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  * The number of the filter inputs is not determined just by AVFilter.inputs.
103  * The filter might add additional inputs during initialization depending on the
104  * options supplied to it.
105  */
106 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
107 /**
108  * The number of the filter outputs is not determined just by AVFilter.outputs.
109  * The filter might add additional outputs during initialization depending on
110  * the options supplied to it.
111  */
112 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
113 /**
114  * The filter supports multithreading by splitting frames into multiple parts
115  * and processing them concurrently.
116  */
117 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
118 /**
119  * The filter is a "metadata" filter - it does not modify the frame data in any
120  * way. It may only affect the metadata (i.e. those fields copied by
121  * av_frame_copy_props()).
122  *
123  * More precisely, this means:
124  * - video: the data of any frame output by the filter must be exactly equal to
125  * some frame that is received on one of its inputs. Furthermore, all frames
126  * produced on a given output must correspond to frames received on the same
127  * input and their order must be unchanged. Note that the filter may still
128  * drop or duplicate the frames.
129  * - audio: the data produced by the filter on any of its outputs (viewed e.g.
130  * as an array of interleaved samples) must be exactly equal to the data
131  * received by the filter on one of its inputs.
132  */
133 #define AVFILTER_FLAG_METADATA_ONLY (1 << 3)
134 
135 /**
136  * The filter can create hardware frames using AVFilterContext.hw_device_ctx.
137  */
138 #define AVFILTER_FLAG_HWDEVICE (1 << 4)
139 /**
140  * Some filters support a generic "enable" expression option that can be used
141  * to enable or disable a filter in the timeline. Filters supporting this
142  * option have this flag set. When the enable expression is false, the default
143  * no-op filter_frame() function is called in place of the filter_frame()
144  * callback defined on each input pad, thus the frame is passed unchanged to
145  * the next filters.
146  */
147 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
148 /**
149  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
150  * have its filter_frame() callback(s) called as usual even when the enable
151  * expression is false. The filter will disable filtering within the
152  * filter_frame() callback(s) itself, for example executing code depending on
153  * the AVFilterContext->is_disabled value.
154  */
155 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
156 /**
157  * Handy mask to test whether the filter supports or no the timeline feature
158  * (internally or generically).
159  */
160 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
161 
162 /**
163  * Filter definition. This defines the pads a filter contains, and all the
164  * callback functions used to interact with the filter.
165  */
166 typedef struct AVFilter {
167  /**
168  * Filter name. Must be non-NULL and unique among filters.
169  */
170  const char *name;
171 
172  /**
173  * A description of the filter. May be NULL.
174  *
175  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
176  */
177  const char *description;
178 
179  /**
180  * List of static inputs.
181  *
182  * NULL if there are no (static) inputs. Instances of filters with
183  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
184  * this list.
185  */
187 
188  /**
189  * List of static outputs.
190  *
191  * NULL if there are no (static) outputs. Instances of filters with
192  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
193  * this list.
194  */
196 
197  /**
198  * A class for the private data, used to declare filter private AVOptions.
199  * This field is NULL for filters that do not declare any options.
200  *
201  * If this field is non-NULL, the first member of the filter private data
202  * must be a pointer to AVClass, which will be set by libavfilter generic
203  * code to this class.
204  */
206 
207  /**
208  * A combination of AVFILTER_FLAG_*
209  */
210  int flags;
211 
212  /*****************************************************************
213  * All fields below this line are not part of the public API. They
214  * may not be used outside of libavfilter and can be changed and
215  * removed at will.
216  * New public fields should be added right above.
217  *****************************************************************
218  */
219 
220  /**
221  * The number of entries in the list of inputs.
222  */
223  uint8_t nb_inputs;
224 
225  /**
226  * The number of entries in the list of outputs.
227  */
228  uint8_t nb_outputs;
229 
230  /**
231  * This field determines the state of the formats union.
232  * It is an enum FilterFormatsState value.
233  */
234  uint8_t formats_state;
235 
236  /**
237  * Filter pre-initialization function
238  *
239  * This callback will be called immediately after the filter context is
240  * allocated, to allow allocating and initing sub-objects.
241  *
242  * If this callback is not NULL, the uninit callback will be called on
243  * allocation failure.
244  *
245  * @return 0 on success,
246  * AVERROR code on failure (but the code will be
247  * dropped and treated as ENOMEM by the calling code)
248  */
250 
251  /**
252  * Filter initialization function.
253  *
254  * This callback will be called only once during the filter lifetime, after
255  * all the options have been set, but before links between filters are
256  * established and format negotiation is done.
257  *
258  * Basic filter initialization should be done here. Filters with dynamic
259  * inputs and/or outputs should create those inputs/outputs here based on
260  * provided options. No more changes to this filter's inputs/outputs can be
261  * done after this callback.
262  *
263  * This callback must not assume that the filter links exist or frame
264  * parameters are known.
265  *
266  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
267  * initialization fails, so this callback does not have to clean up on
268  * failure.
269  *
270  * @return 0 on success, a negative AVERROR on failure
271  */
273 
274  /**
275  * Filter uninitialization function.
276  *
277  * Called only once right before the filter is freed. Should deallocate any
278  * memory held by the filter, release any buffer references, etc. It does
279  * not need to deallocate the AVFilterContext.priv memory itself.
280  *
281  * This callback may be called even if @ref AVFilter.init "init" was not
282  * called or failed, so it must be prepared to handle such a situation.
283  */
285 
286  /**
287  * The state of the following union is determined by formats_state.
288  * See the documentation of enum FilterFormatsState in internal.h.
289  */
290  union {
291  /**
292  * Query formats supported by the filter on its inputs and outputs.
293  *
294  * This callback is called after the filter is initialized (so the inputs
295  * and outputs are fixed), shortly before the format negotiation. This
296  * callback may be called more than once.
297  *
298  * This callback must set ::AVFilterLink's
299  * @ref AVFilterFormatsConfig.formats "outcfg.formats"
300  * on every input link and
301  * @ref AVFilterFormatsConfig.formats "incfg.formats"
302  * on every output link to a list of pixel/sample formats that the filter
303  * supports on that link.
304  * For video links, this filter may also set
305  * @ref AVFilterFormatsConfig.color_spaces "incfg.color_spaces"
306  * /
307  * @ref AVFilterFormatsConfig.color_spaces "outcfg.color_spaces"
308  * and @ref AVFilterFormatsConfig.color_ranges "incfg.color_ranges"
309  * /
310  * @ref AVFilterFormatsConfig.color_ranges "outcfg.color_ranges"
311  * analogously.
312  * For audio links, this filter must also set
313  * @ref AVFilterFormatsConfig.samplerates "incfg.samplerates"
314  * /
315  * @ref AVFilterFormatsConfig.samplerates "outcfg.samplerates"
316  * and @ref AVFilterFormatsConfig.channel_layouts "incfg.channel_layouts"
317  * /
318  * @ref AVFilterFormatsConfig.channel_layouts "outcfg.channel_layouts"
319  * analogously.
320  *
321  * This callback must never be NULL if the union is in this state.
322  *
323  * @return zero on success, a negative value corresponding to an
324  * AVERROR code otherwise
325  */
327  /**
328  * A pointer to an array of admissible pixel formats delimited
329  * by AV_PIX_FMT_NONE. The generic code will use this list
330  * to indicate that this filter supports each of these pixel formats,
331  * provided that all inputs and outputs use the same pixel format.
332  *
333  * In addition to that the generic code will mark all inputs
334  * and all outputs as supporting all color spaces and ranges, as
335  * long as all inputs and outputs use the same color space/range.
336  *
337  * This list must never be NULL if the union is in this state.
338  * The type of all inputs and outputs of filters using this must
339  * be AVMEDIA_TYPE_VIDEO.
340  */
342  /**
343  * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
344  * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
345  * inputs and outputs.
346  *
347  * In addition to that the generic code will mark all inputs
348  * and all outputs as supporting all sample rates and every
349  * channel count and channel layout, as long as all inputs
350  * and outputs use the same sample rate and channel count/layout.
351  */
353  /**
354  * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
355  */
357  /**
358  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
359  */
361  } formats;
362 
363  int priv_size; ///< size of private data to allocate for the filter
364 
365  int flags_internal; ///< Additional flags for avfilter internal use only.
366 
367  /**
368  * Make the filter instance process a command.
369  *
370  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
371  * @param arg the argument for the command
372  * @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.
373  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
374  * time consuming then a filter should treat it like an unsupported command
375  *
376  * @returns >=0 on success otherwise an error code.
377  * AVERROR(ENOSYS) on unsupported commands
378  */
379  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
380 
381  /**
382  * Filter activation function.
383  *
384  * Called when any processing is needed from the filter, instead of any
385  * filter_frame and request_frame on pads.
386  *
387  * The function must examine inlinks and outlinks and perform a single
388  * step of processing. If there is nothing to do, the function must do
389  * nothing and not return an error. If more steps are or may be
390  * possible, it must use ff_filter_set_ready() to schedule another
391  * activation.
392  */
394 } AVFilter;
395 
396 /**
397  * Get the number of elements in an AVFilter's inputs or outputs array.
398  */
399 unsigned avfilter_filter_pad_count(const AVFilter *filter, int is_output);
400 
401 /**
402  * Process multiple parts of the frame concurrently.
403  */
404 #define AVFILTER_THREAD_SLICE (1 << 0)
405 
406 /** An instance of a filter */
408  const AVClass *av_class; ///< needed for av_log() and filters common options
409 
410  const AVFilter *filter; ///< the AVFilter of which this is an instance
411 
412  char *name; ///< name of this filter instance
413 
414  AVFilterPad *input_pads; ///< array of input pads
415  AVFilterLink **inputs; ///< array of pointers to input links
416  unsigned nb_inputs; ///< number of input pads
417 
418  AVFilterPad *output_pads; ///< array of output pads
419  AVFilterLink **outputs; ///< array of pointers to output links
420  unsigned nb_outputs; ///< number of output pads
421 
422  void *priv; ///< private data for use by the filter
423 
424  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
425 
426  /**
427  * Type of multithreading being allowed/used. A combination of
428  * AVFILTER_THREAD_* flags.
429  *
430  * May be set by the caller before initializing the filter to forbid some
431  * or all kinds of multithreading for this filter. The default is allowing
432  * everything.
433  *
434  * When the filter is initialized, this field is combined using bit AND with
435  * AVFilterGraph.thread_type to get the final mask used for determining
436  * allowed threading types. I.e. a threading type needs to be set in both
437  * to be allowed.
438  *
439  * After the filter is initialized, libavfilter sets this field to the
440  * threading type that is actually used (0 for no multithreading).
441  */
443 
444  /**
445  * Max number of threads allowed in this filter instance.
446  * If <= 0, its value is ignored.
447  * Overrides global number of threads set per filter graph.
448  */
450 
452 
453  char *enable_str; ///< enable expression string
454  void *enable; ///< parsed expression (AVExpr*)
455  double *var_values; ///< variable values for the enable expression
456  int is_disabled; ///< the enabled state from the last expression evaluation
457 
458  /**
459  * For filters which will create hardware frames, sets the device the
460  * filter should create them in. All other filters will ignore this field:
461  * in particular, a filter which consumes or processes hardware frames will
462  * instead use the hw_frames_ctx field in AVFilterLink to carry the
463  * hardware context information.
464  *
465  * May be set by the caller on filters flagged with AVFILTER_FLAG_HWDEVICE
466  * before initializing the filter with avfilter_init_str() or
467  * avfilter_init_dict().
468  */
470 
471  /**
472  * Ready status of the filter.
473  * A non-0 value means that the filter needs activating;
474  * a higher value suggests a more urgent activation.
475  */
476  unsigned ready;
477 
478  /**
479  * Sets the number of extra hardware frames which the filter will
480  * allocate on its output links for use in following filters or by
481  * the caller.
482  *
483  * Some hardware filters require all frames that they will use for
484  * output to be defined in advance before filtering starts. For such
485  * filters, any hardware frame pools used for output must therefore be
486  * of fixed size. The extra frames set here are on top of any number
487  * that the filter needs internally in order to operate normally.
488  *
489  * This field must be set before the graph containing this filter is
490  * configured.
491  */
493 };
494 
495 /**
496  * Lists of formats / etc. supported by an end of a link.
497  *
498  * This structure is directly part of AVFilterLink, in two copies:
499  * one for the source filter, one for the destination filter.
500 
501  * These lists are used for negotiating the format to actually be used,
502  * which will be loaded into the format and channel_layout members of
503  * AVFilterLink, when chosen.
504  */
505 typedef struct AVFilterFormatsConfig {
506 
507  /**
508  * List of supported formats (pixel or sample).
509  */
511 
512  /**
513  * Lists of supported sample rates, only for audio.
514  */
516 
517  /**
518  * Lists of supported channel layouts, only for audio.
519  */
521 
522  /**
523  * Lists of supported YUV color metadata, only for YUV video.
524  */
525  AVFilterFormats *color_spaces; ///< AVColorSpace
526  AVFilterFormats *color_ranges; ///< AVColorRange
527 
529 
530 /**
531  * A link between two filters. This contains pointers to the source and
532  * destination filters between which this link exists, and the indexes of
533  * the pads involved. In addition, this link also contains the parameters
534  * which have been negotiated and agreed upon between the filter, such as
535  * image dimensions, format, etc.
536  *
537  * Applications must not normally access the link structure directly.
538  * Use the buffersrc and buffersink API instead.
539  * In the future, access to the header may be reserved for filters
540  * implementation.
541  */
542 struct AVFilterLink {
543  AVFilterContext *src; ///< source filter
544  AVFilterPad *srcpad; ///< output pad on the source filter
545 
546  AVFilterContext *dst; ///< dest filter
547  AVFilterPad *dstpad; ///< input pad on the dest filter
548 
549  enum AVMediaType type; ///< filter media type
550 
551  int format; ///< agreed upon media format
552 
553  /* These parameters apply only to video */
554  int w; ///< agreed upon image width
555  int h; ///< agreed upon image height
556  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
557  /**
558  * For non-YUV links, these are respectively set to fallback values (as
559  * appropriate for that colorspace).
560  *
561  * Note: This includes grayscale formats, as these are currently treated
562  * as forced full range always.
563  */
564  enum AVColorSpace colorspace; ///< agreed upon YUV color space
565  enum AVColorRange color_range; ///< agreed upon YUV color range
566 
567  /* These parameters apply only to audio */
568  int sample_rate; ///< samples per second
569  AVChannelLayout ch_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
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  /*****************************************************************
581  * All fields below this line are not part of the public API. They
582  * may not be used outside of libavfilter and can be changed and
583  * removed at will.
584  * New public fields should be added right above.
585  *****************************************************************
586  */
587 
588  /**
589  * Lists of supported formats / etc. supported by the input filter.
590  */
592 
593  /**
594  * Lists of supported formats / etc. supported by the output filter.
595  */
597 
598  /**
599  * Graph the filter belongs to.
600  */
602 
603  /**
604  * Current timestamp of the link, as defined by the most recent
605  * frame(s), in link time_base units.
606  */
607  int64_t current_pts;
608 
609  /**
610  * Current timestamp of the link, as defined by the most recent
611  * frame(s), in AV_TIME_BASE units.
612  */
613  int64_t current_pts_us;
614 
615  /**
616  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
617  * if left to 0/0, will be automatically copied from the first input
618  * of the source filter if it exists.
619  *
620  * Sources should set it to the best estimation of the real frame rate.
621  * If the source frame rate is unknown or variable, set this to 1/0.
622  * Filters should update it if necessary depending on their function.
623  * Sinks can use it to set a default output frame rate.
624  * It is similar to the r_frame_rate field in AVStream.
625  */
627 
628  /**
629  * Minimum number of samples to filter at once. If filter_frame() is
630  * called with fewer samples, it will accumulate them in fifo.
631  * This field and the related ones must not be changed after filtering
632  * has started.
633  * If 0, all related fields are ignored.
634  */
636 
637  /**
638  * Maximum number of samples to filter at once. If filter_frame() is
639  * called with more samples, it will split them.
640  */
642 
643  /**
644  * Number of past frames sent through the link.
645  */
647 
648  /**
649  * Number of past samples sent through the link.
650  */
652 
653  /**
654  * True if a frame is currently wanted on the output of this filter.
655  * Set when ff_request_frame() is called by the output,
656  * cleared when a frame is filtered.
657  */
659 
660  /**
661  * For hwaccel pixel formats, this should be a reference to the
662  * AVHWFramesContext describing the frames.
663  */
665 };
666 
667 /**
668  * Link two filters together.
669  *
670  * @param src the source filter
671  * @param srcpad index of the output pad on the source filter
672  * @param dst the destination filter
673  * @param dstpad index of the input pad on the destination filter
674  * @return zero on success
675  */
676 int avfilter_link(AVFilterContext *src, unsigned srcpad,
677  AVFilterContext *dst, unsigned dstpad);
678 
679 #if FF_API_LINK_PUBLIC
680 /**
681  * @deprecated this function should never be called by users
682  */
684 void avfilter_link_free(AVFilterLink **link);
685 
686 /**
687  * @deprecated this function should never be called by users
688  */
690 int avfilter_config_links(AVFilterContext *filter);
691 #endif
692 
693 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
694 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
695 
696 /**
697  * Make the filter instance process a command.
698  * It is recommended to use avfilter_graph_send_command().
699  */
700 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
701 
702 /**
703  * Iterate over all registered filters.
704  *
705  * @param opaque a pointer where libavfilter will store the iteration state. Must
706  * point to NULL to start the iteration.
707  *
708  * @return the next registered filter or NULL when the iteration is
709  * finished
710  */
711 const AVFilter *av_filter_iterate(void **opaque);
712 
713 /**
714  * Get a filter definition matching the given name.
715  *
716  * @param name the filter name to find
717  * @return the filter definition, if any matching one is registered.
718  * NULL if none found.
719  */
720 const AVFilter *avfilter_get_by_name(const char *name);
721 
722 
723 /**
724  * Initialize a filter with the supplied parameters.
725  *
726  * @param ctx uninitialized filter context to initialize
727  * @param args Options to initialize the filter with. This must be a
728  * ':'-separated list of options in the 'key=value' form.
729  * May be NULL if the options have been set directly using the
730  * AVOptions API or there are no options that need to be set.
731  * @return 0 on success, a negative AVERROR on failure
732  */
733 int avfilter_init_str(AVFilterContext *ctx, const char *args);
734 
735 /**
736  * Initialize a filter with the supplied dictionary of options.
737  *
738  * @param ctx uninitialized filter context to initialize
739  * @param options An AVDictionary filled with options for this filter. On
740  * return this parameter will be destroyed and replaced with
741  * a dict containing options that were not found. This dictionary
742  * must be freed by the caller.
743  * May be NULL, then this function is equivalent to
744  * avfilter_init_str() with the second parameter set to NULL.
745  * @return 0 on success, a negative AVERROR on failure
746  *
747  * @note This function and avfilter_init_str() do essentially the same thing,
748  * the difference is in manner in which the options are passed. It is up to the
749  * calling code to choose whichever is more preferable. The two functions also
750  * behave differently when some of the provided options are not declared as
751  * supported by the filter. In such a case, avfilter_init_str() will fail, but
752  * this function will leave those extra options in the options AVDictionary and
753  * continue as usual.
754  */
756 
757 /**
758  * Free a filter context. This will also remove the filter from its
759  * filtergraph's list of filters.
760  *
761  * @param filter the filter to free
762  */
764 
765 /**
766  * Insert a filter in the middle of an existing link.
767  *
768  * @param link the link into which the filter should be inserted
769  * @param filt the filter to be inserted
770  * @param filt_srcpad_idx the input pad on the filter to connect
771  * @param filt_dstpad_idx the output pad on the filter to connect
772  * @return zero on success
773  */
775  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
776 
777 /**
778  * @return AVClass for AVFilterContext.
779  *
780  * @see av_opt_find().
781  */
782 const AVClass *avfilter_get_class(void);
783 
784 /**
785  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
786  * executed multiple times, possibly in parallel.
787  *
788  * @param ctx the filter context the job belongs to
789  * @param arg an opaque parameter passed through from @ref
790  * AVFilterGraph.execute
791  * @param jobnr the index of the job being executed
792  * @param nb_jobs the total number of jobs
793  *
794  * @return 0 on success, a negative AVERROR on error
795  */
796 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
797 
798 /**
799  * A function executing multiple jobs, possibly in parallel.
800  *
801  * @param ctx the filter context to which the jobs belong
802  * @param func the function to be called multiple times
803  * @param arg the argument to be passed to func
804  * @param ret a nb_jobs-sized array to be filled with return values from each
805  * invocation of func
806  * @param nb_jobs the number of jobs to execute
807  *
808  * @return 0 on success, a negative AVERROR on error
809  */
811  void *arg, int *ret, int nb_jobs);
812 
813 typedef struct AVFilterGraph {
816  unsigned nb_filters;
817 
818  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
819 
820  /**
821  * Type of multithreading allowed for filters in this graph. A combination
822  * of AVFILTER_THREAD_* flags.
823  *
824  * May be set by the caller at any point, the setting will apply to all
825  * filters initialized after that. The default is allowing everything.
826  *
827  * When a filter in this graph is initialized, this field is combined using
828  * bit AND with AVFilterContext.thread_type to get the final mask used for
829  * determining allowed threading types. I.e. a threading type needs to be
830  * set in both to be allowed.
831  */
833 
834  /**
835  * Maximum number of threads used by filters in this graph. May be set by
836  * the caller before adding any filters to the filtergraph. Zero (the
837  * default) means that the number of threads is determined automatically.
838  */
840 
841  /**
842  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
843  * be used from callbacks like @ref AVFilterGraph.execute.
844  * Libavfilter will not touch this field in any way.
845  */
846  void *opaque;
847 
848  /**
849  * This callback may be set by the caller immediately after allocating the
850  * graph and before adding any filters to it, to provide a custom
851  * multithreading implementation.
852  *
853  * If set, filters with slice threading capability will call this callback
854  * to execute multiple jobs in parallel.
855  *
856  * If this field is left unset, libavfilter will use its internal
857  * implementation, which may or may not be multithreaded depending on the
858  * platform and build options.
859  */
861 
862  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
863 } AVFilterGraph;
864 
865 /**
866  * Allocate a filter graph.
867  *
868  * @return the allocated filter graph on success or NULL.
869  */
871 
872 /**
873  * Create a new filter instance in a filter graph.
874  *
875  * @param graph graph in which the new filter will be used
876  * @param filter the filter to create an instance of
877  * @param name Name to give to the new instance (will be copied to
878  * AVFilterContext.name). This may be used by the caller to identify
879  * different filters, libavfilter itself assigns no semantics to
880  * this parameter. May be NULL.
881  *
882  * @return the context of the newly created filter instance (note that it is
883  * also retrievable directly through AVFilterGraph.filters or with
884  * avfilter_graph_get_filter()) on success or NULL on failure.
885  */
887  const AVFilter *filter,
888  const char *name);
889 
890 /**
891  * Get a filter instance identified by instance name from graph.
892  *
893  * @param graph filter graph to search through.
894  * @param name filter instance name (should be unique in the graph).
895  * @return the pointer to the found filter instance or NULL if it
896  * cannot be found.
897  */
899 
900 /**
901  * Create and add a filter instance into an existing graph.
902  * The filter instance is created from the filter filt and inited
903  * with the parameter args. opaque is currently ignored.
904  *
905  * In case of success put in *filt_ctx the pointer to the created
906  * filter instance, otherwise set *filt_ctx to NULL.
907  *
908  * @param name the instance name to give to the created filter instance
909  * @param graph_ctx the filter graph
910  * @return a negative AVERROR error code in case of failure, a non
911  * negative value otherwise
912  */
914  const char *name, const char *args, void *opaque,
915  AVFilterGraph *graph_ctx);
916 
917 /**
918  * Enable or disable automatic format conversion inside the graph.
919  *
920  * Note that format conversion can still happen inside explicitly inserted
921  * scale and aresample filters.
922  *
923  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
924  */
926 
927 enum {
928  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
929  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
930 };
931 
932 /**
933  * Check validity and configure all the links and formats in the graph.
934  *
935  * @param graphctx the filter graph
936  * @param log_ctx context used for logging
937  * @return >= 0 in case of success, a negative AVERROR code otherwise
938  */
939 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
940 
941 /**
942  * Free a graph, destroy its links, and set *graph to NULL.
943  * If *graph is NULL, do nothing.
944  */
945 void avfilter_graph_free(AVFilterGraph **graph);
946 
947 /**
948  * A linked-list of the inputs/outputs of the filter chain.
949  *
950  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
951  * where it is used to communicate open (unlinked) inputs and outputs from and
952  * to the caller.
953  * This struct specifies, per each not connected pad contained in the graph, the
954  * filter context and the pad index required for establishing a link.
955  */
956 typedef struct AVFilterInOut {
957  /** unique name for this input/output in the list */
958  char *name;
959 
960  /** filter context associated to this input/output */
962 
963  /** index of the filt_ctx pad to use for linking */
964  int pad_idx;
965 
966  /** next input/input in the list, NULL if this is the last */
968 } AVFilterInOut;
969 
970 /**
971  * Allocate a single AVFilterInOut entry.
972  * Must be freed with avfilter_inout_free().
973  * @return allocated AVFilterInOut on success, NULL on failure.
974  */
976 
977 /**
978  * Free the supplied list of AVFilterInOut and set *inout to NULL.
979  * If *inout is NULL, do nothing.
980  */
981 void avfilter_inout_free(AVFilterInOut **inout);
982 
983 /**
984  * Add a graph described by a string to a graph.
985  *
986  * @note The caller must provide the lists of inputs and outputs,
987  * which therefore must be known before calling the function.
988  *
989  * @note The inputs parameter describes inputs of the already existing
990  * part of the graph; i.e. from the point of view of the newly created
991  * part, they are outputs. Similarly the outputs parameter describes
992  * outputs of the already existing filters, which are provided as
993  * inputs to the parsed filters.
994  *
995  * @param graph the filter graph where to link the parsed graph context
996  * @param filters string to be parsed
997  * @param inputs linked list to the inputs of the graph
998  * @param outputs linked list to the outputs of the graph
999  * @return zero on success, a negative AVERROR code on error
1000  */
1001 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1003  void *log_ctx);
1004 
1005 /**
1006  * Add a graph described by a string to a graph.
1007  *
1008  * In the graph filters description, if the input label of the first
1009  * filter is not specified, "in" is assumed; if the output label of
1010  * the last filter is not specified, "out" is assumed.
1011  *
1012  * @param graph the filter graph where to link the parsed graph context
1013  * @param filters string to be parsed
1014  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1015  * If non-NULL, *inputs is updated to contain the list of open inputs
1016  * after the parsing, should be freed with avfilter_inout_free().
1017  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1018  * If non-NULL, *outputs is updated to contain the list of open outputs
1019  * after the parsing, should be freed with avfilter_inout_free().
1020  * @return non negative on success, a negative AVERROR code on error
1021  */
1022 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1024  void *log_ctx);
1025 
1026 /**
1027  * Add a graph described by a string to a graph.
1028  *
1029  * @param[in] graph the filter graph where to link the parsed graph context
1030  * @param[in] filters string to be parsed
1031  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1032  * parsed graph will be returned here. It is to be freed
1033  * by the caller using avfilter_inout_free().
1034  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1035  * parsed graph will be returned here. It is to be freed by the
1036  * caller using avfilter_inout_free().
1037  * @return zero on success, a negative AVERROR code on error
1038  *
1039  * @note This function returns the inputs and outputs that are left
1040  * unlinked after parsing the graph and the caller then deals with
1041  * them.
1042  * @note This function makes no reference whatsoever to already
1043  * existing parts of the graph and the inputs parameter will on return
1044  * contain inputs of the newly parsed part of the graph. Analogously
1045  * the outputs parameter will contain outputs of the newly created
1046  * filters.
1047  */
1048 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1051 
1052 /**
1053  * Parameters of a filter's input or output pad.
1054  *
1055  * Created as a child of AVFilterParams by avfilter_graph_segment_parse().
1056  * Freed in avfilter_graph_segment_free().
1057  */
1058 typedef struct AVFilterPadParams {
1059  /**
1060  * An av_malloc()'ed string containing the pad label.
1061  *
1062  * May be av_free()'d and set to NULL by the caller, in which case this pad
1063  * will be treated as unlabeled for linking.
1064  * May also be replaced by another av_malloc()'ed string.
1065  */
1066  char *label;
1068 
1069 /**
1070  * Parameters describing a filter to be created in a filtergraph.
1071  *
1072  * Created as a child of AVFilterGraphSegment by avfilter_graph_segment_parse().
1073  * Freed in avfilter_graph_segment_free().
1074  */
1075 typedef struct AVFilterParams {
1076  /**
1077  * The filter context.
1078  *
1079  * Created by avfilter_graph_segment_create_filters() based on
1080  * AVFilterParams.filter_name and instance_name.
1081  *
1082  * Callers may also create the filter context manually, then they should
1083  * av_free() filter_name and set it to NULL. Such AVFilterParams instances
1084  * are then skipped by avfilter_graph_segment_create_filters().
1085  */
1087 
1088  /**
1089  * Name of the AVFilter to be used.
1090  *
1091  * An av_malloc()'ed string, set by avfilter_graph_segment_parse(). Will be
1092  * passed to avfilter_get_by_name() by
1093  * avfilter_graph_segment_create_filters().
1094  *
1095  * Callers may av_free() this string and replace it with another one or
1096  * NULL. If the caller creates the filter instance manually, this string
1097  * MUST be set to NULL.
1098  *
1099  * When both AVFilterParams.filter an AVFilterParams.filter_name are NULL,
1100  * this AVFilterParams instance is skipped by avfilter_graph_segment_*()
1101  * functions.
1102  */
1104  /**
1105  * Name to be used for this filter instance.
1106  *
1107  * An av_malloc()'ed string, may be set by avfilter_graph_segment_parse() or
1108  * left NULL. The caller may av_free() this string and replace with another
1109  * one or NULL.
1110  *
1111  * Will be used by avfilter_graph_segment_create_filters() - passed as the
1112  * third argument to avfilter_graph_alloc_filter(), then freed and set to
1113  * NULL.
1114  */
1116 
1117  /**
1118  * Options to be apllied to the filter.
1119  *
1120  * Filled by avfilter_graph_segment_parse(). Afterwards may be freely
1121  * modified by the caller.
1122  *
1123  * Will be applied to the filter by avfilter_graph_segment_apply_opts()
1124  * with an equivalent of av_opt_set_dict2(filter, &opts, AV_OPT_SEARCH_CHILDREN),
1125  * i.e. any unapplied options will be left in this dictionary.
1126  */
1128 
1130  unsigned nb_inputs;
1131 
1133  unsigned nb_outputs;
1134 } AVFilterParams;
1135 
1136 /**
1137  * A filterchain is a list of filter specifications.
1138  *
1139  * Created as a child of AVFilterGraphSegment by avfilter_graph_segment_parse().
1140  * Freed in avfilter_graph_segment_free().
1141  */
1142 typedef struct AVFilterChain {
1144  size_t nb_filters;
1145 } AVFilterChain;
1146 
1147 /**
1148  * A parsed representation of a filtergraph segment.
1149  *
1150  * A filtergraph segment is conceptually a list of filterchains, with some
1151  * supplementary information (e.g. format conversion flags).
1152  *
1153  * Created by avfilter_graph_segment_parse(). Must be freed with
1154  * avfilter_graph_segment_free().
1155  */
1156 typedef struct AVFilterGraphSegment {
1157  /**
1158  * The filtergraph this segment is associated with.
1159  * Set by avfilter_graph_segment_parse().
1160  */
1162 
1163  /**
1164  * A list of filter chain contained in this segment.
1165  * Set in avfilter_graph_segment_parse().
1166  */
1168  size_t nb_chains;
1169 
1170  /**
1171  * A string containing a colon-separated list of key=value options applied
1172  * to all scale filters in this segment.
1173  *
1174  * May be set by avfilter_graph_segment_parse().
1175  * The caller may free this string with av_free() and replace it with a
1176  * different av_malloc()'ed string.
1177  */
1180 
1181 /**
1182  * Parse a textual filtergraph description into an intermediate form.
1183  *
1184  * This intermediate representation is intended to be modified by the caller as
1185  * described in the documentation of AVFilterGraphSegment and its children, and
1186  * then applied to the graph either manually or with other
1187  * avfilter_graph_segment_*() functions. See the documentation for
1188  * avfilter_graph_segment_apply() for the canonical way to apply
1189  * AVFilterGraphSegment.
1190  *
1191  * @param graph Filter graph the parsed segment is associated with. Will only be
1192  * used for logging and similar auxiliary purposes. The graph will
1193  * not be actually modified by this function - the parsing results
1194  * are instead stored in seg for further processing.
1195  * @param graph_str a string describing the filtergraph segment
1196  * @param flags reserved for future use, caller must set to 0 for now
1197  * @param seg A pointer to the newly-created AVFilterGraphSegment is written
1198  * here on success. The graph segment is owned by the caller and must
1199  * be freed with avfilter_graph_segment_free() before graph itself is
1200  * freed.
1201  *
1202  * @retval "non-negative number" success
1203  * @retval "negative error code" failure
1204  */
1205 int avfilter_graph_segment_parse(AVFilterGraph *graph, const char *graph_str,
1206  int flags, AVFilterGraphSegment **seg);
1207 
1208 /**
1209  * Create filters specified in a graph segment.
1210  *
1211  * Walk through the creation-pending AVFilterParams in the segment and create
1212  * new filter instances for them.
1213  * Creation-pending params are those where AVFilterParams.filter_name is
1214  * non-NULL (and hence AVFilterParams.filter is NULL). All other AVFilterParams
1215  * instances are ignored.
1216  *
1217  * For any filter created by this function, the corresponding
1218  * AVFilterParams.filter is set to the newly-created filter context,
1219  * AVFilterParams.filter_name and AVFilterParams.instance_name are freed and set
1220  * to NULL.
1221  *
1222  * @param seg the filtergraph segment to process
1223  * @param flags reserved for future use, caller must set to 0 for now
1224  *
1225  * @retval "non-negative number" Success, all creation-pending filters were
1226  * successfully created
1227  * @retval AVERROR_FILTER_NOT_FOUND some filter's name did not correspond to a
1228  * known filter
1229  * @retval "another negative error code" other failures
1230  *
1231  * @note Calling this function multiple times is safe, as it is idempotent.
1232  */
1234 
1235 /**
1236  * Apply parsed options to filter instances in a graph segment.
1237  *
1238  * Walk through all filter instances in the graph segment that have option
1239  * dictionaries associated with them and apply those options with
1240  * av_opt_set_dict2(..., AV_OPT_SEARCH_CHILDREN). AVFilterParams.opts is
1241  * replaced by the dictionary output by av_opt_set_dict2(), which should be
1242  * empty (NULL) if all options were successfully applied.
1243  *
1244  * If any options could not be found, this function will continue processing all
1245  * other filters and finally return AVERROR_OPTION_NOT_FOUND (unless another
1246  * error happens). The calling program may then deal with unapplied options as
1247  * it wishes.
1248  *
1249  * Any creation-pending filters (see avfilter_graph_segment_create_filters())
1250  * present in the segment will cause this function to fail. AVFilterParams with
1251  * no associated filter context are simply skipped.
1252  *
1253  * @param seg the filtergraph segment to process
1254  * @param flags reserved for future use, caller must set to 0 for now
1255  *
1256  * @retval "non-negative number" Success, all options were successfully applied.
1257  * @retval AVERROR_OPTION_NOT_FOUND some options were not found in a filter
1258  * @retval "another negative error code" other failures
1259  *
1260  * @note Calling this function multiple times is safe, as it is idempotent.
1261  */
1263 
1264 /**
1265  * Initialize all filter instances in a graph segment.
1266  *
1267  * Walk through all filter instances in the graph segment and call
1268  * avfilter_init_dict(..., NULL) on those that have not been initialized yet.
1269  *
1270  * Any creation-pending filters (see avfilter_graph_segment_create_filters())
1271  * present in the segment will cause this function to fail. AVFilterParams with
1272  * no associated filter context or whose filter context is already initialized,
1273  * are simply skipped.
1274  *
1275  * @param seg the filtergraph segment to process
1276  * @param flags reserved for future use, caller must set to 0 for now
1277  *
1278  * @retval "non-negative number" Success, all filter instances were successfully
1279  * initialized
1280  * @retval "negative error code" failure
1281  *
1282  * @note Calling this function multiple times is safe, as it is idempotent.
1283  */
1285 
1286 /**
1287  * Link filters in a graph segment.
1288  *
1289  * Walk through all filter instances in the graph segment and try to link all
1290  * unlinked input and output pads. Any creation-pending filters (see
1291  * avfilter_graph_segment_create_filters()) present in the segment will cause
1292  * this function to fail. Disabled filters and already linked pads are skipped.
1293  *
1294  * Every filter output pad that has a corresponding AVFilterPadParams with a
1295  * non-NULL label is
1296  * - linked to the input with the matching label, if one exists;
1297  * - exported in the outputs linked list otherwise, with the label preserved.
1298  * Unlabeled outputs are
1299  * - linked to the first unlinked unlabeled input in the next non-disabled
1300  * filter in the chain, if one exists
1301  * - exported in the ouputs linked list otherwise, with NULL label
1302  *
1303  * Similarly, unlinked input pads are exported in the inputs linked list.
1304  *
1305  * @param seg the filtergraph segment to process
1306  * @param flags reserved for future use, caller must set to 0 for now
1307  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1308  * filters in this graph segment will be returned here. It
1309  * is to be freed by the caller using avfilter_inout_free().
1310  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1311  * filters in this graph segment will be returned here. It
1312  * is to be freed by the caller using avfilter_inout_free().
1313  *
1314  * @retval "non-negative number" success
1315  * @retval "negative error code" failure
1316  *
1317  * @note Calling this function multiple times is safe, as it is idempotent.
1318  */
1322 
1323 /**
1324  * Apply all filter/link descriptions from a graph segment to the associated filtergraph.
1325  *
1326  * This functions is currently equivalent to calling the following in sequence:
1327  * - avfilter_graph_segment_create_filters();
1328  * - avfilter_graph_segment_apply_opts();
1329  * - avfilter_graph_segment_init();
1330  * - avfilter_graph_segment_link();
1331  * failing if any of them fails. This list may be extended in the future.
1332  *
1333  * Since the above functions are idempotent, the caller may call some of them
1334  * manually, then do some custom processing on the filtergraph, then call this
1335  * function to do the rest.
1336  *
1337  * @param seg the filtergraph segment to process
1338  * @param flags reserved for future use, caller must set to 0 for now
1339  * @param[out] inputs passed to avfilter_graph_segment_link()
1340  * @param[out] outputs passed to avfilter_graph_segment_link()
1341  *
1342  * @retval "non-negative number" success
1343  * @retval "negative error code" failure
1344  *
1345  * @note Calling this function multiple times is safe, as it is idempotent.
1346  */
1350 
1351 /**
1352  * Free the provided AVFilterGraphSegment and everything associated with it.
1353  *
1354  * @param seg double pointer to the AVFilterGraphSegment to be freed. NULL will
1355  * be written to this pointer on exit from this function.
1356  *
1357  * @note
1358  * The filter contexts (AVFilterParams.filter) are owned by AVFilterGraph rather
1359  * than AVFilterGraphSegment, so they are not freed.
1360  */
1362 
1363 /**
1364  * Send a command to one or more filter instances.
1365  *
1366  * @param graph the filter graph
1367  * @param target the filter(s) to which the command should be sent
1368  * "all" sends to all filters
1369  * otherwise it can be a filter or filter instance name
1370  * which will send the command to all matching filters.
1371  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1372  * @param arg the argument for the command
1373  * @param res a buffer with size res_size where the filter(s) can return a response.
1374  *
1375  * @returns >=0 on success otherwise an error code.
1376  * AVERROR(ENOSYS) on unsupported commands
1377  */
1378 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1379 
1380 /**
1381  * Queue a command for one or more filter instances.
1382  *
1383  * @param graph the filter graph
1384  * @param target the filter(s) to which the command should be sent
1385  * "all" sends to all filters
1386  * otherwise it can be a filter or filter instance name
1387  * which will send the command to all matching filters.
1388  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1389  * @param arg the argument for the command
1390  * @param ts time at which the command should be sent to the filter
1391  *
1392  * @note As this executes commands after this function returns, no return code
1393  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1394  */
1395 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1396 
1397 
1398 /**
1399  * Dump a graph into a human-readable string representation.
1400  *
1401  * @param graph the graph to dump
1402  * @param options formatting options; currently ignored
1403  * @return a string, or NULL in case of memory allocation failure;
1404  * the string must be freed using av_free
1405  */
1406 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1407 
1408 /**
1409  * Request a frame on the oldest sink link.
1410  *
1411  * If the request returns AVERROR_EOF, try the next.
1412  *
1413  * Note that this function is not meant to be the sole scheduling mechanism
1414  * of a filtergraph, only a convenience function to help drain a filtergraph
1415  * in a balanced way under normal circumstances.
1416  *
1417  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1418  * some of the sinks during the process.
1419  * When there are multiple sink links, in case the requested link
1420  * returns an EOF, this may cause a filter to flush pending frames
1421  * which are sent to another sink link, although unrequested.
1422  *
1423  * @return the return value of ff_request_frame(),
1424  * or AVERROR_EOF if all links returned AVERROR_EOF
1425  */
1427 
1428 /**
1429  * @}
1430  */
1431 
1432 #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:860
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:449
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
AVFilterFormatsConfig::samplerates
AVFilterFormats * samplerates
Lists of supported sample rates, only for audio.
Definition: avfilter.h:515
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:615
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:839
avfilter_pad_get_name
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
Definition: avfilter.c:972
AVFilterFormatsConfig::channel_layouts
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:520
AVFilterParams::instance_name
char * instance_name
Name to be used for this filter instance.
Definition: avfilter.h:1115
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:341
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:205
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:796
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:455
AVFilter::pix_fmt
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:356
rational.h
AVFilterContext::is_disabled
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:456
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:379
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:967
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:420
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:408
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:469
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:34
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:418
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
AVFilterParams::inputs
AVFilterPadParams ** inputs
Definition: avfilter.h:1129
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:116
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
AVFilterParams::outputs
AVFilterPadParams ** outputs
Definition: avfilter.h:1132
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:137
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:164
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:813
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:422
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:424
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:453
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:234
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:286
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
Definition: allfilters.c:618
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:492
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:846
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:365
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
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:414
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:1143
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:352
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:594
filters
#define filters(fmt, type, inverse, clp, inverset, clip, one, clip_fn, packed)
Definition: af_crystalizer.c:54
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:210
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:862
AVFilterFormatsConfig::color_spaces
AVFilterFormats * color_spaces
Lists of supported YUV color metadata, only for YUV video.
Definition: avfilter.h:525
AVFilterPadParams::label
char * label
An av_malloc()'ed string containing the pad label.
Definition: avfilter.h:1066
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:393
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:629
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:442
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:1319
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:881
AVFilterParams
Parameters describing a filter to be created in a filtergraph.
Definition: avfilter.h:1075
AVFilter::outputs
const AVFilterPad * outputs
List of static outputs.
Definition: avfilter.h:195
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:159
AVFilterParams::filter
AVFilterContext * filter
The filter context.
Definition: avfilter.h:1086
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterChain::nb_filters
size_t nb_filters
Definition: avfilter.h:1144
AVFilterParams::filter_name
char * filter_name
Name of the AVFilter to be used.
Definition: avfilter.h:1103
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:815
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:415
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:412
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:283
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
Definition: avfiltergraph.c:1449
AVFilterGraphSegment::chains
AVFilterChain ** chains
A list of filter chain contained in this segment.
Definition: avfilter.h:1167
AVFilterGraph
Definition: avfilter.h:813
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:1133
AVFilterFormatsConfig
Lists of formats / etc.
Definition: avfilter.h:505
AVFilterGraphSegment
A parsed representation of a filtergraph segment.
Definition: avfilter.h:1156
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:964
AVFilterGraph::scale_sws_opts
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:818
options
const OptionDef options[]
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:416
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:814
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:451
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:961
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:810
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:249
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:1367
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:1178
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:177
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
attributes.h
AVFilterFormatsConfig::color_ranges
AVFilterFormats * color_ranges
AVColorRange.
Definition: avfilter.h:526
AVFilter::nb_inputs
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:223
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:272
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
Definition: avfilter.c:944
AVFilterParams::nb_inputs
unsigned nb_inputs
Definition: avfilter.h:1130
AVFilter::query_func
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:326
log.h
AVFilterGraphSegment::graph
AVFilterGraph * graph
The filtergraph this segment is associated with.
Definition: avfilter.h:1161
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:919
AVFilterCommand
Definition: avfilter_internal.h:87
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:609
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:832
filt
static const int8_t filt[NUMTAPS *2]
Definition: af_earwax.c:39
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:363
AVFilter
Filter definition.
Definition: avfilter.h:166
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:35
AVFilterParams::opts
AVDictionary * opts
Options to be apllied to the filter.
Definition: avfilter.h:1127
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:155
dict.h
AVFilter::nb_outputs
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:228
avfilter_pad_get_type
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
Definition: avfilter.c:977
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
Definition: avfilter.c:903
AVFilterChain
A filterchain is a list of filter specifications.
Definition: avfilter.h:1142
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:454
AVFilterGraphSegment::nb_chains
size_t nb_chains
Definition: avfilter.h:1168
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
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
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:929
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:510
AVFilter::inputs
const AVFilterPad * inputs
List of static inputs.
Definition: avfilter.h:186
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:284
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:780
AVFilter::sample_fmt
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:360
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:958
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:928
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:1337
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:816
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:410
AVFilter::formats
union AVFilter::@243 formats
The state of the following union is determined by formats_state.
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:648
int
int
Definition: ffmpeg_filter.c:425
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:1611
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:956
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:476
AVFilterPadParams
Parameters of a filter's input or output pad.
Definition: avfilter.h:1058
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:419