Implement avfilter_copy_picref_props().
[libav.git] / libavfilter / avfilter.h
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 #include "libavutil/avutil.h"
26
27 #define LIBAVFILTER_VERSION_MAJOR 1
28 #define LIBAVFILTER_VERSION_MINOR 21
29 #define LIBAVFILTER_VERSION_MICRO 0
30
31 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
32 LIBAVFILTER_VERSION_MINOR, \
33 LIBAVFILTER_VERSION_MICRO)
34 #define LIBAVFILTER_VERSION AV_VERSION(LIBAVFILTER_VERSION_MAJOR, \
35 LIBAVFILTER_VERSION_MINOR, \
36 LIBAVFILTER_VERSION_MICRO)
37 #define LIBAVFILTER_BUILD LIBAVFILTER_VERSION_INT
38
39 #include <stddef.h>
40 #include "libavcodec/avcodec.h"
41
42 /**
43 * Return the LIBAVFILTER_VERSION_INT constant.
44 */
45 unsigned avfilter_version(void);
46
47 /**
48 * Return the libavfilter build-time configuration.
49 */
50 const char *avfilter_configuration(void);
51
52 /**
53 * Return the libavfilter license.
54 */
55 const char *avfilter_license(void);
56
57
58 typedef struct AVFilterContext AVFilterContext;
59 typedef struct AVFilterLink AVFilterLink;
60 typedef struct AVFilterPad AVFilterPad;
61
62 /* TODO: look for other flags which may be useful in this structure (interlace
63 * flags, etc)
64 */
65 /**
66 * A reference-counted picture data type used by the filter system. Filters
67 * should not store pointers to this structure directly, but instead use the
68 * AVFilterPicRef structure below.
69 */
70 typedef struct AVFilterPic
71 {
72 uint8_t *data[4]; ///< picture data for each plane
73 int linesize[4]; ///< number of bytes per line
74 enum PixelFormat format; ///< colorspace
75
76 unsigned refcount; ///< number of references to this image
77
78 /** private data to be used by a custom free function */
79 void *priv;
80 /**
81 * A pointer to the function to deallocate this image if the default
82 * function is not sufficient. This could, for example, add the memory
83 * back into a memory pool to be reused later without the overhead of
84 * reallocating it from scratch.
85 */
86 void (*free)(struct AVFilterPic *pic);
87
88 int w, h; ///< width and height of the allocated buffer
89 } AVFilterPic;
90
91 /**
92 * A reference to an AVFilterPic. Since filters can manipulate the origin of
93 * a picture to, for example, crop image without any memcpy, the picture origin
94 * and dimensions are per-reference properties. Linesize is also useful for
95 * image flipping, frame to field filters, etc, and so is also per-reference.
96 *
97 * TODO: add anything necessary for frame reordering
98 */
99 typedef struct AVFilterPicRef
100 {
101 AVFilterPic *pic; ///< the picture that this is a reference to
102 uint8_t *data[4]; ///< picture data for each plane
103 int linesize[4]; ///< number of bytes per line
104 int w; ///< image width
105 int h; ///< image height
106
107 int64_t pts; ///< presentation timestamp in units of 1/AV_TIME_BASE
108 int64_t pos; ///< byte position in stream, -1 if unknown
109
110 AVRational pixel_aspect; ///< pixel aspect ratio
111
112 int perms; ///< permissions
113 #define AV_PERM_READ 0x01 ///< can read from the buffer
114 #define AV_PERM_WRITE 0x02 ///< can write to the buffer
115 #define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer
116 #define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time
117 #define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time
118
119 int interlaced; ///< is frame interlaced
120 int top_field_first;
121 } AVFilterPicRef;
122
123 /**
124 * Copy properties of src to dst, without copying the actual video
125 * data.
126 */
127 static inline void avfilter_copy_picref_props(AVFilterPicRef *dst, AVFilterPicRef *src)
128 {
129 dst->pts = src->pts;
130 dst->pos = src->pos;
131 dst->pixel_aspect = src->pixel_aspect;
132 dst->interlaced = src->interlaced;
133 dst->top_field_first = src->top_field_first;
134 }
135
136 /**
137 * Add a new reference to a picture.
138 * @param ref an existing reference to the picture
139 * @param pmask a bitmask containing the allowable permissions in the new
140 * reference
141 * @return a new reference to the picture with the same properties as the
142 * old, excluding any permissions denied by pmask
143 */
144 AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask);
145
146 /**
147 * Remove a reference to a picture. If this is the last reference to the
148 * picture, the picture itself is also automatically freed.
149 * @param ref reference to the picture
150 */
151 void avfilter_unref_pic(AVFilterPicRef *ref);
152
153 /**
154 * A list of supported formats for one end of a filter link. This is used
155 * during the format negotiation process to try to pick the best format to
156 * use to minimize the number of necessary conversions. Each filter gives a
157 * list of the formats supported by each input and output pad. The list
158 * given for each pad need not be distinct - they may be references to the
159 * same list of formats, as is often the case when a filter supports multiple
160 * formats, but will always output the same format as it is given in input.
161 *
162 * In this way, a list of possible input formats and a list of possible
163 * output formats are associated with each link. When a set of formats is
164 * negotiated over a link, the input and output lists are merged to form a
165 * new list containing only the common elements of each list. In the case
166 * that there were no common elements, a format conversion is necessary.
167 * Otherwise, the lists are merged, and all other links which reference
168 * either of the format lists involved in the merge are also affected.
169 *
170 * For example, consider the filter chain:
171 * filter (a) --> (b) filter (b) --> (c) filter
172 *
173 * where the letters in parenthesis indicate a list of formats supported on
174 * the input or output of the link. Suppose the lists are as follows:
175 * (a) = {A, B}
176 * (b) = {A, B, C}
177 * (c) = {B, C}
178 *
179 * First, the first link's lists are merged, yielding:
180 * filter (a) --> (a) filter (a) --> (c) filter
181 *
182 * Notice that format list (b) now refers to the same list as filter list (a).
183 * Next, the lists for the second link are merged, yielding:
184 * filter (a) --> (a) filter (a) --> (a) filter
185 *
186 * where (a) = {B}.
187 *
188 * Unfortunately, when the format lists at the two ends of a link are merged,
189 * we must ensure that all links which reference either pre-merge format list
190 * get updated as well. Therefore, we have the format list structure store a
191 * pointer to each of the pointers to itself.
192 */
193 typedef struct AVFilterFormats AVFilterFormats;
194 struct AVFilterFormats
195 {
196 unsigned format_count; ///< number of formats
197 enum PixelFormat *formats; ///< list of pixel formats
198
199 unsigned refcount; ///< number of references to this list
200 AVFilterFormats ***refs; ///< references to this list
201 };
202
203 /**
204 * Create a list of supported formats. This is intended for use in
205 * AVFilter->query_formats().
206 * @param pix_fmts list of pixel formats, terminated by PIX_FMT_NONE
207 * @return the format list, with no existing references
208 */
209 AVFilterFormats *avfilter_make_format_list(const enum PixelFormat *pix_fmts);
210
211 /**
212 * Add pix_fmt to the list of pixel formats contained in *avff.
213 * If *avff is NULL the function allocates the filter formats struct
214 * and puts its pointer in *avff.
215 *
216 * @return a non negative value in case of success, or a negative
217 * value corresponding to an AVERROR code in case of error
218 */
219 int avfilter_add_colorspace(AVFilterFormats **avff, enum PixelFormat pix_fmt);
220
221 /**
222 * Return a list of all colorspaces supported by FFmpeg.
223 */
224 AVFilterFormats *avfilter_all_colorspaces(void);
225
226 /**
227 * Return a format list which contains the intersection of the formats of
228 * a and b. Also, all the references of a, all the references of b, and
229 * a and b themselves will be deallocated.
230 *
231 * If a and b do not share any common formats, neither is modified, and NULL
232 * is returned.
233 */
234 AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b);
235
236 /**
237 * Add *ref as a new reference to formats.
238 * That is the pointers will point like in the ascii art below:
239 * ________
240 * |formats |<--------.
241 * | ____ | ____|___________________
242 * | |refs| | | __|_
243 * | |* * | | | | | | AVFilterLink
244 * | |* *--------->|*ref|
245 * | |____| | | |____|
246 * |________| |________________________
247 */
248 void avfilter_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref);
249
250 /**
251 * If *ref is non-NULL, remove *ref as a reference to the format list
252 * it currently points to, deallocates that list if this was the last
253 * reference, and sets *ref to NULL.
254 *
255 * Before After
256 * ________ ________ NULL
257 * |formats |<--------. |formats | ^
258 * | ____ | ____|________________ | ____ | ____|________________
259 * | |refs| | | __|_ | |refs| | | __|_
260 * | |* * | | | | | | AVFilterLink | |* * | | | | | | AVFilterLink
261 * | |* *--------->|*ref| | |* | | | |*ref|
262 * | |____| | | |____| | |____| | | |____|
263 * |________| |_____________________ |________| |_____________________
264 */
265 void avfilter_formats_unref(AVFilterFormats **ref);
266
267 /**
268 *
269 * Before After
270 * ________ ________
271 * |formats |<---------. |formats |<---------.
272 * | ____ | ___|___ | ____ | ___|___
273 * | |refs| | | | | | |refs| | | | | NULL
274 * | |* *--------->|*oldref| | |* *--------->|*newref| ^
275 * | |* * | | |_______| | |* * | | |_______| ___|___
276 * | |____| | | |____| | | | |
277 * |________| |________| |*oldref|
278 * |_______|
279 */
280 void avfilter_formats_changeref(AVFilterFormats **oldref,
281 AVFilterFormats **newref);
282
283 /**
284 * A filter pad used for either input or output.
285 */
286 struct AVFilterPad
287 {
288 /**
289 * Pad name. The name is unique among inputs and among outputs, but an
290 * input may have the same name as an output. This may be NULL if this
291 * pad has no need to ever be referenced by name.
292 */
293 const char *name;
294
295 /**
296 * AVFilterPad type. Only video supported now, hopefully someone will
297 * add audio in the future.
298 */
299 enum AVMediaType type;
300
301 /**
302 * Minimum required permissions on incoming buffers. Any buffer with
303 * insufficient permissions will be automatically copied by the filter
304 * system to a new buffer which provides the needed access permissions.
305 *
306 * Input pads only.
307 */
308 int min_perms;
309
310 /**
311 * Permissions which are not accepted on incoming buffers. Any buffer
312 * which has any of these permissions set will be automatically copied
313 * by the filter system to a new buffer which does not have those
314 * permissions. This can be used to easily disallow buffers with
315 * AV_PERM_REUSE.
316 *
317 * Input pads only.
318 */
319 int rej_perms;
320
321 /**
322 * Callback called before passing the first slice of a new frame. If
323 * NULL, the filter layer will default to storing a reference to the
324 * picture inside the link structure.
325 *
326 * Input video pads only.
327 */
328 void (*start_frame)(AVFilterLink *link, AVFilterPicRef *picref);
329
330 /**
331 * Callback function to get a buffer. If NULL, the filter system will
332 * use avfilter_default_get_video_buffer().
333 *
334 * Input video pads only.
335 */
336 AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms, int w, int h);
337
338 /**
339 * Callback called after the slices of a frame are completely sent. If
340 * NULL, the filter layer will default to releasing the reference stored
341 * in the link structure during start_frame().
342 *
343 * Input video pads only.
344 */
345 void (*end_frame)(AVFilterLink *link);
346
347 /**
348 * Slice drawing callback. This is where a filter receives video data
349 * and should do its processing.
350 *
351 * Input video pads only.
352 */
353 void (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir);
354
355 /**
356 * Frame poll callback. This returns the number of immediately available
357 * frames. It should return a positive value if the next request_frame()
358 * is guaranteed to return one frame (with no delay).
359 *
360 * Defaults to just calling the source poll_frame() method.
361 *
362 * Output video pads only.
363 */
364 int (*poll_frame)(AVFilterLink *link);
365
366 /**
367 * Frame request callback. A call to this should result in at least one
368 * frame being output over the given link. This should return zero on
369 * success, and another value on error.
370 *
371 * Output video pads only.
372 */
373 int (*request_frame)(AVFilterLink *link);
374
375 /**
376 * Link configuration callback.
377 *
378 * For output pads, this should set the link properties such as
379 * width/height. This should NOT set the format property - that is
380 * negotiated between filters by the filter system using the
381 * query_formats() callback before this function is called.
382 *
383 * For input pads, this should check the properties of the link, and update
384 * the filter's internal state as necessary.
385 *
386 * For both input and output filters, this should return zero on success,
387 * and another value on error.
388 */
389 int (*config_props)(AVFilterLink *link);
390 };
391
392 /** default handler for start_frame() for video inputs */
393 void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
394 /** default handler for draw_slice() for video inputs */
395 void avfilter_default_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
396 /** default handler for end_frame() for video inputs */
397 void avfilter_default_end_frame(AVFilterLink *link);
398 /** default handler for config_props() for video outputs */
399 int avfilter_default_config_output_link(AVFilterLink *link);
400 /** default handler for config_props() for video inputs */
401 int avfilter_default_config_input_link (AVFilterLink *link);
402 /** default handler for get_video_buffer() for video inputs */
403 AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link,
404 int perms, int w, int h);
405 /**
406 * A helper for query_formats() which sets all links to the same list of
407 * formats. If there are no links hooked to this filter, the list of formats is
408 * freed.
409 */
410 void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats);
411 /** Default handler for query_formats() */
412 int avfilter_default_query_formats(AVFilterContext *ctx);
413
414 /** start_frame() handler for filters which simply pass video along */
415 void avfilter_null_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
416
417 /** draw_slice() handler for filters which simply pass video along */
418 void avfilter_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
419
420 /** end_frame() handler for filters which simply pass video along */
421 void avfilter_null_end_frame(AVFilterLink *link);
422
423 /** get_video_buffer() handler for filters which simply pass video along */
424 AVFilterPicRef *avfilter_null_get_video_buffer(AVFilterLink *link,
425 int perms, int w, int h);
426
427 /**
428 * Filter definition. This defines the pads a filter contains, and all the
429 * callback functions used to interact with the filter.
430 */
431 typedef struct AVFilter
432 {
433 const char *name; ///< filter name
434
435 int priv_size; ///< size of private data to allocate for the filter
436
437 /**
438 * Filter initialization function. Args contains the user-supplied
439 * parameters. FIXME: maybe an AVOption-based system would be better?
440 * opaque is data provided by the code requesting creation of the filter,
441 * and is used to pass data to the filter.
442 */
443 int (*init)(AVFilterContext *ctx, const char *args, void *opaque);
444
445 /**
446 * Filter uninitialization function. Should deallocate any memory held
447 * by the filter, release any picture references, etc. This does not need
448 * to deallocate the AVFilterContext->priv memory itself.
449 */
450 void (*uninit)(AVFilterContext *ctx);
451
452 /**
453 * Queries formats supported by the filter and its pads, and sets the
454 * in_formats for links connected to its output pads, and out_formats
455 * for links connected to its input pads.
456 *
457 * @return zero on success, a negative value corresponding to an
458 * AVERROR code otherwise
459 */
460 int (*query_formats)(AVFilterContext *);
461
462 const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none
463 const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none
464
465 /**
466 * A description for the filter. You should use the
467 * NULL_IF_CONFIG_SMALL() macro to define it.
468 */
469 const char *description;
470 } AVFilter;
471
472 /** An instance of a filter */
473 struct AVFilterContext
474 {
475 const AVClass *av_class; ///< needed for av_log()
476
477 AVFilter *filter; ///< the AVFilter of which this is an instance
478
479 char *name; ///< name of this filter instance
480
481 unsigned input_count; ///< number of input pads
482 AVFilterPad *input_pads; ///< array of input pads
483 AVFilterLink **inputs; ///< array of pointers to input links
484
485 unsigned output_count; ///< number of output pads
486 AVFilterPad *output_pads; ///< array of output pads
487 AVFilterLink **outputs; ///< array of pointers to output links
488
489 void *priv; ///< private data for use by the filter
490 };
491
492 /**
493 * A link between two filters. This contains pointers to the source and
494 * destination filters between which this link exists, and the indexes of
495 * the pads involved. In addition, this link also contains the parameters
496 * which have been negotiated and agreed upon between the filter, such as
497 * image dimensions, format, etc.
498 */
499 struct AVFilterLink
500 {
501 AVFilterContext *src; ///< source filter
502 unsigned int srcpad; ///< index of the output pad on the source filter
503
504 AVFilterContext *dst; ///< dest filter
505 unsigned int dstpad; ///< index of the input pad on the dest filter
506
507 /** stage of the initialization of the link properties (dimensions, etc) */
508 enum {
509 AVLINK_UNINIT = 0, ///< not started
510 AVLINK_STARTINIT, ///< started, but incomplete
511 AVLINK_INIT ///< complete
512 } init_state;
513
514 int w; ///< agreed upon image width
515 int h; ///< agreed upon image height
516 enum PixelFormat format; ///< agreed upon image colorspace
517
518 /**
519 * Lists of formats supported by the input and output filters respectively.
520 * These lists are used for negotiating the format to actually be used,
521 * which will be loaded into the format member, above, when chosen.
522 */
523 AVFilterFormats *in_formats;
524 AVFilterFormats *out_formats;
525
526 /**
527 * The picture reference currently being sent across the link by the source
528 * filter. This is used internally by the filter system to allow
529 * automatic copying of pictures which do not have sufficient permissions
530 * for the destination. This should not be accessed directly by the
531 * filters.
532 */
533 AVFilterPicRef *srcpic;
534
535 AVFilterPicRef *cur_pic;
536 AVFilterPicRef *outpic;
537 };
538
539 /**
540 * Link two filters together.
541 * @param src the source filter
542 * @param srcpad index of the output pad on the source filter
543 * @param dst the destination filter
544 * @param dstpad index of the input pad on the destination filter
545 * @return zero on success
546 */
547 int avfilter_link(AVFilterContext *src, unsigned srcpad,
548 AVFilterContext *dst, unsigned dstpad);
549
550 /**
551 * Negotiate the colorspace, dimensions, etc of all inputs to a filter.
552 * @param filter the filter to negotiate the properties for its inputs
553 * @return zero on successful negotiation
554 */
555 int avfilter_config_links(AVFilterContext *filter);
556
557 /**
558 * Request a picture buffer with a specific set of permissions.
559 * @param link the output link to the filter from which the picture will
560 * be requested
561 * @param perms the required access permissions
562 * @param w the minimum width of the buffer to allocate
563 * @param h the minimum height of the buffer to allocate
564 * @return A reference to the picture. This must be unreferenced with
565 * avfilter_unref_pic when you are finished with it.
566 */
567 AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms,
568 int w, int h);
569
570 /**
571 * Request an input frame from the filter at the other end of the link.
572 * @param link the input link
573 * @return zero on success
574 */
575 int avfilter_request_frame(AVFilterLink *link);
576
577 /**
578 * Poll a frame from the filter chain.
579 * @param link the input link
580 * @return the number of immediately available frames, a negative
581 * number in case of error
582 */
583 int avfilter_poll_frame(AVFilterLink *link);
584
585 /**
586 * Notifie the next filter of the start of a frame.
587 * @param link the output link the frame will be sent over
588 * @param picref A reference to the frame about to be sent. The data for this
589 * frame need only be valid once draw_slice() is called for that
590 * portion. The receiving filter will free this reference when
591 * it no longer needs it.
592 */
593 void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
594
595 /**
596 * Notifie the next filter that the current frame has finished.
597 * @param link the output link the frame was sent over
598 */
599 void avfilter_end_frame(AVFilterLink *link);
600
601 /**
602 * Send a slice to the next filter.
603 *
604 * Slices have to be provided in sequential order, either in
605 * top-bottom or bottom-top order. If slices are provided in
606 * non-sequential order the behavior of the function is undefined.
607 *
608 * @param link the output link over which the frame is being sent
609 * @param y offset in pixels from the top of the image for this slice
610 * @param h height of this slice in pixels
611 * @param slice_dir the assumed direction for sending slices,
612 * from the top slice to the bottom slice if the value is 1,
613 * from the bottom slice to the top slice if the value is -1,
614 * for other values the behavior of the function is undefined.
615 */
616 void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
617
618 /** Initialize the filter system. Register all builtin filters. */
619 void avfilter_register_all(void);
620
621 /** Uninitialize the filter system. Unregister all filters. */
622 void avfilter_uninit(void);
623
624 /**
625 * Register a filter. This is only needed if you plan to use
626 * avfilter_get_by_name later to lookup the AVFilter structure by name. A
627 * filter can still by instantiated with avfilter_open even if it is not
628 * registered.
629 * @param filter the filter to register
630 * @return 0 if the registration was succesfull, a negative value
631 * otherwise
632 */
633 int avfilter_register(AVFilter *filter);
634
635 /**
636 * Get a filter definition matching the given name.
637 * @param name the filter name to find
638 * @return the filter definition, if any matching one is registered.
639 * NULL if none found.
640 */
641 AVFilter *avfilter_get_by_name(const char *name);
642
643 /**
644 * If filter is NULL, returns a pointer to the first registered filter pointer,
645 * if filter is non-NULL, returns the next pointer after filter.
646 * If the returned pointer points to NULL, the last registered filter
647 * was already reached.
648 */
649 AVFilter **av_filter_next(AVFilter **filter);
650
651 /**
652 * Create a filter instance.
653 * @param filter the filter to create an instance of
654 * @param inst_name Name to give to the new instance. Can be NULL for none.
655 * @return Pointer to the new instance on success. NULL on failure.
656 */
657 AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name);
658
659 /**
660 * Initialize a filter.
661 * @param filter the filter to initialize
662 * @param args A string of parameters to use when initializing the filter.
663 * The format and meaning of this string varies by filter.
664 * @param opaque Any extra non-string data needed by the filter. The meaning
665 * of this parameter varies by filter.
666 * @return zero on success
667 */
668 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
669
670 /**
671 * Destroy a filter.
672 * @param filter the filter to destroy
673 */
674 void avfilter_destroy(AVFilterContext *filter);
675
676 /**
677 * Insert a filter in the middle of an existing link.
678 * @param link the link into which the filter should be inserted
679 * @param filt the filter to be inserted
680 * @param in the input pad on the filter to connect
681 * @param out the output pad on the filter to connect
682 * @return zero on success
683 */
684 int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
685 unsigned in, unsigned out);
686
687 /**
688 * Insert a new pad.
689 * @param idx Insertion point. Pad is inserted at the end if this point
690 * is beyond the end of the list of pads.
691 * @param count Pointer to the number of pads in the list
692 * @param padidx_off Offset within an AVFilterLink structure to the element
693 * to increment when inserting a new pad causes link
694 * numbering to change
695 * @param pads Pointer to the pointer to the beginning of the list of pads
696 * @param links Pointer to the pointer to the beginning of the list of links
697 * @param newpad The new pad to add. A copy is made when adding.
698 */
699 void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
700 AVFilterPad **pads, AVFilterLink ***links,
701 AVFilterPad *newpad);
702
703 /** Insert a new input pad for the filter. */
704 static inline void avfilter_insert_inpad(AVFilterContext *f, unsigned index,
705 AVFilterPad *p)
706 {
707 avfilter_insert_pad(index, &f->input_count, offsetof(AVFilterLink, dstpad),
708 &f->input_pads, &f->inputs, p);
709 }
710
711 /** Insert a new output pad for the filter. */
712 static inline void avfilter_insert_outpad(AVFilterContext *f, unsigned index,
713 AVFilterPad *p)
714 {
715 avfilter_insert_pad(index, &f->output_count, offsetof(AVFilterLink, srcpad),
716 &f->output_pads, &f->outputs, p);
717 }
718
719 #endif /* AVFILTER_AVFILTER_H */