FFmpeg  4.2.2
avfilter.h
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1 /*
2  * filter layer
3  * Copyright (c) 2007 Bobby Bingham
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVFILTER_AVFILTER_H
23 #define AVFILTER_AVFILTER_H
24 
25 /**
26  * @file
27  * @ingroup lavfi
28  * Main libavfilter public API header
29  */
30 
31 /**
32  * @defgroup lavfi libavfilter
33  * Graph-based frame editing library.
34  *
35  * @{
36  */
37 
38 #include <stddef.h>
39 
40 #include "libavutil/attributes.h"
41 #include "libavutil/avutil.h"
42 #include "libavutil/buffer.h"
43 #include "libavutil/dict.h"
44 #include "libavutil/frame.h"
45 #include "libavutil/log.h"
46 #include "libavutil/samplefmt.h"
47 #include "libavutil/pixfmt.h"
48 #include "libavutil/rational.h"
49 
50 #include "libavfilter/version.h"
51 
52 /**
53  * Return the LIBAVFILTER_VERSION_INT constant.
54  */
55 unsigned avfilter_version(void);
56 
57 /**
58  * Return the libavfilter build-time configuration.
59  */
60 const char *avfilter_configuration(void);
61 
62 /**
63  * Return the libavfilter license.
64  */
65 const char *avfilter_license(void);
66 
67 typedef struct AVFilterContext AVFilterContext;
68 typedef struct AVFilterLink AVFilterLink;
69 typedef struct AVFilterPad AVFilterPad;
71 
72 /**
73  * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
74  * AVFilter.inputs/outputs).
75  */
76 int avfilter_pad_count(const AVFilterPad *pads);
77 
78 /**
79  * Get the name of an AVFilterPad.
80  *
81  * @param pads an array of AVFilterPads
82  * @param pad_idx index of the pad in the array it; is the caller's
83  * responsibility to ensure the index is valid
84  *
85  * @return name of the pad_idx'th pad in pads
86  */
87 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
88 
89 /**
90  * Get the type 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 type of the pad_idx'th pad in pads
97  */
98 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
99 
100 /**
101  * The number of the filter inputs is not determined just by AVFilter.inputs.
102  * The filter might add additional inputs during initialization depending on the
103  * options supplied to it.
104  */
105 #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
106 /**
107  * The number of the filter outputs is not determined just by AVFilter.outputs.
108  * The filter might add additional outputs during initialization depending on
109  * the options supplied to it.
110  */
111 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
112 /**
113  * The filter supports multithreading by splitting frames into multiple parts
114  * and processing them concurrently.
115  */
116 #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
117 /**
118  * Some filters support a generic "enable" expression option that can be used
119  * to enable or disable a filter in the timeline. Filters supporting this
120  * option have this flag set. When the enable expression is false, the default
121  * no-op filter_frame() function is called in place of the filter_frame()
122  * callback defined on each input pad, thus the frame is passed unchanged to
123  * the next filters.
124  */
125 #define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16)
126 /**
127  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
128  * have its filter_frame() callback(s) called as usual even when the enable
129  * expression is false. The filter will disable filtering within the
130  * filter_frame() callback(s) itself, for example executing code depending on
131  * the AVFilterContext->is_disabled value.
132  */
133 #define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17)
134 /**
135  * Handy mask to test whether the filter supports or no the timeline feature
136  * (internally or generically).
137  */
138 #define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL)
139 
140 /**
141  * Filter definition. This defines the pads a filter contains, and all the
142  * callback functions used to interact with the filter.
143  */
144 typedef struct AVFilter {
145  /**
146  * Filter name. Must be non-NULL and unique among filters.
147  */
148  const char *name;
149 
150  /**
151  * A description of the filter. May be NULL.
152  *
153  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
154  */
155  const char *description;
156 
157  /**
158  * List of inputs, terminated by a zeroed element.
159  *
160  * NULL if there are no (static) inputs. Instances of filters with
161  * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
162  * this list.
163  */
165  /**
166  * List of outputs, terminated by a zeroed element.
167  *
168  * NULL if there are no (static) outputs. Instances of filters with
169  * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
170  * this list.
171  */
173 
174  /**
175  * A class for the private data, used to declare filter private AVOptions.
176  * This field is NULL for filters that do not declare any options.
177  *
178  * If this field is non-NULL, the first member of the filter private data
179  * must be a pointer to AVClass, which will be set by libavfilter generic
180  * code to this class.
181  */
183 
184  /**
185  * A combination of AVFILTER_FLAG_*
186  */
187  int flags;
188  /**
189  * The number of entries in the list of inputs.
190  */
191  uint8_t nb_inputs;
192 
193  /**
194  * The number of entries in the list of outputs.
195  */
196  uint8_t nb_outputs;
197 
198  /**
199  * This field determines the state of the formats union.
200  * It is an enum FilterFormatsState value.
201  */
202  uint8_t formats_state;
203  /*****************************************************************
204  * All fields below this line are not part of the public API. They
205  * may not be used outside of libavfilter and can be changed and
206  * removed at will.
207  * New public fields should be added right above.
208  *****************************************************************
209  */
210 
211  /**
212  * Filter pre-initialization function
213  *
214  * This callback will be called immediately after the filter context is
215  * allocated, to allow allocating and initing sub-objects.
216  *
217  * If this callback is not NULL, the uninit callback will be called on
218  * allocation failure.
219  *
220  * @return 0 on success,
221  * AVERROR code on failure (but the code will be
222  * dropped and treated as ENOMEM by the calling code)
223  */
224  int (*preinit)(AVFilterContext *ctx);
225 
226  /**
227  * Filter initialization function.
228  *
229  * This callback will be called only once during the filter lifetime, after
230  * all the options have been set, but before links between filters are
231  * established and format negotiation is done.
232  *
233  * Basic filter initialization should be done here. Filters with dynamic
234  * inputs and/or outputs should create those inputs/outputs here based on
235  * provided options. No more changes to this filter's inputs/outputs can be
236  * done after this callback.
237  *
238  * This callback must not assume that the filter links exist or frame
239  * parameters are known.
240  *
241  * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
242  * initialization fails, so this callback does not have to clean up on
243  * failure.
244  *
245  * @return 0 on success, a negative AVERROR on failure
246  */
247  int (*init)(AVFilterContext *ctx);
248 
249  /**
250  * Should be set instead of @ref AVFilter.init "init" by the filters that
251  * want to pass a dictionary of AVOptions to nested contexts that are
252  * allocated during init.
253  *
254  * On return, the options dict should be freed and replaced with one that
255  * contains all the options which could not be processed by this filter (or
256  * with NULL if all the options were processed).
257  *
258  * Otherwise the semantics is the same as for @ref AVFilter.init "init".
259  */
260  int (*init_dict)(AVFilterContext *ctx, AVDictionary **options);
261 
262  /**
263  * Filter uninitialization function.
264  *
265  * Called only once right before the filter is freed. Should deallocate any
266  * memory held by the filter, release any buffer references, etc. It does
267  * not need to deallocate the AVFilterContext.priv memory itself.
268  *
269  * This callback may be called even if @ref AVFilter.init "init" was not
270  * called or failed, so it must be prepared to handle such a situation.
271  */
272  void (*uninit)(AVFilterContext *ctx);
273 
274  /**
275  * Query formats supported by the filter on its inputs and outputs.
276  *
277  * This callback is called after the filter is initialized (so the inputs
278  * and outputs are fixed), shortly before the format negotiation. This
279  * callback may be called more than once.
280  *
281  * This callback must set AVFilterLink.out_formats on every input link and
282  * AVFilterLink.in_formats on every output link to a list of pixel/sample
283  * formats that the filter supports on that link. For audio links, this
284  * filter must also set @ref AVFilterLink.in_samplerates "in_samplerates" /
285  * @ref AVFilterLink.out_samplerates "out_samplerates" and
286  * @ref AVFilterLink.in_channel_layouts "in_channel_layouts" /
287  * @ref AVFilterLink.out_channel_layouts "out_channel_layouts" analogously.
288  *
289  * This callback may be NULL for filters with one input, in which case
290  * libavfilter assumes that it supports all input formats and preserves
291  * them on output.
292  *
293  * @return zero on success, a negative value corresponding to an
294  * AVERROR code otherwise
295  */
297 
298  union {
299  /**
300  * Query formats supported by the filter on its inputs and outputs.
301  *
302  * This callback is called after the filter is initialized (so the inputs
303  * and outputs are fixed), shortly before the format negotiation. This
304  * callback may be called more than once.
305  *
306  * This callback must set ::AVFilterLink's
307  * @ref AVFilterFormatsConfig.formats "outcfg.formats"
308  * on every input link and
309  * @ref AVFilterFormatsConfig.formats "incfg.formats"
310  * on every output link to a list of pixel/sample formats that the filter
311  * supports on that link.
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  * This list must never be NULL if the union is in this state.
334  * The type of all inputs and outputs of filters using this must
335  * be AVMEDIA_TYPE_VIDEO.
336  */
338  /**
339  * Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
340  * and restricted to filters that only have AVMEDIA_TYPE_AUDIO
341  * inputs and outputs.
342  *
343  * In addition to that the generic code will mark all inputs
344  * and all outputs as supporting all sample rates and every
345  * channel count and channel layout, as long as all inputs
346  * and outputs use the same sample rate and channel count/layout.
347  */
349  /**
350  * Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
351  */
353  /**
354  * Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
355  */
357  } formats;
358 
359  int priv_size; ///< size of private data to allocate for the filter
360 
361  int flags_internal; ///< Additional flags for avfilter internal use only.
362 
363  /**
364  * Used by the filter registration system. Must not be touched by any other
365  * code.
366  */
367  struct AVFilter *next;
368 
369  /**
370  * Make the filter instance process a command.
371  *
372  * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
373  * @param arg the argument for the command
374  * @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.
375  * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
376  * time consuming then a filter should treat it like an unsupported command
377  *
378  * @returns >=0 on success otherwise an error code.
379  * AVERROR(ENOSYS) on unsupported commands
380  */
381  int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
382 
383  /**
384  * Filter initialization function, alternative to the init()
385  * callback. Args contains the user-supplied parameters, opaque is
386  * used for providing binary data.
387  */
388  int (*init_opaque)(AVFilterContext *ctx, void *opaque);
389 
390  /**
391  * Filter activation function.
392  *
393  * Called when any processing is needed from the filter, instead of any
394  * filter_frame and request_frame on pads.
395  *
396  * The function must examine inlinks and outlinks and perform a single
397  * step of processing. If there is nothing to do, the function must do
398  * nothing and not return an error. If more steps are or may be
399  * possible, it must use ff_filter_set_ready() to schedule another
400  * activation.
401  */
402  int (*activate)(AVFilterContext *ctx);
403 } AVFilter;
404 
405 /**
406  * Process multiple parts of the frame concurrently.
407  */
408 #define AVFILTER_THREAD_SLICE (1 << 0)
409 
411 
412 /** An instance of a filter */
414  const AVClass *av_class; ///< needed for av_log() and filters common options
415 
416  const AVFilter *filter; ///< the AVFilter of which this is an instance
417 
418  char *name; ///< name of this filter instance
419 
420  AVFilterPad *input_pads; ///< array of input pads
421  AVFilterLink **inputs; ///< array of pointers to input links
422  unsigned nb_inputs; ///< number of input pads
423 
424  AVFilterPad *output_pads; ///< array of output pads
425  AVFilterLink **outputs; ///< array of pointers to output links
426  unsigned nb_outputs; ///< number of output pads
427 
428  void *priv; ///< private data for use by the filter
429 
430  struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
431 
432  /**
433  * Type of multithreading being allowed/used. A combination of
434  * AVFILTER_THREAD_* flags.
435  *
436  * May be set by the caller before initializing the filter to forbid some
437  * or all kinds of multithreading for this filter. The default is allowing
438  * everything.
439  *
440  * When the filter is initialized, this field is combined using bit AND with
441  * AVFilterGraph.thread_type to get the final mask used for determining
442  * allowed threading types. I.e. a threading type needs to be set in both
443  * to be allowed.
444  *
445  * After the filter is initialized, libavfilter sets this field to the
446  * threading type that is actually used (0 for no multithreading).
447  */
449 
450  /**
451  * An opaque struct for libavfilter internal use.
452  */
453  AVFilterInternal *internal;
454 
455  struct AVFilterCommand *command_queue;
456 
457  char *enable_str; ///< enable expression string
458  void *enable; ///< parsed expression (AVExpr*)
459  double *var_values; ///< variable values for the enable expression
460  int is_disabled; ///< the enabled state from the last expression evaluation
461 
462  /**
463  * For filters which will create hardware frames, sets the device the
464  * filter should create them in. All other filters will ignore this field:
465  * in particular, a filter which consumes or processes hardware frames will
466  * instead use the hw_frames_ctx field in AVFilterLink to carry the
467  * hardware context information.
468  */
470 
471  /**
472  * Max number of threads allowed in this filter instance.
473  * If <= 0, its value is ignored.
474  * Overrides global number of threads set per filter graph.
475  */
477 
478  /**
479  * Ready status of the filter.
480  * A non-0 value means that the filter needs activating;
481  * a higher value suggests a more urgent activation.
482  */
483  unsigned ready;
484 
485  /**
486  * Sets the number of extra hardware frames which the filter will
487  * allocate on its output links for use in following filters or by
488  * the caller.
489  *
490  * Some hardware filters require all frames that they will use for
491  * output to be defined in advance before filtering starts. For such
492  * filters, any hardware frame pools used for output must therefore be
493  * of fixed size. The extra frames set here are on top of any number
494  * that the filter needs internally in order to operate normally.
495  *
496  * This field must be set before the graph containing this filter is
497  * configured.
498  */
500 };
501 
502 /**
503  * A link between two filters. This contains pointers to the source and
504  * destination filters between which this link exists, and the indexes of
505  * the pads involved. In addition, this link also contains the parameters
506  * which have been negotiated and agreed upon between the filter, such as
507  * image dimensions, format, etc.
508  *
509  * Applications must not normally access the link structure directly.
510  * Use the buffersrc and buffersink API instead.
511  * In the future, access to the header may be reserved for filters
512  * implementation.
513  */
514 struct AVFilterLink {
515  AVFilterContext *src; ///< source filter
516  AVFilterPad *srcpad; ///< output pad on the source filter
517 
518  AVFilterContext *dst; ///< dest filter
519  AVFilterPad *dstpad; ///< input pad on the dest filter
520 
521  enum AVMediaType type; ///< filter media type
522 
523  /* These parameters apply only to video */
524  int w; ///< agreed upon image width
525  int h; ///< agreed upon image height
526  AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
527  /* These parameters apply only to audio */
528  uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
529  int sample_rate; ///< samples per second
530 
531  int format; ///< agreed upon media format
532 
533  /**
534  * Define the time base used by the PTS of the frames/samples
535  * which will pass through this link.
536  * During the configuration stage, each filter is supposed to
537  * change only the output timebase, while the timebase of the
538  * input link is assumed to be an unchangeable property.
539  */
541 
542  /*****************************************************************
543  * All fields below this line are not part of the public API. They
544  * may not be used outside of libavfilter and can be changed and
545  * removed at will.
546  * New public fields should be added right above.
547  *****************************************************************
548  */
549  /**
550  * Lists of formats and channel layouts supported by the input and output
551  * filters respectively. These lists are used for negotiating the format
552  * to actually be used, which will be loaded into the format and
553  * channel_layout members, above, when chosen.
554  *
555  */
558 
559  /**
560  * Lists of channel layouts and sample rates used for automatic
561  * negotiation.
562  */
565  struct AVFilterChannelLayouts *in_channel_layouts;
566  struct AVFilterChannelLayouts *out_channel_layouts;
567 
568  /**
569  * Audio only, the destination filter sets this to a non-zero value to
570  * request that buffers with the given number of samples should be sent to
571  * it. AVFilterPad.needs_fifo must also be set on the corresponding input
572  * pad.
573  * Last buffer before EOF will be padded with silence.
574  */
576 
577  /** stage of the initialization of the link properties (dimensions, etc) */
578  enum {
579  AVLINK_UNINIT = 0, ///< not started
580  AVLINK_STARTINIT, ///< started, but incomplete
581  AVLINK_INIT ///< complete
582  } init_state;
583 
584  /**
585  * Graph the filter belongs to.
586  */
588 
589  /**
590  * Current timestamp of the link, as defined by the most recent
591  * frame(s), in link time_base units.
592  */
593  int64_t current_pts;
594 
595  /**
596  * Current timestamp of the link, as defined by the most recent
597  * frame(s), in AV_TIME_BASE units.
598  */
599  int64_t current_pts_us;
600 
601  /**
602  * Index in the age array.
603  */
605 
606  /**
607  * Frame rate of the stream on the link, or 1/0 if unknown or variable;
608  * if left to 0/0, will be automatically copied from the first input
609  * of the source filter if it exists.
610  *
611  * Sources should set it to the best estimation of the real frame rate.
612  * If the source frame rate is unknown or variable, set this to 1/0.
613  * Filters should update it if necessary depending on their function.
614  * Sinks can use it to set a default output frame rate.
615  * It is similar to the r_frame_rate field in AVStream.
616  */
618 
619  /**
620  * Buffer partially filled with samples to achieve a fixed/minimum size.
621  */
623 
624  /**
625  * Size of the partial buffer to allocate.
626  * Must be between min_samples and max_samples.
627  */
629 
630  /**
631  * Minimum number of samples to filter at once. If filter_frame() is
632  * called with fewer samples, it will accumulate them in partial_buf.
633  * This field and the related ones must not be changed after filtering
634  * has started.
635  * If 0, all related fields are ignored.
636  */
638 
639  /**
640  * Maximum number of samples to filter at once. If filter_frame() is
641  * called with more samples, it will split them.
642  */
644 
645  /**
646  * Number of channels.
647  */
648  int channels;
649 
650  /**
651  * Link processing flags.
652  */
653  unsigned flags;
654 
655  /**
656  * Number of past frames sent through the link.
657  */
659 
660  /**
661  * A pointer to a FFFramePool struct.
662  */
663  void *frame_pool;
664 
665  /**
666  * True if a frame is currently wanted on the output of this filter.
667  * Set when ff_request_frame() is called by the output,
668  * cleared when a frame is filtered.
669  */
671 
672  /**
673  * For hwaccel pixel formats, this should be a reference to the
674  * AVHWFramesContext describing the frames.
675  */
677 
678 #ifndef FF_INTERNAL_FIELDS
679 
680  /**
681  * Internal structure members.
682  * The fields below this limit are internal for libavfilter's use
683  * and must in no way be accessed by applications.
684  */
685  char reserved[0xF000];
686 
687 #else /* FF_INTERNAL_FIELDS */
688 
689  /**
690  * Queue of frames waiting to be filtered.
691  */
692  FFFrameQueue fifo;
693 
694  /**
695  * If set, the source filter can not generate a frame as is.
696  * The goal is to avoid repeatedly calling the request_frame() method on
697  * the same link.
698  */
699  int frame_blocked_in;
700 
701  /**
702  * Link input status.
703  * If not zero, all attempts of filter_frame will fail with the
704  * corresponding code.
705  */
706  int status_in;
707 
708  /**
709  * Timestamp of the input status change.
710  */
711  int64_t status_in_pts;
712 
713  /**
714  * Link output status.
715  * If not zero, all attempts of request_frame will fail with the
716  * corresponding code.
717  */
718  int status_out;
719 
720 #endif /* FF_INTERNAL_FIELDS */
721 
722 };
723 
724 /**
725  * Link two filters together.
726  *
727  * @param src the source filter
728  * @param srcpad index of the output pad on the source filter
729  * @param dst the destination filter
730  * @param dstpad index of the input pad on the destination filter
731  * @return zero on success
732  */
733 int avfilter_link(AVFilterContext *src, unsigned srcpad,
734  AVFilterContext *dst, unsigned dstpad);
735 
736 /**
737  * Free the link in *link, and set its pointer to NULL.
738  */
739 void avfilter_link_free(AVFilterLink **link);
740 
741 #if FF_API_FILTER_GET_SET
742 /**
743  * Get the number of channels of a link.
744  * @deprecated Use av_buffersink_get_channels()
745  */
748 #endif
749 
750 /**
751  * Set the closed field of a link.
752  * @deprecated applications are not supposed to mess with links, they should
753  * close the sinks.
754  */
756 void avfilter_link_set_closed(AVFilterLink *link, int closed);
757 
758 /**
759  * Negotiate the media format, dimensions, etc of all inputs to a filter.
760  *
761  * @param filter the filter to negotiate the properties for its inputs
762  * @return zero on successful negotiation
763  */
765 
766 #define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
767 #define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
768 
769 /**
770  * Make the filter instance process a command.
771  * It is recommended to use avfilter_graph_send_command().
772  */
773 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
774 
775 /**
776  * Iterate over all registered filters.
777  *
778  * @param opaque a pointer where libavfilter will store the iteration state. Must
779  * point to NULL to start the iteration.
780  *
781  * @return the next registered filter or NULL when the iteration is
782  * finished
783  */
784 const AVFilter *av_filter_iterate(void **opaque);
785 
786 #if FF_API_NEXT
787 /** Initialize the filter system. Register all builtin filters. */
789 void avfilter_register_all(void);
790 
791 /**
792  * Register a filter. This is only needed if you plan to use
793  * avfilter_get_by_name later to lookup the AVFilter structure by name. A
794  * filter can still by instantiated with avfilter_graph_alloc_filter even if it
795  * is not registered.
796  *
797  * @param filter the filter to register
798  * @return 0 if the registration was successful, a negative value
799  * otherwise
800  */
802 int avfilter_register(AVFilter *filter);
803 
804 /**
805  * Iterate over all registered filters.
806  * @return If prev is non-NULL, next registered filter after prev or NULL if
807  * prev is the last filter. If prev is NULL, return the first registered filter.
808  */
810 const AVFilter *avfilter_next(const AVFilter *prev);
811 #endif
812 
813 /**
814  * Get a filter definition matching the given name.
815  *
816  * @param name the filter name to find
817  * @return the filter definition, if any matching one is registered.
818  * NULL if none found.
819  */
820 const AVFilter *avfilter_get_by_name(const char *name);
821 
822 
823 /**
824  * Initialize a filter with the supplied parameters.
825  *
826  * @param ctx uninitialized filter context to initialize
827  * @param args Options to initialize the filter with. This must be a
828  * ':'-separated list of options in the 'key=value' form.
829  * May be NULL if the options have been set directly using the
830  * AVOptions API or there are no options that need to be set.
831  * @return 0 on success, a negative AVERROR on failure
832  */
833 int avfilter_init_str(AVFilterContext *ctx, const char *args);
834 
835 /**
836  * Initialize a filter with the supplied dictionary of options.
837  *
838  * @param ctx uninitialized filter context to initialize
839  * @param options An AVDictionary filled with options for this filter. On
840  * return this parameter will be destroyed and replaced with
841  * a dict containing options that were not found. This dictionary
842  * must be freed by the caller.
843  * May be NULL, then this function is equivalent to
844  * avfilter_init_str() with the second parameter set to NULL.
845  * @return 0 on success, a negative AVERROR on failure
846  *
847  * @note This function and avfilter_init_str() do essentially the same thing,
848  * the difference is in manner in which the options are passed. It is up to the
849  * calling code to choose whichever is more preferable. The two functions also
850  * behave differently when some of the provided options are not declared as
851  * supported by the filter. In such a case, avfilter_init_str() will fail, but
852  * this function will leave those extra options in the options AVDictionary and
853  * continue as usual.
854  */
855 int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options);
856 
857 /**
858  * Free a filter context. This will also remove the filter from its
859  * filtergraph's list of filters.
860  *
861  * @param filter the filter to free
862  */
863 void avfilter_free(AVFilterContext *filter);
864 
865 /**
866  * Insert a filter in the middle of an existing link.
867  *
868  * @param link the link into which the filter should be inserted
869  * @param filt the filter to be inserted
870  * @param filt_srcpad_idx the input pad on the filter to connect
871  * @param filt_dstpad_idx the output pad on the filter to connect
872  * @return zero on success
873  */
875  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
876 
877 /**
878  * @return AVClass for AVFilterContext.
879  *
880  * @see av_opt_find().
881  */
882 const AVClass *avfilter_get_class(void);
883 
885 
886 /**
887  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
888  * executed multiple times, possibly in parallel.
889  *
890  * @param ctx the filter context the job belongs to
891  * @param arg an opaque parameter passed through from @ref
892  * AVFilterGraph.execute
893  * @param jobnr the index of the job being executed
894  * @param nb_jobs the total number of jobs
895  *
896  * @return 0 on success, a negative AVERROR on error
897  */
898 typedef int (avfilter_action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
899 
900 /**
901  * A function executing multiple jobs, possibly in parallel.
902  *
903  * @param ctx the filter context to which the jobs belong
904  * @param func the function to be called multiple times
905  * @param arg the argument to be passed to func
906  * @param ret a nb_jobs-sized array to be filled with return values from each
907  * invocation of func
908  * @param nb_jobs the number of jobs to execute
909  *
910  * @return 0 on success, a negative AVERROR on error
911  */
913  void *arg, int *ret, int nb_jobs);
914 
915 typedef struct AVFilterGraph {
918  unsigned nb_filters;
919 
920  char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
921 #if FF_API_LAVR_OPTS
922  attribute_deprecated char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters
923 #endif
924 
925  /**
926  * Type of multithreading allowed for filters in this graph. A combination
927  * of AVFILTER_THREAD_* flags.
928  *
929  * May be set by the caller at any point, the setting will apply to all
930  * filters initialized after that. The default is allowing everything.
931  *
932  * When a filter in this graph is initialized, this field is combined using
933  * bit AND with AVFilterContext.thread_type to get the final mask used for
934  * determining allowed threading types. I.e. a threading type needs to be
935  * set in both to be allowed.
936  */
938 
939  /**
940  * Maximum number of threads used by filters in this graph. May be set by
941  * the caller before adding any filters to the filtergraph. Zero (the
942  * default) means that the number of threads is determined automatically.
943  */
945 
946  /**
947  * Opaque object for libavfilter internal use.
948  */
950 
951  /**
952  * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
953  * be used from callbacks like @ref AVFilterGraph.execute.
954  * Libavfilter will not touch this field in any way.
955  */
956  void *opaque;
957 
958  /**
959  * This callback may be set by the caller immediately after allocating the
960  * graph and before adding any filters to it, to provide a custom
961  * multithreading implementation.
962  *
963  * If set, filters with slice threading capability will call this callback
964  * to execute multiple jobs in parallel.
965  *
966  * If this field is left unset, libavfilter will use its internal
967  * implementation, which may or may not be multithreaded depending on the
968  * platform and build options.
969  */
971 
972  char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
973 
974  /**
975  * Private fields
976  *
977  * The following fields are for internal use only.
978  * Their type, offset, number and semantic can change without notice.
979  */
980 
983 
985 } AVFilterGraph;
986 
987 /**
988  * Allocate a filter graph.
989  *
990  * @return the allocated filter graph on success or NULL.
991  */
993 
994 /**
995  * Create a new filter instance in a filter graph.
996  *
997  * @param graph graph in which the new filter will be used
998  * @param filter the filter to create an instance of
999  * @param name Name to give to the new instance (will be copied to
1000  * AVFilterContext.name). This may be used by the caller to identify
1001  * different filters, libavfilter itself assigns no semantics to
1002  * this parameter. May be NULL.
1003  *
1004  * @return the context of the newly created filter instance (note that it is
1005  * also retrievable directly through AVFilterGraph.filters or with
1006  * avfilter_graph_get_filter()) on success or NULL on failure.
1007  */
1009  const AVFilter *filter,
1010  const char *name);
1011 
1012 /**
1013  * Get a filter instance identified by instance name from graph.
1014  *
1015  * @param graph filter graph to search through.
1016  * @param name filter instance name (should be unique in the graph).
1017  * @return the pointer to the found filter instance or NULL if it
1018  * cannot be found.
1019  */
1020 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, const char *name);
1021 
1022 /**
1023  * Create and add a filter instance into an existing graph.
1024  * The filter instance is created from the filter filt and inited
1025  * with the parameters args and opaque.
1026  *
1027  * In case of success put in *filt_ctx the pointer to the created
1028  * filter instance, otherwise set *filt_ctx to NULL.
1029  *
1030  * @param name the instance name to give to the created filter instance
1031  * @param graph_ctx the filter graph
1032  * @return a negative AVERROR error code in case of failure, a non
1033  * negative value otherwise
1034  */
1035 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt,
1036  const char *name, const char *args, void *opaque,
1037  AVFilterGraph *graph_ctx);
1038 
1039 /**
1040  * Enable or disable automatic format conversion inside the graph.
1041  *
1042  * Note that format conversion can still happen inside explicitly inserted
1043  * scale and aresample filters.
1044  *
1045  * @param flags any of the AVFILTER_AUTO_CONVERT_* constants
1046  */
1047 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags);
1048 
1049 enum {
1050  AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */
1051  AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
1052 };
1053 
1054 /**
1055  * Check validity and configure all the links and formats in the graph.
1056  *
1057  * @param graphctx the filter graph
1058  * @param log_ctx context used for logging
1059  * @return >= 0 in case of success, a negative AVERROR code otherwise
1060  */
1061 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1062 
1063 /**
1064  * Free a graph, destroy its links, and set *graph to NULL.
1065  * If *graph is NULL, do nothing.
1066  */
1067 void avfilter_graph_free(AVFilterGraph **graph);
1068 
1069 /**
1070  * A linked-list of the inputs/outputs of the filter chain.
1071  *
1072  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1073  * where it is used to communicate open (unlinked) inputs and outputs from and
1074  * to the caller.
1075  * This struct specifies, per each not connected pad contained in the graph, the
1076  * filter context and the pad index required for establishing a link.
1077  */
1078 typedef struct AVFilterInOut {
1079  /** unique name for this input/output in the list */
1080  char *name;
1081 
1082  /** filter context associated to this input/output */
1084 
1085  /** index of the filt_ctx pad to use for linking */
1086  int pad_idx;
1087 
1088  /** next input/input in the list, NULL if this is the last */
1090 } AVFilterInOut;
1091 
1092 /**
1093  * Allocate a single AVFilterInOut entry.
1094  * Must be freed with avfilter_inout_free().
1095  * @return allocated AVFilterInOut on success, NULL on failure.
1096  */
1098 
1099 /**
1100  * Free the supplied list of AVFilterInOut and set *inout to NULL.
1101  * If *inout is NULL, do nothing.
1102  */
1103 void avfilter_inout_free(AVFilterInOut **inout);
1104 
1105 /**
1106  * Add a graph described by a string to a graph.
1107  *
1108  * @note The caller must provide the lists of inputs and outputs,
1109  * which therefore must be known before calling the function.
1110  *
1111  * @note The inputs parameter describes inputs of the already existing
1112  * part of the graph; i.e. from the point of view of the newly created
1113  * part, they are outputs. Similarly the outputs parameter describes
1114  * outputs of the already existing filters, which are provided as
1115  * inputs to the parsed filters.
1116  *
1117  * @param graph the filter graph where to link the parsed graph context
1118  * @param filters string to be parsed
1119  * @param inputs linked list to the inputs of the graph
1120  * @param outputs linked list to the outputs of the graph
1121  * @return zero on success, a negative AVERROR code on error
1122  */
1123 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1124  AVFilterInOut *inputs, AVFilterInOut *outputs,
1125  void *log_ctx);
1126 
1127 /**
1128  * Add a graph described by a string to a graph.
1129  *
1130  * In the graph filters description, if the input label of the first
1131  * filter is not specified, "in" is assumed; if the output label of
1132  * the last filter is not specified, "out" is assumed.
1133  *
1134  * @param graph the filter graph where to link the parsed graph context
1135  * @param filters string to be parsed
1136  * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
1137  * If non-NULL, *inputs is updated to contain the list of open inputs
1138  * after the parsing, should be freed with avfilter_inout_free().
1139  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1140  * If non-NULL, *outputs is updated to contain the list of open outputs
1141  * after the parsing, should be freed with avfilter_inout_free().
1142  * @return non negative on success, a negative AVERROR code on error
1143  */
1144 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1145  AVFilterInOut **inputs, AVFilterInOut **outputs,
1146  void *log_ctx);
1147 
1148 /**
1149  * Add a graph described by a string to a graph.
1150  *
1151  * @param[in] graph the filter graph where to link the parsed graph context
1152  * @param[in] filters string to be parsed
1153  * @param[out] inputs a linked list of all free (unlinked) inputs of the
1154  * parsed graph will be returned here. It is to be freed
1155  * by the caller using avfilter_inout_free().
1156  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1157  * parsed graph will be returned here. It is to be freed by the
1158  * caller using avfilter_inout_free().
1159  * @return zero on success, a negative AVERROR code on error
1160  *
1161  * @note This function returns the inputs and outputs that are left
1162  * unlinked after parsing the graph and the caller then deals with
1163  * them.
1164  * @note This function makes no reference whatsoever to already
1165  * existing parts of the graph and the inputs parameter will on return
1166  * contain inputs of the newly parsed part of the graph. Analogously
1167  * the outputs parameter will contain outputs of the newly created
1168  * filters.
1169  */
1170 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1171  AVFilterInOut **inputs,
1172  AVFilterInOut **outputs);
1173 
1174 /**
1175  * Send a command to one or more filter instances.
1176  *
1177  * @param graph the filter graph
1178  * @param target the filter(s) to which the command should be sent
1179  * "all" sends to all filters
1180  * otherwise it can be a filter or filter instance name
1181  * which will send the command to all matching filters.
1182  * @param cmd the command to send, for handling simplicity all commands must be alphanumeric only
1183  * @param arg the argument for the command
1184  * @param res a buffer with size res_size where the filter(s) can return a response.
1185  *
1186  * @returns >=0 on success otherwise an error code.
1187  * AVERROR(ENOSYS) on unsupported commands
1188  */
1189 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1190 
1191 /**
1192  * Queue a command for one or more filter instances.
1193  *
1194  * @param graph the filter graph
1195  * @param target the filter(s) to which the command should be sent
1196  * "all" sends to all filters
1197  * otherwise it can be a filter or filter instance name
1198  * which will send the command to all matching filters.
1199  * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
1200  * @param arg the argument for the command
1201  * @param ts time at which the command should be sent to the filter
1202  *
1203  * @note As this executes commands after this function returns, no return code
1204  * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1205  */
1206 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1207 
1208 
1209 /**
1210  * Dump a graph into a human-readable string representation.
1211  *
1212  * @param graph the graph to dump
1213  * @param options formatting options; currently ignored
1214  * @return a string, or NULL in case of memory allocation failure;
1215  * the string must be freed using av_free
1216  */
1217 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1218 
1219 /**
1220  * Request a frame on the oldest sink link.
1221  *
1222  * If the request returns AVERROR_EOF, try the next.
1223  *
1224  * Note that this function is not meant to be the sole scheduling mechanism
1225  * of a filtergraph, only a convenience function to help drain a filtergraph
1226  * in a balanced way under normal circumstances.
1227  *
1228  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1229  * some of the sinks during the process.
1230  * When there are multiple sink links, in case the requested link
1231  * returns an EOF, this may cause a filter to flush pending frames
1232  * which are sent to another sink link, although unrequested.
1233  *
1234  * @return the return value of ff_request_frame(),
1235  * or AVERROR_EOF if all links returned AVERROR_EOF
1236  */
1238 
1239 /**
1240  * @}
1241  */
1242 
1243 #endif /* AVFILTER_AVFILTER_H */
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:970
AVFilterContext::nb_threads
int nb_threads
Max number of threads allowed in this filter instance.
Definition: avfilter.h:476
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
avfilter_register_all
attribute_deprecated void avfilter_register_all(void)
Initialize the filter system.
AVFilterGraph::nb_threads
int nb_threads
Maximum number of threads used by filters in this graph.
Definition: avfilter.h:944
avfilter_pad_get_name
const char * avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)
Get the name of an AVFilterPad.
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:337
AVFilter::priv_class
const AVClass * priv_class
A class for the private data, used to declare filter private AVOptions.
Definition: avfilter.h:182
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:898
AVFilterContext::var_values
double * var_values
variable values for the enable expression
Definition: avfilter.h:459
AVFilter::pix_fmt
enum AVPixelFormat pix_fmt
Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
Definition: avfilter.h:352
rational.h
AVFilterContext::is_disabled
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:460
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:381
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVFilterInOut::next
struct AVFilterInOut * next
next input/input in the list, NULL if this is the last
Definition: avfilter.h:1089
AVFilterContext::nb_outputs
unsigned nb_outputs
number of output pads
Definition: avfilter.h:426
AVFilterContext::av_class
const AVClass * av_class
needed for av_log() and filters common options
Definition: avfilter.h:414
AVFilterGraph::disable_auto_convert
unsigned disable_auto_convert
Definition: avfilter.h:984
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
AVFilterContext::output_pads
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:424
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:148
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
AVFilterFormats
struct AVFilterFormats AVFilterFormats
Definition: avfilter.h:70
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.
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.
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:428
AVFilterContext::graph
struct AVFilterGraph * graph
filtergraph this filter belongs to
Definition: avfilter.h:430
AVFilterContext::enable_str
char * enable_str
enable expression string
Definition: avfilter.h:457
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
AVFilter::formats_state
uint8_t formats_state
This field determines the state of the formats union.
Definition: avfilter.h:202
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.
av_filter_iterate
const AVFilter * av_filter_iterate(void **opaque)
Iterate over all registered filters.
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:499
avfilter_config_links
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
AVFilterGraph::opaque
void * opaque
Opaque user data.
Definition: avfilter.h:956
AVFilter::flags_internal
int flags_internal
Additional flags for avfilter internal use only.
Definition: avfilter.h:361
AVFILTER_AUTO_CONVERT_ALL
@ AVFILTER_AUTO_CONVERT_ALL
all automatic conversions enabled
Definition: avfilter.h:1050
avfilter_license
const char * avfilter_license(void)
Return the libavfilter license.
AVFilterContext::input_pads
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:420
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
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:348
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.
avfilter_pad_count
int avfilter_pad_count(const AVFilterPad *pads)
Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
AVFilter::flags
int flags
A combination of AVFILTER_FLAG_*.
Definition: avfilter.h:187
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:972
AVFilterPad
struct AVFilterPad AVFilterPad
Definition: avfilter.h:69
AVFilter::next
struct AVFilter * next
Used by the filter registration system.
Definition: avfilter.h:367
AVFilter::activate
int(* activate)(AVFilterContext *ctx)
Filter activation function.
Definition: avfilter.h:402
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
AVFilterGraph::resample_lavr_opts
attribute_deprecated char * resample_lavr_opts
libavresample options to use for the auto-inserted resample filters
Definition: avfilter.h:922
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
AVFilterContext::thread_type
int thread_type
Type of multithreading being allowed/used.
Definition: avfilter.h:448
avfilter_graph_config
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
AVFilter::outputs
const AVFilterPad * outputs
List of outputs, terminated by a zeroed element.
Definition: avfilter.h:172
avfilter_graph_set_auto_convert
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
Enable or disable automatic format conversion inside the graph.
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterGraph::filters
AVFilterContext ** filters
Definition: avfilter.h:917
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:421
AVFilterContext::name
char * name
name of this filter instance
Definition: avfilter.h:418
avfilter_link_get_channels
attribute_deprecated int avfilter_link_get_channels(AVFilterLink *link)
Get the number of channels of a link.
avfilter_inout_alloc
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
avfilter_graph_get_filter
AVFilterContext * avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
Get a filter instance identified by instance name from graph.
avfilter_graph_request_oldest
int avfilter_graph_request_oldest(AVFilterGraph *graph)
Request a frame on the oldest sink link.
AVFilterGraph
Definition: avfilter.h:915
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.
AVFilterInOut::pad_idx
int pad_idx
index of the filt_ctx pad to use for linking
Definition: avfilter.h:1086
AVFilterGraph::scale_sws_opts
char * scale_sws_opts
sws options to use for the auto-inserted scale filters
Definition: avfilter.h:920
AVFilterContext::nb_inputs
unsigned nb_inputs
number of input pads
Definition: avfilter.h:422
AVFilterGraph::av_class
const AVClass * av_class
Definition: avfilter.h:916
AVMediaType
AVMediaType
Definition: avutil.h:199
AVFilterContext::command_queue
struct AVFilterCommand * command_queue
Definition: avfilter.h:455
AVFilterInOut::filter_ctx
AVFilterContext * filter_ctx
filter context associated to this input/output
Definition: avfilter.h:1083
avfilter_link_set_closed
attribute_deprecated void avfilter_link_set_closed(AVFilterLink *link, int closed)
Set the closed field of a link.
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:912
AVFilter::preinit
int(* preinit)(AVFilterContext *ctx)
Filter pre-initialization function.
Definition: avfilter.h:224
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
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.
frame.h
AVFilter::description
const char * description
A description of the filter.
Definition: avfilter.h:155
avfilter_link_free
void avfilter_link_free(AVFilterLink **link)
Free the link in *link, and set its pointer to NULL.
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:98
attributes.h
AVFilter::nb_inputs
uint8_t nb_inputs
The number of entries in the list of inputs.
Definition: avfilter.h:191
AVFilter::init
int(* init)(AVFilterContext *ctx)
Filter initialization function.
Definition: avfilter.h:247
avfilter_init_str
int avfilter_init_str(AVFilterContext *ctx, const char *args)
Initialize a filter with the supplied parameters.
AVFilter::query_func
int(* query_func)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:326
avfilter_register
attribute_deprecated int avfilter_register(AVFilter *filter)
Register a filter.
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.
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVFilterGraph::thread_type
int thread_type
Type of multithreading allowed for filters in this graph.
Definition: avfilter.h:937
AVFilter::priv_size
int priv_size
size of private data to allocate for the filter
Definition: avfilter.h:359
AVFilter
Filter definition.
Definition: avfilter.h:144
AVFilterGraph::sink_links
AVFilterLink ** sink_links
Private fields.
Definition: avfilter.h:981
pixfmt.h
avfilter_configuration
const char * avfilter_configuration(void)
Return the libavfilter build-time configuration.
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
dict.h
AVFilter::nb_outputs
uint8_t nb_outputs
The number of entries in the list of outputs.
Definition: avfilter.h:196
avfilter_pad_get_type
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
avfilter_init_dict
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
Initialize a filter with the supplied dictionary of options.
version.h
AVFilterContext::enable
void * enable
parsed expression (AVExpr*)
Definition: avfilter.h:458
AVDictionary
struct AVDictionary AVDictionary
Definition: dict.h:86
AVFilter::formats
union AVFilter::@1 formats
AVFilterContext
An instance of a filter.
Definition: avfilter.h:413
AVFILTER_AUTO_CONVERT_NONE
@ AVFILTER_AUTO_CONVERT_NONE
all automatic conversions disabled
Definition: avfilter.h:1051
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.
avutil.h
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:81
AVFilter::init_opaque
int(* init_opaque)(AVFilterContext *ctx, void *opaque)
Filter initialization function, alternative to the init() callback.
Definition: avfilter.h:388
AVFilter::inputs
const AVFilterPad * inputs
List of inputs, terminated by a zeroed element.
Definition: avfilter.h:164
AVFilter::query_formats
int(* query_formats)(AVFilterContext *)
Query formats supported by the filter on its inputs and outputs.
Definition: avfilter.h:296
AVFilter::uninit
void(* uninit)(AVFilterContext *ctx)
Filter uninitialization function.
Definition: avfilter.h:272
avfilter_free
void avfilter_free(AVFilterContext *filter)
Free a filter context.
AVFilter::sample_fmt
enum AVSampleFormat sample_fmt
Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
Definition: avfilter.h:356
AVFilterInOut::name
char * name
unique name for this input/output in the list
Definition: avfilter.h:1080
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.
AVFilterGraphInternal
struct AVFilterGraphInternal AVFilterGraphInternal
Definition: avfilter.h:884
avfilter_next
const attribute_deprecated AVFilter * avfilter_next(const AVFilter *prev)
Iterate over all registered filters.
AVFilterGraph::nb_filters
unsigned nb_filters
Definition: avfilter.h:918
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:416
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:260
avfilter_version
unsigned avfilter_version(void)
Return the LIBAVFILTER_VERSION_INT constant.
avfilter_get_class
const AVClass * avfilter_get_class(void)
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1078
AVFilterGraph::sink_links_count
int sink_links_count
Definition: avfilter.h:982
AVFilterContext::ready
unsigned ready
Ready status of the filter.
Definition: avfilter.h:483
AVFilterInternal
struct AVFilterInternal AVFilterInternal
Definition: avfilter.h:410
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:425