FFmpeg  5.0
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  */
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  * The filter is a "metadata" filter - it does not modify the frame data in any
124  * way. It may only affect the metadata (i.e. those fields copied by
125  * av_frame_copy_props()).
126  *
127  * More precisely, this means:
128  * - video: the data of any frame output by the filter must be exactly equal to
129  * some frame that is received on one of its inputs. Furthermore, all frames
130  * produced on a given output must correspond to frames received on the same
131  * input and their order must be unchanged. Note that the filter may still
132  * drop or duplicate the frames.
133  * - audio: the data produced by the filter on any of its outputs (viewed e.g.
134  * as an array of interleaved samples) must be exactly equal to the data
135  * received by the filter on one of its inputs.
136  */
137 #define AVFILTER_FLAG_METADATA_ONLY (1 << 3)
138 /**
139  * Some filters support a generic "enable" expression option that can be used
140  * to enable or disable a filter in the timeline. Filters supporting this
141  * option have this flag set. When the enable expression is false, the default
142  * no-op filter_frame() function is called in place of the filter_frame()
143  * callback defined on each input pad, thus the frame is passed unchanged to
144  * the next filters.
145  */
146 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
147 /**
148  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
149  * have its filter_frame() callback(s) called as usual even when the enable
150  * expression is false. The filter will disable filtering within the
151  * filter_frame() callback(s) itself, for example executing code depending on
152  * the AVFilterContext->is_disabled value.
153  */
154 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
155 /**
156  * Handy mask to test whether the filter supports or no the timeline feature
157  * (internally or generically).
158  */
159 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
160 
161 /**
162  * Filter definition. This defines the pads a filter contains, and all the
163  * callback functions used to interact with the filter.
164  */
165 typedef struct AVFilter {
166  /**
167  * Filter name. Must be non-NULL and unique among filters.
168  */
169  const char *name;
170 
171  /**
172  * A description of the filter. May be NULL.
173  *
174  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
175  */
176  const char *description;
177 
178  /**
179  * List of static inputs.
180  *
181  * NULL if there are no (static) inputs. Instances of filters with
182  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
183  * this list.
184  */
186 
187  /**
188  * List of static outputs.
189  *
190  * NULL if there are no (static) outputs. Instances of filters with
191  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
192  * this list.
193  */
195 
196  /**
197  * A class for the private data, used to declare filter private AVOptions.
198  * This field is NULL for filters that do not declare any options.
199  *
200  * If this field is non-NULL, the first member of the filter private data
201  * must be a pointer to AVClass, which will be set by libavfilter generic
202  * code to this class.
203  */
205 
206  /**
207  * A combination of AVFILTER_FLAG_*
208  */
209  int flags;
210 
211  /*****************************************************************
212  * All fields below this line are not part of the public API. They
213  * may not be used outside of libavfilter and can be changed and
214  * removed at will.
215  * New public fields should be added right above.
216  *****************************************************************
217  */
218 
219  /**
220  * The number of entries in the list of inputs.
221  */
222  uint8_t nb_inputs;
223 
224  /**
225  * The number of entries in the list of outputs.
226  */
227  uint8_t nb_outputs;
228 
229  /**
230  * This field determines the state of the formats union.
231  * It is an enum FilterFormatsState value.
232  */
233  uint8_t formats_state;
234 
235  /**
236  * Filter pre-initialization function
237  *
238  * This callback will be called immediately after the filter context is
239  * allocated, to allow allocating and initing sub-objects.
240  *
241  * If this callback is not NULL, the uninit callback will be called on
242  * allocation failure.
243  *
244  * @return 0 on success,
245  * AVERROR code on failure (but the code will be
246  * dropped and treated as ENOMEM by the calling code)
247  */
248  int (*preinit)(AVFilterContext *ctx);
249 
250  /**
251  * Filter initialization function.
252  *
253  * This callback will be called only once during the filter lifetime, after
254  * all the options have been set, but before links between filters are
255  * established and format negotiation is done.
256  *
257  * Basic filter initialization should be done here. Filters with dynamic
258  * inputs and/or outputs should create those inputs/outputs here based on
259  * provided options. No more changes to this filter's inputs/outputs can be
260  * done after this callback.
261  *
262  * This callback must not assume that the filter links exist or frame
263  * parameters are known.
264  *
265  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
266  * initialization fails, so this callback does not have to clean up on
267  * failure.
268  *
269  * @return 0 on success, a negative AVERROR on failure
270  */
271  int (*init)(AVFilterContext *ctx);
272 
273  /**
274  * Should be set instead of @ref AVFilter.init "init" by the filters that
275  * want to pass a dictionary of AVOptions to nested contexts that are
276  * allocated during init.
277  *
278  * On return, the options dict should be freed and replaced with one that
279  * contains all the options which could not be processed by this filter (or
280  * with NULL if all the options were processed).
281  *
282  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
283  */
284  int (*init_dict)(AVFilterContext *ctx, AVDictionary **options);
285 
286  /**
287  * Filter uninitialization function.
288  *
289  * Called only once right before the filter is freed. Should deallocate any
290  * memory held by the filter, release any buffer references, etc. It does
291  * not need to deallocate the AVFilterContext.priv memory itself.
292  *
293  * This callback may be called even if @ref AVFilter.init "init" was not
294  * called or failed, so it must be prepared to handle such a situation.
295  */
296  void (*uninit)(AVFilterContext *ctx);
297 
298  /**
299  * The state of the following union is determined by formats_state.
300  * See the documentation of enum FilterFormatsState in internal.h.
301  */
302  union {
303  /**
304  * Query formats supported by the filter on its inputs and outputs.
305  *
306  * This callback is called after the filter is initialized (so the inputs
307  * and outputs are fixed), shortly before the format negotiation. This
308  * callback may be called more than once.
309  *
310  * This callback must set AVFilterLink.outcfg.formats on every input link
311  * and AVFilterLink.incfg.formats on every output link to a list of
312  * pixel/sample formats that the filter supports on that link. For audio
313  * links, this filter must also set @ref AVFilterLink.incfg.samplerates
314  * "in_samplerates" / @ref AVFilterLink.outcfg.samplerates "out_samplerates"
315  * and @ref AVFilterLink.incfg.channel_layouts "in_channel_layouts" /
316  * @ref AVFilterLink.outcfg.channel_layouts "out_channel_layouts" analogously.
317  *
318  * This callback must never be NULL if the union is in this state.
319  *
320  * @return zero on success, a negative value corresponding to an
321  * AVERROR code otherwise
322  */
324  /**
325  * A pointer to an array of admissible pixel formats delimited
326  * by AV_PIX_FMT_NONE. The generic code will use this list
327  * to indicate that this filter supports each of these pixel formats,
328  * provided that all inputs and outputs use the same pixel format.
329  *
330  * This list must never be NULL if the union is in this state.
331  * The type of all inputs and outputs of filters using this must
332  * be AVMEDIA_TYPE_VIDEO.
333  */
335  /**
336  * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
337  * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
338  * inputs and outputs.
339  *
340  * In addition to that the generic code will mark all inputs
341  * and all outputs as supporting all sample rates and every
342  * channel count and channel layout, as long as all inputs
343  * and outputs use the same sample rate and channel count/layout.
344  */
346  /**
347  * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
348  */
349  enum AVPixelFormat pix_fmt;
350  /**
351  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
352  */
355 
356  int priv_size; ///< size of private data to allocate for the filter
357 
358  int flags_internal; ///< Additional flags for avfilter internal use only.
359 
360  /**
361  * Make the filter instance process a command.
362  *
363  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
364  * @param arg the argument for the command
365  * @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.
366  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
367  * time consuming then a filter should treat it like an unsupported command
368  *
369  * @returns >=0 on success otherwise an error code.
370  * AVERROR(ENOSYS) on unsupported commands
371  */
372  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
373 
374  /**
375  * Filter activation function.
376  *
377  * Called when any processing is needed from the filter, instead of any
378  * filter_frame and request_frame on pads.
379  *
380  * The function must examine inlinks and outlinks and perform a single
381  * step of processing. If there is nothing to do, the function must do
382  * nothing and not return an error. If more steps are or may be
383  * possible, it must use ff_filter_set_ready() to schedule another
384  * activation.
385  */
386  int (*activate)(AVFilterContext *ctx);
387 } AVFilter;
388 
389 /**
390  * Get the number of elements in an AVFilter's inputs or outputs array.
391  */
392 unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
393 
394 /**
395  * Process multiple parts of the frame concurrently.
396  */
397 #define AVFILTER_THREAD_SLICE (1 << 0)
398 
399 typedef struct AVFilterInternal AVFilterInternal;
400 
401 /** An instance of a filter */
403  const AVClass *av_class; ///< needed for av_log() and filters common options
404 
405  const AVFilter *filter; ///< the AVFilter of which this is an instance
406 
407  char *name; ///< name of this filter instance
408 
409  AVFilterPad *input_pads; ///< array of input pads
410  AVFilterLink **inputs; ///< array of pointers to input links
411  unsigned nb_inputs; ///< number of input pads
412 
413  AVFilterPad *output_pads; ///< array of output pads
414  AVFilterLink **outputs; ///< array of pointers to output links
415  unsigned nb_outputs; ///< number of output pads
416 
417  void *priv; ///< private data for use by the filter
418 
419  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
420 
421  /**
422  * Type of multithreading being allowed/used. A combination of
423  * AVFILTER_THREAD_* flags.
424  *
425  * May be set by the caller before initializing the filter to forbid some
426  * or all kinds of multithreading for this filter. The default is allowing
427  * everything.
428  *
429  * When the filter is initialized, this field is combined using bit AND with
430  * AVFilterGraph.thread_type to get the final mask used for determining
431  * allowed threading types. I.e. a threading type needs to be set in both
432  * to be allowed.
433  *
434  * After the filter is initialized, libavfilter sets this field to the
435  * threading type that is actually used (0 for no multithreading).
436  */
438 
439  /**
440  * An opaque struct for libavfilter internal use.
441  */
442  AVFilterInternal *internal;
443 
444  struct AVFilterCommand *command_queue;
445 
446  char *enable_str; ///< enable expression string
447  void *enable; ///< parsed expression (AVExpr*)
448  double *var_values; ///< variable values for the enable expression
449  int is_disabled; ///< the enabled state from the last expression evaluation
450 
451  /**
452  * For filters which will create hardware frames, sets the device the
453  * filter should create them in. All other filters will ignore this field:
454  * in particular, a filter which consumes or processes hardware frames will
455  * instead use the hw_frames_ctx field in AVFilterLink to carry the
456  * hardware context information.
457  */
459 
460  /**
461  * Max number of threads allowed in this filter instance.
462  * If <= 0, its value is ignored.
463  * Overrides global number of threads set per filter graph.
464  */
466 
467  /**
468  * Ready status of the filter.
469  * A non-0 value means that the filter needs activating;
470  * a higher value suggests a more urgent activation.
471  */
472  unsigned ready;
473 
474  /**
475  * Sets the number of extra hardware frames which the filter will
476  * allocate on its output links for use in following filters or by
477  * the caller.
478  *
479  * Some hardware filters require all frames that they will use for
480  * output to be defined in advance before filtering starts. For such
481  * filters, any hardware frame pools used for output must therefore be
482  * of fixed size. The extra frames set here are on top of any number
483  * that the filter needs internally in order to operate normally.
484  *
485  * This field must be set before the graph containing this filter is
486  * configured.
487  */
489 };
490 
491 /**
492  * Lists of formats / etc. supported by an end of a link.
493  *
494  * This structure is directly part of AVFilterLink, in two copies:
495  * one for the source filter, one for the destination filter.
496 
497  * These lists are used for negotiating the format to actually be used,
498  * which will be loaded into the format and channel_layout members of
499  * AVFilterLink, when chosen.
500  */
501 typedef struct AVFilterFormatsConfig {
502 
503  /**
504  * List of supported formats (pixel or sample).
505  */
507 
508  /**
509  * Lists of supported sample rates, only for audio.
510  */
512 
513  /**
514  * Lists of supported channel layouts, only for audio.
515  */
517 
519 
520 /**
521  * A link between two filters. This contains pointers to the source and
522  * destination filters between which this link exists, and the indexes of
523  * the pads involved. In addition, this link also contains the parameters
524  * which have been negotiated and agreed upon between the filter, such as
525  * image dimensions, format, etc.
526  *
527  * Applications must not normally access the link structure directly.
528  * Use the buffersrc and buffersink API instead.
529  * In the future, access to the header may be reserved for filters
530  * implementation.
531  */
532 struct AVFilterLink {
533  AVFilterContext *src; ///< source filter
534  AVFilterPad *srcpad; ///< output pad on the source filter
535 
536  AVFilterContext *dst; ///< dest filter
537  AVFilterPad *dstpad; ///< input pad on the dest filter
538 
539  enum AVMediaType type; ///< filter media type
540 
541  /* These parameters apply only to video */
542  int w; ///< agreed upon image width
543  int h; ///< agreed upon image height
544  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
545  /* These parameters apply only to audio */
546  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
547  int sample_rate; ///< samples per second
548 
549  int format; ///< agreed upon media format
550 
551  /**
552  * Define the time base used by the PTS of the frames/samples
553  * which will pass through this link.
554  * During the configuration stage, each filter is supposed to
555  * change only the output timebase, while the timebase of the
556  * input link is assumed to be an unchangeable property.
557  */
559 
560  /*****************************************************************
561  * All fields below this line are not part of the public API. They
562  * may not be used outside of libavfilter and can be changed and
563  * removed at will.
564  * New public fields should be added right above.
565  *****************************************************************
566  */
567 
568  /**
569  * Lists of supported formats / etc. supported by the input filter.
570  */
572 
573  /**
574  * Lists of supported formats / etc. supported by the output filter.
575  */
577 
578  /** stage of the initialization of the link properties (dimensions, etc) */
579  enum {
580  AVLINK_UNINIT = 0, ///< not started
581  AVLINK_STARTINIT, ///< started, but incomplete
582  AVLINK_INIT ///< complete
584 
585  /**
586  * Graph the filter belongs to.
587  */
589 
590  /**
591  * Current timestamp of the link, as defined by the most recent
592  * frame(s), in link time_base units.
593  */
594  int64_t current_pts;
595 
596  /**
597  * Current timestamp of the link, as defined by the most recent
598  * frame(s), in AV_TIME_BASE units.
599  */
600  int64_t current_pts_us;
601 
602  /**
603  * Index in the age array.
604  */
606 
607  /**
608  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
609  * if left to 0/0, will be automatically copied from the first input
610  * of the source filter if it exists.
611  *
612  * Sources should set it to the best estimation of the real frame rate.
613  * If the source frame rate is unknown or variable, set this to 1/0.
614  * Filters should update it if necessary depending on their function.
615  * Sinks can use it to set a default output frame rate.
616  * It is similar to the r_frame_rate field in AVStream.
617  */
619 
620  /**
621  * Minimum number of samples to filter at once. If filter_frame() is
622  * called with fewer samples, it will accumulate them in fifo.
623  * This field and the related ones must not be changed after filtering
624  * has started.
625  * If 0, all related fields are ignored.
626  */
628 
629  /**
630  * Maximum number of samples to filter at once. If filter_frame() is
631  * called with more samples, it will split them.
632  */
634 
635  /**
636  * Number of channels.
637  */
638  int channels;
639 
640  /**
641  * Number of past frames sent through the link.
642  */
644 
645  /**
646  * Number of past samples sent through the link.
647  */
649 
650  /**
651  * A pointer to a FFFramePool struct.
652  */
653  void *frame_pool;
654 
655  /**
656  * True if a frame is currently wanted on the output of this filter.
657  * Set when ff_request_frame() is called by the output,
658  * cleared when a frame is filtered.
659  */
661 
662  /**
663  * For hwaccel pixel formats, this should be a reference to the
664  * AVHWFramesContext describing the frames.
665  */
667 
668 #ifndef FF_INTERNAL_FIELDS
669 
670  /**
671  * Internal structure members.
672  * The fields below this limit are internal for libavfilter's use
673  * and must in no way be accessed by applications.
674  */
675  char reserved[0xF000];
676 
677 #else /* FF_INTERNAL_FIELDS */
678 
679  /**
680  * Queue of frames waiting to be filtered.
681  */
682  FFFrameQueue fifo;
683 
684  /**
685  * If set, the source filter can not generate a frame as is.
686  * The goal is to avoid repeatedly calling the request_frame() method on
687  * the same link.
688  */
689  int frame_blocked_in;
690 
691  /**
692  * Link input status.
693  * If not zero, all attempts of filter_frame will fail with the
694  * corresponding code.
695  */
696  int status_in;
697 
698  /**
699  * Timestamp of the input status change.
700  */
701  int64_t status_in_pts;
702 
703  /**
704  * Link output status.
705  * If not zero, all attempts of request_frame will fail with the
706  * corresponding code.
707  */
708  int status_out;
709 
710 #endif /* FF_INTERNAL_FIELDS */
711 
712 };
713 
714 /**
715  * Link two filters together.
716  *
717  * @param src the source filter
718  * @param srcpad index of the output pad on the source filter
719  * @param dst the destination filter
720  * @param dstpad index of the input pad on the destination filter
721  * @return zero on success
722  */
723 int avfilter_link(AVFilterContext *src, unsigned srcpad,
724  AVFilterContext *dst, unsigned dstpad);
725 
726 /**
727  * Free the link in *link, and set its pointer to NULL.
728  */
730 
731 /**
732  * Negotiate the media format, dimensions, etc of all inputs to a filter.
733  *
734  * @param filter the filter to negotiate the properties for its inputs
735  * @return zero on successful negotiation
736  */
738 
739 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
740 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
741 
742 /**
743  * Make the filter instance process a command.
744  * It is recommended to use avfilter_graph_send_command().
745  */
746 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
747 
748 /**
749  * Iterate over all registered filters.
750  *
751  * @param opaque a pointer where libavfilter will store the iteration state. Must
752  * point to NULL to start the iteration.
753  *
754  * @return the next registered filter or NULL when the iteration is
755  * finished
756  */
758 
759 /**
760  * Get a filter definition matching the given name.
761  *
762  * @param name the filter name to find
763  * @return the filter definition, if any matching one is registered.
764  * NULL if none found.
765  */
766 const AVFilter *avfilter_get_by_name(const char *name);
767 
768 
769 /**
770  * Initialize a filter with the supplied parameters.
771  *
772  * @param ctx uninitialized filter context to initialize
773  * @param args Options to initialize the filter with. This must be a
774  * ':'-separated list of options in the 'key=value' form.
775  * May be NULL if the options have been set directly using the
776  * AVOptions API or there are no options that need to be set.
777  * @return 0 on success, a negative AVERROR on failure
778  */
779 int avfilter_init_str(AVFilterContext *ctx, const char *args);
780 
781 /**
782  * Initialize a filter with the supplied dictionary of options.
783  *
784  * @param ctx uninitialized filter context to initialize
785  * @param options An AVDictionary filled with options for this filter. On
786  * return this parameter will be destroyed and replaced with
787  * a dict containing options that were not found. This dictionary
788  * must be freed by the caller.
789  * May be NULL, then this function is equivalent to
790  * avfilter_init_str() with the second parameter set to NULL.
791  * @return 0 on success, a negative AVERROR on failure
792  *
793  * @note This function and avfilter_init_str() do essentially the same thing,
794  * the difference is in manner in which the options are passed. It is up to the
795  * calling code to choose whichever is more preferable. The two functions also
796  * behave differently when some of the provided options are not declared as
797  * supported by the filter. In such a case, avfilter_init_str() will fail, but
798  * this function will leave those extra options in the options AVDictionary and
799  * continue as usual.
800  */
802 
803 /**
804  * Free a filter context. This will also remove the filter from its
805  * filtergraph's list of filters.
806  *
807  * @param filter the filter to free
808  */
810 
811 /**
812  * Insert a filter in the middle of an existing link.
813  *
814  * @param link the link into which the filter should be inserted
815  * @param filt the filter to be inserted
816  * @param filt_srcpad_idx the input pad on the filter to connect
817  * @param filt_dstpad_idx the output pad on the filter to connect
818  * @return zero on success
819  */
821  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
822 
823 /**
824  * @return AVClass for AVFilterContext.
825  *
826  * @see av_opt_find().
827  */
829 
831 
832 /**
833  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
834  * executed multiple times, possibly in parallel.
835  *
836  * @param ctx the filter context the job belongs to
837  * @param arg an opaque parameter passed through from @ref
838  * AVFilterGraph.execute
839  * @param jobnr the index of the job being executed
840  * @param nb_jobs the total number of jobs
841  *
842  * @return 0 on success, a negative AVERROR on error
843  */
844 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
845 
846 /**
847  * A function executing multiple jobs, possibly in parallel.
848  *
849  * @param ctx the filter context to which the jobs belong
850  * @param func the function to be called multiple times
851  * @param arg the argument to be passed to func
852  * @param ret a nb_jobs-sized array to be filled with return values from each
853  * invocation of func
854  * @param nb_jobs the number of jobs to execute
855  *
856  * @return 0 on success, a negative AVERROR on error
857  */
859  void *arg, int *ret, int nb_jobs);
860 
861 typedef struct AVFilterGraph {
864  unsigned nb_filters;
865 
866  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
867 
868  /**
869  * Type of multithreading allowed for filters in this graph. A combination
870  * of AVFILTER_THREAD_* flags.
871  *
872  * May be set by the caller at any point, the setting will apply to all
873  * filters initialized after that. The default is allowing everything.
874  *
875  * When a filter in this graph is initialized, this field is combined using
876  * bit AND with AVFilterContext.thread_type to get the final mask used for
877  * determining allowed threading types. I.e. a threading type needs to be
878  * set in both to be allowed.
879  */
881 
882  /**
883  * Maximum number of threads used by filters in this graph. May be set by
884  * the caller before adding any filters to the filtergraph. Zero (the
885  * default) means that the number of threads is determined automatically.
886  */
888 
889  /**
890  * Opaque object for libavfilter internal use.
891  */
893 
894  /**
895  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
896  * be used from callbacks like @ref AVFilterGraph.execute.
897  * Libavfilter will not touch this field in any way.
898  */
899  void *opaque;
900 
901  /**
902  * This callback may be set by the caller immediately after allocating the
903  * graph and before adding any filters to it, to provide a custom
904  * multithreading implementation.
905  *
906  * If set, filters with slice threading capability will call this callback
907  * to execute multiple jobs in parallel.
908  *
909  * If this field is left unset, libavfilter will use its internal
910  * implementation, which may or may not be multithreaded depending on the
911  * platform and build options.
912  */
914 
915  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
916 
917  /**
918  * Private fields
919  *
920  * The following fields are for internal use only.
921  * Their type, offset, number and semantic can change without notice.
922  */
923 
926 
928 } AVFilterGraph;
929 
930 /**
931  * Allocate a filter graph.
932  *
933  * @return the allocated filter graph on success or NULL.
934  */
936 
937 /**
938  * Create a new filter instance in a filter graph.
939  *
940  * @param graph graph in which the new filter will be used
941  * @param filter the filter to create an instance of
942  * @param name Name to give to the new instance (will be copied to
943  * AVFilterContext.name). This may be used by the caller to identify
944  * different filters, libavfilter itself assigns no semantics to
945  * this parameter. May be NULL.
946  *
947  * @return the context of the newly created filter instance (note that it is
948  * also retrievable directly through AVFilterGraph.filters or with
949  * avfilter_graph_get_filter()) on success or NULL on failure.
950  */
952  const AVFilter *filter,
953  const char *name);
954 
955 /**
956  * Get a filter instance identified by instance name from graph.
957  *
958  * @param graph filter graph to search through.
959  * @param name filter instance name (should be unique in the graph).
960  * @return the pointer to the found filter instance or NULL if it
961  * cannot be found.
962  */
964 
965 /**
966  * Create and add a filter instance into an existing graph.
967  * The filter instance is created from the filter filt and inited
968  * with the parameter args. opaque is currently ignored.
969  *
970  * In case of success put in *filt_ctx the pointer to the created
971  * filter instance, otherwise set *filt_ctx to NULL.
972  *
973  * @param name the instance name to give to the created filter instance
974  * @param graph_ctx the filter graph
975  * @return a negative AVERROR error code in case of failure, a non
976  * negative value otherwise
977  */
979  const char *name, const char *args, void *opaque,
980  AVFilterGraph *graph_ctx);
981 
982 /**
983  * Enable or disable automatic format conversion inside the graph.
984  *
985  * Note that format conversion can still happen inside explicitly inserted
986  * scale and aresample filters.
987  *
988  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
989  */
990 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags);
991 
992 enum {
993  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
994  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
995 };
996 
997 /**
998  * Check validity and configure all the links and formats in the graph.
999  *
1000  * @param graphctx the filter graph
1001  * @param log_ctx context used for logging
1002  * @return >= 0 in case of success, a negative AVERROR code otherwise
1003  */
1004 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1005 
1006 /**
1007  * Free a graph, destroy its links, and set *graph to NULL.
1008  * If *graph is NULL, do nothing.
1009  */
1011 
1012 /**
1013  * A linked-list of the inputs/outputs of the filter chain.
1014  *
1015  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1016  * where it is used to communicate open (unlinked) inputs and outputs from and
1017  * to the caller.
1018  * This struct specifies, per each not connected pad contained in the graph, the
1019  * filter context and the pad index required for establishing a link.
1020  */
1021 typedef struct AVFilterInOut {
1022  /** unique name for this input/output in the list */
1023  char *name;
1024 
1025  /** filter context associated to this input/output */
1027 
1028  /** index of the filt_ctx pad to use for linking */
1029  int pad_idx;
1030 
1031  /** next input/input in the list, NULL if this is the last */
1033 } AVFilterInOut;
1034 
1035 /**
1036  * Allocate a single AVFilterInOut entry.
1037  * Must be freed with avfilter_inout_free().
1038  * @return allocated AVFilterInOut on success, NULL on failure.
1039  */
1041 
1042 /**
1043  * Free the supplied list of AVFilterInOut and set *inout to NULL.
1044  * If *inout is NULL, do nothing.
1045  */
1047 
1048 /**
1049  * Add a graph described by a string to a graph.
1050  *
1051  * @note The caller must provide the lists of inputs and outputs,
1052  * which therefore must be known before calling the function.
1053  *
1054  * @note The inputs parameter describes inputs of the already existing
1055  * part of the graph; i.e. from the point of view of the newly created
1056  * part, they are outputs. Similarly the outputs parameter describes
1057  * outputs of the already existing filters, which are provided as
1058  * inputs to the parsed filters.
1059  *
1060  * @param graph the filter graph where to link the parsed graph context
1061  * @param filters string to be parsed
1062  * @param inputs linked list to the inputs of the graph
1063  * @param outputs linked list to the outputs of the graph
1064  * @return zero on success, a negative AVERROR code on error
1065  */
1066 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1067  AVFilterInOut *inputs, AVFilterInOut *outputs,
1068  void *log_ctx);
1069 
1070 /**
1071  * Add a graph described by a string to a graph.
1072  *
1073  * In the graph filters description, if the input label of the first
1074  * filter is not specified, "in" is assumed; if the output label of
1075  * the last filter is not specified, "out" is assumed.
1076  *
1077  * @param graph the filter graph where to link the parsed graph context
1078  * @param filters string to be parsed
1079  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1080  * If non-NULL, *inputs is updated to contain the list of open inputs
1081  * after the parsing, should be freed with avfilter_inout_free().
1082  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1083  * If non-NULL, *outputs is updated to contain the list of open outputs
1084  * after the parsing, should be freed with avfilter_inout_free().
1085  * @return non negative on success, a negative AVERROR code on error
1086  */
1087 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1088  AVFilterInOut **inputs, AVFilterInOut **outputs,
1089  void *log_ctx);
1090 
1091 /**
1092  * Add a graph described by a string to a graph.
1093  *
1094  * @param[in] graph the filter graph where to link the parsed graph context
1095  * @param[in] filters string to be parsed
1096  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1097  * parsed graph will be returned here. It is to be freed
1098  * by the caller using avfilter_inout_free().
1099  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1100  * parsed graph will be returned here. It is to be freed by the
1101  * caller using avfilter_inout_free().
1102  * @return zero on success, a negative AVERROR code on error
1103  *
1104  * @note This function returns the inputs and outputs that are left
1105  * unlinked after parsing the graph and the caller then deals with
1106  * them.
1107  * @note This function makes no reference whatsoever to already
1108  * existing parts of the graph and the inputs parameter will on return
1109  * contain inputs of the newly parsed part of the graph. Analogously
1110  * the outputs parameter will contain outputs of the newly created
1111  * filters.
1112  */
1113 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1114  AVFilterInOut **inputs,
1115  AVFilterInOut **outputs);
1116 
1117 /**
1118  * Send a command to one or more filter instances.
1119  *
1120  * @param graph the filter graph
1121  * @param target the filter(s) to which the command should be sent
1122  * "all" sends to all filters
1123  * otherwise it can be a filter or filter instance name
1124  * which will send the command to all matching filters.
1125  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1126  * @param arg the argument for the command
1127  * @param res a buffer with size res_size where the filter(s) can return a response.
1128  *
1129  * @returns >=0 on success otherwise an error code.
1130  * AVERROR(ENOSYS) on unsupported commands
1131  */
1132 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1133 
1134 /**
1135  * Queue a command for one or more filter instances.
1136  *
1137  * @param graph the filter graph
1138  * @param target the filter(s) to which the command should be sent
1139  * "all" sends to all filters
1140  * otherwise it can be a filter or filter instance name
1141  * which will send the command to all matching filters.
1142  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1143  * @param arg the argument for the command
1144  * @param ts time at which the command should be sent to the filter
1145  *
1146  * @note As this executes commands after this function returns, no return code
1147  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1148  */
1149 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1150 
1151 
1152 /**
1153  * Dump a graph into a human-readable string representation.
1154  *
1155  * @param graph the graph to dump
1156  * @param options formatting options; currently ignored
1157  * @return a string, or NULL in case of memory allocation failure;
1158  * the string must be freed using av_free
1159  */
1160 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1161 
1162 /**
1163  * Request a frame on the oldest sink link.
1164  *
1165  * If the request returns AVERROR_EOF, try the next.
1166  *
1167  * Note that this function is not meant to be the sole scheduling mechanism
1168  * of a filtergraph, only a convenience function to help drain a filtergraph
1169  * in a balanced way under normal circumstances.
1170  *
1171  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1172  * some of the sinks during the process.
1173  * When there are multiple sink links, in case the requested link
1174  * returns an EOF, this may cause a filter to flush pending frames
1175  * which are sent to another sink link, although unrequested.
1176  *
1177  * @return the return value of ff_request_frame(),
1178  * or AVERROR_EOF if all links returned AVERROR_EOF
1179  */
1181 
1182 /**
1183  * @}
1184  */
1185 
1186 #endif /* AVFILTER_AVFILTER_H */
Macro definitions for various function/variable attributes.
#define attribute_deprecated
Definition: attributes.h:100
Convenience header that includes libavutil's core.
refcounted data buffer API
Public dictionary API.
reference-counted frame API
struct AVFilterPad AVFilterPad
Definition: avfilter.h:69
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt, unsigned filt_srcpad_idx, unsigned filt_dstpad_idx)
Insert a filter in the middle of an existing link.
void avfilter_free(AVFilterContext *filter)
Free a filter context.
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
attribute_deprecated int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in an AVFilter's inputs or outputs array.
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts)
Queue a command for one or more filter instances.
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.
const AVClass * avfilter_get_class(void)
unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output)
Get the number of elements in an AVFilter's inputs or outputs array.
int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs)
Add a graph described by a string to a graph.
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags)
Make the filter instance process a command.
struct AVFilterInternal AVFilterInternal
Definition: avfilter.h:399
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
struct AVFilterChannelLayouts AVFilterChannelLayouts
Definition: avfilter.h:71
int() avfilter_action_func(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
A function pointer passed to the AVFilterGraph::execute callback to be executed multiple times,...
Definition: avfilter.h:844
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:858
struct AVFilterGraphInternal AVFilterGraphInternal
Definition: avfilter.h:830
AVFilterContext * avfilter_graph_alloc_filter(AVFilterGraph *graph, const AVFilter *filter, const char *name)
Create a new filter instance in a filter graph.
int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags)
Send a command to one or more filter instances.
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, AVFilterInOut *inputs, AVFilterInOut *outputs, void *log_ctx)
Add a graph described by a string to a graph.
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt, const char *name, const char *args, void *opaque, AVFilterGraph *graph_ctx)
Create and add a filter instance into an existing graph.
struct AVFilterFormats AVFilterFormats
Definition: avfilter.h:70
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
const char * avfilter_license(void)
Return the libavfilter license.
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
Enable or disable automatic format conversion inside the graph.
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
AVFilterContext * avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
Get a filter instance identified by instance name from graph.
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:994
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:993
struct AVDictionary AVDictionary
Definition: dict.h:84
AVMediaType
Definition: avutil.h:199
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
Libavfilter version macros.
pixel format definitions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
Utilties for rational number calculation.
A reference to a data buffer.
Definition: buffer.h:82
Describe the class of an AVClass context structure.
Definition: log.h:66
An instance of a filter.
Definition: avfilter.h:402
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:403
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:465
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:437
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:488
char * name
name of this filter instance
Definition: avfilter.h:407
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:447
unsigned nb_inputs
number of input pads
Definition: avfilter.h:411
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:410
char * enable_str
enable expression string
Definition: avfilter.h:446
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:405
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:419
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:409
void * priv
private data for use by the filter
Definition: avfilter.h:417
unsigned nb_outputs
number of output pads
Definition: avfilter.h:415
unsigned ready
Ready status of the filter.
Definition: avfilter.h:472
struct AVFilterCommand * command_queue
Definition: avfilter.h:444
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:413
double * var_values
variable values for the enable expression
Definition: avfilter.h:448
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:449
AVBufferRef * hw_device_ctx
For filters which will create hardware frames, sets the device the filter should create them in.
Definition: avfilter.h:458
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:414
Lists of formats / etc.
Definition: avfilter.h:501
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition: avfilter.h:506
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:516
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:511
unsigned nb_filters
Definition: avfilter.h:864
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:924
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:866
AVFilterContext ** filters
Definition: avfilter.h:863
void * opaque
Opaque user data.
Definition: avfilter.h:899
char * aresample_swr_opts
swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
Definition: avfilter.h:915
unsigned disable_auto_convert
Definition: avfilter.h:927
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:880
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:913
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:887
const AVClass * av_class
Definition: avfilter.h:862
int sink_links_count
Definition: avfilter.h:925
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1021
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1026
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:1029
char * name
unique name for this input/output in the list
Definition: avfilter.h:1023
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:1032
Filter definition.
Definition: avfilter.h:165
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:222
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:372
const char * name
Filter name.
Definition: avfilter.h:169
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:353
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:284
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:296
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:323
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:209
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:233
union AVFilter::@1 formats
The state of the following union is determined by formats_state.
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:248
enum AVSampleFormat * samples_list
Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE and restricted to filters that only have AVM...
Definition: avfilter.h:345
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:358
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:204
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:227
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:356
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:271
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:194
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:185
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:349
enum AVPixelFormat * pixels_list
A pointer to an array of admissible pixel formats delimited by AV_PIX_FMT_NONE.
Definition: avfilter.h:334
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:386
const char * description
A description of the filter.
Definition: avfilter.h:176
Rational number (pair of numerator and denominator).
Definition: rational.h:58