedef struct AVFilterGraph {
843  unsigned nb_filters;
844 
845  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
846 #if FF_API_LAVR_OPTS
847  attribute_deprecated char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters
848 #endif
849 
850  /**
851  * Type of multithreading allowed for filters in this graph. A combination
852  * of AVFILTER_THREAD_* flags.
853  *
854  * May be set by the caller at any point, the setting will apply to all
855  * filters initialized after that. The default is allowing everything.
856  *
857  * When a filter in this graph is initialized, this field is combined using
858  * bit AND with AVFilterContext.thread_type to get the final mask used for
859  * determining allowed threading types. I.e. a threading type needs to be
860  * set in both to be allowed.
861  */
863 
864  /**
865  * Maximum number of threads used by filters in this graph. May be set by
866  * the caller before adding any filters to the filtergraph. Zero (the
867  * default) means that the number of threads is determined automatically.
868  */
870 
871  /**
872  * Opaque object for libavfilter internal use.
873  */
875 
876  /**
877  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
878  * be used from callbacks like @ref AVFilterGraph.execute.
879  * Libavfilter will not touch this field in any way.
880  */
881  void *opaque;
882 
883  /**
884  * This callback may be set by the caller immediately after allocating the
885  * graph and before adding any filters to it, to provide a custom
886  * multithreading implementation.
887  *
888  * If set, filters with slice threading capability will call this callback
889  * to execute multiple jobs in parallel.
890  *
891  * If this field is left unset, libavfilter will use its internal
892  * implementation, which may or may not be multithreaded depending on the
893  * platform and build options.
894  */
896 
897  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
898 
899  /**
900  * Private fields
901  *
902  * The following fields are for internal use only.
903  * Their type, offset, number and semantic can change without notice.
904  */
905 
908 
910 } AVFilterGraph;
911 
912 /**
913  * Allocate a filter graph.
914  *
915  * @return the allocated filter graph on success or NULL.
916  */
918 
919 /**
920  * Create a new filter instance in a filter graph.
921  *
922  * @param graph graph in which the new filter will be used
923  * @param filter the filter to create an instance of
924  * @param name Name to give to the new instance (will be copied to
925  * AVFilterContext.name). This may be used by the caller to identify
926  * different filters, libavfilter itself assigns no semantics to
927  * this parameter. May be NULL.
928  *
929  * @return the context of the newly created filter instance (note that it is
930  * also retrievable directly through AVFilterGraph.filters or with
931  * avfilter_graph_get_filter()) on success or NULL on failure.
932  */
934  const AVFilter *filter,
935  const char *name);
936 
937 /**
938  * Get a filter instance identified by instance name from graph.
939  *
940  * @param graph filter graph to search through.
941  * @param name filter instance name (should be unique in the graph).
942  * @return the pointer to the found filter instance or NULL if it
943  * cannot be found.
944  */
946 
947 #if FF_API_AVFILTER_OPEN
948 /**
949  * Add an existing filter instance to a filter graph.
950  *
951  * @param graphctx the filter graph
952  * @param filter the filter to be added
953  *
954  * @deprecated use avfilter_graph_alloc_filter() to allocate a filter in a
955  * filter graph
956  */
958 int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
959 #endif
960 
961 /**
962  * Create and add a filter instance into an existing graph.
963  * The filter instance is created from the filter filt and inited
964  * with the parameters args and opaque.
965  *
966  * In case of success put in *filt_ctx the pointer to the created
967  * filter instance, otherwise set *filt_ctx to NULL.
968  *
969  * @param name the instance name to give to the created filter instance
970  * @param graph_ctx the filter graph
971  * @return a negative AVERROR error code in case of failure, a non
972  * negative value otherwise
973  */
975  const char *name, const char *args, void *opaque,
976  AVFilterGraph *graph_ctx);
977 
978 /**
979  * Enable or disable automatic format conversion inside the graph.
980  *
981  * Note that format conversion can still happen inside explicitly inserted
982  * scale and aresample filters.
983  *
984  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
985  */
987 
988 enum {
989  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
990  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
991 };
992 
993 /**
994  * Check validity and configure all the links and formats in the graph.
995  *
996  * @param graphctx the filter graph
997  * @param log_ctx context used for logging
998  * @return >= 0 in case of success, a negative AVERROR code otherwise
999  */
1000 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1001 
1002 /**
1003  * Free a graph, destroy its links, and set *graph to NULL.
1004  * If *graph is NULL, do nothing.
1005  */
1006 void avfilter_graph_free(AVFilterGraph **graph);
1007 
1008 /**
1009  * A linked-list of the inputs/outputs of the filter chain.
1010  *
1011  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1012  * where it is used to communicate open (unlinked) inputs and outputs from and
1013  * to the caller.
1014  * This struct specifies, per each not connected pad contained in the graph, the
1015  * filter context and the pad index required for establishing a link.
1016  */
1017 typedef struct AVFilterInOut {
1018  /** unique name for this input/output in the list */
1019  char *name;
1020 
1021  /** filter context associated to this input/output */
1023 
1024  /** index of the filt_ctx pad to use for linking */
1025  int pad_idx;
1026 
1027  /** next input/input in the list, NULL if this is the last */
1029 } AVFilterInOut;
1030 
1031 /**
1032  * Allocate a single AVFilterInOut entry.
1033  * Must be freed with avfilter_inout_free().
1034  * @return allocated AVFilterInOut on success, NULL on failure.
1035  */
1037 
1038 /**
1039  * Free the supplied list of AVFilterInOut and set *inout to NULL.
1040  * If *inout is NULL, do nothing.
1041  */
1042 void avfilter_inout_free(AVFilterInOut **inout);
1043 
1044 /**
1045  * Add a graph described by a string to a graph.
1046  *
1047  * @note The caller must provide the lists of inputs and outputs,
1048  * which therefore must be known before calling the function.
1049  *
1050  * @note The inputs parameter describes inputs of the already existing
1051  * part of the graph; i.e. from the point of view of the newly created
1052  * part, they are outputs. Similarly the outputs parameter describes
1053  * outputs of the already existing filters, which are provided as
1054  * inputs to the parsed filters.
1055  *
1056  * @param graph the filter graph where to link the parsed graph context
1057  * @param filters string to be parsed
1058  * @param inputs linked list to the inputs of the graph
1059  * @param outputs linked list to the outputs of the graph
1060  * @return zero on success, a negative AVERROR code on error
1061  */
1062 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1064  void *log_ctx);
1065 
1066 /**
1067  * Add a graph described by a string to a graph.
1068  *
1069  * In the graph filters description, if the input label of the first
1070  * filter is not specified, "in" is assumed; if the output label of
1071  * the last filter is not specified, "out" is assumed.
1072  *
1073  * @param graph the filter graph where to link the parsed graph context
1074  * @param filters string to be parsed
1075  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1076  * If non-NULL, *inputs is updated to contain the list of open inputs
1077  * after the parsing, should be freed with avfilter_inout_free().
1078  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1079  * If non-NULL, *outputs is updated to contain the list of open outputs
1080  * after the parsing, should be freed with avfilter_inout_free().
1081  * @return non negative on success, a negative AVERROR code on error
1082  */
1083 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1085  void *log_ctx);
1086 
1087 /**
1088  * Add a graph described by a string to a graph.
1089  *
1090  * @param[in] graph the filter graph where to link the parsed graph context
1091  * @param[in] filters string to be parsed
1092  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1093  * parsed graph will be returned here. It is to be freed
1094  * by the caller using avfilter_inout_free().
1095  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1096  * parsed graph will be returned here. It is to be freed by the
1097  * caller using avfilter_inout_free().
1098  * @return zero on success, a negative AVERROR code on error
1099  *
1100  * @note This function returns the inputs and outputs that are left
1101  * unlinked after parsing the graph and the caller then deals with
1102  * them.
1103  * @note This function makes no reference whatsoever to already
1104  * existing parts of the graph and the inputs parameter will on return
1105  * contain inputs of the newly parsed part of the graph. Analogously
1106  * the outputs parameter will contain outputs of the newly created
1107  * filters.
1108  */
1109 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1112 
1113 /**
1114  * Send a command to one or more filter instances.
1115  *
1116  * @param graph the filter graph
1117  * @param target the filter(s) to which the command should be sent
1118  * "all" sends to all filters
1119  * otherwise it can be a filter or filter instance name
1120  * which will send the command to all matching filters.
1121  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1122  * @param arg the argument for the command
1123  * @param res a buffer with size res_size where the filter(s) can return a response.
1124  *
1125  * @returns >=0 on success otherwise an error code.
1126  * AVERROR(ENOSYS) on unsupported commands
1127  */
1128 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1129 
1130 /**
1131  * Queue a command for one or more filter instances.
1132  *
1133  * @param graph the filter graph
1134  * @param target the filter(s) to which the command should be sent
1135  * "all" sends to all filters
1136  * otherwise it can be a filter or filter instance name
1137  * which will send the command to all matching filters.
1138  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1139  * @param arg the argument for the command
1140  * @param ts time at which the command should be sent to the filter
1141  *
1142  * @note As this executes commands after this function returns, no return code
1143  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1144  */
1145 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1146 
1147 
1148 /**
1149  * Dump a graph into a human-readable string representation.
1150  *
1151  * @param graph the graph to dump
1152  * @param options formatting options; currently ignored
1153  * @return a string, or NULL in case of memory allocation failure;
1154  * the string must be freed using av_free
1155  */
1156 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1157 
1158 /**
1159  * Request a frame on the oldest sink link.
1160  *
1161  * If the request returns AVERROR_EOF, try the next.
1162  *
1163  * Note that this function is not meant to be the sole scheduling mechanism
1164  * of a filtergraph, only a convenience function to help drain a filtergraph
1165  * in a balanced way under normal circumstances.
1166  *
1167  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1168  * some of the sinks during the process.
1169  * When there are multiple sink links, in case the requested link
1170  * returns an EOF, this may cause a filter to flush pending frames
1171  * which are sent to another sink link, although unrequested.
1172  *
1173  * @return the return value of ff_request_frame(),
1174  * or AVERROR_EOF if all links returned AVERROR_EOF
1175  */
1177 
1178 /**
1179  * @}
1180  */
1181 
1182 #endif /* AVFILTER_AVFILTER_H */
AVFilterContext ** filters
Definition: avfilter.h:842
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:369
int sink_links_count
Definition: avfilter.h:907
This structure describes decoded (raw) audio or video data.
Definition: frame.h:194
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:862
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:789
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:80
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:218
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:1028
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:1084
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:379
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:267
#define src
Definition: vp8dsp.c:254
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:358
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:370
Macro definitions for various function/variable attributes.
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:386
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:845
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:340
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:269
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:331
char * name
name of this filter instance
Definition: avfilter.h:328
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:895
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:334
const char * avfilter_license(void)
Return the libavfilter license.
Definition: avfilter.c:88
unsigned ready
Ready status of the filter.
Definition: avfilter.h:393
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, uint8_t clip)
Definition: cfhd.c:80
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:187
void avfilter_register_all(void)
Initialize the filter system.
Definition: allfilters.c:391
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:869
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:275
static int flags
Definition: log.c:57
const AVFilter * avfilter_next(const AVFilter *prev)
Iterate over all registered filters.
Definition: avfilter.c:594
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:243
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:291
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
const OptionDef options[]
Definition: ffserver.c:3952
A filter pad used for either input or output.
Definition: internal.h:54
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:330
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:823
int avfilter_link_get_channels(AVFilterLink *link)
Get the number of channels of a link.
Definition: avfilter.c:186
const AVClass * av_class
Definition: avfilter.h:841
unsigned nb_outputs
number of output pads
Definition: avfilter.h:336
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:338
char * enable_str
enable expression string
Definition: avfilter.h:367
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:231
static FilteringContext * filter_ctx
Definition: transcoding.c:46
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:906
reference-counted frame API
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: avfilter.c:564
attribute_deprecated void avfilter_link_set_closed(AVFilterLink *link, int closed)
Set the closed field of a link.
Definition: avfilter.c:233
unsigned nb_inputs
number of input pads
Definition: avfilter.h:332
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
AVFormatContext * ctx
Definition: movenc.c:48
all automatic conversions disabled
Definition: avfilter.h:990
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:271
static const AVFilterPad outputs[]
Definition: af_afftfilt.c:386
int(* init_opaque)(AVFilterContext *ctx, void *opaque)
Filter initialization function, alternative to the init() callback.
Definition: avfilter.h:298
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1022
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:960
const AVFilterPad * inputs
List of inputs, terminated by a zeroed element.
Definition: avfilter.h:164
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1647
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1017
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:238
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:837
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:182
static const AVFilterPad inputs[]
Definition: af_afftfilt.c:376
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:537
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
all automatic conversions enabled
Definition: avfilter.h:989
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:1025
Rational number (pair of numerator and denominator).
Definition: rational.h:58
struct AVFilter * next
Used by the filter registration system.
Definition: avfilter.h:277
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:843
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:1079
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:335
char * name
unique name for this input/output in the list
Definition: avfilter.h:1019
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:923
A reference to a data buffer.
Definition: buffer.h:81
void * opaque
Opaque user data.
Definition: avfilter.h:881
int
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:365
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:155
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:897
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:578
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:368
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:324
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:323
int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
Definition: avfilter.c:610
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:312
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:326
unsigned disable_auto_convert
Definition: avfilter.h:909
const char * name
Definition: opengl_enc.c:103