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 
51 #ifndef HAVE_AV_CONFIG_H
52 /* When included as part of the ffmpeg build, only include the major version
53  * to avoid unnecessary rebuilds. When included externally, keep including
54  * the full version information. */
55 #include "libavfilter/version.h"
56 #endif
57 
58 /**
59  * Return the LIBAVFILTER_VERSION_INT constant.
60  */
61 unsigned avfilter_version(void);
62 
63 /**
64  * Return the libavfilter build-time configuration.
65  */
66 const char *avfilter_configuration(void);
67 
68 /**
69  * Return the libavfilter license.
70  */
71 const char *avfilter_license(void);
72 
73 typedef struct AVFilterContext AVFilterContext;
74 typedef struct AVFilterLink AVFilterLink;
75 typedef struct AVFilterPad AVFilterPad;
76 typedef struct AVFilterFormats AVFilterFormats;
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  * Lists of formats / etc. supported by an end of a link.
103  *
104  * This structure is directly part of AVFilterLink, in two copies:
105  * one for the source filter, one for the destination filter.
106 
107  * These lists are used for negotiating the format to actually be used,
108  * which will be loaded into the format and channel_layout members of
109  * AVFilterLink, when chosen.
110  */
111 typedef struct AVFilterFormatsConfig {
112 
113  /**
114  * List of supported formats (pixel or sample).
115  */
117 
118  /**
119  * Lists of supported sample rates, only for audio.
120  */
122 
123  /**
124  * Lists of supported channel layouts, only for audio.
125  */
127 
128  /**
129  * Lists of supported YUV color metadata, only for YUV video.
130  */
131  AVFilterFormats *color_spaces; ///< AVColorSpace
132  AVFilterFormats *color_ranges; ///< AVColorRange
133 
135 
136 /**
137  * The number of the filter inputs is not determined just by AVFilter.inputs.
138  * The filter might add additional inputs during initialization depending on the
139  * options supplied to it.
140  */
141 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
142 /**
143  * The number of the filter outputs is not determined just by AVFilter.outputs.
144  * The filter might add additional outputs during initialization depending on
145  * the options supplied to it.
146  */
147 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
148 /**
149  * The filter supports multithreading by splitting frames into multiple parts
150  * and processing them concurrently.
151  */
152 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
153 /**
154  * The filter is a "metadata" filter - it does not modify the frame data in any
155  * way. It may only affect the metadata (i.e. those fields copied by
156  * av_frame_copy_props()).
157  *
158  * More precisely, this means:
159  * - video: the data of any frame output by the filter must be exactly equal to
160  * some frame that is received on one of its inputs. Furthermore, all frames
161  * produced on a given output must correspond to frames received on the same
162  * input and their order must be unchanged. Note that the filter may still
163  * drop or duplicate the frames.
164  * - audio: the data produced by the filter on any of its outputs (viewed e.g.
165  * as an array of interleaved samples) must be exactly equal to the data
166  * received by the filter on one of its inputs.
167  */
168 #define AVFILTER_FLAG_METADATA_ONLY (1 << 3)
169 
170 /**
171  * The filter can create hardware frames using AVFilterContext.hw_device_ctx.
172  */
173 #define AVFILTER_FLAG_HWDEVICE (1 << 4)
174 /**
175  * Some filters support a generic "enable" expression option that can be used
176  * to enable or disable a filter in the timeline. Filters supporting this
177  * option have this flag set. When the enable expression is false, the default
178  * no-op filter_frame() function is called in place of the filter_frame()
179  * callback defined on each input pad, thus the frame is passed unchanged to
180  * the next filters.
181  */
182 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
183 /**
184  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
185  * have its filter_frame() callback(s) called as usual even when the enable
186  * expression is false. The filter will disable filtering within the
187  * filter_frame() callback(s) itself, for example executing code depending on
188  * the AVFilterContext->is_disabled value.
189  */
190 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
191 /**
192  * Handy mask to test whether the filter supports or no the timeline feature
193  * (internally or generically).
194  */
195 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
196 
197 /**
198  * Filter definition. This defines the pads a filter contains, and all the
199  * callback functions used to interact with the filter.
200  */
201 typedef struct AVFilter {
202  /**
203  * Filter name. Must be non-NULL and unique among filters.
204  */
205  const char *name;
206 
207  /**
208  * A description of the filter. May be NULL.
209  *
210  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
211  */
212  const char *description;
213 
214  /**
215  * List of static inputs.
216  *
217  * NULL if there are no (static) inputs. Instances of filters with
218  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
219  * this list.
220  */
222 
223  /**
224  * List of static outputs.
225  *
226  * NULL if there are no (static) outputs. Instances of filters with
227  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
228  * this list.
229  */
231 
232  /**
233  * A class for the private data, used to declare filter private AVOptions.
234  * This field is NULL for filters that do not declare any options.
235  *
236  * If this field is non-NULL, the first member of the filter private data
237  * must be a pointer to AVClass, which will be set by libavfilter generic
238  * code to this class.
239  */
241 
242  /**
243  * A combination of AVFILTER_FLAG_*
244  */
245  int flags;
246 
247  /*****************************************************************
248  * All fields below this line are not part of the public API. They
249  * may not be used outside of libavfilter and can be changed and
250  * removed at will.
251  * New public fields should be added right above.
252  *****************************************************************
253  */
254 
255  /**
256  * The number of entries in the list of inputs.
257  */
258  uint8_t nb_inputs;
259 
260  /**
261  * The number of entries in the list of outputs.
262  */
263  uint8_t nb_outputs;
264 
265  /**
266  * This field determines the state of the formats union.
267  * It is an enum FilterFormatsState value.
268  */
269  uint8_t formats_state;
270 
271  /**
272  * Filter pre-initialization function
273  *
274  * This callback will be called immediately after the filter context is
275  * allocated, to allow allocating and initing sub-objects.
276  *
277  * If this callback is not NULL, the uninit callback will be called on
278  * allocation failure.
279  *
280  * @return 0 on success,
281  * AVERROR code on failure (but the code will be
282  * dropped and treated as ENOMEM by the calling code)
283  */
285 
286  /**
287  * Filter initialization function.
288  *
289  * This callback will be called only once during the filter lifetime, after
290  * all the options have been set, but before links between filters are
291  * established and format negotiation is done.
292  *
293  * Basic filter initialization should be done here. Filters with dynamic
294  * inputs and/or outputs should create those inputs/outputs here based on
295  * provided options. No more changes to this filter's inputs/outputs can be
296  * done after this callback.
297  *
298  * This callback must not assume that the filter links exist or frame
299  * parameters are known.
300  *
301  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
302  * initialization fails, so this callback does not have to clean up on
303  * failure.
304  *
305  * @return 0 on success, a negative AVERROR on failure
306  */
308 
309  /**
310  * Filter uninitialization function.
311  *
312  * Called only once right before the filter is freed. Should deallocate any
313  * memory held by the filter, release any buffer references, etc. It does
314  * not need to deallocate the AVFilterContext.priv memory itself.
315  *
316  * This callback may be called even if @ref AVFilter.init "init" was not
317  * called or failed, so it must be prepared to handle such a situation.
318  */
320 
321  /**
322  * The state of the following union is determined by formats_state.
323  * See the documentation of enum FilterFormatsState in internal.h.
324  */
325  union {
326  /**
327  * Query formats supported by the filter on its inputs and outputs.
328  *
329  * This callback is called after the filter is initialized (so the inputs
330  * and outputs are fixed), shortly before the format negotiation. This
331  * callback may be called more than once.
332  *
333  * This callback must set ::AVFilterLink's
334  * @ref AVFilterFormatsConfig.formats "outcfg.formats"
335  * on every input link and
336  * @ref AVFilterFormatsConfig.formats "incfg.formats"
337  * on every output link to a list of pixel/sample formats that the filter
338  * supports on that link.
339  * For video links, this filter may also set
340  * @ref AVFilterFormatsConfig.color_spaces "incfg.color_spaces"
341  * /
342  * @ref AVFilterFormatsConfig.color_spaces "outcfg.color_spaces"
343  * and @ref AVFilterFormatsConfig.color_ranges "incfg.color_ranges"
344  * /
345  * @ref AVFilterFormatsConfig.color_ranges "outcfg.color_ranges"
346  * analogously.
347  * For audio links, this filter must also set
348  * @ref AVFilterFormatsConfig.samplerates "incfg.samplerates"
349  * /
350  * @ref AVFilterFormatsConfig.samplerates "outcfg.samplerates"
351  * and @ref AVFilterFormatsConfig.channel_layouts "incfg.channel_layouts"
352  * /
353  * @ref AVFilterFormatsConfig.channel_layouts "outcfg.channel_layouts"
354  * analogously.
355  *
356  * This callback must never be NULL if the union is in this state.
357  *
358  * @return zero on success, a negative value corresponding to an
359  * AVERROR code otherwise
360  */
362 
363  /**
364  * Same as query_func(), except this function writes the results into
365  * provided arrays.
366  *
367  * @param cfg_in array of input format configurations with as many
368  * members as the filters has inputs (NULL when there are
369  * no inputs);
370  * @param cfg_out array of output format configurations with as many
371  * members as the filters has outputs (NULL when there
372  * are no outputs);
373  */
374  int (*query_func2)(const AVFilterContext *,
375  struct AVFilterFormatsConfig **cfg_in,
376  struct AVFilterFormatsConfig **cfg_out);
377  /**
378  * A pointer to an array of admissible pixel formats delimited
379  * by AV_PIX_FMT_NONE. The generic code will use this list
380  * to indicate that this filter supports each of these pixel formats,
381  * provided that all inputs and outputs use the same pixel format.
382  *
383  * In addition to that the generic code will mark all inputs
384  * and all outputs as supporting all color spaces and ranges, as
385  * long as all inputs and outputs use the same color space/range.
386  *
387  * This list must never be NULL if the union is in this state.
388  * The type of all inputs and outputs of filters using this must
389  * be AVMEDIA_TYPE_VIDEO.
390  */
392  /**
393  * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
394  * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
395  * inputs and outputs.
396  *
397  * In addition to that the generic code will mark all inputs
398  * and all outputs as supporting all sample rates and every
399  * channel count and channel layout, as long as all inputs
400  * and outputs use the same sample rate and channel count/layout.
401  */
403  /**
404  * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
405  */
407  /**
408  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
409  */
411  } formats;
412 
413  int priv_size; ///< size of private data to allocate for the filter
414 
415  int flags_internal; ///< Additional flags for avfilter internal use only.
416 
417  /**
418  * Make the filter instance process a command.
419  *
420  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
421  * @param arg the argument for the command
422  * @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.
423  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
424  * time consuming then a filter should treat it like an unsupported command
425  *
426  * @returns >=0 on success otherwise an error code.
427  * AVERROR(ENOSYS) on unsupported commands
428  */
429  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
430 
431  /**
432  * Filter activation function.
433  *
434  * Called when any processing is needed from the filter, instead of any
435  * filter_frame and request_frame on pads.
436  *
437  * The function must examine inlinks and outlinks and perform a single
438  * step of processing. If there is nothing to do, the function must do
439  * nothing and not return an error. If more steps are or may be
440  * possible, it must use ff_filter_set_ready() to schedule another
441  * activation.
442  */
444 } AVFilter;
445 
446 /**
447  * Get the number of elements in an AVFilter's inputs or outputs array.
448  */
449 unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
450 
451 /**
452  * Process multiple parts of the frame concurrently.
453  */
454 #define AVFILTER_THREAD_SLICE (1 << 0)
455 
456 /** An instance of a filter */
458  const AVClass *av_class; ///< needed for av_log() and filters common options
459 
460  const AVFilter *filter; ///< the AVFilter of which this is an instance
461 
462  char *name; ///< name of this filter instance
463 
464  AVFilterPad *input_pads; ///< array of input pads
465  AVFilterLink **inputs; ///< array of pointers to input links
466  unsigned nb_inputs; ///< number of input pads
467 
468  AVFilterPad *output_pads; ///< array of output pads
469  AVFilterLink **outputs; ///< array of pointers to output links
470  unsigned nb_outputs; ///< number of output pads
471 
472  void *priv; ///< private data for use by the filter
473 
474  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
475 
476  /**
477  * Type of multithreading being allowed/used. A combination of
478  * AVFILTER_THREAD_* flags.
479  *
480  * May be set by the caller before initializing the filter to forbid some
481  * or all kinds of multithreading for this filter. The default is allowing
482  * everything.
483  *
484  * When the filter is initialized, this field is combined using bit AND with
485  * AVFilterGraph.thread_type to get the final mask used for determining
486  * allowed threading types. I.e. a threading type needs to be set in both
487  * to be allowed.
488  *
489  * After the filter is initialized, libavfilter sets this field to the
490  * threading type that is actually used (0 for no multithreading).
491  */
493 
494  /**
495  * Max number of threads allowed in this filter instance.
496  * If <= 0, its value is ignored.
497  * Overrides global number of threads set per filter graph.
498  */
500 
501 #if FF_API_CONTEXT_PUBLIC
502  /**
503  * @deprecated unused
504  */
506  struct AVFilterCommand *command_queue;
507 #endif
508 
509  char *enable_str; ///< enable expression string
510 #if FF_API_CONTEXT_PUBLIC
511  /**
512  * @deprecated unused
513  */
515  void *enable;
516  /**
517  * @deprecated unused
518  */
519  double *var_values;
520 #endif
521  /**
522  * MUST NOT be accessed from outside avfilter.
523  *
524  * the enabled state from the last expression evaluation
525  */
527 
528  /**
529  * For filters which will create hardware frames, sets the device the
530  * filter should create them in. All other filters will ignore this field:
531  * in particular, a filter which consumes or processes hardware frames will
532  * instead use the hw_frames_ctx field in AVFilterLink to carry the
533  * hardware context information.
534  *
535  * May be set by the caller on filters flagged with AVFILTER_FLAG_HWDEVICE
536  * before initializing the filter with avfilter_init_str() or
537  * avfilter_init_dict().
538  */
540 
541 #if FF_API_CONTEXT_PUBLIC
542  /**
543  * @deprecated this field should never have been accessed by callers
544  */
546  unsigned ready;
547 #endif
548 
549  /**
550  * Sets the number of extra hardware frames which the filter will
551  * allocate on its output links for use in following filters or by
552  * the caller.
553  *
554  * Some hardware filters require all frames that they will use for
555  * output to be defined in advance before filtering starts. For such
556  * filters, any hardware frame pools used for output must therefore be
557  * of fixed size. The extra frames set here are on top of any number
558  * that the filter needs internally in order to operate normally.
559  *
560  * This field must be set before the graph containing this filter is
561  * configured.
562  */
564 };
565 
566 /**
567  * A link between two filters. This contains pointers to the source and
568  * destination filters between which this link exists, and the indexes of
569  * the pads involved. In addition, this link also contains the parameters
570  * which have been negotiated and agreed upon between the filter, such as
571  * image dimensions, format, etc.
572  *
573  * Applications must not normally access the link structure directly.
574  * Use the buffersrc and buffersink API instead.
575  * In the future, access to the header may be reserved for filters
576  * implementation.
577  */
578 struct AVFilterLink {
579  AVFilterContext *src; ///< source filter
580  AVFilterPad *srcpad; ///< output pad on the source filter
581 
582  AVFilterContext *dst; ///< dest filter
583  AVFilterPad *dstpad; ///< input pad on the dest filter
584 
585  enum AVMediaType type; ///< filter media type
586 
587  int format; ///< agreed upon media format
588 
589  /* These parameters apply only to video */
590  int w; ///< agreed upon image width
591  int h; ///< agreed upon image height
592  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
593  /**
594  * For non-YUV links, these are respectively set to fallback values (as
595  * appropriate for that colorspace).
596  *
597  * Note: This includes grayscale formats, as these are currently treated
598  * as forced full range always.
599  */
600  enum AVColorSpace colorspace; ///< agreed upon YUV color space
601  enum AVColorRange color_range; ///< agreed upon YUV color range
602 
603  /* These parameters apply only to audio */
604  int sample_rate; ///< samples per second
605  AVChannelLayout ch_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
606 
607  /**
608  * Define the time base used by the PTS of the frames/samples
609  * which will pass through this link.
610  * During the configuration stage, each filter is supposed to
611  * change only the output timebase, while the timebase of the
612  * input link is assumed to be an unchangeable property.
613  */
615 
616  /*****************************************************************
617  * All fields below this line are not part of the public API. They
618  * may not be used outside of libavfilter and can be changed and
619  * removed at will.
620  * New public fields should be added right above.
621  *****************************************************************
622  */
623 
624  /**
625  * Lists of supported formats / etc. supported by the input filter.
626  */
628 
629  /**
630  * Lists of supported formats / etc. supported by the output filter.
631  */
633 };
634 
635 /**
636  * Link two filters together.
637  *
638  * @param src the source filter
639  * @param srcpad index of the output pad on the source filter
640  * @param dst the destination filter
641  * @param dstpad index of the input pad on the destination filter
642  * @return zero on success
643  */
644 int avfilter_link(AVFilterContext *src, unsigned srcpad,
645  AVFilterContext *dst, unsigned dstpad);
646 
647 #if FF_API_LINK_PUBLIC
648 /**
649  * @deprecated this function should never be called by users
650  */
652 void avfilter_link_free(AVFilterLink **link);
653 
654 /**
655  * @deprecated this function should never be called by users
656  */
658 int avfilter_config_links(AVFilterContext *filter);
659 #endif
660 
661 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
662 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
663 
664 /**
665  * Make the filter instance process a command.
666  * It is recommended to use avfilter_graph_send_command().
667  */
668 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
669 
670 /**
671  * Iterate over all registered filters.
672  *
673  * @param opaque a pointer where libavfilter will store the iteration state. Must
674  * point to NULL to start the iteration.
675  *
676  * @return the next registered filter or NULL when the iteration is
677  * finished
678  */
679 const AVFilter *av_filter_iterate(void **opaque);
680 
681 /**
682  * Get a filter definition matching the given name.
683  *
684  * @param name the filter name to find
685  * @return the filter definition, if any matching one is registered.
686  * NULL if none found.
687  */
688 const AVFilter *avfilter_get_by_name(const char *name);
689 
690 
691 /**
692  * Initialize a filter with the supplied parameters.
693  *
694  * @param ctx uninitialized filter context to initialize
695  * @param args Options to initialize the filter with. This must be a
696  * ':'-separated list of options in the 'key=value' form.
697  * May be NULL if the options have been set directly using the
698  * AVOptions API or there are no options that need to be set.
699  * @return 0 on success, a negative AVERROR on failure
700  */
701 int avfilter_init_str(AVFilterContext *ctx, const char *args);
702 
703 /**
704  * Initialize a filter with the supplied dictionary of options.
705  *
706  * @param ctx uninitialized filter context to initialize
707  * @param options An AVDictionary filled with options for this filter. On
708  * return this parameter will be destroyed and replaced with
709  * a dict containing options that were not found. This dictionary
710  * must be freed by the caller.
711  * May be NULL, then this function is equivalent to
712  * avfilter_init_str() with the second parameter set to NULL.
713  * @return 0 on success, a negative AVERROR on failure
714  *
715  * @note This function and avfilter_init_str() do essentially the same thing,
716  * the difference is in manner in which the options are passed. It is up to the
717  * calling code to choose whichever is more preferable. The two functions also
718  * behave differently when some of the provided options are not declared as
719  * supported by the filter. In such a case, avfilter_init_str() will fail, but
720  * this function will leave those extra options in the options AVDictionary and
721  * continue as usual.
722  */
724 
725 /**
726  * Free a filter context. This will also remove the filter from its
727  * filtergraph's list of filters.
728  *
729  * @param filter the filter to free
730  */
732 
733 /**
734  * Insert a filter in the middle of an existing link.
735  *
736  * @param link the link into which the filter should be inserted
737  * @param filt the filter to be inserted
738  * @param filt_srcpad_idx the input pad on the filter to connect
739  * @param filt_dstpad_idx the output pad on the filter to connect
740  * @return zero on success
741  */
743  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
744 
745 /**
746  * @return AVClass for AVFilterContext.
747  *
748  * @see av_opt_find().
749  */
750 const AVClass *avfilter_get_class(void);
751 
752 /**
753  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
754  * executed multiple times, possibly in parallel.
755  *
756  * @param ctx the filter context the job belongs to
757  * @param arg an opaque parameter passed through from @ref
758  * AVFilterGraph.execute
759  * @param jobnr the index of the job being executed
760  * @param nb_jobs the total number of jobs
761  *
762  * @return 0 on success, a negative AVERROR on error
763  */
764 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
765 
766 /**
767  * A function executing multiple jobs, possibly in parallel.
768  *
769  * @param ctx the filter context to which the jobs belong
770  * @param func the function to be called multiple times
771  * @param arg the argument to be passed to func
772  * @param ret a nb_jobs-sized array to be filled with return values from each
773  * invocation of func
774  * @param nb_jobs the number of jobs to execute
775  *
776  * @return 0 on success, a negative AVERROR on error
777  */
779  void *arg, int *ret, int nb_jobs);
780 
781 typedef struct AVFilterGraph {
784  unsigned nb_filters;
785 
786  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
787 
788  /**
789  * Type of multithreading allowed for filters in this graph. A combination
790  * of AVFILTER_THREAD_* flags.
791  *
792  * May be set by the caller at any point, the setting will apply to all
793  * filters initialized after that. The default is allowing everything.
794  *
795  * When a filter in this graph is initialized, this field is combined using
796  * bit AND with AVFilterContext.thread_type to get the final mask used for
797  * determining allowed threading types. I.e. a threading type needs to be
798  * set in both to be allowed.
799  */
801 
802  /**
803  * Maximum number of threads used by filters in this graph. May be set by
804  * the caller before adding any filters to the filtergraph. Zero (the
805  * default) means that the number of threads is determined automatically.
806  */
808 
809  /**
810  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
811  * be used from callbacks like @ref AVFilterGraph.execute.
812  * Libavfilter will not touch this field in any way.
813  */
814  void *opaque;
815 
816  /**
817  * This callback may be set by the caller immediately after allocating the
818  * graph and before adding any filters to it, to provide a custom
819  * multithreading implementation.
820  *
821  * If set, filters with slice threading capability will call this callback
822  * to execute multiple jobs in parallel.
823  *
824  * If this field is left unset, libavfilter will use its internal
825  * implementation, which may or may not be multithreaded depending on the
826  * platform and build options.
827  */
829 
830  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
831 } AVFilterGraph;
832 
833 /**
834  * Allocate a filter graph.
835  *
836  * @return the allocated filter graph on success or NULL.
837  */
839 
840 /**
841  * Create a new filter instance in a filter graph.
842  *
843  * @param graph graph in which the new filter will be used
844  * @param filter the filter to create an instance of
845  * @param name Name to give to the new instance (will be copied to
846  * AVFilterContext.name). This may be used by the caller to identify
847  * different filters, libavfilter itself assigns no semantics to
848  * this parameter. May be NULL.
849  *
850  * @return the context of the newly created filter instance (note that it is
851  * also retrievable directly through AVFilterGraph.filters or with
852  * avfilter_graph_get_filter()) on success or NULL on failure.
853  */
855  const AVFilter *filter,
856  const char *name);
857 
858 /**
859  * Get a filter instance identified by instance name from graph.
860  *
861  * @param graph filter graph to search through.
862  * @param name filter instance name (should be unique in the graph).
863  * @return the pointer to the found filter instance or NULL if it
864  * cannot be found.
865  */
867 
868 /**
869  * A convenience wrapper that allocates and initializes a filter in a single
870  * step. The filter instance is created from the filter filt and inited with the
871  * parameter args. opaque is currently ignored.
872  *
873  * In case of success put in *filt_ctx the pointer to the created
874  * filter instance, otherwise set *filt_ctx to NULL.
875  *
876  * @param name the instance name to give to the created filter instance
877  * @param graph_ctx the filter graph
878  * @return a negative AVERROR error code in case of failure, a non
879  * negative value otherwise
880  *
881  * @warning Since the filter is initialized after this function successfully
882  * returns, you MUST NOT set any further options on it. If you need to
883  * do that, call ::avfilter_graph_alloc_filter(), followed by setting
884  * the options, followed by ::avfilter_init_dict() instead of this
885  * function.
886  */
888  const char *name, const char *args, void *opaque,
889  AVFilterGraph *graph_ctx);
890 
891 /**
892  * Enable or disable automatic format conversion inside the graph.
893  *
894  * Note that format conversion can still happen inside explicitly inserted
895  * scale and aresample filters.
896  *
897  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
898  */
900 
901 enum {
902  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
903  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
904 };
905 
906 /**
907  * Check validity and configure all the links and formats in the graph.
908  *
909  * @param graphctx the filter graph
910  * @param log_ctx context used for logging
911  * @return >= 0 in case of success, a negative AVERROR code otherwise
912  */
913 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
914 
915 /**
916  * Free a graph, destroy its links, and set *graph to NULL.
917  * If *graph is NULL, do nothing.
918  */
919 void avfilter_graph_free(AVFilterGraph **graph);
920 
921 /**
922  * A linked-list of the inputs/outputs of the filter chain.
923  *
924  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
925  * where it is used to communicate open (unlinked) inputs and outputs from and
926  * to the caller.
927  * This struct specifies, per each not connected pad contained in the graph, the
928  * filter context and the pad index required for establishing a link.
929  */
930 typedef struct AVFilterInOut {
931  /** unique name for this input/output in the list */
932  char *name;
933 
934  /** filter context associated to this input/output */
936 
937  /** index of the filt_ctx pad to use for linking */
938  int pad_idx;
939 
940  /** next input/input in the list, NULL if this is the last */
942 } AVFilterInOut;
943 
944 /**
945  * Allocate a single AVFilterInOut entry.
946  * Must be freed with avfilter_inout_free().
947  * @return allocated AVFilterInOut on success, NULL on failure.
948  */
950 
951 /**
952  * Free the supplied list of AVFilterInOut and set *inout to NULL.
953  * If *inout is NULL, do nothing.
954  */
955 void avfilter_inout_free(AVFilterInOut **inout);
956 
957 /**
958  * Add a graph described by a string to a graph.
959  *
960  * @note The caller must provide the lists of inputs and outputs,
961  * which therefore must be known before calling the function.
962  *
963  * @note The inputs parameter describes inputs of the already existing
964  * part of the graph; i.e. from the point of view of the newly created
965  * part, they are outputs. Similarly the outputs parameter describes
966  * outputs of the already existing filters, which are provided as
967  * inputs to the parsed filters.
968  *
969  * @param graph the filter graph where to link the parsed graph context
970  * @param filters string to be parsed
971  * @param inputs linked list to the inputs of the graph
972  * @param outputs linked list to the outputs of the graph
973  * @return zero on success, a negative AVERROR code on error
974  */
975 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
977  void *log_ctx);
978 
979 /**
980  * Add a graph described by a string to a graph.
981  *
982  * In the graph filters description, if the input label of the first
983  * filter is not specified, "in" is assumed; if the output label of
984  * the last filter is not specified, "out" is assumed.
985  *
986  * @param graph the filter graph where to link the parsed graph context
987  * @param filters string to be parsed
988  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
989  * If non-NULL, *inputs is updated to contain the list of open inputs
990  * after the parsing, should be freed with avfilter_inout_free().
991  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
992  * If non-NULL, *outputs is updated to contain the list of open outputs
993  * after the parsing, should be freed with avfilter_inout_free().
994  * @return non negative on success, a negative AVERROR code on error
995  */
996 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
998  void *log_ctx);
999 
1000 /**
1001  * Add a graph described by a string to a graph.
1002  *
1003  * @param[in] graph the filter graph where to link the parsed graph context
1004  * @param[in] filters string to be parsed
1005  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1006  * parsed graph will be returned here. It is to be freed
1007  * by the caller using avfilter_inout_free().
1008  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1009  * parsed graph will be returned here. It is to be freed by the
1010  * caller using avfilter_inout_free().
1011  * @return zero on success, a negative AVERROR code on error
1012  *
1013  * @note This function returns the inputs and outputs that are left
1014  * unlinked after parsing the graph and the caller then deals with
1015  * them.
1016  * @note This function makes no reference whatsoever to already
1017  * existing parts of the graph and the inputs parameter will on return
1018  * contain inputs of the newly parsed part of the graph. Analogously
1019  * the outputs parameter will contain outputs of the newly created
1020  * filters.
1021  */
1022 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1025 
1026 /**
1027  * Parameters of a filter's input or output pad.
1028  *
1029  * Created as a child of AVFilterParams by avfilter_graph_segment_parse().
1030  * Freed in avfilter_graph_segment_free().
1031  */
1032 typedef struct AVFilterPadParams {
1033  /**
1034  * An av_malloc()'ed string containing the pad label.
1035  *
1036  * May be av_free()'d and set to NULL by the caller, in which case this pad
1037  * will be treated as unlabeled for linking.
1038  * May also be replaced by another av_malloc()'ed string.
1039  */
1040  char *label;
1042 
1043 /**
1044  * Parameters describing a filter to be created in a filtergraph.
1045  *
1046  * Created as a child of AVFilterGraphSegment by avfilter_graph_segment_parse().
1047  * Freed in avfilter_graph_segment_free().
1048  */
1049 typedef struct AVFilterParams {
1050  /**
1051  * The filter context.
1052  *
1053  * Created by avfilter_graph_segment_create_filters() based on
1054  * AVFilterParams.filter_name and instance_name.
1055  *
1056  * Callers may also create the filter context manually, then they should
1057  * av_free() filter_name and set it to NULL. Such AVFilterParams instances
1058  * are then skipped by avfilter_graph_segment_create_filters().
1059  */
1061 
1062  /**
1063  * Name of the AVFilter to be used.
1064  *
1065  * An av_malloc()'ed string, set by avfilter_graph_segment_parse(). Will be
1066  * passed to avfilter_get_by_name() by
1067  * avfilter_graph_segment_create_filters().
1068  *
1069  * Callers may av_free() this string and replace it with another one or
1070  * NULL. If the caller creates the filter instance manually, this string
1071  * MUST be set to NULL.
1072  *
1073  * When both AVFilterParams.filter an AVFilterParams.filter_name are NULL,
1074  * this AVFilterParams instance is skipped by avfilter_graph_segment_*()
1075  * functions.
1076  */
1078  /**
1079  * Name to be used for this filter instance.
1080  *
1081  * An av_malloc()'ed string, may be set by avfilter_graph_segment_parse() or
1082  * left NULL. The caller may av_free() this string and replace with another
1083  * one or NULL.
1084  *
1085  * Will be used by avfilter_graph_segment_create_filters() - passed as the
1086  * third argument to avfilter_graph_alloc_filter(), then freed and set to
1087  * NULL.
1088  */
1090 
1091  /**
1092  * Options to be apllied to the filter.
1093  *
1094  * Filled by avfilter_graph_segment_parse(). Afterwards may be freely
1095  * modified by the caller.
1096  *
1097  * Will be applied to the filter by avfilter_graph_segment_apply_opts()
1098  * with an equivalent of av_opt_set_dict2(filter, &opts, AV_OPT_SEARCH_CHILDREN),
1099  * i.e. any unapplied options will be left in this dictionary.
1100  */
1102 
1104  unsigned nb_inputs;
1105 
1107  unsigned nb_outputs;
1108 } AVFilterParams;
1109 
1110 /**
1111  * A filterchain is a list of filter specifications.
1112  *
1113  * Created as a child of AVFilterGraphSegment by avfilter_graph_segment_parse().
1114  * Freed in avfilter_graph_segment_free().
1115  */
1116 typedef struct AVFilterChain {
1118  size_t nb_filters;
1119 } AVFilterChain;
1120 
1121 /**
1122  * A parsed representation of a filtergraph segment.
1123  *
1124  * A filtergraph segment is conceptually a list of filterchains, with some
1125  * supplementary information (e.g. format conversion flags).
1126  *
1127  * Created by avfilter_graph_segment_parse(). Must be freed with
1128  * avfilter_graph_segment_free().
1129  */
1130 typedef struct AVFilterGraphSegment {
1131  /**
1132  * The filtergraph this segment is associated with.
1133  * Set by avfilter_graph_segment_parse().
1134  */
1136 
1137  /**
1138  * A list of filter chain contained in this segment.
1139  * Set in avfilter_graph_segment_parse().
1140  */
1142  size_t nb_chains;
1143 
1144  /**
1145  * A string containing a colon-separated list of key=value options applied
1146  * to all scale filters in this segment.
1147  *
1148  * May be set by avfilter_graph_segment_parse().
1149  * The caller may free this string with av_free() and replace it with a
1150  * different av_malloc()'ed string.
1151  */
1154 
1155 /**
1156  * Parse a textual filtergraph description into an intermediate form.
1157  *
1158  * This intermediate representation is intended to be modified by the caller as
1159  * described in the documentation of AVFilterGraphSegment and its children, and
1160  * then applied to the graph either manually or with other
1161  * avfilter_graph_segment_*() functions. See the documentation for
1162  * avfilter_graph_segment_apply() for the canonical way to apply
1163  * AVFilterGraphSegment.
1164  *
1165  * @param graph Filter graph the parsed segment is associated with. Will only be
1166  * used for logging and similar auxiliary purposes. The graph will
1167  * not be actually modified by this function - the parsing results
1168  * are instead stored in seg for further processing.
1169  * @param graph_str a string describing the filtergraph segment
1170  * @param flags reserved for future use, caller must set to 0 for now
1171  * @param seg A pointer to the newly-created AVFilterGraphSegment is written
1172  * here on success. The graph segment is owned by the caller and must
1173  * be freed with avfilter_graph_segment_free() before graph itself is
1174  * freed.
1175  *
1176  * @retval "non-negative number" success
1177  * @retval "negative error code" failure
1178  */
1179 int avfilter_graph_segment_parse(AVFilterGraph *graph, const char *graph_str,
1180  int flags, AVFilterGraphSegment **seg);
1181 
1182 /**
1183  * Create filters specified in a graph segment.
1184  *
1185  * Walk through the creation-pending AVFilterParams in the segment and create
1186  * new filter instances for them.
1187  * Creation-pending params are those where AVFilterParams.filter_name is
1188  * non-NULL (and hence AVFilterParams.filter is NULL). All other AVFilterParams
1189  * instances are ignored.
1190  *
1191  * For any filter created by this function, the corresponding
1192  * AVFilterParams.filter is set to the newly-created filter context,
1193  * AVFilterParams.filter_name and AVFilterParams.instance_name are freed and set
1194  * to NULL.
1195  *
1196  * @param seg the filtergraph segment to process
1197  * @param flags reserved for future use, caller must set to 0 for now
1198  *
1199  * @retval "non-negative number" Success, all creation-pending filters were
1200  * successfully created
1201  * @retval AVERROR_FILTER_NOT_FOUND some filter's name did not correspond to a
1202  * known filter
1203  * @retval "another negative error code" other failures
1204  *
1205  * @note Calling this function multiple times is safe, as it is idempotent.
1206  */
1208 
1209 /**
1210  * Apply parsed options to filter instances in a graph segment.
1211  *
1212  * Walk through all filter instances in the graph segment that have option
1213  * dictionaries associated with them and apply those options with
1214  * av_opt_set_dict2(..., AV_OPT_SEARCH_CHILDREN). AVFilterParams.opts is
1215  * replaced by the dictionary output by av_opt_set_dict2(), which should be
1216  * empty (NULL) if all options were successfully applied.
1217  *
1218  * If any options could not be found, this function will continue processing all
1219  * other filters and finally return AVERROR_OPTION_NOT_FOUND (unless another
1220  * error happens). The calling program may then deal with unapplied options as
1221  * it wishes.
1222  *
1223  * Any creation-pending filters (see avfilter_graph_segment_create_filters())
1224  * present in the segment will cause this function to fail. AVFilterParams with
1225  * no associated filter context are simply skipped.
1226  *
1227  * @param seg the filtergraph segment to process
1228  * @param flags reserved for future use, caller must set to 0 for now
1229  *
1230  * @retval "non-negative number" Success, all options were successfully applied.
1231  * @retval AVERROR_OPTION_NOT_FOUND some options were not found in a filter
1232  * @retval "another negative error code" other failures
1233  *
1234  * @note Calling this function multiple times is safe, as it is idempotent.
1235  */
1237 
1238 /**
1239  * Initialize all filter instances in a graph segment.
1240  *
1241  * Walk through all filter instances in the graph segment and call
1242  * avfilter_init_dict(..., NULL) on those that have not been initialized yet.
1243  *
1244  * Any creation-pending filters (see avfilter_graph_segment_create_filters())
1245  * present in the segment will cause this function to fail. AVFilterParams with
1246  * no associated filter context or whose filter context is already initialized,
1247  * are simply skipped.
1248  *
1249  * @param seg the filtergraph segment to process
1250  * @param flags reserved for future use, caller must set to 0 for now
1251  *
1252  * @retval "non-negative number" Success, all filter instances were successfully
1253  * initialized
1254  * @retval "negative error code" failure
1255  *
1256  * @note Calling this function multiple times is safe, as it is idempotent.
1257  */
1259 
1260 /**
1261  * Link filters in a graph segment.
1262  *
1263  * Walk through all filter instances in the graph segment and try to link all
1264  * unlinked input and output pads. Any creation-pending filters (see
1265  * avfilter_graph_segment_create_filters()) present in the segment will cause
1266  * this function to fail. Disabled filters and already linked pads are skipped.
1267  *
1268  * Every filter output pad that has a corresponding AVFilterPadParams with a
1269  * non-NULL label is
1270  * - linked to the input with the matching label, if one exists;
1271  * - exported in the outputs linked list otherwise, with the label preserved.
1272  * Unlabeled outputs are
1273  * - linked to the first unlinked unlabeled input in the next non-disabled
1274  * filter in the chain, if one exists
1275  * - exported in the ouputs linked list otherwise, with NULL label
1276  *
1277  * Similarly, unlinked input pads are exported in the inputs linked list.
1278  *
1279  * @param seg the filtergraph segment to process
1280  * @param flags reserved for future use, caller must set to 0 for now
1281  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1282  * filters in this graph segment will be returned here. It
1283  * is to be freed by the caller using avfilter_inout_free().
1284  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1285  * filters in this graph segment will be returned here. It
1286  * is to be freed by the caller using avfilter_inout_free().
1287  *
1288  * @retval "non-negative number" success
1289  * @retval "negative error code" failure
1290  *
1291  * @note Calling this function multiple times is safe, as it is idempotent.
1292  */
1296 
1297 /**
1298  * Apply all filter/link descriptions from a graph segment to the associated filtergraph.
1299  *
1300  * This functions is currently equivalent to calling the following in sequence:
1301  * - avfilter_graph_segment_create_filters();
1302  * - avfilter_graph_segment_apply_opts();
1303  * - avfilter_graph_segment_init();
1304  * - avfilter_graph_segment_link();
1305  * failing if any of them fails. This list may be extended in the future.
1306  *
1307  * Since the above functions are idempotent, the caller may call some of them
1308  * manually, then do some custom processing on the filtergraph, then call this
1309  * function to do the rest.
1310  *
1311  * @param seg the filtergraph segment to process
1312  * @param flags reserved for future use, caller must set to 0 for now
1313  * @param[out] inputs passed to avfilter_graph_segment_link()
1314  * @param[out] outputs passed to avfilter_graph_segment_link()
1315  *
1316  * @retval "non-negative number" success
1317  * @retval "negative error code" failure
1318  *
1319  * @note Calling this function multiple times is safe, as it is idempotent.
1320  */
1324 
1325 /**
1326  * Free the provided AVFilterGraphSegment and everything associated with it.
1327  *
1328  * @param seg double pointer to the AVFilterGraphSegment to be freed. NULL will
1329  * be written to this pointer on exit from this function.
1330  *
1331  * @note
1332  * The filter contexts (AVFilterParams.filter) are owned by AVFilterGraph rather
1333  * than AVFilterGraphSegment, so they are not freed.
1334  */
1336 
1337 /**
1338  * Send a command to one or more filter instances.
1339  *
1340  * @param graph the filter graph
1341  * @param target the filter(s) to which the command should be sent
1342  * "all" sends to all filters
1343  * otherwise it can be a filter or filter instance name
1344  * which will send the command to all matching filters.
1345  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1346  * @param arg the argument for the command
1347  * @param res a buffer with size res_size where the filter(s) can return a response.
1348  *
1349  * @returns >=0 on success otherwise an error code.
1350  * AVERROR(ENOSYS) on unsupported commands
1351  */
1352 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1353 
1354 /**
1355  * Queue a command for one or more filter instances.
1356  *
1357  * @param graph the filter graph
1358  * @param target the filter(s) to which the command should be sent
1359  * "all" sends to all filters
1360  * otherwise it can be a filter or filter instance name
1361  * which will send the command to all matching filters.
1362  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1363  * @param arg the argument for the command
1364  * @param ts time at which the command should be sent to the filter
1365  *
1366  * @note As this executes commands after this function returns, no return code
1367  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1368  */
1369 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1370 
1371 
1372 /**
1373  * Dump a graph into a human-readable string representation.
1374  *
1375  * @param graph the graph to dump
1376  * @param options formatting options; currently ignored
1377  * @return a string, or NULL in case of memory allocation failure;
1378  * the string must be freed using av_free
1379  */
1380 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1381 
1382 /**
1383  * Request a frame on the oldest sink link.
1384  *
1385  * If the request returns AVERROR_EOF, try the next.
1386  *
1387  * Note that this function is not meant to be the sole scheduling mechanism
1388  * of a filtergraph, only a convenience function to help drain a filtergraph
1389  * in a balanced way under normal circumstances.
1390  *
1391  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1392  * some of the sinks during the process.
1393  * When there are multiple sink links, in case the requested link
1394  * returns an EOF, this may cause a filter to flush pending frames
1395  * which are sent to another sink link, although unrequested.
1396  *
1397  * @return the return value of ff_request_frame(),
1398  * or AVERROR_EOF if all links returned AVERROR_EOF
1399  */
1401 
1402 /**
1403  * @}
1404  */
1405 
1406 #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:828
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:499
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:121
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:630
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:902
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:807
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:983
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:126
AVFilterParams::instance_name
char * instance_name
Name to be used for this filter instance.
Definition: avfilter.h:1089
avfilter_graph_segment_create_filters
int avfilter_graph_segment_create_filters(AVFilterGraphSegment *seg, int flags)
Create filters specified in a graph segment.
Definition: graphparser.c: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:391
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:240
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:764
AVFilter::pix_fmt
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:406
rational.h
AVFilterContext::is_disabled
int is_disabled
MUST NOT be accessed from outside avfilter.
Definition: avfilter.h:526
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:429
AVFilter::formats
union AVFilter::@307 formats
The state of the following union is determined by formats_state.
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:941
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:470
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:458
filter
void(* filter)(uint8_t *src, int stride, int qscale)
Definition: h263dsp.c:29
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:539
AVDictionary
Definition: dict.c:34
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:468
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:205
AVFilterParams::inputs
AVFilterPadParams ** inputs
Definition: avfilter.h:1103
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:117
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
AVFilterParams::outputs
AVFilterPadParams ** outputs
Definition: avfilter.h:1106
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)
A convenience wrapper that allocates and initializes a filter in a single step.
Definition: avfiltergraph.c:138
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:165
avfilter_graph_segment_link
int avfilter_graph_segment_link(AVFilterGraphSegment *seg, int flags, AVFilterInOut **inputs, AVFilterInOut **outputs)
Link filters in a graph segment.
Definition: graphparser.c:814
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:472
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:474
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:509
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:83
AVFilter::formats_state
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:269
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:292
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:623
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:563
avfilter_graph_segment_free
void avfilter_graph_segment_free(AVFilterGraphSegment **seg)
Free the provided AVFilterGraphSegment and everything associated with it.
Definition: graphparser.c:276
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:814
avfilter_graph_segment_parse
int avfilter_graph_segment_parse(AVFilterGraph *graph, const char *graph_str, int flags, AVFilterGraphSegment **seg)
Parse a textual filtergraph description into an intermediate form.
Definition: graphparser.c:460
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:415
AVFilterPad
A filter pad used for either input or output.
Definition: filters.h:38
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
Definition: version.c:41
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:464
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:76
AVFilterChain::filters
AVFilterParams ** filters
Definition: avfilter.h:1117
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:903
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:402
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:609
filters
#define filters(fmt, type, inverse, clp, inverset, clip, one, clip_fn, packed)
Definition: af_crystalizer.c:55
avfilter_graph_segment_init
int avfilter_graph_segment_init(AVFilterGraphSegment *seg, int flags)
Initialize all filter instances in a graph segment.
Definition: graphparser.c:616
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:245
ctx
AVFormatContext * ctx
Definition: movenc.c:49
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:830
AVFilterFormatsConfig::color_spaces
AVFilterFormats * color_spaces
Lists of supported YUV color metadata, only for YUV video.
Definition: avfilter.h:131
AVFilterPadParams::label
char * label
An av_malloc()'ed string containing the pad label.
Definition: avfilter.h:1040
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:443
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:634
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:75
AVFilterContext::thread_type
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:492
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:1294
avfilter_graph_segment_apply
int avfilter_graph_segment_apply(AVFilterGraphSegment *seg, int flags, AVFilterInOut **inputs, AVFilterInOut **outputs)
Apply all filter/link descriptions from a graph segment to the associated filtergraph.
Definition: graphparser.c:882
AVFilterParams
Parameters describing a filter to be created in a filtergraph.
Definition: avfilter.h:1049
AVFilter::outputs
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:230
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:160
AVFilterParams::filter
AVFilterContext * filter
The filter context.
Definition: avfilter.h:1060
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterChain::nb_filters
size_t nb_filters
Definition: avfilter.h:1118
AVFilterParams::filter_name
char * filter_name
Name of the AVFilter to be used.
Definition: avfilter.h:1077
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:783
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:465
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:462
avfilter_inout_alloc
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
Definition: graphparser.c:71
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:284
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1425
AVFilterGraphSegment::chains
AVFilterChain ** chains
A list of filter chain contained in this segment.
Definition: avfilter.h:1141
AVFilterGraph
Definition: avfilter.h:781
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:138
AVFilterParams::nb_outputs
unsigned nb_outputs
Definition: avfilter.h:1107
AVFilterFormatsConfig
Lists of formats / etc.
Definition: avfilter.h:111
AVFilterGraphSegment
A parsed representation of a filtergraph segment.
Definition: avfilter.h:1130
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:938
AVFilterGraph::scale_sws_opts
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:786
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:466
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:782
AVMediaType
AVMediaType
Definition: avutil.h:199
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:311
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:935
dst
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
Definition: dsp.h:83
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:778
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:284
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:149
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:1342
AVFilterGraphSegment::scale_sws_opts
char * scale_sws_opts
A string containing a colon-separated list of key=value options applied to all scale filters in this ...
Definition: avfilter.h:1152
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:212
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
attributes.h
AVFilterFormatsConfig::color_ranges
AVFilterFormats * color_ranges
AVColorRange.
Definition: avfilter.h:132
AVFilter::nb_inputs
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:258
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:307
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:955
AVFilterParams::nb_inputs
unsigned nb_inputs
Definition: avfilter.h:1104
AVFilter::query_func
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:361
log.h
AVFilterGraphSegment::graph
AVFilterGraph * graph
The filtergraph this segment is associated with.
Definition: avfilter.h:1135
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:920
AVFilterCommand
Definition: avfilter_internal.h:126
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:640
version_major.h
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
AVFilterGraph::thread_type
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:800
filt
static const int8_t filt[NUMTAPS *2]
Definition: af_earwax.c:40
outputs
static const AVFilterPad outputs[]
Definition: af_aap.c:310
AVFilter::priv_size
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:413
AVFilter
Filter definition.
Definition: avfilter.h:201
ret
ret
Definition: filter_design.txt:187
pixfmt.h
avfilter_configuration
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
Definition: version.c:36
AVFilterParams::opts
AVDictionary * opts
Options to be apllied to the filter.
Definition: avfilter.h:1101
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:156
dict.h
AVFilter::nb_outputs
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:263
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:988
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:914
AVFilterChain
A filterchain is a list of filter specifications.
Definition: avfilter.h:1116
version.h
AVFilterGraphSegment::nb_chains
size_t nb_chains
Definition: avfilter.h:1142
AVFilterContext
An instance of a filter.
Definition: avfilter.h:457
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:164
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:116
AVFilter::inputs
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:221
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:319
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:795
AVFilter::sample_fmt
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:410
ready
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 the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already ready
Definition: filter_design.txt:258
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:932
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:482
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:1312
avfilter_graph_segment_apply_opts
int avfilter_graph_segment_apply_opts(AVFilterGraphSegment *seg, int flags)
Apply parsed options to filter instances in a graph segment.
Definition: graphparser.c:586
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:784
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:460
AVFilter::query_func2
int(* query_func2)(const AVFilterContext *, struct AVFilterFormatsConfig **cfg_in, struct AVFilterFormatsConfig **cfg_out)
Same as query_func(), except this function writes the results into provided arrays.
Definition: avfilter.h:374
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:682
avfilter_version
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
Definition: version.c:30
avfilter_get_class
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1634
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:930
src
#define src
Definition: vp8dsp.c:248
AVFilterPadParams
Parameters of a filter's input or output pad.
Definition: avfilter.h:1032
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:469