FFmpeg coverage

Line	Branch	Exec	Source
1			/*
2			* Filters implementation helper functions
3			*
4			* This file is part of FFmpeg.
5			*
6			* FFmpeg is free software; you can redistribute it and/or
7			* modify it under the terms of the GNU Lesser General Public License
8			* as published by the Free Software Foundation; either
9			* version 2.1 of the License, or (at your option) any later version.
10			*
11			* FFmpeg is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU Lesser General Public License for more details.
15			*
16			* You should have received a copy of the GNU Lesser General Public License
17			* along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18			* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19			*/
20
21			#ifndef AVFILTER_FILTERS_H
22			#define AVFILTER_FILTERS_H
23
24			/**
25			* Filters implementation helper functions and internal structures
26			*/
27
28			#include "avfilter.h"
29
30			/**
31			* Special return code when activate() did not do anything.
32			*/
33			#define FFERROR_NOT_READY FFERRTAG('N','R','D','Y')
34
35			/**
36			* A filter pad used for either input or output.
37			*/
38			struct AVFilterPad {
39			/**
40			* Pad name. The name is unique among inputs and among outputs, but an
41			* input may have the same name as an output. This may be NULL if this
42			* pad has no need to ever be referenced by name.
43			*/
44			const char *name;
45
46			/**
47			* AVFilterPad type.
48			*/
49			enum AVMediaType type;
50
51			/**
52			* The filter expects writable frames from its input link,
53			* duplicating data buffers if needed.
54			*
55			* input pads only.
56			*/
57			#define AVFILTERPAD_FLAG_NEEDS_WRITABLE (1 << 0)
58
59			/**
60			* The pad's name is allocated and should be freed generically.
61			*/
62			#define AVFILTERPAD_FLAG_FREE_NAME (1 << 1)
63
64			/**
65			* A combination of AVFILTERPAD_FLAG_* flags.
66			*/
67			int flags;
68
69			/**
70			* Callback functions to get a video/audio buffers. If NULL,
71			* the filter system will use ff_default_get_video_buffer() for video
72			* and ff_default_get_audio_buffer() for audio.
73			*
74			* The state of the union is determined by type.
75			*
76			* Input pads only.
77			*/
78			union {
79			AVFrame *(*video)(AVFilterLink *link, int w, int h);
80			AVFrame *(*audio)(AVFilterLink *link, int nb_samples);
81			} get_buffer;
82
83			/**
84			* Filtering callback. This is where a filter receives a frame with
85			* audio/video data and should do its processing.
86			*
87			* Input pads only.
88			*
89			* @return >= 0 on success, a negative AVERROR on error. This function
90			* must ensure that frame is properly unreferenced on error if it
91			* hasn't been passed on to another filter.
92			*/
93			int (*filter_frame)(AVFilterLink *link, AVFrame *frame);
94
95			/**
96			* Frame request callback. A call to this should result in some progress
97			* towards producing output over the given link. This should return zero
98			* on success, and another value on error.
99			*
100			* Output pads only.
101			*/
102			int (*request_frame)(AVFilterLink *link);
103
104			/**
105			* Link configuration callback.
106			*
107			* For output pads, this should set the link properties such as
108			* width/height. This should NOT set the format property - that is
109			* negotiated between filters by the filter system using the
110			* query_formats() callback before this function is called.
111			*
112			* For input pads, this should check the properties of the link, and update
113			* the filter's internal state as necessary.
114			*
115			* For both input and output filters, this should return zero on success,
116			* and another value on error.
117			*/
118			int (*config_props)(AVFilterLink *link);
119			};
120
121			/**
122			* Link properties exposed to filter code, but not external callers.
123			*
124			* Cf. AVFilterLink for public properties, FilterLinkInternal for
125			* properties private to the generic layer.
126			*/
127			typedef struct FilterLink {
128			AVFilterLink pub;
129
130			/**
131			* Graph the filter belongs to.
132			*/
133			struct AVFilterGraph *graph;
134
135			/**
136			* Current timestamp of the link, as defined by the most recent
137			* frame(s), in link time_base units.
138			*/
139			int64_t current_pts;
140
141			/**
142			* Current timestamp of the link, as defined by the most recent
143			* frame(s), in AV_TIME_BASE units.
144			*/
145			int64_t current_pts_us;
146
147			/**
148			* Minimum number of samples to filter at once.
149			*
150			* May be set by the link destination filter in its config_props().
151			* If 0, all related fields are ignored.
152			*/
153			int min_samples;
154
155			/**
156			* Maximum number of samples to filter at once. If filter_frame() is
157			* called with more samples, it will split them.
158			*
159			* May be set by the link destination filter in its config_props().
160			*/
161			int max_samples;
162
163			/**
164			* Number of past frames sent through the link.
165			*/
166			int64_t frame_count_in, frame_count_out;
167
168			/**
169			* Number of past samples sent through the link.
170			*/
171			int64_t sample_count_in, sample_count_out;
172
173			/**
174			* Frame rate of the stream on the link, or 1/0 if unknown or variable.
175			*
176			* May be set by the link source filter in its config_props(); if left to
177			* 0/0, will be automatically copied from the first input of the source
178			* filter if it exists.
179			*
180			* Sources should set it to the best estimation of the real frame rate.
181			* If the source frame rate is unknown or variable, set this to 1/0.
182			* Filters should update it if necessary depending on their function.
183			* Sinks can use it to set a default output frame rate.
184			* It is similar to the r_frame_rate field in AVStream.
185			*/
186			AVRational frame_rate;
187
188			/**
189			* For hwaccel pixel formats, this should be a reference to the
190			* AVHWFramesContext describing the frames.
191			*
192			* May be set by the link source filter in its config_props().
193			*/
194			AVBufferRef *hw_frames_ctx;
195			} FilterLink;
196
197		4504760	static inline FilterLink* ff_filter_link(AVFilterLink *link)
198			{
199		4504760	return (FilterLink*)link;
200			}
201
202			/**
203			* The filter is aware of hardware frames, and any hardware frame context
204			* should not be automatically propagated through it.
205			*/
206			#define FF_FILTER_FLAG_HWFRAME_AWARE (1 << 0)
207
208			/**
209			* Find the index of a link.
210			*
211			* I.e. find i such that link == ctx->(in|out)puts[i]
212			*/
213			#define FF_INLINK_IDX(link) ((int)((link)->dstpad - (link)->dst->input_pads))
214			#define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
215
216			enum FilterFormatsState {
217			/**
218			* The default value meaning that this filter supports all formats
219			* and (for audio) sample rates and channel layouts/counts as long
220			* as these properties agree for all inputs and outputs.
221			* This state is only allowed in case all inputs and outputs actually
222			* have the same type.
223			* The union is unused in this state.
224			*
225			* This value must always be zero (for default static initialization).
226			*/
227			FF_FILTER_FORMATS_PASSTHROUGH = 0,
228			FF_FILTER_FORMATS_QUERY_FUNC, ///< formats.query active.
229			FF_FILTER_FORMATS_QUERY_FUNC2, ///< formats.query_func2 active.
230			FF_FILTER_FORMATS_PIXFMT_LIST, ///< formats.pixels_list active.
231			FF_FILTER_FORMATS_SAMPLEFMTS_LIST, ///< formats.samples_list active.
232			FF_FILTER_FORMATS_SINGLE_PIXFMT, ///< formats.pix_fmt active
233			FF_FILTER_FORMATS_SINGLE_SAMPLEFMT, ///< formats.sample_fmt active.
234			};
235
236			#define FILTER_QUERY_FUNC(func) \
237			.formats.query_func = func, \
238			.formats_state = FF_FILTER_FORMATS_QUERY_FUNC
239			#define FILTER_QUERY_FUNC2(func) \
240			.formats.query_func2 = func, \
241			.formats_state = FF_FILTER_FORMATS_QUERY_FUNC2
242			#define FILTER_PIXFMTS_ARRAY(array) \
243			.formats.pixels_list = array, \
244			.formats_state = FF_FILTER_FORMATS_PIXFMT_LIST
245			#define FILTER_SAMPLEFMTS_ARRAY(array) \
246			.formats.samples_list = array, \
247			.formats_state = FF_FILTER_FORMATS_SAMPLEFMTS_LIST
248			#define FILTER_PIXFMTS(...) \
249			FILTER_PIXFMTS_ARRAY(((const enum AVPixelFormat []) { __VA_ARGS__, AV_PIX_FMT_NONE }))
250			#define FILTER_SAMPLEFMTS(...) \
251			FILTER_SAMPLEFMTS_ARRAY(((const enum AVSampleFormat[]) { __VA_ARGS__, AV_SAMPLE_FMT_NONE }))
252			#define FILTER_SINGLE_PIXFMT(pix_fmt_) \
253			.formats.pix_fmt = pix_fmt_, \
254			.formats_state = FF_FILTER_FORMATS_SINGLE_PIXFMT
255			#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_) \
256			.formats.sample_fmt = sample_fmt_, \
257			.formats_state = FF_FILTER_FORMATS_SINGLE_SAMPLEFMT
258
259			#define FILTER_INOUTPADS(inout, array) \
260			.p.inout = array, \
261			.nb_ ## inout = FF_ARRAY_ELEMS(array)
262			#define FILTER_INPUTS(array) FILTER_INOUTPADS(inputs, (array))
263			#define FILTER_OUTPUTS(array) FILTER_INOUTPADS(outputs, (array))
264
265			typedef struct FFFilter {
266			/**
267			* The public AVFilter. See avfilter.h for it.
268			*/
269			AVFilter p;
270
271			/**
272			* The number of entries in the list of inputs.
273			*/
274			uint8_t nb_inputs;
275
276			/**
277			* The number of entries in the list of outputs.
278			*/
279			uint8_t nb_outputs;
280
281			/**
282			* This field determines the state of the formats union.
283			* It is an enum FilterFormatsState value.
284			*/
285			uint8_t formats_state;
286
287			/**
288			* Filter pre-initialization function
289			*
290			* This callback will be called immediately after the filter context is
291			* allocated, to allow allocating and initing sub-objects.
292			*
293			* If this callback is not NULL, the uninit callback will be called on
294			* allocation failure.
295			*
296			* @return 0 on success,
297			* AVERROR code on failure (but the code will be
298			* dropped and treated as ENOMEM by the calling code)
299			*/
300			int (*preinit)(AVFilterContext *ctx);
301
302			/**
303			* Filter initialization function.
304			*
305			* This callback will be called only once during the filter lifetime, after
306			* all the options have been set, but before links between filters are
307			* established and format negotiation is done.
308			*
309			* Basic filter initialization should be done here. Filters with dynamic
310			* inputs and/or outputs should create those inputs/outputs here based on
311			* provided options. No more changes to this filter's inputs/outputs can be
312			* done after this callback.
313			*
314			* This callback must not assume that the filter links exist or frame
315			* parameters are known.
316			*
317			* @ref AVFilter.uninit "uninit" is guaranteed to be called even if
318			* initialization fails, so this callback does not have to clean up on
319			* failure.
320			*
321			* @return 0 on success, a negative AVERROR on failure
322			*/
323			int (*init)(AVFilterContext *ctx);
324
325			/**
326			* Filter uninitialization function.
327			*
328			* Called only once right before the filter is freed. Should deallocate any
329			* memory held by the filter, release any buffer references, etc. It does
330			* not need to deallocate the AVFilterContext.priv memory itself.
331			*
332			* This callback may be called even if @ref AVFilter.init "init" was not
333			* called or failed, so it must be prepared to handle such a situation.
334			*/
335			void (*uninit)(AVFilterContext *ctx);
336
337			/**
338			* The state of the following union is determined by formats_state.
339			* See the documentation of enum FilterFormatsState in internal.h.
340			*/
341			union {
342			/**
343			* Query formats supported by the filter on its inputs and outputs.
344			*
345			* This callback is called after the filter is initialized (so the inputs
346			* and outputs are fixed), shortly before the format negotiation. This
347			* callback may be called more than once.
348			*
349			* This callback must set ::AVFilterLink's
350			* @ref AVFilterFormatsConfig.formats "outcfg.formats"
351			* on every input link and
352			* @ref AVFilterFormatsConfig.formats "incfg.formats"
353			* on every output link to a list of pixel/sample formats that the filter
354			* supports on that link.
355			* For video links, this filter may also set
356			* @ref AVFilterFormatsConfig.color_spaces "incfg.color_spaces"
357			* /
358			* @ref AVFilterFormatsConfig.color_spaces "outcfg.color_spaces"
359			* and @ref AVFilterFormatsConfig.color_ranges "incfg.color_ranges"
360			* /
361			* @ref AVFilterFormatsConfig.color_ranges "outcfg.color_ranges"
362			* analogously.
363			* For audio links, this filter must also set
364			* @ref AVFilterFormatsConfig.samplerates "incfg.samplerates"
365			* /
366			* @ref AVFilterFormatsConfig.samplerates "outcfg.samplerates"
367			* and @ref AVFilterFormatsConfig.channel_layouts "incfg.channel_layouts"
368			* /
369			* @ref AVFilterFormatsConfig.channel_layouts "outcfg.channel_layouts"
370			* analogously.
371			*
372			* This callback must never be NULL if the union is in this state.
373			*
374			* @return zero on success, a negative value corresponding to an
375			* AVERROR code otherwise
376			*/
377			int (*query_func)(AVFilterContext *);
378
379			/**
380			* Same as query_func(), except this function writes the results into
381			* provided arrays.
382			*
383			* @param cfg_in array of input format configurations with as many
384			* members as the filters has inputs (NULL when there are
385			* no inputs);
386			* @param cfg_out array of output format configurations with as many
387			* members as the filters has outputs (NULL when there
388			* are no outputs);
389			*/
390			int (*query_func2)(const AVFilterContext *,
391			struct AVFilterFormatsConfig **cfg_in,
392			struct AVFilterFormatsConfig **cfg_out);
393			/**
394			* A pointer to an array of admissible pixel formats delimited
395			* by AV_PIX_FMT_NONE. The generic code will use this list
396			* to indicate that this filter supports each of these pixel formats,
397			* provided that all inputs and outputs use the same pixel format.
398			*
399			* In addition to that the generic code will mark all inputs
400			* and all outputs as supporting all color spaces and ranges, as
401			* long as all inputs and outputs use the same color space/range.
402			*
403			* This list must never be NULL if the union is in this state.
404			* The type of all inputs and outputs of filters using this must
405			* be AVMEDIA_TYPE_VIDEO.
406			*/
407			const enum AVPixelFormat *pixels_list;
408			/**
409			* Analogous to pixels, but delimited by AV_SAMPLE_FMT_NONE
410			* and restricted to filters that only have AVMEDIA_TYPE_AUDIO
411			* inputs and outputs.
412			*
413			* In addition to that the generic code will mark all inputs
414			* and all outputs as supporting all sample rates and every
415			* channel count and channel layout, as long as all inputs
416			* and outputs use the same sample rate and channel count/layout.
417			*/
418			const enum AVSampleFormat *samples_list;
419			/**
420			* Equivalent to { pix_fmt, AV_PIX_FMT_NONE } as pixels_list.
421			*/
422			enum AVPixelFormat pix_fmt;
423			/**
424			* Equivalent to { sample_fmt, AV_SAMPLE_FMT_NONE } as samples_list.
425			*/
426			enum AVSampleFormat sample_fmt;
427			} formats;
428
429			int priv_size; ///< size of private data to allocate for the filter
430
431			int flags_internal; ///< Additional flags for avfilter internal use only.
432
433			/**
434			* Make the filter instance process a command.
435			*
436			* @param cmd the command to process, for handling simplicity all commands must be alphanumeric only
437			* @param arg the argument for the command
438			* @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.
439			* @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be
440			* time consuming then a filter should treat it like an unsupported command
441			*
442			* @returns >=0 on success otherwise an error code.
443			* AVERROR(ENOSYS) on unsupported commands
444			*/
445			int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);
446
447			/**
448			* Filter activation function.
449			*
450			* Called when any processing is needed from the filter, instead of any
451			* filter_frame and request_frame on pads.
452			*
453			* The function must examine inlinks and outlinks and perform a single
454			* step of processing. If there is nothing to do, the function must do
455			* nothing and not return an error. If more steps are or may be
456			* possible, it must use ff_filter_set_ready() to schedule another
457			* activation.
458			*/
459			int (*activate)(AVFilterContext *ctx);
460			} FFFilter;
461
462		5158829	static inline const FFFilter *fffilter(const AVFilter *f)
463			{
464		5158829	return (const FFFilter*)f;
465			}
466
467
468			#define AVFILTER_DEFINE_CLASS_EXT(name, desc, options) \
469			static const AVClass name##_class = { \
470			.class_name = desc, \
471			.item_name = av_default_item_name, \
472			.option = options, \
473			.version = LIBAVUTIL_VERSION_INT, \
474			.category = AV_CLASS_CATEGORY_FILTER, \
475			}
476			#define AVFILTER_DEFINE_CLASS(fname) \
477			AVFILTER_DEFINE_CLASS_EXT(fname, #fname, fname##_options)
478
479			#define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d))
480			#define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
481			#define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts) * av_q2d(tb))
482
483			/**
484			* Mark a filter ready and schedule it for activation.
485			*
486			* This is automatically done when something happens to the filter (queued
487			* frame, status change, request on output).
488			* Filters implementing the activate callback can call it directly to
489			* perform one more round of processing later.
490			* It is also useful for filters reacting to external or asynchronous
491			* events.
492			*/
493			void ff_filter_set_ready(AVFilterContext *filter, unsigned priority);
494
495			/**
496			* Get the number of frames available on the link.
497			* @return the number of frames available in the link fifo.
498			*/
499			size_t ff_inlink_queued_frames(AVFilterLink *link);
500
501			/**
502			* Test if a frame is available on the link.
503			* @return >0 if a frame is available
504			*/
505			int ff_inlink_check_available_frame(AVFilterLink *link);
506
507
508			/***
509			* Get the number of samples available on the link.
510			* @return the numer of samples available on the link.
511			*/
512			int ff_inlink_queued_samples(AVFilterLink *link);
513
514			/**
515			* Test if enough samples are available on the link.
516			* @return >0 if enough samples are available
517			* @note on EOF and error, min becomes 1
518			*/
519			int ff_inlink_check_available_samples(AVFilterLink *link, unsigned min);
520
521			/**
522			* Take a frame from the link's FIFO and update the link's stats.
523			*
524			* If ff_inlink_check_available_frame() was previously called, the
525			* preferred way of expressing it is "av_assert1(ret);" immediately after
526			* ff_inlink_consume_frame(). Negative error codes must still be checked.
527			*
528			* @note May trigger process_command() and/or update is_disabled.
529			* @return >0 if a frame is available,
530			* 0 and set rframe to NULL if no frame available,
531			* or AVERROR code
532			*/
533			int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe);
534
535			/**
536			* Take samples from the link's FIFO and update the link's stats.
537			*
538			* If ff_inlink_check_available_samples() was previously called, the
539			* preferred way of expressing it is "av_assert1(ret);" immediately after
540			* ff_inlink_consume_samples(). Negative error codes must still be checked.
541			*
542			* @note May trigger process_command() and/or update is_disabled.
543			* @return >0 if a frame is available,
544			* 0 and set rframe to NULL if no frame available,
545			* or AVERROR code
546			*/
547			int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max,
548			AVFrame **rframe);
549
550			/**
551			* Access a frame in the link fifo without consuming it.
552			* The first frame is numbered 0; the designated frame must exist.
553			* @return the frame at idx position in the link fifo.
554			*/
555			AVFrame *ff_inlink_peek_frame(AVFilterLink *link, size_t idx);
556
557			/**
558			* Make sure a frame is writable.
559			* This is similar to av_frame_make_writable() except it uses the link's
560			* buffer allocation callback, and therefore allows direct rendering.
561			*/
562			int ff_inlink_make_frame_writable(AVFilterLink *link, AVFrame **rframe);
563
564			/**
565			* Test and acknowledge the change of status on the link.
566			*
567			* Status means EOF or an error condition; a change from the normal (0)
568			* status to a non-zero status can be queued in a filter's input link, it
569			* becomes relevant after the frames queued in the link's FIFO are
570			* processed. This function tests if frames are still queued and if a queued
571			* status change has not yet been processed. In that case it performs basic
572			* treatment (updating the link's timestamp) and returns a positive value to
573			* let the filter do its own treatments (flushing...).
574			*
575			* Filters implementing the activate callback should call this function when
576			* they think it might succeed (usually after checking unsuccessfully for a
577			* queued frame).
578			* Filters implementing the filter_frame and request_frame callbacks do not
579			* need to call that since the same treatment happens in ff_filter_frame().
580			*
581			* @param[out] rstatus new or current status
582			* @param[out] rpts current timestamp of the link in link time base
583			* @return >0 if status changed, <0 if status already acked, 0 otherwise
584			*/
585			int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts);
586
587			/**
588			* Mark that a frame is wanted on the link.
589			* Unlike ff_filter_frame(), it must not be called when the link has a
590			* non-zero status, and thus does not acknowledge it.
591			* Also it cannot fail.
592			*/
593			void ff_inlink_request_frame(AVFilterLink *link);
594
595			/**
596			* Set the status on an input link.
597			* Also discard all frames in the link's FIFO.
598			*/
599			void ff_inlink_set_status(AVFilterLink *link, int status);
600
601			/**
602			* Test if a frame is wanted on an output link.
603			*/
604			int ff_outlink_frame_wanted(AVFilterLink *link);
605
606			/**
607			* Get the status on an output link.
608			*/
609			int ff_outlink_get_status(AVFilterLink *link);
610
611			/**
612			* Set the status field of a link from the source filter.
613			* The pts should reflect the timestamp of the status change,
614			* in link time base and relative to the frames timeline.
615			* In particular, for AVERROR_EOF, it should reflect the
616			* end time of the last frame.
617			*/
618			void ff_avfilter_link_set_in_status(AVFilterLink *link, int status, int64_t pts);
619
620			/**
621			* Set the status field of a link from the source filter.
622			* The pts should reflect the timestamp of the status change,
623			* in link time base and relative to the frames timeline.
624			* In particular, for AVERROR_EOF, it should reflect the
625			* end time of the last frame.
626			*/
627		7987	static inline void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
628			{
629		7987	ff_avfilter_link_set_in_status(link, status, pts);
630		7987	}
631
632			/**
633			* Forward the status on an output link to an input link.
634			* If the status is set, it will discard all queued frames and this macro
635			* will return immediately.
636			*/
637			#define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink) do { \
638			int ret = ff_outlink_get_status(outlink); \
639			if (ret) { \
640			ff_inlink_set_status(inlink, ret); \
641			return 0; \
642			} \
643			} while (0)
644
645			/**
646			* Forward the status on an output link to all input links.
647			* If the status is set, it will discard all queued frames and this macro
648			* will return immediately.
649			*/
650			#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter) do { \
651			int ret = ff_outlink_get_status(outlink); \
652			if (ret) { \
653			unsigned i; \
654			for (i = 0; i < filter->nb_inputs; i++) \
655			ff_inlink_set_status(filter->inputs[i], ret); \
656			return 0; \
657			} \
658			} while (0)
659
660			/**
661			* Acknowledge the status on an input link and forward it to an output link.
662			* If the status is set, this macro will return immediately.
663			*/
664			#define FF_FILTER_FORWARD_STATUS(inlink, outlink) do { \
665			int status; \
666			int64_t pts; \
667			if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
668			ff_outlink_set_status(outlink, status, pts); \
669			return 0; \
670			} \
671			} while (0)
672
673			/**
674			* Acknowledge the status on an input link and forward it to an output link.
675			* If the status is set, this macro will return immediately.
676			*/
677			#define FF_FILTER_FORWARD_STATUS_ALL(inlink, filter) do { \
678			int status; \
679			int64_t pts; \
680			if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
681			unsigned i; \
682			for (i = 0; i < filter->nb_outputs; i++) \
683			ff_outlink_set_status(filter->outputs[i], status, pts); \
684			return 0; \
685			} \
686			} while (0)
687
688			/**
689			* Forward the frame_wanted_out flag from an output link to an input link.
690			* If the flag is set, this macro will return immediately.
691			*/
692			#define FF_FILTER_FORWARD_WANTED(outlink, inlink) do { \
693			if (ff_outlink_frame_wanted(outlink)) { \
694			ff_inlink_request_frame(inlink); \
695			return 0; \
696			} \
697			} while (0)
698
699			/**
700			* Check for flow control between input and output.
701			* This is necessary for filters that may produce several output frames for
702			* a single input event, otherwise they may produce them all at once,
703			* causing excessive memory consumption.
704			*/
705			int ff_inoutlink_check_flow(AVFilterLink *inlink, AVFilterLink *outlink);
706
707			/**
708			* Perform any additional setup required for hardware frames.
709			*
710			* link->hw_frames_ctx must be set before calling this function.
711			* Inside link->hw_frames_ctx, the fields format, sw_format, width and
712			* height must be set. If dynamically allocated pools are not supported,
713			* then initial_pool_size must also be set, to the minimum hardware frame
714			* pool size necessary for the filter to work (taking into account any
715			* frames which need to stored for use in operations as appropriate). If
716			* default_pool_size is nonzero, then it will be used as the pool size if
717			* no other modification takes place (this can be used to preserve
718			* compatibility).
719			*/
720			int ff_filter_init_hw_frames(AVFilterContext *avctx, AVFilterLink *link,
721			int default_pool_size);
722
723			/**
724			* Generic processing of user supplied commands that are set
725			* in the same way as the filter options.
726			* NOTE: 'enable' option is handled separately, and not by
727			* this function.
728			*/
729			int ff_filter_process_command(AVFilterContext *ctx, const char *cmd,
730			const char *arg, char *res, int res_len, int flags);
731
732			/**
733			* Get number of threads for current filter instance.
734			* This number is always same or less than graph->nb_threads.
735			*/
736			int ff_filter_get_nb_threads(AVFilterContext *ctx) av_pure;
737
738			/**
739			* Send a frame of data to the next filter.
740			*
741			* @param link the output link over which the data is being sent
742			* @param frame a reference to the buffer of data being sent. The
743			* receiving filter will free this reference when it no longer
744			* needs it or pass it on to the next filter.
745			*
746			* @return >= 0 on success, a negative AVERROR on error. The receiving filter
747			* is responsible for unreferencing frame in case of error.
748			*/
749			int ff_filter_frame(AVFilterLink *link, AVFrame *frame);
750
751			/**
752			* Request an input frame from the filter at the other end of the link.
753			*
754			* This function must not be used by filters using the activate callback,
755			* use ff_link_set_frame_wanted() instead.
756			*
757			* The input filter may pass the request on to its inputs, fulfill the
758			* request from an internal buffer or any other means specific to its function.
759			*
760			* When the end of a stream is reached AVERROR_EOF is returned and no further
761			* frames are returned after that.
762			*
763			* When a filter is unable to output a frame for example due to its sources
764			* being unable to do so or because it depends on external means pushing data
765			* into it then AVERROR(EAGAIN) is returned.
766			* It is important that a AVERROR(EAGAIN) return is returned all the way to the
767			* caller (generally eventually a user application) as this step may (but does
768			* not have to be) necessary to provide the input with the next frame.
769			*
770			* If a request is successful then some progress has been made towards
771			* providing a frame on the link (through ff_filter_frame()). A filter that
772			* needs several frames to produce one is allowed to return success if one
773			* more frame has been processed but no output has been produced yet. A
774			* filter is also allowed to simply forward a success return value.
775			*
776			* @param link the input link
777			* @return zero on success
778			* AVERROR_EOF on end of file
779			* AVERROR(EAGAIN) if the previous filter cannot output a frame
780			* currently and can neither guarantee that EOF has been reached.
781			*/
782			int ff_request_frame(AVFilterLink *link);
783
784			/**
785			* Append a new input/output pad to the filter's list of such pads.
786			*
787			* The *_free_name versions will set the AVFILTERPAD_FLAG_FREE_NAME flag
788			* ensuring that the name will be freed generically (even on insertion error).
789			*/
790			int ff_append_inpad (AVFilterContext *f, AVFilterPad *p);
791			int ff_append_outpad(AVFilterContext *f, AVFilterPad *p);
792			int ff_append_inpad_free_name (AVFilterContext *f, AVFilterPad *p);
793			int ff_append_outpad_free_name(AVFilterContext *f, AVFilterPad *p);
794
795			/**
796			* Tell if an integer is contained in the provided -1-terminated list of integers.
797			* This is useful for determining (for instance) if an AVPixelFormat is in an
798			* array of supported formats.
799			*
800			* @param fmt provided format
801			* @param fmts -1-terminated list of formats
802			* @return 1 if present, 0 if absent
803			*/
804			int ff_fmt_is_in(int fmt, const int *fmts);
805
806			int ff_filter_execute(AVFilterContext *ctx, avfilter_action_func *func,
807			void *arg, int *ret, int nb_jobs);
808
809			#endif /* AVFILTER_FILTERS_H */
810