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 #if FF_API_PAD_COUNT
80 /**
81  * Get the number of elements in an AVFilter's inputs or outputs array.
82  *
83  * @deprecated Use avfilter_filter_pad_count() instead.
84  */
86 int avfilter_pad_count(const AVFilterPad *pads);
87 #endif
88 
89 /**
90  * Get the name of an AVFilterPad.
91  *
92  * @param pads an array of AVFilterPads
93  * @param pad_idx index of the pad in the array; it is the caller's
94  * responsibility to ensure the index is valid
95  *
96  * @return name of the pad_idx'th pad in pads
97  */
98 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
99 
100 /**
101  * Get the type of an AVFilterPad.
102  *
103  * @param pads an array of AVFilterPads
104  * @param pad_idx index of the pad in the array; it is the caller's
105  * responsibility to ensure the index is valid
106  *
107  * @return type of the pad_idx'th pad in pads
108  */
109 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
110 
111 /**
112  * The number of the filter inputs is not determined just by AVFilter.inputs.
113  * The filter might add additional inputs during initialization depending on the
114  * options supplied to it.
115  */
116 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
117 /**
118  * The number of the filter outputs is not determined just by AVFilter.outputs.
119  * The filter might add additional outputs during initialization depending on
120  * the options supplied to it.
121  */
122 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
123 /**
124  * The filter supports multithreading by splitting frames into multiple parts
125  * and processing them concurrently.
126  */
127 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
128 /**
129  * The filter is a "metadata" filter - it does not modify the frame data in any
130  * way. It may only affect the metadata (i.e. those fields copied by
131  * av_frame_copy_props()).
132  *
133  * More precisely, this means:
134  * - video: the data of any frame output by the filter must be exactly equal to
135  * some frame that is received on one of its inputs. Furthermore, all frames
136  * produced on a given output must correspond to frames received on the same
137  * input and their order must be unchanged. Note that the filter may still
138  * drop or duplicate the frames.
139  * - audio: the data produced by the filter on any of its outputs (viewed e.g.
140  * as an array of interleaved samples) must be exactly equal to the data
141  * received by the filter on one of its inputs.
142  */
143 #define AVFILTER_FLAG_METADATA_ONLY (1 << 3)
144 /**
145  * Some filters support a generic "enable" expression option that can be used
146  * to enable or disable a filter in the timeline. Filters supporting this
147  * option have this flag set. When the enable expression is false, the default
148  * no-op filter_frame() function is called in place of the filter_frame()
149  * callback defined on each input pad, thus the frame is passed unchanged to
150  * the next filters.
151  */
152 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
153 /**
154  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
155  * have its filter_frame() callback(s) called as usual even when the enable
156  * expression is false. The filter will disable filtering within the
157  * filter_frame() callback(s) itself, for example executing code depending on
158  * the AVFilterContext->is_disabled value.
159  */
160 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
161 /**
162  * Handy mask to test whether the filter supports or no the timeline feature
163  * (internally or generically).
164  */
165 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
166 
167 /**
168  * Filter definition. This defines the pads a filter contains, and all the
169  * callback functions used to interact with the filter.
170  */
171 typedef struct AVFilter {
172  /**
173  * Filter name. Must be non-NULL and unique among filters.
174  */
175  const char *name;
176 
177  /**
178  * A description of the filter. May be NULL.
179  *
180  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
181  */
182  const char *description;
183 
184  /**
185  * List of static inputs.
186  *
187  * NULL if there are no (static) inputs. Instances of filters with
188  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
189  * this list.
190  */
192 
193  /**
194  * List of static outputs.
195  *
196  * NULL if there are no (static) outputs. Instances of filters with
197  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
198  * this list.
199  */
201 
202  /**
203  * A class for the private data, used to declare filter private AVOptions.
204  * This field is NULL for filters that do not declare any options.
205  *
206  * If this field is non-NULL, the first member of the filter private data
207  * must be a pointer to AVClass, which will be set by libavfilter generic
208  * code to this class.
209  */
211 
212  /**
213  * A combination of AVFILTER_FLAG_*
214  */
215  int flags;
216 
217  /*****************************************************************
218  * All fields below this line are not part of the public API. They
219  * may not be used outside of libavfilter and can be changed and
220  * removed at will.
221  * New public fields should be added right above.
222  *****************************************************************
223  */
224 
225  /**
226  * The number of entries in the list of inputs.
227  */
228  uint8_t nb_inputs;
229 
230  /**
231  * The number of entries in the list of outputs.
232  */
233  uint8_t nb_outputs;
234 
235  /**
236  * This field determines the state of the formats union.
237  * It is an enum FilterFormatsState value.
238  */
239  uint8_t formats_state;
240 
241  /**
242  * Filter pre-initialization function
243  *
244  * This callback will be called immediately after the filter context is
245  * allocated, to allow allocating and initing sub-objects.
246  *
247  * If this callback is not NULL, the uninit callback will be called on
248  * allocation failure.
249  *
250  * @return 0 on success,
251  * AVERROR code on failure (but the code will be
252  * dropped and treated as ENOMEM by the calling code)
253  */
255 
256  /**
257  * Filter initialization function.
258  *
259  * This callback will be called only once during the filter lifetime, after
260  * all the options have been set, but before links between filters are
261  * established and format negotiation is done.
262  *
263  * Basic filter initialization should be done here. Filters with dynamic
264  * inputs and/or outputs should create those inputs/outputs here based on
265  * provided options. No more changes to this filter's inputs/outputs can be
266  * done after this callback.
267  *
268  * This callback must not assume that the filter links exist or frame
269  * parameters are known.
270  *
271  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
272  * initialization fails, so this callback does not have to clean up on
273  * failure.
274  *
275  * @return 0 on success, a negative AVERROR on failure
276  */
278 
279  /**
280  * Should be set instead of @ref AVFilter.init "init" by the filters that
281  * want to pass a dictionary of AVOptions to nested contexts that are
282  * allocated during init.
283  *
284  * On return, the options dict should be freed and replaced with one that
285  * contains all the options which could not be processed by this filter (or
286  * with NULL if all the options were processed).
287  *
288  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
289  */
291 
292  /**
293  * Filter uninitialization function.
294  *
295  * Called only once right before the filter is freed. Should deallocate any
296  * memory held by the filter, release any buffer references, etc. It does
297  * not need to deallocate the AVFilterContext.priv memory itself.
298  *
299  * This callback may be called even if @ref AVFilter.init "init" was not
300  * called or failed, so it must be prepared to handle such a situation.
301  */
303 
304  /**
305  * The state of the following union is determined by formats_state.
306  * See the documentation of enum FilterFormatsState in internal.h.
307  */
308  union {
309  /**
310  * Query formats supported by the filter on its inputs and outputs.
311  *
312  * This callback is called after the filter is initialized (so the inputs
313  * and outputs are fixed), shortly before the format negotiation. This
314  * callback may be called more than once.
315  *
316  * This callback must set ::AVFilterLink's
317  * @ref AVFilterFormatsConfig.formats "outcfg.formats"
318  * on every input link and
319  * @ref AVFilterFormatsConfig.formats "incfg.formats"
320  * on every output link to a list of pixel/sample formats that the filter
321  * supports on that link.
322  * For audio links, this filter must also set
323  * @ref AVFilterFormatsConfig.samplerates "incfg.samplerates"
324  * /
325  * @ref AVFilterFormatsConfig.samplerates "outcfg.samplerates"
326  * and @ref AVFilterFormatsConfig.channel_layouts "incfg.channel_layouts"
327  * /
328  * @ref AVFilterFormatsConfig.channel_layouts "outcfg.channel_layouts"
329  * analogously.
330  *
331  * This callback must never be NULL if the union is in this state.
332  *
333  * @return zero on success, a negative value corresponding to an
334  * AVERROR code otherwise
335  */
337  /**
338  * A pointer to an array of admissible pixel formats delimited
339  * by AV_PIX_FMT_NONE. The generic code will use this list
340  * to indicate that this filter supports each of these pixel formats,
341  * provided that all inputs and outputs use the same pixel format.
342  *
343  * This list must never be NULL if the union is in this state.
344  * The type of all inputs and outputs of filters using this must
345  * be AVMEDIA_TYPE_VIDEO.
346  */
348  /**
349  * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
350  * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
351  * inputs and outputs.
352  *
353  * In addition to that the generic code will mark all inputs
354  * and all outputs as supporting all sample rates and every
355  * channel count and channel layout, as long as all inputs
356  * and outputs use the same sample rate and channel count/layout.
357  */
359  /**
360  * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
361  */
363  /**
364  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
365  */
367  } formats;
368 
369  int priv_size; ///< size of private data to allocate for the filter
370 
371  int flags_internal; ///< Additional flags for avfilter internal use only.
372 
373  /**
374  * Make the filter instance process a command.
375  *
376  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
377  * @param arg the argument for the command
378  * @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.
379  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
380  * time consuming then a filter should treat it like an unsupported command
381  *
382  * @returns >=0 on success otherwise an error code.
383  * AVERROR(ENOSYS) on unsupported commands
384  */
385  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
386 
387  /**
388  * Filter activation function.
389  *
390  * Called when any processing is needed from the filter, instead of any
391  * filter_frame and request_frame on pads.
392  *
393  * The function must examine inlinks and outlinks and perform a single
394  * step of processing. If there is nothing to do, the function must do
395  * nothing and not return an error. If more steps are or may be
396  * possible, it must use ff_filter_set_ready() to schedule another
397  * activation.
398  */
400 } AVFilter;
401 
402 /**
403  * Get the number of elements in an AVFilter's inputs or outputs array.
404  */
405 unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
406 
407 /**
408  * Process multiple parts of the frame concurrently.
409  */
410 #define AVFILTER_THREAD_SLICE (1 << 0)
411 
412 typedef struct AVFilterInternal AVFilterInternal;
413 
414 /** An instance of a filter */
416  const AVClass *av_class; ///< needed for av_log() and filters common options
417 
418  const AVFilter *filter; ///< the AVFilter of which this is an instance
419 
420  char *name; ///< name of this filter instance
421 
422  AVFilterPad *input_pads; ///< array of input pads
423  AVFilterLink **inputs; ///< array of pointers to input links
424  unsigned nb_inputs; ///< number of input pads
425 
426  AVFilterPad *output_pads; ///< array of output pads
427  AVFilterLink **outputs; ///< array of pointers to output links
428  unsigned nb_outputs; ///< number of output pads
429 
430  void *priv; ///< private data for use by the filter
431 
432  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
433 
434  /**
435  * Type of multithreading being allowed/used. A combination of
436  * AVFILTER_THREAD_* flags.
437  *
438  * May be set by the caller before initializing the filter to forbid some
439  * or all kinds of multithreading for this filter. The default is allowing
440  * everything.
441  *
442  * When the filter is initialized, this field is combined using bit AND with
443  * AVFilterGraph.thread_type to get the final mask used for determining
444  * allowed threading types. I.e. a threading type needs to be set in both
445  * to be allowed.
446  *
447  * After the filter is initialized, libavfilter sets this field to the
448  * threading type that is actually used (0 for no multithreading).
449  */
451 
452  /**
453  * An opaque struct for libavfilter internal use.
454  */
455  AVFilterInternal *internal;
456 
458 
459  char *enable_str; ///< enable expression string
460  void *enable; ///< parsed expression (AVExpr*)
461  double *var_values; ///< variable values for the enable expression
462  int is_disabled; ///< the enabled state from the last expression evaluation
463 
464  /**
465  * For filters which will create hardware frames, sets the device the
466  * filter should create them in. All other filters will ignore this field:
467  * in particular, a filter which consumes or processes hardware frames will
468  * instead use the hw_frames_ctx field in AVFilterLink to carry the
469  * hardware context information.
470  */
472 
473  /**
474  * Max number of threads allowed in this filter instance.
475  * If <= 0, its value is ignored.
476  * Overrides global number of threads set per filter graph.
477  */
479 
480  /**
481  * Ready status of the filter.
482  * A non-0 value means that the filter needs activating;
483  * a higher value suggests a more urgent activation.
484  */
485  unsigned ready;
486 
487  /**
488  * Sets the number of extra hardware frames which the filter will
489  * allocate on its output links for use in following filters or by
490  * the caller.
491  *
492  * Some hardware filters require all frames that they will use for
493  * output to be defined in advance before filtering starts. For such
494  * filters, any hardware frame pools used for output must therefore be
495  * of fixed size. The extra frames set here are on top of any number
496  * that the filter needs internally in order to operate normally.
497  *
498  * This field must be set before the graph containing this filter is
499  * configured.
500  */
502 };
503 
504 /**
505  * Lists of formats / etc. supported by an end of a link.
506  *
507  * This structure is directly part of AVFilterLink, in two copies:
508  * one for the source filter, one for the destination filter.
509 
510  * These lists are used for negotiating the format to actually be used,
511  * which will be loaded into the format and channel_layout members of
512  * AVFilterLink, when chosen.
513  */
514 typedef struct AVFilterFormatsConfig {
515 
516  /**
517  * List of supported formats (pixel or sample).
518  */
520 
521  /**
522  * Lists of supported sample rates, only for audio.
523  */
525 
526  /**
527  * Lists of supported channel layouts, only for audio.
528  */
530 
532 
533 /**
534  * A link between two filters. This contains pointers to the source and
535  * destination filters between which this link exists, and the indexes of
536  * the pads involved. In addition, this link also contains the parameters
537  * which have been negotiated and agreed upon between the filter, such as
538  * image dimensions, format, etc.
539  *
540  * Applications must not normally access the link structure directly.
541  * Use the buffersrc and buffersink API instead.
542  * In the future, access to the header may be reserved for filters
543  * implementation.
544  */
545 struct AVFilterLink {
546  AVFilterContext *src; ///< source filter
547  AVFilterPad *srcpad; ///< output pad on the source filter
548 
549  AVFilterContext *dst; ///< dest filter
550  AVFilterPad *dstpad; ///< input pad on the dest filter
551 
552  enum AVMediaType type; ///< filter media type
553 
554  /* These parameters apply only to video */
555  int w; ///< agreed upon image width
556  int h; ///< agreed upon image height
557  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
558  /* These parameters apply only to audio */
559 #if FF_API_OLD_CHANNEL_LAYOUT
560  /**
561  * channel layout of current buffer (see libavutil/channel_layout.h)
562  * @deprecated use ch_layout
563  */
565  uint64_t channel_layout;
566 #endif
567  int sample_rate; ///< samples per second
568 
569  int format; ///< agreed upon media format
570 
571  /**
572  * Define the time base used by the PTS of the frames/samples
573  * which will pass through this link.
574  * During the configuration stage, each filter is supposed to
575  * change only the output timebase, while the timebase of the
576  * input link is assumed to be an unchangeable property.
577  */
579 
580  AVChannelLayout ch_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
581 
582  /*****************************************************************
583  * All fields below this line are not part of the public API. They
584  * may not be used outside of libavfilter and can be changed and
585  * removed at will.
586  * New public fields should be added right above.
587  *****************************************************************
588  */
589 
590  /**
591  * Lists of supported formats / etc. supported by the input filter.
592  */
594 
595  /**
596  * Lists of supported formats / etc. supported by the output filter.
597  */
599 
600  /** stage of the initialization of the link properties (dimensions, etc) */
601  enum {
602  AVLINK_UNINIT = 0, ///< not started
603  AVLINK_STARTINIT, ///< started, but incomplete
604  AVLINK_INIT ///< complete
605  } init_state;
606 
607  /**
608  * Graph the filter belongs to.
609  */
611 
612  /**
613  * Current timestamp of the link, as defined by the most recent
614  * frame(s), in link time_base units.
615  */
616  int64_t current_pts;
617 
618  /**
619  * Current timestamp of the link, as defined by the most recent
620  * frame(s), in AV_TIME_BASE units.
621  */
622  int64_t current_pts_us;
623 
624  /**
625  * Index in the age array.
626  */
628 
629  /**
630  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
631  * if left to 0/0, will be automatically copied from the first input
632  * of the source filter if it exists.
633  *
634  * Sources should set it to the best estimation of the real frame rate.
635  * If the source frame rate is unknown or variable, set this to 1/0.
636  * Filters should update it if necessary depending on their function.
637  * Sinks can use it to set a default output frame rate.
638  * It is similar to the r_frame_rate field in AVStream.
639  */
641 
642  /**
643  * Minimum number of samples to filter at once. If filter_frame() is
644  * called with fewer samples, it will accumulate them in fifo.
645  * This field and the related ones must not be changed after filtering
646  * has started.
647  * If 0, all related fields are ignored.
648  */
650 
651  /**
652  * Maximum number of samples to filter at once. If filter_frame() is
653  * called with more samples, it will split them.
654  */
656 
657  /**
658  * Number of past frames sent through the link.
659  */
661 
662  /**
663  * Number of past samples sent through the link.
664  */
666 
667  /**
668  * A pointer to a FFFramePool struct.
669  */
670  void *frame_pool;
671 
672  /**
673  * True if a frame is currently wanted on the output of this filter.
674  * Set when ff_request_frame() is called by the output,
675  * cleared when a frame is filtered.
676  */
678 
679  /**
680  * For hwaccel pixel formats, this should be a reference to the
681  * AVHWFramesContext describing the frames.
682  */
684 
685 #ifndef FF_INTERNAL_FIELDS
686 
687  /**
688  * Internal structure members.
689  * The fields below this limit are internal for libavfilter's use
690  * and must in no way be accessed by applications.
691  */
692  char reserved[0xF000];
693 
694 #else /* FF_INTERNAL_FIELDS */
695 
696  /**
697  * Queue of frames waiting to be filtered.
698  */
699  FFFrameQueue fifo;
700 
701  /**
702  * If set, the source filter can not generate a frame as is.
703  * The goal is to avoid repeatedly calling the request_frame() method on
704  * the same link.
705  */
706  int frame_blocked_in;
707 
708  /**
709  * Link input status.
710  * If not zero, all attempts of filter_frame will fail with the
711  * corresponding code.
712  */
713  int status_in;
714 
715  /**
716  * Timestamp of the input status change.
717  */
718  int64_t status_in_pts;
719 
720  /**
721  * Link output status.
722  * If not zero, all attempts of request_frame will fail with the
723  * corresponding code.
724  */
725  int status_out;
726 
727 #endif /* FF_INTERNAL_FIELDS */
728 
729 };
730 
731 /**
732  * Link two filters together.
733  *
734  * @param src the source filter
735  * @param srcpad index of the output pad on the source filter
736  * @param dst the destination filter
737  * @param dstpad index of the input pad on the destination filter
738  * @return zero on success
739  */
740 int avfilter_link(AVFilterContext *src, unsigned srcpad,
741  AVFilterContext *dst, unsigned dstpad);
742 
743 /**
744  * Free the link in *link, and set its pointer to NULL.
745  */
747 
748 /**
749  * Negotiate the media format, dimensions, etc of all inputs to a filter.
750  *
751  * @param filter the filter to negotiate the properties for its inputs
752  * @return zero on successful negotiation
753  */
755 
756 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
757 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
758 
759 /**
760  * Make the filter instance process a command.
761  * It is recommended to use avfilter_graph_send_command().
762  */
763 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
764 
765 /**
766  * Iterate over all registered filters.
767  *
768  * @param opaque a pointer where libavfilter will store the iteration state. Must
769  * point to NULL to start the iteration.
770  *
771  * @return the next registered filter or NULL when the iteration is
772  * finished
773  */
774 const AVFilter *av_filter_iterate(void **opaque);
775 
776 /**
777  * Get a filter definition matching the given name.
778  *
779  * @param name the filter name to find
780  * @return the filter definition, if any matching one is registered.
781  * NULL if none found.
782  */
783 const AVFilter *avfilter_get_by_name(const char *name);
784 
785 
786 /**
787  * Initialize a filter with the supplied parameters.
788  *
789  * @param ctx uninitialized filter context to initialize
790  * @param args Options to initialize the filter with. This must be a
791  * ':'-separated list of options in the 'key=value' form.
792  * May be NULL if the options have been set directly using the
793  * AVOptions API or there are no options that need to be set.
794  * @return 0 on success, a negative AVERROR on failure
795  */
796 int avfilter_init_str(AVFilterContext *ctx, const char *args);
797 
798 /**
799  * Initialize a filter with the supplied dictionary of options.
800  *
801  * @param ctx uninitialized filter context to initialize
802  * @param options An AVDictionary filled with options for this filter. On
803  * return this parameter will be destroyed and replaced with
804  * a dict containing options that were not found. This dictionary
805  * must be freed by the caller.
806  * May be NULL, then this function is equivalent to
807  * avfilter_init_str() with the second parameter set to NULL.
808  * @return 0 on success, a negative AVERROR on failure
809  *
810  * @note This function and avfilter_init_str() do essentially the same thing,
811  * the difference is in manner in which the options are passed. It is up to the
812  * calling code to choose whichever is more preferable. The two functions also
813  * behave differently when some of the provided options are not declared as
814  * supported by the filter. In such a case, avfilter_init_str() will fail, but
815  * this function will leave those extra options in the options AVDictionary and
816  * continue as usual.
817  */
819 
820 /**
821  * Free a filter context. This will also remove the filter from its
822  * filtergraph's list of filters.
823  *
824  * @param filter the filter to free
825  */
827 
828 /**
829  * Insert a filter in the middle of an existing link.
830  *
831  * @param link the link into which the filter should be inserted
832  * @param filt the filter to be inserted
833  * @param filt_srcpad_idx the input pad on the filter to connect
834  * @param filt_dstpad_idx the output pad on the filter to connect
835  * @return zero on success
836  */
838  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
839 
840 /**
841  * @return AVClass for AVFilterContext.
842  *
843  * @see av_opt_find().
844  */
845 const AVClass *avfilter_get_class(void);
846 
848 
849 /**
850  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
851  * executed multiple times, possibly in parallel.
852  *
853  * @param ctx the filter context the job belongs to
854  * @param arg an opaque parameter passed through from @ref
855  * AVFilterGraph.execute
856  * @param jobnr the index of the job being executed
857  * @param nb_jobs the total number of jobs
858  *
859  * @return 0 on success, a negative AVERROR on error
860  */
861 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
862 
863 /**
864  * A function executing multiple jobs, possibly in parallel.
865  *
866  * @param ctx the filter context to which the jobs belong
867  * @param func the function to be called multiple times
868  * @param arg the argument to be passed to func
869  * @param ret a nb_jobs-sized array to be filled with return values from each
870  * invocation of func
871  * @param nb_jobs the number of jobs to execute
872  *
873  * @return 0 on success, a negative AVERROR on error
874  */
876  void *arg, int *ret, int nb_jobs);
877 
878 typedef struct AVFilterGraph {
881  unsigned nb_filters;
882 
883  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
884 
885  /**
886  * Type of multithreading allowed for filters in this graph. A combination
887  * of AVFILTER_THREAD_* flags.
888  *
889  * May be set by the caller at any point, the setting will apply to all
890  * filters initialized after that. The default is allowing everything.
891  *
892  * When a filter in this graph is initialized, this field is combined using
893  * bit AND with AVFilterContext.thread_type to get the final mask used for
894  * determining allowed threading types. I.e. a threading type needs to be
895  * set in both to be allowed.
896  */
898 
899  /**
900  * Maximum number of threads used by filters in this graph. May be set by
901  * the caller before adding any filters to the filtergraph. Zero (the
902  * default) means that the number of threads is determined automatically.
903  */
905 
906  /**
907  * Opaque object for libavfilter internal use.
908  */
910 
911  /**
912  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
913  * be used from callbacks like @ref AVFilterGraph.execute.
914  * Libavfilter will not touch this field in any way.
915  */
916  void *opaque;
917 
918  /**
919  * This callback may be set by the caller immediately after allocating the
920  * graph and before adding any filters to it, to provide a custom
921  * multithreading implementation.
922  *
923  * If set, filters with slice threading capability will call this callback
924  * to execute multiple jobs in parallel.
925  *
926  * If this field is left unset, libavfilter will use its internal
927  * implementation, which may or may not be multithreaded depending on the
928  * platform and build options.
929  */
931 
932  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
933 
934  /**
935  * Private fields
936  *
937  * The following fields are for internal use only.
938  * Their type, offset, number and semantic can change without notice.
939  */
940 
943 
945 } AVFilterGraph;
946 
947 /**
948  * Allocate a filter graph.
949  *
950  * @return the allocated filter graph on success or NULL.
951  */
953 
954 /**
955  * Create a new filter instance in a filter graph.
956  *
957  * @param graph graph in which the new filter will be used
958  * @param filter the filter to create an instance of
959  * @param name Name to give to the new instance (will be copied to
960  * AVFilterContext.name). This may be used by the caller to identify
961  * different filters, libavfilter itself assigns no semantics to
962  * this parameter. May be NULL.
963  *
964  * @return the context of the newly created filter instance (note that it is
965  * also retrievable directly through AVFilterGraph.filters or with
966  * avfilter_graph_get_filter()) on success or NULL on failure.
967  */
969  const AVFilter *filter,
970  const char *name);
971 
972 /**
973  * Get a filter instance identified by instance name from graph.
974  *
975  * @param graph filter graph to search through.
976  * @param name filter instance name (should be unique in the graph).
977  * @return the pointer to the found filter instance or NULL if it
978  * cannot be found.
979  */
981 
982 /**
983  * Create and add a filter instance into an existing graph.
984  * The filter instance is created from the filter filt and inited
985  * with the parameter args. opaque is currently ignored.
986  *
987  * In case of success put in *filt_ctx the pointer to the created
988  * filter instance, otherwise set *filt_ctx to NULL.
989  *
990  * @param name the instance name to give to the created filter instance
991  * @param graph_ctx the filter graph
992  * @return a negative AVERROR error code in case of failure, a non
993  * negative value otherwise
994  */
996  const char *name, const char *args, void *opaque,
997  AVFilterGraph *graph_ctx);
998 
999 /**
1000  * Enable or disable automatic format conversion inside the graph.
1001  *
1002  * Note that format conversion can still happen inside explicitly inserted
1003  * scale and aresample filters.
1004  *
1005  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
1006  */
1007 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags);
1008 
1009 enum {
1010  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
1011  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
1012 };
1013 
1014 /**
1015  * Check validity and configure all the links and formats in the graph.
1016  *
1017  * @param graphctx the filter graph
1018  * @param log_ctx context used for logging
1019  * @return >= 0 in case of success, a negative AVERROR code otherwise
1020  */
1021 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1022 
1023 /**
1024  * Free a graph, destroy its links, and set *graph to NULL.
1025  * If *graph is NULL, do nothing.
1026  */
1027 void avfilter_graph_free(AVFilterGraph **graph);
1028 
1029 /**
1030  * A linked-list of the inputs/outputs of the filter chain.
1031  *
1032  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1033  * where it is used to communicate open (unlinked) inputs and outputs from and
1034  * to the caller.
1035  * This struct specifies, per each not connected pad contained in the graph, the
1036  * filter context and the pad index required for establishing a link.
1037  */
1038 typedef struct AVFilterInOut {
1039  /** unique name for this input/output in the list */
1040  char *name;
1041 
1042  /** filter context associated to this input/output */
1044 
1045  /** index of the filt_ctx pad to use for linking */
1046  int pad_idx;
1047 
1048  /** next input/input in the list, NULL if this is the last */
1050 } AVFilterInOut;
1051 
1052 /**
1053  * Allocate a single AVFilterInOut entry.
1054  * Must be freed with avfilter_inout_free().
1055  * @return allocated AVFilterInOut on success, NULL on failure.
1056  */
1058 
1059 /**
1060  * Free the supplied list of AVFilterInOut and set *inout to NULL.
1061  * If *inout is NULL, do nothing.
1062  */
1063 void avfilter_inout_free(AVFilterInOut **inout);
1064 
1065 /**
1066  * Add a graph described by a string to a graph.
1067  *
1068  * @note The caller must provide the lists of inputs and outputs,
1069  * which therefore must be known before calling the function.
1070  *
1071  * @note The inputs parameter describes inputs of the already existing
1072  * part of the graph; i.e. from the point of view of the newly created
1073  * part, they are outputs. Similarly the outputs parameter describes
1074  * outputs of the already existing filters, which are provided as
1075  * inputs to the parsed filters.
1076  *
1077  * @param graph the filter graph where to link the parsed graph context
1078  * @param filters string to be parsed
1079  * @param inputs linked list to the inputs of the graph
1080  * @param outputs linked list to the outputs of the graph
1081  * @return zero on success, a negative AVERROR code on error
1082  */
1083 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1085  void *log_ctx);
1086 
1087 /**
1088  * Add a graph described by a string to a graph.
1089  *
1090  * In the graph filters description, if the input label of the first
1091  * filter is not specified, "in" is assumed; if the output label of
1092  * the last filter is not specified, "out" is assumed.
1093  *
1094  * @param graph the filter graph where to link the parsed graph context
1095  * @param filters string to be parsed
1096  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1097  * If non-NULL, *inputs is updated to contain the list of open inputs
1098  * after the parsing, should be freed with avfilter_inout_free().
1099  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1100  * If non-NULL, *outputs is updated to contain the list of open outputs
1101  * after the parsing, should be freed with avfilter_inout_free().
1102  * @return non negative on success, a negative AVERROR code on error
1103  */
1104 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1106  void *log_ctx);
1107 
1108 /**
1109  * Add a graph described by a string to a graph.
1110  *
1111  * @param[in] graph the filter graph where to link the parsed graph context
1112  * @param[in] filters string to be parsed
1113  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1114  * parsed graph will be returned here. It is to be freed
1115  * by the caller using avfilter_inout_free().
1116  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1117  * parsed graph will be returned here. It is to be freed by the
1118  * caller using avfilter_inout_free().
1119  * @return zero on success, a negative AVERROR code on error
1120  *
1121  * @note This function returns the inputs and outputs that are left
1122  * unlinked after parsing the graph and the caller then deals with
1123  * them.
1124  * @note This function makes no reference whatsoever to already
1125  * existing parts of the graph and the inputs parameter will on return
1126  * contain inputs of the newly parsed part of the graph. Analogously
1127  * the outputs parameter will contain outputs of the newly created
1128  * filters.
1129  */
1130 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1133 
1134 /**
1135  * Send a command to 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 send, for handling simplicity all commands must be alphanumeric only
1143  * @param arg the argument for the command
1144  * @param res a buffer with size res_size where the filter(s) can return a response.
1145  *
1146  * @returns >=0 on success otherwise an error code.
1147  * AVERROR(ENOSYS) on unsupported commands
1148  */
1149 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1150 
1151 /**
1152  * Queue a command for one or more filter instances.
1153  *
1154  * @param graph the filter graph
1155  * @param target the filter(s) to which the command should be sent
1156  * "all" sends to all filters
1157  * otherwise it can be a filter or filter instance name
1158  * which will send the command to all matching filters.
1159  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1160  * @param arg the argument for the command
1161  * @param ts time at which the command should be sent to the filter
1162  *
1163  * @note As this executes commands after this function returns, no return code
1164  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1165  */
1166 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1167 
1168 
1169 /**
1170  * Dump a graph into a human-readable string representation.
1171  *
1172  * @param graph the graph to dump
1173  * @param options formatting options; currently ignored
1174  * @return a string, or NULL in case of memory allocation failure;
1175  * the string must be freed using av_free
1176  */
1177 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1178 
1179 /**
1180  * Request a frame on the oldest sink link.
1181  *
1182  * If the request returns AVERROR_EOF, try the next.
1183  *
1184  * Note that this function is not meant to be the sole scheduling mechanism
1185  * of a filtergraph, only a convenience function to help drain a filtergraph
1186  * in a balanced way under normal circumstances.
1187  *
1188  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1189  * some of the sinks during the process.
1190  * When there are multiple sink links, in case the requested link
1191  * returns an EOF, this may cause a filter to flush pending frames
1192  * which are sent to another sink link, although unrequested.
1193  *
1194  * @return the return value of ff_request_frame(),
1195  * or AVERROR_EOF if all links returned AVERROR_EOF
1196  */
1198 
1199 /**
1200  * @}
1201  */
1202 
1203 #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:930
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:478
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:524
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:584
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:904
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:963
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:529
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:347
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:210
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:861
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:461
AVFilter::pix_fmt
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:362
rational.h
AVFilterContext::is_disabled
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:462
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:385
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:1049
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:428
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:416
AVFilterGraph::disable_auto_convert
unsigned disable_auto_convert
Definition: avfilter.h:944
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:471
AVFilterGraphInternal
Definition: internal.h:132
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:32
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:426
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:175
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:119
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: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
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:430
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:432
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:459
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:82
AVFilter::formats_state
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:239
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:241
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:590
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:501
avfilter_config_links
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:278
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:916
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:371
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:49
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
Definition: version.c:40
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:422
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_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:1010
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:358
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:542
filters
#define filters(fmt, type, inverse, clp, inverset, clip, one, clip_fn, packed)
Definition: af_crystalizer.c:55
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:172
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:215
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:932
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
AVFilter::formats
union AVFilter::@217 formats
The state of the following union is determined by formats_state.
arg
const char * arg
Definition: jacosubdec.c:67
AVFilter::activate
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:399
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:601
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:450
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:1167
AVFilter::outputs
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:200
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
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:880
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:423
AVFilterInternal
Definition: internal.h:138
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:420
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:283
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1295
AVFilterGraph
Definition: avfilter.h:878
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:514
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:1046
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:883
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:424
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:879
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:457
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1043
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:875
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:254
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:148
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:1215
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:182
avfilter_link_free
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
Definition: avfilter.c:187
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:228
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:277
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:929
AVFilter::query_func
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:336
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:33
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:897
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:369
AVFilter
Filter definition.
Definition: avfilter.h:171
ret
ret
Definition: filter_design.txt:187
AVFilterGraph::sink_links
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:941
pixfmt.h
avfilter_configuration
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
Definition: version.c:35
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:157
dict.h
AVFilter::nb_outputs
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:233
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:968
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:886
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:460
AVFilterContext
An instance of a filter.
Definition: avfilter.h:415
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:519
AVFilter::inputs
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:191
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:302
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:747
AVFilter::sample_fmt
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:366
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
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:1040
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:1185
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:1011
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:881
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:418
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:290
int
int
Definition: ffmpeg_filter.c:156
avfilter_version
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
Definition: version.c:29
avfilter_get_class
const AVClass * avfilter_get_class(void)
Definition: avfilter.c:1557
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1038
AVFilterGraph::sink_links_count
int sink_links_count
Definition: avfilter.h:942
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:485
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:427