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 /**
74  * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
75  * AVFilter.inputs/outputs).
76  */
77 int avfilter_pad_count(const AVFilterPad *pads);
78 
79 /**
80  * Get the name of an AVFilterPad.
81  *
82  * @param pads an array of AVFilterPads
83  * @param pad_idx index of the pad in the array; it is the caller's
84  * responsibility to ensure the index is valid
85  *
86  * @return name of the pad_idx'th pad in pads
87  */
88 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
89 
90 /**
91  * Get the type of an AVFilterPad.
92  *
93  * @param pads an array of AVFilterPads
94  * @param pad_idx index of the pad in the array; it is the caller's
95  * responsibility to ensure the index is valid
96  *
97  * @return type of the pad_idx'th pad in pads
98  */
99 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
100 
101 /**
102  * The number of the filter inputs is not determined just by AVFilter.inputs.
103  * The filter might add additional inputs during initialization depending on the
104  * options supplied to it.
105  */
106 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
107 /**
108  * The number of the filter outputs is not determined just by AVFilter.outputs.
109  * The filter might add additional outputs during initialization depending on
110  * the options supplied to it.
111  */
112 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
113 /**
114  * The filter supports multithreading by splitting frames into multiple parts
115  * and processing them concurrently.
116  */
117 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
118 /**
119  * Some filters support a generic "enable" expression option that can be used
120  * to enable or disable a filter in the timeline. Filters supporting this
121  * option have this flag set. When the enable expression is false, the default
122  * no-op filter_frame() function is called in place of the filter_frame()
123  * callback defined on each input pad, thus the frame is passed unchanged to
124  * the next filters.
125  */
126 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
127 /**
128  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
129  * have its filter_frame() callback(s) called as usual even when the enable
130  * expression is false. The filter will disable filtering within the
131  * filter_frame() callback(s) itself, for example executing code depending on
132  * the AVFilterContext->is_disabled value.
133  */
134 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
135 /**
136  * Handy mask to test whether the filter supports or no the timeline feature
137  * (internally or generically).
138  */
139 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
140 
141 /**
142  * Filter definition. This defines the pads a filter contains, and all the
143  * callback functions used to interact with the filter.
144  */
145 typedef struct AVFilter {
146  /**
147  * Filter name. Must be non-NULL and unique among filters.
148  */
149  const char *name;
150 
151  /**
152  * A description of the filter. May be NULL.
153  *
154  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
155  */
156  const char *description;
157 
158  /**
159  * List of inputs, terminated by a zeroed element.
160  *
161  * NULL if there are no (static) inputs. Instances of filters with
162  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
163  * this list.
164  */
166  /**
167  * List of outputs, terminated by a zeroed element.
168  *
169  * NULL if there are no (static) outputs. Instances of filters with
170  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
171  * this list.
172  */
174 
175  /**
176  * A class for the private data, used to declare filter private AVOptions.
177  * This field is NULL for filters that do not declare any options.
178  *
179  * If this field is non-NULL, the first member of the filter private data
180  * must be a pointer to AVClass, which will be set by libavfilter generic
181  * code to this class.
182  */
184 
185  /**
186  * A combination of AVFILTER_FLAG_*
187  */
188  int flags;
189 
190  /*****************************************************************
191  * All fields below this line are not part of the public API. They
192  * may not be used outside of libavfilter and can be changed and
193  * removed at will.
194  * New public fields should be added right above.
195  *****************************************************************
196  */
197 
198  /**
199  * Filter pre-initialization function
200  *
201  * This callback will be called immediately after the filter context is
202  * allocated, to allow allocating and initing sub-objects.
203  *
204  * If this callback is not NULL, the uninit callback will be called on
205  * allocation failure.
206  *
207  * @return 0 on success,
208  * AVERROR code on failure (but the code will be
209  * dropped and treated as ENOMEM by the calling code)
210  */
212 
213  /**
214  * Filter initialization function.
215  *
216  * This callback will be called only once during the filter lifetime, after
217  * all the options have been set, but before links between filters are
218  * established and format negotiation is done.
219  *
220  * Basic filter initialization should be done here. Filters with dynamic
221  * inputs and/or outputs should create those inputs/outputs here based on
222  * provided options. No more changes to this filter's inputs/outputs can be
223  * done after this callback.
224  *
225  * This callback must not assume that the filter links exist or frame
226  * parameters are known.
227  *
228  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
229  * initialization fails, so this callback does not have to clean up on
230  * failure.
231  *
232  * @return 0 on success, a negative AVERROR on failure
233  */
235 
236  /**
237  * Should be set instead of @ref AVFilter.init "init" by the filters that
238  * want to pass a dictionary of AVOptions to nested contexts that are
239  * allocated during init.
240  *
241  * On return, the options dict should be freed and replaced with one that
242  * contains all the options which could not be processed by this filter (or
243  * with NULL if all the options were processed).
244  *
245  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
246  */
248 
249  /**
250  * Filter uninitialization function.
251  *
252  * Called only once right before the filter is freed. Should deallocate any
253  * memory held by the filter, release any buffer references, etc. It does
254  * not need to deallocate the AVFilterContext.priv memory itself.
255  *
256  * This callback may be called even if @ref AVFilter.init "init" was not
257  * called or failed, so it must be prepared to handle such a situation.
258  */
260 
261  /**
262  * Query formats supported by the filter on its inputs and outputs.
263  *
264  * This callback is called after the filter is initialized (so the inputs
265  * and outputs are fixed), shortly before the format negotiation. This
266  * callback may be called more than once.
267  *
268  * This callback must set AVFilterLink.outcfg.formats on every input link and
269  * AVFilterLink.incfg.formats on every output link to a list of pixel/sample
270  * formats that the filter supports on that link. For audio links, this
271  * filter must also set @ref AVFilterLink.incfg.samplerates "in_samplerates" /
272  * @ref AVFilterLink.outcfg.samplerates "out_samplerates" and
273  * @ref AVFilterLink.incfg.channel_layouts "in_channel_layouts" /
274  * @ref AVFilterLink.outcfg.channel_layouts "out_channel_layouts" analogously.
275  *
276  * This callback may be NULL for filters with one input, in which case
277  * libavfilter assumes that it supports all input formats and preserves
278  * them on output.
279  *
280  * @return zero on success, a negative value corresponding to an
281  * AVERROR code otherwise
282  */
284 
285  int priv_size; ///< size of private data to allocate for the filter
286 
287  int flags_internal; ///< Additional flags for avfilter internal use only.
288 
289  /**
290  * Make the filter instance process a command.
291  *
292  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
293  * @param arg the argument for the command
294  * @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.
295  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
296  * time consuming then a filter should treat it like an unsupported command
297  *
298  * @returns >=0 on success otherwise an error code.
299  * AVERROR(ENOSYS) on unsupported commands
300  */
301  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
302 
303  /**
304  * Filter initialization function, alternative to the init()
305  * callback. Args contains the user-supplied parameters, opaque is
306  * used for providing binary data.
307  */
308  int (*init_opaque)(AVFilterContext *ctx, void *opaque);
309 
310  /**
311  * Filter activation function.
312  *
313  * Called when any processing is needed from the filter, instead of any
314  * filter_frame and request_frame on pads.
315  *
316  * The function must examine inlinks and outlinks and perform a single
317  * step of processing. If there is nothing to do, the function must do
318  * nothing and not return an error. If more steps are or may be
319  * possible, it must use ff_filter_set_ready() to schedule another
320  * activation.
321  */
323 } AVFilter;
324 
325 /**
326  * Process multiple parts of the frame concurrently.
327  */
328 #define AVFILTER_THREAD_SLICE (1 << 0)
329 
330 typedef struct AVFilterInternal AVFilterInternal;
331 
332 /** An instance of a filter */
334  const AVClass *av_class; ///< needed for av_log() and filters common options
335 
336  const AVFilter *filter; ///< the AVFilter of which this is an instance
337 
338  char *name; ///< name of this filter instance
339 
340  AVFilterPad *input_pads; ///< array of input pads
341  AVFilterLink **inputs; ///< array of pointers to input links
342  unsigned nb_inputs; ///< number of input pads
343 
344  AVFilterPad *output_pads; ///< array of output pads
345  AVFilterLink **outputs; ///< array of pointers to output links
346  unsigned nb_outputs; ///< number of output pads
347 
348  void *priv; ///< private data for use by the filter
349 
350  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
351 
352  /**
353  * Type of multithreading being allowed/used. A combination of
354  * AVFILTER_THREAD_* flags.
355  *
356  * May be set by the caller before initializing the filter to forbid some
357  * or all kinds of multithreading for this filter. The default is allowing
358  * everything.
359  *
360  * When the filter is initialized, this field is combined using bit AND with
361  * AVFilterGraph.thread_type to get the final mask used for determining
362  * allowed threading types. I.e. a threading type needs to be set in both
363  * to be allowed.
364  *
365  * After the filter is initialized, libavfilter sets this field to the
366  * threading type that is actually used (0 for no multithreading).
367  */
369 
370  /**
371  * An opaque struct for libavfilter internal use.
372  */
373  AVFilterInternal *internal;
374 
376 
377  char *enable_str; ///< enable expression string
378  void *enable; ///< parsed expression (AVExpr*)
379  double *var_values; ///< variable values for the enable expression
380  int is_disabled; ///< the enabled state from the last expression evaluation
381 
382  /**
383  * For filters which will create hardware frames, sets the device the
384  * filter should create them in. All other filters will ignore this field:
385  * in particular, a filter which consumes or processes hardware frames will
386  * instead use the hw_frames_ctx field in AVFilterLink to carry the
387  * hardware context information.
388  */
390 
391  /**
392  * Max number of threads allowed in this filter instance.
393  * If <= 0, its value is ignored.
394  * Overrides global number of threads set per filter graph.
395  */
397 
398  /**
399  * Ready status of the filter.
400  * A non-0 value means that the filter needs activating;
401  * a higher value suggests a more urgent activation.
402  */
403  unsigned ready;
404 
405  /**
406  * Sets the number of extra hardware frames which the filter will
407  * allocate on its output links for use in following filters or by
408  * the caller.
409  *
410  * Some hardware filters require all frames that they will use for
411  * output to be defined in advance before filtering starts. For such
412  * filters, any hardware frame pools used for output must therefore be
413  * of fixed size. The extra frames set here are on top of any number
414  * that the filter needs internally in order to operate normally.
415  *
416  * This field must be set before the graph containing this filter is
417  * configured.
418  */
420 };
421 
422 /**
423  * Lists of formats / etc. supported by an end of a link.
424  *
425  * This structure is directly part of AVFilterLink, in two copies:
426  * one for the source filter, one for the destination filter.
427 
428  * These lists are used for negotiating the format to actually be used,
429  * which will be loaded into the format and channel_layout members of
430  * AVFilterLink, when chosen.
431  */
432 typedef struct AVFilterFormatsConfig {
433 
434  /**
435  * List of supported formats (pixel or sample).
436  */
438 
439  /**
440  * Lists of supported sample rates, only for audio.
441  */
443 
444  /**
445  * Lists of supported channel layouts, only for audio.
446  */
448 
450 
451 /**
452  * A link between two filters. This contains pointers to the source and
453  * destination filters between which this link exists, and the indexes of
454  * the pads involved. In addition, this link also contains the parameters
455  * which have been negotiated and agreed upon between the filter, such as
456  * image dimensions, format, etc.
457  *
458  * Applications must not normally access the link structure directly.
459  * Use the buffersrc and buffersink API instead.
460  * In the future, access to the header may be reserved for filters
461  * implementation.
462  */
463 struct AVFilterLink {
464  AVFilterContext *src; ///< source filter
465  AVFilterPad *srcpad; ///< output pad on the source filter
466 
467  AVFilterContext *dst; ///< dest filter
468  AVFilterPad *dstpad; ///< input pad on the dest filter
469 
470  enum AVMediaType type; ///< filter media type
471 
472  /* These parameters apply only to video */
473  int w; ///< agreed upon image width
474  int h; ///< agreed upon image height
475  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
476  /* These parameters apply only to audio */
477  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
478  int sample_rate; ///< samples per second
479 
480  int format; ///< agreed upon media format
481 
482  /**
483  * Define the time base used by the PTS of the frames/samples
484  * which will pass through this link.
485  * During the configuration stage, each filter is supposed to
486  * change only the output timebase, while the timebase of the
487  * input link is assumed to be an unchangeable property.
488  */
490 
491  /*****************************************************************
492  * All fields below this line are not part of the public API. They
493  * may not be used outside of libavfilter and can be changed and
494  * removed at will.
495  * New public fields should be added right above.
496  *****************************************************************
497  */
498 
499  /**
500  * Lists of supported formats / etc. supported by the input filter.
501  */
503 
504  /**
505  * Lists of supported formats / etc. supported by the output filter.
506  */
508 
509  /** stage of the initialization of the link properties (dimensions, etc) */
510  enum {
511  AVLINK_UNINIT = 0, ///< not started
512  AVLINK_STARTINIT, ///< started, but incomplete
513  AVLINK_INIT ///< complete
514  } init_state;
515 
516  /**
517  * Graph the filter belongs to.
518  */
520 
521  /**
522  * Current timestamp of the link, as defined by the most recent
523  * frame(s), in link time_base units.
524  */
525  int64_t current_pts;
526 
527  /**
528  * Current timestamp of the link, as defined by the most recent
529  * frame(s), in AV_TIME_BASE units.
530  */
531  int64_t current_pts_us;
532 
533  /**
534  * Index in the age array.
535  */
537 
538  /**
539  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
540  * if left to 0/0, will be automatically copied from the first input
541  * of the source filter if it exists.
542  *
543  * Sources should set it to the best estimation of the real frame rate.
544  * If the source frame rate is unknown or variable, set this to 1/0.
545  * Filters should update it if necessary depending on their function.
546  * Sinks can use it to set a default output frame rate.
547  * It is similar to the r_frame_rate field in AVStream.
548  */
550 
551  /**
552  * Buffer partially filled with samples to achieve a fixed/minimum size.
553  */
555 
556  /**
557  * Size of the partial buffer to allocate.
558  * Must be between min_samples and max_samples.
559  */
561 
562  /**
563  * Minimum number of samples to filter at once. If filter_frame() is
564  * called with fewer samples, it will accumulate them in partial_buf.
565  * This field and the related ones must not be changed after filtering
566  * has started.
567  * If 0, all related fields are ignored.
568  */
570 
571  /**
572  * Maximum number of samples to filter at once. If filter_frame() is
573  * called with more samples, it will split them.
574  */
576 
577  /**
578  * Number of channels.
579  */
580  int channels;
581 
582  /**
583  * Number of past frames sent through the link.
584  */
586 
587  /**
588  * A pointer to a FFFramePool struct.
589  */
590  void *frame_pool;
591 
592  /**
593  * True if a frame is currently wanted on the output of this filter.
594  * Set when ff_request_frame() is called by the output,
595  * cleared when a frame is filtered.
596  */
598 
599  /**
600  * For hwaccel pixel formats, this should be a reference to the
601  * AVHWFramesContext describing the frames.
602  */
604 
605 #ifndef FF_INTERNAL_FIELDS
606 
607  /**
608  * Internal structure members.
609  * The fields below this limit are internal for libavfilter's use
610  * and must in no way be accessed by applications.
611  */
612  char reserved[0xF000];
613 
614 #else /* FF_INTERNAL_FIELDS */
615 
616  /**
617  * Queue of frames waiting to be filtered.
618  */
619  FFFrameQueue fifo;
620 
621  /**
622  * If set, the source filter can not generate a frame as is.
623  * The goal is to avoid repeatedly calling the request_frame() method on
624  * the same link.
625  */
626  int frame_blocked_in;
627 
628  /**
629  * Link input status.
630  * If not zero, all attempts of filter_frame will fail with the
631  * corresponding code.
632  */
633  int status_in;
634 
635  /**
636  * Timestamp of the input status change.
637  */
638  int64_t status_in_pts;
639 
640  /**
641  * Link output status.
642  * If not zero, all attempts of request_frame will fail with the
643  * corresponding code.
644  */
645  int status_out;
646 
647 #endif /* FF_INTERNAL_FIELDS */
648 
649 };
650 
651 /**
652  * Link two filters together.
653  *
654  * @param src the source filter
655  * @param srcpad index of the output pad on the source filter
656  * @param dst the destination filter
657  * @param dstpad index of the input pad on the destination filter
658  * @return zero on success
659  */
660 int avfilter_link(AVFilterContext *src, unsigned srcpad,
661  AVFilterContext *dst, unsigned dstpad);
662 
663 /**
664  * Free the link in *link, and set its pointer to NULL.
665  */
667 
668 /**
669  * Negotiate the media format, dimensions, etc of all inputs to a filter.
670  *
671  * @param filter the filter to negotiate the properties for its inputs
672  * @return zero on successful negotiation
673  */
675 
676 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
677 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
678 
679 /**
680  * Make the filter instance process a command.
681  * It is recommended to use avfilter_graph_send_command().
682  */
683 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
684 
685 /**
686  * Iterate over all registered filters.
687  *
688  * @param opaque a pointer where libavfilter will store the iteration state. Must
689  * point to NULL to start the iteration.
690  *
691  * @return the next registered filter or NULL when the iteration is
692  * finished
693  */
694 const AVFilter *av_filter_iterate(void **opaque);
695 
696 /**
697  * Get a filter definition matching the given name.
698  *
699  * @param name the filter name to find
700  * @return the filter definition, if any matching one is registered.
701  * NULL if none found.
702  */
703 const AVFilter *avfilter_get_by_name(const char *name);
704 
705 
706 /**
707  * Initialize a filter with the supplied parameters.
708  *
709  * @param ctx uninitialized filter context to initialize
710  * @param args Options to initialize the filter with. This must be a
711  * ':'-separated list of options in the 'key=value' form.
712  * May be NULL if the options have been set directly using the
713  * AVOptions API or there are no options that need to be set.
714  * @return 0 on success, a negative AVERROR on failure
715  */
716 int avfilter_init_str(AVFilterContext *ctx, const char *args);
717 
718 /**
719  * Initialize a filter with the supplied dictionary of options.
720  *
721  * @param ctx uninitialized filter context to initialize
722  * @param options An AVDictionary filled with options for this filter. On
723  * return this parameter will be destroyed and replaced with
724  * a dict containing options that were not found. This dictionary
725  * must be freed by the caller.
726  * May be NULL, then this function is equivalent to
727  * avfilter_init_str() with the second parameter set to NULL.
728  * @return 0 on success, a negative AVERROR on failure
729  *
730  * @note This function and avfilter_init_str() do essentially the same thing,
731  * the difference is in manner in which the options are passed. It is up to the
732  * calling code to choose whichever is more preferable. The two functions also
733  * behave differently when some of the provided options are not declared as
734  * supported by the filter. In such a case, avfilter_init_str() will fail, but
735  * this function will leave those extra options in the options AVDictionary and
736  * continue as usual.
737  */
739 
740 /**
741  * Free a filter context. This will also remove the filter from its
742  * filtergraph's list of filters.
743  *
744  * @param filter the filter to free
745  */
747 
748 /**
749  * Insert a filter in the middle of an existing link.
750  *
751  * @param link the link into which the filter should be inserted
752  * @param filt the filter to be inserted
753  * @param filt_srcpad_idx the input pad on the filter to connect
754  * @param filt_dstpad_idx the output pad on the filter to connect
755  * @return zero on success
756  */
758  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
759 
760 /**
761  * @return AVClass for AVFilterContext.
762  *
763  * @see av_opt_find().
764  */
765 const AVClass *avfilter_get_class(void);
766 
768 
769 /**
770  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
771  * executed multiple times, possibly in parallel.
772  *
773  * @param ctx the filter context the job belongs to
774  * @param arg an opaque parameter passed through from @ref
775  * AVFilterGraph.execute
776  * @param jobnr the index of the job being executed
777  * @param nb_jobs the total number of jobs
778  *
779  * @return 0 on success, a negative AVERROR on error
780  */
781 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
782 
783 /**
784  * A function executing multiple jobs, possibly in parallel.
785  *
786  * @param ctx the filter context to which the jobs belong
787  * @param func the function to be called multiple times
788  * @param arg the argument to be passed to func
789  * @param ret a nb_jobs-sized array to be filled with return values from each
790  * invocation of func
791  * @param nb_jobs the number of jobs to execute
792  *
793  * @return 0 on success, a negative AVERROR on error
794  */
796  void *arg, int *ret, int nb_jobs);
797 
798 typedef struct AVFilterGraph {
801  unsigned nb_filters;
802 
803  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
804 
805  /**
806  * Type of multithreading allowed for filters in this graph. A combination
807  * of AVFILTER_THREAD_* flags.
808  *
809  * May be set by the caller at any point, the setting will apply to all
810  * filters initialized after that. The default is allowing everything.
811  *
812  * When a filter in this graph is initialized, this field is combined using
813  * bit AND with AVFilterContext.thread_type to get the final mask used for
814  * determining allowed threading types. I.e. a threading type needs to be
815  * set in both to be allowed.
816  */
818 
819  /**
820  * Maximum number of threads used by filters in this graph. May be set by
821  * the caller before adding any filters to the filtergraph. Zero (the
822  * default) means that the number of threads is determined automatically.
823  */
825 
826  /**
827  * Opaque object for libavfilter internal use.
828  */
830 
831  /**
832  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
833  * be used from callbacks like @ref AVFilterGraph.execute.
834  * Libavfilter will not touch this field in any way.
835  */
836  void *opaque;
837 
838  /**
839  * This callback may be set by the caller immediately after allocating the
840  * graph and before adding any filters to it, to provide a custom
841  * multithreading implementation.
842  *
843  * If set, filters with slice threading capability will call this callback
844  * to execute multiple jobs in parallel.
845  *
846  * If this field is left unset, libavfilter will use its internal
847  * implementation, which may or may not be multithreaded depending on the
848  * platform and build options.
849  */
851 
852  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
853 
854  /**
855  * Private fields
856  *
857  * The following fields are for internal use only.
858  * Their type, offset, number and semantic can change without notice.
859  */
860 
863 
865 } AVFilterGraph;
866 
867 /**
868  * Allocate a filter graph.
869  *
870  * @return the allocated filter graph on success or NULL.
871  */
873 
874 /**
875  * Create a new filter instance in a filter graph.
876  *
877  * @param graph graph in which the new filter will be used
878  * @param filter the filter to create an instance of
879  * @param name Name to give to the new instance (will be copied to
880  * AVFilterContext.name). This may be used by the caller to identify
881  * different filters, libavfilter itself assigns no semantics to
882  * this parameter. May be NULL.
883  *
884  * @return the context of the newly created filter instance (note that it is
885  * also retrievable directly through AVFilterGraph.filters or with
886  * avfilter_graph_get_filter()) on success or NULL on failure.
887  */
889  const AVFilter *filter,
890  const char *name);
891 
892 /**
893  * Get a filter instance identified by instance name from graph.
894  *
895  * @param graph filter graph to search through.
896  * @param name filter instance name (should be unique in the graph).
897  * @return the pointer to the found filter instance or NULL if it
898  * cannot be found.
899  */
901 
902 /**
903  * Create and add a filter instance into an existing graph.
904  * The filter instance is created from the filter filt and inited
905  * with the parameter args. opaque is currently ignored.
906  *
907  * In case of success put in *filt_ctx the pointer to the created
908  * filter instance, otherwise set *filt_ctx to NULL.
909  *
910  * @param name the instance name to give to the created filter instance
911  * @param graph_ctx the filter graph
912  * @return a negative AVERROR error code in case of failure, a non
913  * negative value otherwise
914  */
916  const char *name, const char *args, void *opaque,
917  AVFilterGraph *graph_ctx);
918 
919 /**
920  * Enable or disable automatic format conversion inside the graph.
921  *
922  * Note that format conversion can still happen inside explicitly inserted
923  * scale and aresample filters.
924  *
925  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
926  */
928 
929 enum {
930  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
931  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
932 };
933 
934 /**
935  * Check validity and configure all the links and formats in the graph.
936  *
937  * @param graphctx the filter graph
938  * @param log_ctx context used for logging
939  * @return >= 0 in case of success, a negative AVERROR code otherwise
940  */
941 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
942 
943 /**
944  * Free a graph, destroy its links, and set *graph to NULL.
945  * If *graph is NULL, do nothing.
946  */
948 
949 /**
950  * A linked-list of the inputs/outputs of the filter chain.
951  *
952  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
953  * where it is used to communicate open (unlinked) inputs and outputs from and
954  * to the caller.
955  * This struct specifies, per each not connected pad contained in the graph, the
956  * filter context and the pad index required for establishing a link.
957  */
958 typedef struct AVFilterInOut {
959  /** unique name for this input/output in the list */
960  char *name;
961 
962  /** filter context associated to this input/output */
964 
965  /** index of the filt_ctx pad to use for linking */
966  int pad_idx;
967 
968  /** next input/input in the list, NULL if this is the last */
970 } AVFilterInOut;
971 
972 /**
973  * Allocate a single AVFilterInOut entry.
974  * Must be freed with avfilter_inout_free().
975  * @return allocated AVFilterInOut on success, NULL on failure.
976  */
978 
979 /**
980  * Free the supplied list of AVFilterInOut and set *inout to NULL.
981  * If *inout is NULL, do nothing.
982  */
983 void avfilter_inout_free(AVFilterInOut **inout);
984 
985 /**
986  * Add a graph described by a string to a graph.
987  *
988  * @note The caller must provide the lists of inputs and outputs,
989  * which therefore must be known before calling the function.
990  *
991  * @note The inputs parameter describes inputs of the already existing
992  * part of the graph; i.e. from the point of view of the newly created
993  * part, they are outputs. Similarly the outputs parameter describes
994  * outputs of the already existing filters, which are provided as
995  * inputs to the parsed filters.
996  *
997  * @param graph the filter graph where to link the parsed graph context
998  * @param filters string to be parsed
999  * @param inputs linked list to the inputs of the graph
1000  * @param outputs linked list to the outputs of the graph
1001  * @return zero on success, a negative AVERROR code on error
1002  */
1005  void *log_ctx);
1006 
1007 /**
1008  * Add a graph described by a string to a graph.
1009  *
1010  * In the graph filters description, if the input label of the first
1011  * filter is not specified, "in" is assumed; if the output label of
1012  * the last filter is not specified, "out" is assumed.
1013  *
1014  * @param graph the filter graph where to link the parsed graph context
1015  * @param filters string to be parsed
1016  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1017  * If non-NULL, *inputs is updated to contain the list of open inputs
1018  * after the parsing, should be freed with avfilter_inout_free().
1019  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1020  * If non-NULL, *outputs is updated to contain the list of open outputs
1021  * after the parsing, should be freed with avfilter_inout_free().
1022  * @return non negative on success, a negative AVERROR code on error
1023  */
1026  void *log_ctx);
1027 
1028 /**
1029  * Add a graph described by a string to a graph.
1030  *
1031  * @param[in] graph the filter graph where to link the parsed graph context
1032  * @param[in] filters string to be parsed
1033  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1034  * parsed graph will be returned here. It is to be freed
1035  * by the caller using avfilter_inout_free().
1036  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1037  * parsed graph will be returned here. It is to be freed by the
1038  * caller using avfilter_inout_free().
1039  * @return zero on success, a negative AVERROR code on error
1040  *
1041  * @note This function returns the inputs and outputs that are left
1042  * unlinked after parsing the graph and the caller then deals with
1043  * them.
1044  * @note This function makes no reference whatsoever to already
1045  * existing parts of the graph and the inputs parameter will on return
1046  * contain inputs of the newly parsed part of the graph. Analogously
1047  * the outputs parameter will contain outputs of the newly created
1048  * filters.
1049  */
1053 
1054 /**
1055  * Send a command to one or more filter instances.
1056  *
1057  * @param graph the filter graph
1058  * @param target the filter(s) to which the command should be sent
1059  * "all" sends to all filters
1060  * otherwise it can be a filter or filter instance name
1061  * which will send the command to all matching filters.
1062  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1063  * @param arg the argument for the command
1064  * @param res a buffer with size res_size where the filter(s) can return a response.
1065  *
1066  * @returns >=0 on success otherwise an error code.
1067  * AVERROR(ENOSYS) on unsupported commands
1068  */
1069 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1070 
1071 /**
1072  * Queue a command for one or more filter instances.
1073  *
1074  * @param graph the filter graph
1075  * @param target the filter(s) to which the command should be sent
1076  * "all" sends to all filters
1077  * otherwise it can be a filter or filter instance name
1078  * which will send the command to all matching filters.
1079  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1080  * @param arg the argument for the command
1081  * @param ts time at which the command should be sent to the filter
1082  *
1083  * @note As this executes commands after this function returns, no return code
1084  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1085  */
1086 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1087 
1088 
1089 /**
1090  * Dump a graph into a human-readable string representation.
1091  *
1092  * @param graph the graph to dump
1093  * @param options formatting options; currently ignored
1094  * @return a string, or NULL in case of memory allocation failure;
1095  * the string must be freed using av_free
1096  */
1097 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1098 
1099 /**
1100  * Request a frame on the oldest sink link.
1101  *
1102  * If the request returns AVERROR_EOF, try the next.
1103  *
1104  * Note that this function is not meant to be the sole scheduling mechanism
1105  * of a filtergraph, only a convenience function to help drain a filtergraph
1106  * in a balanced way under normal circumstances.
1107  *
1108  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1109  * some of the sinks during the process.
1110  * When there are multiple sink links, in case the requested link
1111  * returns an EOF, this may cause a filter to flush pending frames
1112  * which are sent to another sink link, although unrequested.
1113  *
1114  * @return the return value of ff_request_frame(),
1115  * or AVERROR_EOF if all links returned AVERROR_EOF
1116  */
1118 
1119 /**
1120  * @}
1121  */
1122 
1123 #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:850
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:86
AVFilterContext::nb_threads
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:396
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:442
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
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:824
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:932
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:447
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:183
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:781
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:379
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:380
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:301
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:969
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:346
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:334
AVFilterGraph::disable_auto_convert
unsigned disable_auto_convert
Definition: avfilter.h:864
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:389
AVFilterGraphInternal
Definition: internal.h:129
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:344
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:149
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:120
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:65
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:139
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:167
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:348
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:350
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:377
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:83
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:228
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:536
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:419
avfilter_config_links
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:265
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:836
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:287
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
Definition: avfilter.c:88
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:340
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:527
avfilter_pad_count
int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
Definition: avfilter.c:548
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:188
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:852
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:322
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:547
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
AVFilterContext::thread_type
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:368
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:1215
AVFilter::outputs
const AVFilterPad * outputs
List of outputs, terminated by a zeroed element.
Definition: avfilter.h:173
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:162
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:800
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:341
AVFilterInternal
Definition: internal.h:135
src
#define src
Definition: vp8dsp.c:255
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:338
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:287
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1343
AVFilterGraph
Definition: avfilter.h:798
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:432
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:966
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:803
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:342
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:799
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:375
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:930
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:963
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:795
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:211
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:135
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:1263
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:156
avfilter_link_free
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
Definition: avfilter.c:174
buffer.h
attributes.h
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:234
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:898
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:38
AVFilterGraph::thread_type
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:817
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:285
AVFilter
Filter definition.
Definition: avfilter.h:145
ret
ret
Definition: filter_design.txt:187
AVFilterGraph::sink_links
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:861
pixfmt.h
avfilter_configuration
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
Definition: avfilter.c:83
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:154
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:937
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:855
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:378
AVFilterContext
An instance of a filter.
Definition: avfilter.h:333
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
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:931
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:84
AVFilter::init_opaque
int(* init_opaque)(AVFilterContext *ctx, void *opaque)
Filter initialization function, alternative to the init() callback.
Definition: avfilter.h:308
AVFilterFormatsConfig::formats
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition: avfilter.h:437
AVFilter::inputs
const AVFilterPad * inputs
List of inputs, terminated by a zeroed element.
Definition: avfilter.h:165
AVFilter::query_formats
int(* query_formats)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:283
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:259
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:720
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
filters
ist filters[ist->nb_filters - 1]
Definition: ffmpeg_filter.c:191
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:960
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:1233
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:801
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:336
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:247
int
int
Definition: ffmpeg_filter.c:156
avfilter_version
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
Definition: avfilter.c:77
avfilter_get_class
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1530
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:958
AVFilterGraph::sink_links_count
int sink_links_count
Definition: avfilter.h:862
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:403
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:345