FFmpeg
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;
72 
73 #if FF_API_PAD_COUNT
74 /**
75  * Get the number of elements in an AVFilter's inputs or outputs array.
76  *
77  * @deprecated Use avfilter_filter_pad_count() instead.
78  */
80 int avfilter_pad_count(const AVFilterPad *pads);
81 #endif
82 
83 /**
84  * Get the name of an AVFilterPad.
85  *
86  * @param pads an array of AVFilterPads
87  * @param pad_idx index of the pad in the array; it is the caller's
88  * responsibility to ensure the index is valid
89  *
90  * @return name of the pad_idx'th pad in pads
91  */
92 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
93 
94 /**
95  * Get the type of an AVFilterPad.
96  *
97  * @param pads an array of AVFilterPads
98  * @param pad_idx index of the pad in the array; it is the caller's
99  * responsibility to ensure the index is valid
100  *
101  * @return type of the pad_idx'th pad in pads
102  */
103 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
104 
105 /**
106  * The number of the filter inputs is not determined just by AVFilter.inputs.
107  * The filter might add additional inputs during initialization depending on the
108  * options supplied to it.
109  */
110 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
111 /**
112  * The number of the filter outputs is not determined just by AVFilter.outputs.
113  * The filter might add additional outputs during initialization depending on
114  * the options supplied to it.
115  */
116 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
117 /**
118  * The filter supports multithreading by splitting frames into multiple parts
119  * and processing them concurrently.
120  */
121 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
122 /**
123  * Some filters support a generic "enable" expression option that can be used
124  * to enable or disable a filter in the timeline. Filters supporting this
125  * option have this flag set. When the enable expression is false, the default
126  * no-op filter_frame() function is called in place of the filter_frame()
127  * callback defined on each input pad, thus the frame is passed unchanged to
128  * the next filters.
129  */
130 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
131 /**
132  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
133  * have its filter_frame() callback(s) called as usual even when the enable
134  * expression is false. The filter will disable filtering within the
135  * filter_frame() callback(s) itself, for example executing code depending on
136  * the AVFilterContext->is_disabled value.
137  */
138 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
139 /**
140  * Handy mask to test whether the filter supports or no the timeline feature
141  * (internally or generically).
142  */
143 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
144 
145 /**
146  * Filter definition. This defines the pads a filter contains, and all the
147  * callback functions used to interact with the filter.
148  */
149 typedef struct AVFilter {
150  /**
151  * Filter name. Must be non-NULL and unique among filters.
152  */
153  const char *name;
154 
155  /**
156  * A description of the filter. May be NULL.
157  *
158  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
159  */
160  const char *description;
161 
162  /**
163  * List of static inputs.
164  *
165  * NULL if there are no (static) inputs. Instances of filters with
166  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
167  * this list.
168  */
170 
171  /**
172  * List of static outputs.
173  *
174  * NULL if there are no (static) outputs. Instances of filters with
175  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
176  * this list.
177  */
179 
180  /**
181  * A class for the private data, used to declare filter private AVOptions.
182  * This field is NULL for filters that do not declare any options.
183  *
184  * If this field is non-NULL, the first member of the filter private data
185  * must be a pointer to AVClass, which will be set by libavfilter generic
186  * code to this class.
187  */
189 
190  /**
191  * A combination of AVFILTER_FLAG_*
192  */
193  int flags;
194 
195  /*****************************************************************
196  * All fields below this line are not part of the public API. They
197  * may not be used outside of libavfilter and can be changed and
198  * removed at will.
199  * New public fields should be added right above.
200  *****************************************************************
201  */
202 
203  /**
204  * The number of entries in the list of inputs.
205  */
206  uint16_t nb_inputs;
207 
208  /**
209  * The number of entries in the list of outputs.
210  */
211  uint16_t nb_outputs;
212 
213  /**
214  * Filter pre-initialization function
215  *
216  * This callback will be called immediately after the filter context is
217  * allocated, to allow allocating and initing sub-objects.
218  *
219  * If this callback is not NULL, the uninit callback will be called on
220  * allocation failure.
221  *
222  * @return 0 on success,
223  * AVERROR code on failure (but the code will be
224  * dropped and treated as ENOMEM by the calling code)
225  */
227 
228  /**
229  * Filter initialization function.
230  *
231  * This callback will be called only once during the filter lifetime, after
232  * all the options have been set, but before links between filters are
233  * established and format negotiation is done.
234  *
235  * Basic filter initialization should be done here. Filters with dynamic
236  * inputs and/or outputs should create those inputs/outputs here based on
237  * provided options. No more changes to this filter's inputs/outputs can be
238  * done after this callback.
239  *
240  * This callback must not assume that the filter links exist or frame
241  * parameters are known.
242  *
243  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
244  * initialization fails, so this callback does not have to clean up on
245  * failure.
246  *
247  * @return 0 on success, a negative AVERROR on failure
248  */
250 
251  /**
252  * Should be set instead of @ref AVFilter.init "init" by the filters that
253  * want to pass a dictionary of AVOptions to nested contexts that are
254  * allocated during init.
255  *
256  * On return, the options dict should be freed and replaced with one that
257  * contains all the options which could not be processed by this filter (or
258  * with NULL if all the options were processed).
259  *
260  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
261  */
263 
264  /**
265  * Filter uninitialization function.
266  *
267  * Called only once right before the filter is freed. Should deallocate any
268  * memory held by the filter, release any buffer references, etc. It does
269  * not need to deallocate the AVFilterContext.priv memory itself.
270  *
271  * This callback may be called even if @ref AVFilter.init "init" was not
272  * called or failed, so it must be prepared to handle such a situation.
273  */
275 
276  /**
277  * Query formats supported by the filter on its inputs and outputs.
278  *
279  * This callback is called after the filter is initialized (so the inputs
280  * and outputs are fixed), shortly before the format negotiation. This
281  * callback may be called more than once.
282  *
283  * This callback must set AVFilterLink.outcfg.formats on every input link and
284  * AVFilterLink.incfg.formats on every output link to a list of pixel/sample
285  * formats that the filter supports on that link. For audio links, this
286  * filter must also set @ref AVFilterLink.incfg.samplerates "in_samplerates" /
287  * @ref AVFilterLink.outcfg.samplerates "out_samplerates" and
288  * @ref AVFilterLink.incfg.channel_layouts "in_channel_layouts" /
289  * @ref AVFilterLink.outcfg.channel_layouts "out_channel_layouts" analogously.
290  *
291  * This callback may be NULL for filters with one input, in which case
292  * libavfilter assumes that it supports all input formats and preserves
293  * them on output.
294  *
295  * @return zero on success, a negative value corresponding to an
296  * AVERROR code otherwise
297  */
299 
300  int priv_size; ///< size of private data to allocate for the filter
301 
302  int flags_internal; ///< Additional flags for avfilter internal use only.
303 
304  /**
305  * Make the filter instance process a command.
306  *
307  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
308  * @param arg the argument for the command
309  * @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.
310  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
311  * time consuming then a filter should treat it like an unsupported command
312  *
313  * @returns >=0 on success otherwise an error code.
314  * AVERROR(ENOSYS) on unsupported commands
315  */
316  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
317 
318  /**
319  * Filter activation function.
320  *
321  * Called when any processing is needed from the filter, instead of any
322  * filter_frame and request_frame on pads.
323  *
324  * The function must examine inlinks and outlinks and perform a single
325  * step of processing. If there is nothing to do, the function must do
326  * nothing and not return an error. If more steps are or may be
327  * possible, it must use ff_filter_set_ready() to schedule another
328  * activation.
329  */
331 } AVFilter;
332 
333 /**
334  * Get the number of elements in an AVFilter's inputs or outputs array.
335  */
336 unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
337 
338 /**
339  * Process multiple parts of the frame concurrently.
340  */
341 #define AVFILTER_THREAD_SLICE (1 << 0)
342 
343 typedef struct AVFilterInternal AVFilterInternal;
344 
345 /** An instance of a filter */
347  const AVClass *av_class; ///< needed for av_log() and filters common options
348 
349  const AVFilter *filter; ///< the AVFilter of which this is an instance
350 
351  char *name; ///< name of this filter instance
352 
353  AVFilterPad *input_pads; ///< array of input pads
354  AVFilterLink **inputs; ///< array of pointers to input links
355  unsigned nb_inputs; ///< number of input pads
356 
357  AVFilterPad *output_pads; ///< array of output pads
358  AVFilterLink **outputs; ///< array of pointers to output links
359  unsigned nb_outputs; ///< number of output pads
360 
361  void *priv; ///< private data for use by the filter
362 
363  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
364 
365  /**
366  * Type of multithreading being allowed/used. A combination of
367  * AVFILTER_THREAD_* flags.
368  *
369  * May be set by the caller before initializing the filter to forbid some
370  * or all kinds of multithreading for this filter. The default is allowing
371  * everything.
372  *
373  * When the filter is initialized, this field is combined using bit AND with
374  * AVFilterGraph.thread_type to get the final mask used for determining
375  * allowed threading types. I.e. a threading type needs to be set in both
376  * to be allowed.
377  *
378  * After the filter is initialized, libavfilter sets this field to the
379  * threading type that is actually used (0 for no multithreading).
380  */
382 
383  /**
384  * An opaque struct for libavfilter internal use.
385  */
386  AVFilterInternal *internal;
387 
389 
390  char *enable_str; ///< enable expression string
391  void *enable; ///< parsed expression (AVExpr*)
392  double *var_values; ///< variable values for the enable expression
393  int is_disabled; ///< the enabled state from the last expression evaluation
394 
395  /**
396  * For filters which will create hardware frames, sets the device the
397  * filter should create them in. All other filters will ignore this field:
398  * in particular, a filter which consumes or processes hardware frames will
399  * instead use the hw_frames_ctx field in AVFilterLink to carry the
400  * hardware context information.
401  */
403 
404  /**
405  * Max number of threads allowed in this filter instance.
406  * If <= 0, its value is ignored.
407  * Overrides global number of threads set per filter graph.
408  */
410 
411  /**
412  * Ready status of the filter.
413  * A non-0 value means that the filter needs activating;
414  * a higher value suggests a more urgent activation.
415  */
416  unsigned ready;
417 
418  /**
419  * Sets the number of extra hardware frames which the filter will
420  * allocate on its output links for use in following filters or by
421  * the caller.
422  *
423  * Some hardware filters require all frames that they will use for
424  * output to be defined in advance before filtering starts. For such
425  * filters, any hardware frame pools used for output must therefore be
426  * of fixed size. The extra frames set here are on top of any number
427  * that the filter needs internally in order to operate normally.
428  *
429  * This field must be set before the graph containing this filter is
430  * configured.
431  */
433 };
434 
435 /**
436  * Lists of formats / etc. supported by an end of a link.
437  *
438  * This structure is directly part of AVFilterLink, in two copies:
439  * one for the source filter, one for the destination filter.
440 
441  * These lists are used for negotiating the format to actually be used,
442  * which will be loaded into the format and channel_layout members of
443  * AVFilterLink, when chosen.
444  */
445 typedef struct AVFilterFormatsConfig {
446 
447  /**
448  * List of supported formats (pixel or sample).
449  */
451 
452  /**
453  * Lists of supported sample rates, only for audio.
454  */
456 
457  /**
458  * Lists of supported channel layouts, only for audio.
459  */
461 
463 
464 /**
465  * A link between two filters. This contains pointers to the source and
466  * destination filters between which this link exists, and the indexes of
467  * the pads involved. In addition, this link also contains the parameters
468  * which have been negotiated and agreed upon between the filter, such as
469  * image dimensions, format, etc.
470  *
471  * Applications must not normally access the link structure directly.
472  * Use the buffersrc and buffersink API instead.
473  * In the future, access to the header may be reserved for filters
474  * implementation.
475  */
476 struct AVFilterLink {
477  AVFilterContext *src; ///< source filter
478  AVFilterPad *srcpad; ///< output pad on the source filter
479 
480  AVFilterContext *dst; ///< dest filter
481  AVFilterPad *dstpad; ///< input pad on the dest filter
482 
483  enum AVMediaType type; ///< filter media type
484 
485  /* These parameters apply only to video */
486  int w; ///< agreed upon image width
487  int h; ///< agreed upon image height
488  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
489  /* These parameters apply only to audio */
490  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
491  int sample_rate; ///< samples per second
492 
493  int format; ///< agreed upon media format
494 
495  /**
496  * Define the time base used by the PTS of the frames/samples
497  * which will pass through this link.
498  * During the configuration stage, each filter is supposed to
499  * change only the output timebase, while the timebase of the
500  * input link is assumed to be an unchangeable property.
501  */
503 
504  /*****************************************************************
505  * All fields below this line are not part of the public API. They
506  * may not be used outside of libavfilter and can be changed and
507  * removed at will.
508  * New public fields should be added right above.
509  *****************************************************************
510  */
511 
512  /**
513  * Lists of supported formats / etc. supported by the input filter.
514  */
516 
517  /**
518  * Lists of supported formats / etc. supported by the output filter.
519  */
521 
522  /** stage of the initialization of the link properties (dimensions, etc) */
523  enum {
524  AVLINK_UNINIT = 0, ///< not started
525  AVLINK_STARTINIT, ///< started, but incomplete
526  AVLINK_INIT ///< complete
527  } init_state;
528 
529  /**
530  * Graph the filter belongs to.
531  */
533 
534  /**
535  * Current timestamp of the link, as defined by the most recent
536  * frame(s), in link time_base units.
537  */
538  int64_t current_pts;
539 
540  /**
541  * Current timestamp of the link, as defined by the most recent
542  * frame(s), in AV_TIME_BASE units.
543  */
544  int64_t current_pts_us;
545 
546  /**
547  * Index in the age array.
548  */
550 
551  /**
552  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
553  * if left to 0/0, will be automatically copied from the first input
554  * of the source filter if it exists.
555  *
556  * Sources should set it to the best estimation of the real frame rate.
557  * If the source frame rate is unknown or variable, set this to 1/0.
558  * Filters should update it if necessary depending on their function.
559  * Sinks can use it to set a default output frame rate.
560  * It is similar to the r_frame_rate field in AVStream.
561  */
563 
564  /**
565  * Minimum number of samples to filter at once. If filter_frame() is
566  * called with fewer samples, it will accumulate them in fifo.
567  * This field and the related ones must not be changed after filtering
568  * has started.
569  * If 0, all related fields are ignored.
570  */
572 
573  /**
574  * Maximum number of samples to filter at once. If filter_frame() is
575  * called with more samples, it will split them.
576  */
578 
579  /**
580  * Number of channels.
581  */
582  int channels;
583 
584  /**
585  * Number of past frames sent through the link.
586  */
588 
589  /**
590  * Number of past samples sent through the link.
591  */
593 
594  /**
595  * A pointer to a FFFramePool struct.
596  */
597  void *frame_pool;
598 
599  /**
600  * True if a frame is currently wanted on the output of this filter.
601  * Set when ff_request_frame() is called by the output,
602  * cleared when a frame is filtered.
603  */
605 
606  /**
607  * For hwaccel pixel formats, this should be a reference to the
608  * AVHWFramesContext describing the frames.
609  */
611 
612 #ifndef FF_INTERNAL_FIELDS
613 
614  /**
615  * Internal structure members.
616  * The fields below this limit are internal for libavfilter's use
617  * and must in no way be accessed by applications.
618  */
619  char reserved[0xF000];
620 
621 #else /* FF_INTERNAL_FIELDS */
622 
623  /**
624  * Queue of frames waiting to be filtered.
625  */
626  FFFrameQueue fifo;
627 
628  /**
629  * If set, the source filter can not generate a frame as is.
630  * The goal is to avoid repeatedly calling the request_frame() method on
631  * the same link.
632  */
633  int frame_blocked_in;
634 
635  /**
636  * Link input status.
637  * If not zero, all attempts of filter_frame will fail with the
638  * corresponding code.
639  */
640  int status_in;
641 
642  /**
643  * Timestamp of the input status change.
644  */
645  int64_t status_in_pts;
646 
647  /**
648  * Link output status.
649  * If not zero, all attempts of request_frame will fail with the
650  * corresponding code.
651  */
652  int status_out;
653 
654 #endif /* FF_INTERNAL_FIELDS */
655 
656 };
657 
658 /**
659  * Link two filters together.
660  *
661  * @param src the source filter
662  * @param srcpad index of the output pad on the source filter
663  * @param dst the destination filter
664  * @param dstpad index of the input pad on the destination filter
665  * @return zero on success
666  */
667 int avfilter_link(AVFilterContext *src, unsigned srcpad,
668  AVFilterContext *dst, unsigned dstpad);
669 
670 /**
671  * Free the link in *link, and set its pointer to NULL.
672  */
674 
675 /**
676  * Negotiate the media format, dimensions, etc of all inputs to a filter.
677  *
678  * @param filter the filter to negotiate the properties for its inputs
679  * @return zero on successful negotiation
680  */
682 
683 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
684 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
685 
686 /**
687  * Make the filter instance process a command.
688  * It is recommended to use avfilter_graph_send_command().
689  */
690 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
691 
692 /**
693  * Iterate over all registered filters.
694  *
695  * @param opaque a pointer where libavfilter will store the iteration state. Must
696  * point to NULL to start the iteration.
697  *
698  * @return the next registered filter or NULL when the iteration is
699  * finished
700  */
701 const AVFilter *av_filter_iterate(void **opaque);
702 
703 /**
704  * Get a filter definition matching the given name.
705  *
706  * @param name the filter name to find
707  * @return the filter definition, if any matching one is registered.
708  * NULL if none found.
709  */
710 const AVFilter *avfilter_get_by_name(const char *name);
711 
712 
713 /**
714  * Initialize a filter with the supplied parameters.
715  *
716  * @param ctx uninitialized filter context to initialize
717  * @param args Options to initialize the filter with. This must be a
718  * ':'-separated list of options in the 'key=value' form.
719  * May be NULL if the options have been set directly using the
720  * AVOptions API or there are no options that need to be set.
721  * @return 0 on success, a negative AVERROR on failure
722  */
723 int avfilter_init_str(AVFilterContext *ctx, const char *args);
724 
725 /**
726  * Initialize a filter with the supplied dictionary of options.
727  *
728  * @param ctx uninitialized filter context to initialize
729  * @param options An AVDictionary filled with options for this filter. On
730  * return this parameter will be destroyed and replaced with
731  * a dict containing options that were not found. This dictionary
732  * must be freed by the caller.
733  * May be NULL, then this function is equivalent to
734  * avfilter_init_str() with the second parameter set to NULL.
735  * @return 0 on success, a negative AVERROR on failure
736  *
737  * @note This function and avfilter_init_str() do essentially the same thing,
738  * the difference is in manner in which the options are passed. It is up to the
739  * calling code to choose whichever is more preferable. The two functions also
740  * behave differently when some of the provided options are not declared as
741  * supported by the filter. In such a case, avfilter_init_str() will fail, but
742  * this function will leave those extra options in the options AVDictionary and
743  * continue as usual.
744  */
746 
747 /**
748  * Free a filter context. This will also remove the filter from its
749  * filtergraph's list of filters.
750  *
751  * @param filter the filter to free
752  */
754 
755 /**
756  * Insert a filter in the middle of an existing link.
757  *
758  * @param link the link into which the filter should be inserted
759  * @param filt the filter to be inserted
760  * @param filt_srcpad_idx the input pad on the filter to connect
761  * @param filt_dstpad_idx the output pad on the filter to connect
762  * @return zero on success
763  */
765  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
766 
767 /**
768  * @return AVClass for AVFilterContext.
769  *
770  * @see av_opt_find().
771  */
772 const AVClass *avfilter_get_class(void);
773 
775 
776 /**
777  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
778  * executed multiple times, possibly in parallel.
779  *
780  * @param ctx the filter context the job belongs to
781  * @param arg an opaque parameter passed through from @ref
782  * AVFilterGraph.execute
783  * @param jobnr the index of the job being executed
784  * @param nb_jobs the total number of jobs
785  *
786  * @return 0 on success, a negative AVERROR on error
787  */
788 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
789 
790 /**
791  * A function executing multiple jobs, possibly in parallel.
792  *
793  * @param ctx the filter context to which the jobs belong
794  * @param func the function to be called multiple times
795  * @param arg the argument to be passed to func
796  * @param ret a nb_jobs-sized array to be filled with return values from each
797  * invocation of func
798  * @param nb_jobs the number of jobs to execute
799  *
800  * @return 0 on success, a negative AVERROR on error
801  */
803  void *arg, int *ret, int nb_jobs);
804 
805 typedef struct AVFilterGraph {
808  unsigned nb_filters;
809 
810  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
811 
812  /**
813  * Type of multithreading allowed for filters in this graph. A combination
814  * of AVFILTER_THREAD_* flags.
815  *
816  * May be set by the caller at any point, the setting will apply to all
817  * filters initialized after that. The default is allowing everything.
818  *
819  * When a filter in this graph is initialized, this field is combined using
820  * bit AND with AVFilterContext.thread_type to get the final mask used for
821  * determining allowed threading types. I.e. a threading type needs to be
822  * set in both to be allowed.
823  */
825 
826  /**
827  * Maximum number of threads used by filters in this graph. May be set by
828  * the caller before adding any filters to the filtergraph. Zero (the
829  * default) means that the number of threads is determined automatically.
830  */
832 
833  /**
834  * Opaque object for libavfilter internal use.
835  */
837 
838  /**
839  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
840  * be used from callbacks like @ref AVFilterGraph.execute.
841  * Libavfilter will not touch this field in any way.
842  */
843  void *opaque;
844 
845  /**
846  * This callback may be set by the caller immediately after allocating the
847  * graph and before adding any filters to it, to provide a custom
848  * multithreading implementation.
849  *
850  * If set, filters with slice threading capability will call this callback
851  * to execute multiple jobs in parallel.
852  *
853  * If this field is left unset, libavfilter will use its internal
854  * implementation, which may or may not be multithreaded depending on the
855  * platform and build options.
856  */
858 
859  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
860 
861  /**
862  * Private fields
863  *
864  * The following fields are for internal use only.
865  * Their type, offset, number and semantic can change without notice.
866  */
867 
870 
872 } AVFilterGraph;
873 
874 /**
875  * Allocate a filter graph.
876  *
877  * @return the allocated filter graph on success or NULL.
878  */
880 
881 /**
882  * Create a new filter instance in a filter graph.
883  *
884  * @param graph graph in which the new filter will be used
885  * @param filter the filter to create an instance of
886  * @param name Name to give to the new instance (will be copied to
887  * AVFilterContext.name). This may be used by the caller to identify
888  * different filters, libavfilter itself assigns no semantics to
889  * this parameter. May be NULL.
890  *
891  * @return the context of the newly created filter instance (note that it is
892  * also retrievable directly through AVFilterGraph.filters or with
893  * avfilter_graph_get_filter()) on success or NULL on failure.
894  */
896  const AVFilter *filter,
897  const char *name);
898 
899 /**
900  * Get a filter instance identified by instance name from graph.
901  *
902  * @param graph filter graph to search through.
903  * @param name filter instance name (should be unique in the graph).
904  * @return the pointer to the found filter instance or NULL if it
905  * cannot be found.
906  */
908 
909 /**
910  * Create and add a filter instance into an existing graph.
911  * The filter instance is created from the filter filt and inited
912  * with the parameter args. opaque is currently ignored.
913  *
914  * In case of success put in *filt_ctx the pointer to the created
915  * filter instance, otherwise set *filt_ctx to NULL.
916  *
917  * @param name the instance name to give to the created filter instance
918  * @param graph_ctx the filter graph
919  * @return a negative AVERROR error code in case of failure, a non
920  * negative value otherwise
921  */
923  const char *name, const char *args, void *opaque,
924  AVFilterGraph *graph_ctx);
925 
926 /**
927  * Enable or disable automatic format conversion inside the graph.
928  *
929  * Note that format conversion can still happen inside explicitly inserted
930  * scale and aresample filters.
931  *
932  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
933  */
935 
936 enum {
937  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
938  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
939 };
940 
941 /**
942  * Check validity and configure all the links and formats in the graph.
943  *
944  * @param graphctx the filter graph
945  * @param log_ctx context used for logging
946  * @return >= 0 in case of success, a negative AVERROR code otherwise
947  */
948 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
949 
950 /**
951  * Free a graph, destroy its links, and set *graph to NULL.
952  * If *graph is NULL, do nothing.
953  */
955 
956 /**
957  * A linked-list of the inputs/outputs of the filter chain.
958  *
959  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
960  * where it is used to communicate open (unlinked) inputs and outputs from and
961  * to the caller.
962  * This struct specifies, per each not connected pad contained in the graph, the
963  * filter context and the pad index required for establishing a link.
964  */
965 typedef struct AVFilterInOut {
966  /** unique name for this input/output in the list */
967  char *name;
968 
969  /** filter context associated to this input/output */
971 
972  /** index of the filt_ctx pad to use for linking */
973  int pad_idx;
974 
975  /** next input/input in the list, NULL if this is the last */
977 } AVFilterInOut;
978 
979 /**
980  * Allocate a single AVFilterInOut entry.
981  * Must be freed with avfilter_inout_free().
982  * @return allocated AVFilterInOut on success, NULL on failure.
983  */
985 
986 /**
987  * Free the supplied list of AVFilterInOut and set *inout to NULL.
988  * If *inout is NULL, do nothing.
989  */
990 void avfilter_inout_free(AVFilterInOut **inout);
991 
992 /**
993  * Add a graph described by a string to a graph.
994  *
995  * @note The caller must provide the lists of inputs and outputs,
996  * which therefore must be known before calling the function.
997  *
998  * @note The inputs parameter describes inputs of the already existing
999  * part of the graph; i.e. from the point of view of the newly created
1000  * part, they are outputs. Similarly the outputs parameter describes
1001  * outputs of the already existing filters, which are provided as
1002  * inputs to the parsed filters.
1003  *
1004  * @param graph the filter graph where to link the parsed graph context
1005  * @param filters string to be parsed
1006  * @param inputs linked list to the inputs of the graph
1007  * @param outputs linked list to the outputs of the graph
1008  * @return zero on success, a negative AVERROR code on error
1009  */
1012  void *log_ctx);
1013 
1014 /**
1015  * Add a graph described by a string to a graph.
1016  *
1017  * In the graph filters description, if the input label of the first
1018  * filter is not specified, "in" is assumed; if the output label of
1019  * the last filter is not specified, "out" is assumed.
1020  *
1021  * @param graph the filter graph where to link the parsed graph context
1022  * @param filters string to be parsed
1023  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1024  * If non-NULL, *inputs is updated to contain the list of open inputs
1025  * after the parsing, should be freed with avfilter_inout_free().
1026  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1027  * If non-NULL, *outputs is updated to contain the list of open outputs
1028  * after the parsing, should be freed with avfilter_inout_free().
1029  * @return non negative on success, a negative AVERROR code on error
1030  */
1033  void *log_ctx);
1034 
1035 /**
1036  * Add a graph described by a string to a graph.
1037  *
1038  * @param[in] graph the filter graph where to link the parsed graph context
1039  * @param[in] filters string to be parsed
1040  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1041  * parsed graph will be returned here. It is to be freed
1042  * by the caller using avfilter_inout_free().
1043  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1044  * parsed graph will be returned here. It is to be freed by the
1045  * caller using avfilter_inout_free().
1046  * @return zero on success, a negative AVERROR code on error
1047  *
1048  * @note This function returns the inputs and outputs that are left
1049  * unlinked after parsing the graph and the caller then deals with
1050  * them.
1051  * @note This function makes no reference whatsoever to already
1052  * existing parts of the graph and the inputs parameter will on return
1053  * contain inputs of the newly parsed part of the graph. Analogously
1054  * the outputs parameter will contain outputs of the newly created
1055  * filters.
1056  */
1060 
1061 /**
1062  * Send a command to one or more filter instances.
1063  *
1064  * @param graph the filter graph
1065  * @param target the filter(s) to which the command should be sent
1066  * "all" sends to all filters
1067  * otherwise it can be a filter or filter instance name
1068  * which will send the command to all matching filters.
1069  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1070  * @param arg the argument for the command
1071  * @param res a buffer with size res_size where the filter(s) can return a response.
1072  *
1073  * @returns >=0 on success otherwise an error code.
1074  * AVERROR(ENOSYS) on unsupported commands
1075  */
1076 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1077 
1078 /**
1079  * Queue a command for one or more filter instances.
1080  *
1081  * @param graph the filter graph
1082  * @param target the filter(s) to which the command should be sent
1083  * "all" sends to all filters
1084  * otherwise it can be a filter or filter instance name
1085  * which will send the command to all matching filters.
1086  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1087  * @param arg the argument for the command
1088  * @param ts time at which the command should be sent to the filter
1089  *
1090  * @note As this executes commands after this function returns, no return code
1091  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1092  */
1093 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1094 
1095 
1096 /**
1097  * Dump a graph into a human-readable string representation.
1098  *
1099  * @param graph the graph to dump
1100  * @param options formatting options; currently ignored
1101  * @return a string, or NULL in case of memory allocation failure;
1102  * the string must be freed using av_free
1103  */
1104 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1105 
1106 /**
1107  * Request a frame on the oldest sink link.
1108  *
1109  * If the request returns AVERROR_EOF, try the next.
1110  *
1111  * Note that this function is not meant to be the sole scheduling mechanism
1112  * of a filtergraph, only a convenience function to help drain a filtergraph
1113  * in a balanced way under normal circumstances.
1114  *
1115  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1116  * some of the sinks during the process.
1117  * When there are multiple sink links, in case the requested link
1118  * returns an EOF, this may cause a filter to flush pending frames
1119  * which are sent to another sink link, although unrequested.
1120  *
1121  * @return the return value of ff_request_frame(),
1122  * or AVERROR_EOF if all links returned AVERROR_EOF
1123  */
1125 
1126 /**
1127  * @}
1128  */
1129 
1130 #endif /* AVFILTER_AVFILTER_H */
func
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:68
AVFilterGraph::execute
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:857
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:85
AVFilterContext::nb_threads
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:409
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:455
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
avfilter_filter_pad_count
unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output)
Get the number of elements in an AVFilter's inputs or outputs array.
Definition: avfilter.c:595
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:831
avfilter_pad_get_name
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
Definition: avfilter.c:971
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:460
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:188
avfilter_action_func
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:788
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:392
rational.h
graph
fg outputs[0] graph
Definition: ffmpeg_filter.c:174
AVFilterContext::is_disabled
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:393
AVFilter::process_command
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:316
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:976
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:359
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:347
AVFilterGraph::disable_auto_convert
unsigned disable_auto_convert
Definition: avfilter.h:871
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:938
AVFilterContext::hw_device_ctx
AVBufferRef * hw_device_ctx
For filters which will create hardware frames, sets the device the filter should create them in.
Definition: avfilter.h:402
AVFilterGraphInternal
Definition: internal.h:133
filter
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:228
AVDictionary
Definition: dict.c:30
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:357
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:121
AVFilter::nb_inputs
uint16_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:206
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
avfilter_graph_create_filter
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.
Definition: avfiltergraph.c:140
avfilter_graph_alloc_filter
AVFilterContext * avfilter_graph_alloc_filter(AVFilterGraph *graph, const AVFilter *filter, const char *name)
Create a new filter instance in a filter graph.
Definition: avfiltergraph.c:168
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:361
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:363
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:390
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:84
avfilter_insert_filter
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:254
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:546
samplefmt.h
AVFilterContext::extra_hw_frames
int extra_hw_frames
Sets the number of extra hardware frames which the filter will allocate on its output links for use i...
Definition: avfilter.h:432
avfilter_config_links
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:291
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:843
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:302
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
Definition: avfilter.c:89
filters
#define filters(fmt, inverse, clip, i, c)
Definition: af_crystalizer.c:239
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:353
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:212
inputs
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Definition: filter_design.txt:243
avfilter_process_command
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:553
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:192
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:193
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AVFilterGraph::aresample_swr_opts
char * aresample_swr_opts
swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
Definition: avfilter.h:859
link
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a link
Definition: filter_design.txt:23
arg
const char * arg
Definition: jacosubdec.c:67
AVFilter::activate
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:330
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:557
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
AVFilterContext::thread_type
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:381
avfilter_graph_config
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
Definition: avfiltergraph.c:1160
AVFilter::outputs
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:178
avfilter_graph_set_auto_convert
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
Enable or disable automatic format conversion inside the graph.
Definition: avfiltergraph.c:163
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:807
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:354
AVFilterInternal
Definition: internal.h:139
src
#define src
Definition: vp8dsp.c:255
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:351
avfilter_inout_alloc
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
Definition: graphparser.c:207
avfilter_graph_get_filter
AVFilterContext * avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
Get a filter instance identified by instance name from graph.
Definition: avfiltergraph.c:288
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1288
AVFilterGraph
Definition: avfilter.h:805
avfilter_graph_parse2
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:418
AVFilterFormatsConfig
Lists of formats / etc.
Definition: avfilter.h:445
avfilter_pad_count
int avfilter_pad_count(const AVFilterPad *pads)
Definition: avfilter.c:575
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:973
FFFrameQueue
Queue of AVFrame pointers.
Definition: framequeue.h:53
AVFilterGraph::scale_sws_opts
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:810
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:355
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:806
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:388
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:970
avfilter_execute_func
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:802
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:226
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:162
avfilter_graph_queue_command
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.
Definition: avfiltergraph.c:1208
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:160
avfilter_link_free
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
Definition: avfilter.c:201
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
attributes.h
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:249
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:937
log.h
avfilter_graph_parse_ptr
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:549
AVFilterCommand
Definition: internal.h:34
AVFilterGraph::thread_type
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:824
filt
static const int8_t filt[NUMTAPS *2]
Definition: af_earwax.c:39
AVFilter::priv_size
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:300
AVFilter
Filter definition.
Definition: avfilter.h:149
ret
ret
Definition: filter_design.txt:187
AVFilterGraph::sink_links
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:868
pixfmt.h
avfilter_configuration
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
Definition: avfilter.c:84
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:155
dict.h
avfilter_pad_get_type
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
Definition: avfilter.c:976
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:896
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:391
AVFilterContext
An instance of a filter.
Definition: avfilter.h:346
avfilter_graph_parse
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:486
avutil.h
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVFilterFormatsConfig::formats
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition: avfilter.h:450
AVFilter::inputs
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:169
AVFilter::query_formats
int(* query_formats)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:298
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:274
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:758
status_in
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the then the processing requires a frame on this link and the filter is expected to make efforts in that direction The status of input links is stored by the status_in
Definition: filter_design.txt:154
AVFilter::nb_outputs
uint16_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:211
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:967
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
avfilter_graph_send_command
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.
Definition: avfiltergraph.c:1178
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:937
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:808
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:349
AVFilter::init_dict
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:262
int
int
Definition: ffmpeg_filter.c:156
avfilter_version
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
Definition: avfilter.c:78
avfilter_get_class
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1561
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:965
AVFilterGraph::sink_links_count
int sink_links_count
Definition: avfilter.h:869
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:416
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:358