FFmpeg
avfilter.h
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1 /*
2  * filter layer
3  * Copyright (c) 2007 Bobby Bingham
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVFILTER_AVFILTER_H
23 #define AVFILTER_AVFILTER_H
24 
25 /**
26  * @file
27  * @ingroup lavfi
28  * Main libavfilter public API header
29  */
30 
31 /**
32  * @defgroup lavfi libavfilter
33  * Graph-based frame editing library.
34  *
35  * @{
36  */
37 
38 #include <stddef.h>
39 
40 #include "libavutil/attributes.h"
41 #include "libavutil/avutil.h"
42 #include "libavutil/buffer.h"
43 #include "libavutil/dict.h"
44 #include "libavutil/frame.h"
45 #include "libavutil/log.h"
46 #include "libavutil/samplefmt.h"
47 #include "libavutil/pixfmt.h"
48 #include "libavutil/rational.h"
49 
50 #include "libavfilter/version.h"
51 
52 /**
53  * Return the LIBAVFILTER_VERSION_INT constant.
54  */
55 unsigned avfilter_version(void);
56 
57 /**
58  * Return the libavfilter build-time configuration.
59  */
60 const char *avfilter_configuration(void);
61 
62 /**
63  * Return the libavfilter license.
64  */
65 const char *avfilter_license(void);
66 
67 typedef struct AVFilterContext AVFilterContext;
68 typedef struct AVFilterLink AVFilterLink;
69 typedef struct AVFilterPad AVFilterPad;
70 typedef struct AVFilterFormats AVFilterFormats;
72 
73 #if FF_API_PAD_COUNT
74 /**
75  * Get the number of elements in an AVFilter's inputs or outputs array.
76  *
77  * @deprecated Use avfilter_filter_pad_count() instead.
78  */
80 int avfilter_pad_count(const AVFilterPad *pads);
81 #endif
82 
83 /**
84  * Get the name of an AVFilterPad.
85  *
86  * @param pads an array of AVFilterPads
87  * @param pad_idx index of the pad in the array; it is the caller's
88  * responsibility to ensure the index is valid
89  *
90  * @return name of the pad_idx'th pad in pads
91  */
92 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
93 
94 /**
95  * Get the type of an AVFilterPad.
96  *
97  * @param pads an array of AVFilterPads
98  * @param pad_idx index of the pad in the array; it is the caller's
99  * responsibility to ensure the index is valid
100  *
101  * @return type of the pad_idx'th pad in pads
102  */
103 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
104 
105 /**
106  * The number of the filter inputs is not determined just by AVFilter.inputs.
107  * The filter might add additional inputs during initialization depending on the
108  * options supplied to it.
109  */
110 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
111 /**
112  * The number of the filter outputs is not determined just by AVFilter.outputs.
113  * The filter might add additional outputs during initialization depending on
114  * the options supplied to it.
115  */
116 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
117 /**
118  * The filter supports multithreading by splitting frames into multiple parts
119  * and processing them concurrently.
120  */
121 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
122 /**
123  * 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  */
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  */
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  */
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  */
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  */
350  /**
351  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
352  */
354  } formats;
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  */
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 
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
583  } init_state;
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  */
757 const AVFilter *av_filter_iterate(void **opaque);
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  */
828 const AVClass *avfilter_get_class(void);
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  */
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  */
1046 void avfilter_inout_free(AVFilterInOut **inout);
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  */
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  */
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  */
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 */
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:913
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:85
AVFilterContext::nb_threads
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:465
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:511
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
avfilter_filter_pad_count
unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output)
Get the number of elements in an AVFilter's inputs or outputs array.
Definition: avfilter.c:594
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:887
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:972
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:516
AVFilter::pixels_list
enum AVPixelFormat * pixels_list
A pointer to an array of admissible pixel formats delimited by AV_PIX_FMT_NONE.
Definition: avfilter.h:334
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:204
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:844
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:448
AVFilter::pix_fmt
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:349
rational.h
AVFilterContext::is_disabled
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:449
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:372
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:1032
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:415
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:993
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:403
AVFilterGraph::disable_auto_convert
unsigned disable_auto_convert
Definition: avfilter.h:927
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:458
AVFilterGraphInternal
Definition: internal.h:133
filter
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:228
AVDictionary
Definition: dict.c:30
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:413
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:169
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:994
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:121
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
avfilter_graph_create_filter
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt, const char *name, const char *args, void *opaque, AVFilterGraph *graph_ctx)
Create and add a filter instance into an existing graph.
Definition: avfiltergraph.c:140
avfilter_graph_alloc_filter
AVFilterContext * avfilter_graph_alloc_filter(AVFilterGraph *graph, const AVFilter *filter, const char *name)
Create a new filter instance in a filter graph.
Definition: avfiltergraph.c:167
graph
ofilter graph
Definition: ffmpeg_filter.c:171
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:417
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:419
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:446
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:84
AVFilter::formats_state
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:233
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:253
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:564
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:488
avfilter_config_links
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:290
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:899
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:358
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
Definition: avfilter.c:88
filters
#define filters(fmt, inverse, clip, i, c)
Definition: af_crystalizer.c:221
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:409
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:212
AVFilter::samples_list
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
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:552
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:172
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:209
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:915
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:386
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:575
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
AVFilterContext::thread_type
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:437
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:1156
AVFilter::outputs
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:194
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:863
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:410
AVFilterInternal
Definition: internal.h:139
src
#define src
Definition: vp8dsp.c:255
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:407
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:285
AVFilter::formats
union AVFilter::@197 formats
The state of the following union is determined by formats_state.
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1284
AVFilterGraph
Definition: avfilter.h:861
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_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:501
avfilter_pad_count
int avfilter_pad_count(const AVFilterPad *pads)
Definition: avfilter.c:574
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:1029
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:866
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:411
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:862
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:444
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1026
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:858
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:248
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:161
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:1204
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:176
avfilter_link_free
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
Definition: avfilter.c:200
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
attributes.h
AVFilter::nb_inputs
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:222
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:271
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:938
AVFilter::query_func
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:323
log.h
avfilter_graph_parse_ptr
int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs, void *log_ctx)
Add a graph described by a string to a graph.
Definition: graphparser.c:549
AVFilterCommand
Definition: internal.h:34
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVFilterGraph::thread_type
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:880
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:356
AVFilter
Filter definition.
Definition: avfilter.h:165
ret
ret
Definition: filter_design.txt:187
AVFilterGraph::sink_links
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:924
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:155
dict.h
AVFilter::nb_outputs
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:227
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:977
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:895
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:447
AVFilterContext
An instance of a filter.
Definition: avfilter.h:402
avfilter_graph_parse
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, AVFilterInOut *inputs, AVFilterInOut *outputs, void *log_ctx)
Add a graph described by a string to a graph.
Definition: graphparser.c:486
avutil.h
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVFilterFormatsConfig::formats
AVFilterFormats * formats
List of supported formats (pixel or sample).
Definition: avfilter.h:506
AVFilter::inputs
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:185
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:296
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:757
AVFilter::sample_fmt
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:353
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
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:1023
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:1174
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:864
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:405
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:284
int
int
Definition: ffmpeg_filter.c:153
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:1562
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1021
AVFilterGraph::sink_links_count
int sink_links_count
Definition: avfilter.h:925
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:472
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:414