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[libav.git] / libavfilter / avfilter.h
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a5cbb2f4 1/*
664f6595 2 * filter layer
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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
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22#ifndef AVFILTER_AVFILTER_H
23#define AVFILTER_AVFILTER_H
a5cbb2f4 24
be19d752 25#define LIBAVFILTER_VERSION_MAJOR 0
b6fec3eb 26#define LIBAVFILTER_VERSION_MINOR 5
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27#define LIBAVFILTER_VERSION_MICRO 0
28
29#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
30 LIBAVFILTER_VERSION_MINOR, \
31 LIBAVFILTER_VERSION_MICRO)
32#define LIBAVFILTER_VERSION AV_VERSION(LIBAVFILTER_VERSION_MAJOR, \
33 LIBAVFILTER_VERSION_MINOR, \
34 LIBAVFILTER_VERSION_MICRO)
35#define LIBAVFILTER_BUILD LIBAVFILTER_VERSION_INT
a7d46657 36
a9c81431 37#include <stddef.h>
245976da 38#include "libavcodec/avcodec.h"
a5cbb2f4 39
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40/**
41 * Returns the LIBAVFILTER_VERSION_INT constant.
42 */
43unsigned avfilter_version(void);
44
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45typedef struct AVFilterContext AVFilterContext;
46typedef struct AVFilterLink AVFilterLink;
47typedef struct AVFilterPad AVFilterPad;
48
49/* TODO: look for other flags which may be useful in this structure (interlace
50 * flags, etc)
51 */
52/**
53 * A reference-counted picture data type used by the filter system. Filters
54 * should not store pointers to this structure directly, but instead use the
664f6595 55 * AVFilterPicRef structure below.
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56 */
57typedef struct AVFilterPic
58{
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59 uint8_t *data[4]; ///< picture data for each plane
60 int linesize[4]; ///< number of bytes per line
61 enum PixelFormat format; ///< colorspace
a5cbb2f4 62
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63 unsigned refcount; ///< number of references to this image
64
65 /** private data to be used by a custom free function */
a5cbb2f4 66 void *priv;
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67 /**
68 * A pointer to the function to deallocate this image if the default
69 * function is not sufficient. This could, for example, add the memory
70 * back into a memory pool to be reused later without the overhead of
71 * reallocating it from scratch.
72 */
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73 void (*free)(struct AVFilterPic *pic);
74} AVFilterPic;
75
76/**
77 * A reference to an AVFilterPic. Since filters can manipulate the origin of
78 * a picture to, for example, crop image without any memcpy, the picture origin
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79 * and dimensions are per-reference properties. Linesize is also useful for
80 * image flipping, frame to field filters, etc, and so is also per-reference.
a5cbb2f4 81 *
1a18860a 82 * TODO: add anything necessary for frame reordering
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83 */
84typedef struct AVFilterPicRef
85{
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86 AVFilterPic *pic; ///< the picture that this is a reference to
87 uint8_t *data[4]; ///< picture data for each plane
88 int linesize[4]; ///< number of bytes per line
89 int w; ///< image width
90 int h; ///< image height
a5cbb2f4 91
056f0431 92 int64_t pts; ///< presentation timestamp in units of 1/AV_TIME_BASE
1a18860a 93
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94 AVRational pixel_aspect; ///< pixel aspect ratio
95
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96 int perms; ///< permissions
97#define AV_PERM_READ 0x01 ///< can read from the buffer
98#define AV_PERM_WRITE 0x02 ///< can write to the buffer
99#define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer
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100#define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time
101#define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time
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102} AVFilterPicRef;
103
104/**
c5c6f626 105 * Adds a new reference to a picture.
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106 * @param ref an existing reference to the picture
107 * @param pmask a bitmask containing the allowable permissions in the new
13ff8fd0 108 * reference
664f6595 109 * @return a new reference to the picture with the same properties as the
13ff8fd0 110 * old, excluding any permissions denied by pmask
a5cbb2f4 111 */
16415eaf 112AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask);
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113
114/**
c5c6f626 115 * Removes a reference to a picture. If this is the last reference to the
a5cbb2f4 116 * picture, the picture itself is also automatically freed.
664f6595 117 * @param ref reference to the picture
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118 */
119void avfilter_unref_pic(AVFilterPicRef *ref);
120
13ff8fd0 121/**
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122 * A list of supported formats for one end of a filter link. This is used
123 * during the format negotiation process to try to pick the best format to
124 * use to minimize the number of necessary conversions. Each filter gives a
125 * list of the formats supported by each input and output pad. The list
126 * given for each pad need not be distinct - they may be references to the
127 * same list of formats, as is often the case when a filter supports multiple
42f72a3a 128 * formats, but will always output the same format as it is given in input.
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129 *
130 * In this way, a list of possible input formats and a list of possible
131 * output formats are associated with each link. When a set of formats is
132 * negotiated over a link, the input and output lists are merged to form a
133 * new list containing only the common elements of each list. In the case
134 * that there were no common elements, a format conversion is necessary.
135 * Otherwise, the lists are merged, and all other links which reference
136 * either of the format lists involved in the merge are also affected.
137 *
138 * For example, consider the filter chain:
139 * filter (a) --> (b) filter (b) --> (c) filter
140 *
141 * where the letters in parenthesis indicate a list of formats supported on
142 * the input or output of the link. Suppose the lists are as follows:
143 * (a) = {A, B}
144 * (b) = {A, B, C}
145 * (c) = {B, C}
146 *
147 * First, the first link's lists are merged, yielding:
148 * filter (a) --> (a) filter (a) --> (c) filter
149 *
150 * Notice that format list (b) now refers to the same list as filter list (a).
151 * Next, the lists for the second link are merged, yielding:
152 * filter (a) --> (a) filter (a) --> (a) filter
153 *
154 * where (a) = {B}.
155 *
156 * Unfortunately, when the format lists at the two ends of a link are merged,
157 * we must ensure that all links which reference either pre-merge format list
158 * get updated as well. Therefore, we have the format list structure store a
159 * pointer to each of the pointers to itself.
160 */
161typedef struct AVFilterFormats AVFilterFormats;
162struct AVFilterFormats
163{
164 unsigned format_count; ///< number of formats
165 int *formats; ///< list of formats
166
167 unsigned refcount; ///< number of references to this list
168 AVFilterFormats ***refs; ///< references to this list
169};
170
171/**
172 * Helper function to create a list of supported formats. This is intended
173 * for use in AVFilter->query_formats().
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174 * @param len the number of formats supported
175 * @param ... a list of the supported formats
176 * @return the format list, with no existing references
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177 */
178AVFilterFormats *avfilter_make_format_list(int len, ...);
179
180/**
853961a9 181 * Returns a list of all colorspaces supported by FFmpeg.
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182 */
183AVFilterFormats *avfilter_all_colorspaces(void);
184
185/**
33a0facf 186 * Returns a format list which contains the intersection of the formats of
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187 * a and b. Also, all the references of a, all the references of b, and
188 * a and b themselves will be deallocated.
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189 *
190 * If a and b do not share any common formats, neither is modified, and NULL
191 * is returned.
192 */
193AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b);
194
09b63a42 195/**
a27c8d5f 196 * Adds *ref as a new reference to formats.
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197 * That is the pointers will point like in the ascii art below:
198 * ________
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199 * |formats |<--------.
200 * | ____ | ____|___________________
201 * | |refs| | | __|_
202 * | |* * | | | | | | AVFilterLink
09b63a42 203 * | |* *--------->|*ref|
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204 * | |____| | | |____|
205 * |________| |________________________
09b63a42 206 */
a27c8d5f 207void avfilter_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref);
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208
209/**
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210 * Removes *ref as a reference to the format list it currently points to,
211 * deallocates that list if this was the last reference, and sets *ref to NULL.
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212 *
213 * Before After
214 * ________ ________ NULL
215 * |formats |<--------. |formats | ^
216 * | ____ | ____|________________ | ____ | ____|________________
217 * | |refs| | | __|_ | |refs| | | __|_
218 * | |* * | | | | | | AVFilterLink | |* * | | | | | | AVFilterLink
219 * | |* *--------->|*ref| | |* | | | |*ref|
220 * | |____| | | |____| | |____| | | |____|
221 * |________| |_____________________ |________| |_____________________
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222 */
223void avfilter_formats_unref(AVFilterFormats **ref);
224
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225/**
226 *
227 * Before After
228 * ________ ________
a27c8d5f 229 * |formats |<---------. |formats |<---------.
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230 * | ____ | ___|___ | ____ | ___|___
231 * | |refs| | | | | | |refs| | | | | NULL
232 * | |* *--------->|*oldref| | |* *--------->|*newref| ^
233 * | |* * | | |_______| | |* * | | |_______| ___|___
234 * | |____| | | |____| | | | |
235 * |________| |________| |*oldref|
236 * |_______|
237 */
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238void avfilter_formats_changeref(AVFilterFormats **oldref,
239 AVFilterFormats **newref);
240
35f3fdf4 241/**
664f6595 242 * A filter pad used for either input or output.
13ff8fd0 243 */
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244struct AVFilterPad
245{
246 /**
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247 * Pad name. The name is unique among inputs and among outputs, but an
248 * input may have the same name as an output. This may be NULL if this
249 * pad has no need to ever be referenced by name.
a5cbb2f4 250 */
2844dd39 251 const char *name;
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252
253 /**
254 * AVFilterPad type. Only video supported now, hopefully someone will
255 * add audio in the future.
256 */
daafdb6e 257 enum CodecType type;
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258
259 /**
91535e5f 260 * Minimum required permissions on incoming buffers. Any buffer with
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261 * insufficient permissions will be automatically copied by the filter
262 * system to a new buffer which provides the needed access permissions.
263 *
264 * Input pads only.
265 */
266 int min_perms;
267
268 /**
269 * Permissions which are not accepted on incoming buffers. Any buffer
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270 * which has any of these permissions set will be automatically copied
271 * by the filter system to a new buffer which does not have those
272 * permissions. This can be used to easily disallow buffers with
273 * AV_PERM_REUSE.
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274 *
275 * Input pads only.
276 */
277 int rej_perms;
278
279 /**
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280 * Callback called before passing the first slice of a new frame. If
281 * NULL, the filter layer will default to storing a reference to the
282 * picture inside the link structure.
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283 *
284 * Input video pads only.
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285 */
286 void (*start_frame)(AVFilterLink *link, AVFilterPicRef *picref);
287
288 /**
289 * Callback function to get a buffer. If NULL, the filter system will
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290 * handle buffer requests.
291 *
292 * Input video pads only.
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293 */
294 AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms);
295
296 /**
297 * Callback called after the slices of a frame are completely sent. If
298 * NULL, the filter layer will default to releasing the reference stored
299 * in the link structure during start_frame().
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300 *
301 * Input video pads only.
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302 */
303 void (*end_frame)(AVFilterLink *link);
304
305 /**
306 * Slice drawing callback. This is where a filter receives video data
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307 * and should do its processing.
308 *
309 * Input video pads only.
a5cbb2f4 310 */
72f6d631 311 void (*draw_slice)(AVFilterLink *link, int y, int height);
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312
313 /**
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314 * Frame poll callback. This returns the number of immediately available
315 * frames. It should return a positive value if the next request_frame()
316 * is guaranteed to return one frame (with no delay).
317 *
318 * Defaults to just calling the source poll_frame() method.
319 *
320 * Output video pads only.
321 */
322 int (*poll_frame)(AVFilterLink *link);
323
324 /**
a5cbb2f4 325 * Frame request callback. A call to this should result in at least one
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326 * frame being output over the given link. This should return zero on
327 * success, and another value on error.
328 *
329 * Output video pads only.
a5cbb2f4 330 */
63f64e6f 331 int (*request_frame)(AVFilterLink *link);
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332
333 /**
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334 * Link configuration callback.
335 *
336 * For output pads, this should set the link properties such as
337 * width/height. This should NOT set the format property - that is
338 * negotiated between filters by the filter system using the
339 * query_formats() callback before this function is called.
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340 *
341 * For input pads, this should check the properties of the link, and update
342 * the filter's internal state as necessary.
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343 *
344 * For both input and output filters, this should return zero on success,
345 * and another value on error.
a5cbb2f4 346 */
d3e57c15 347 int (*config_props)(AVFilterLink *link);
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348};
349
2b187df9 350/** default handler for start_frame() for video inputs */
a5cbb2f4 351void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
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352/** default handler for draw_slice() for video inputs */
353void avfilter_default_draw_slice(AVFilterLink *link, int y, int h);
2b187df9 354/** default handler for end_frame() for video inputs */
a5cbb2f4 355void avfilter_default_end_frame(AVFilterLink *link);
2b187df9 356/** default handler for config_props() for video outputs */
901e6b39 357int avfilter_default_config_output_link(AVFilterLink *link);
2b187df9 358/** default handler for config_props() for video inputs */
85322466 359int avfilter_default_config_input_link (AVFilterLink *link);
2b187df9 360/** default handler for get_video_buffer() for video inputs */
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361AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link,
362 int perms);
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363/**
364 * A helper for query_formats() which sets all links to the same list of
365 * formats. If there are no links hooked to this filter, the list of formats is
366 * freed.
367 */
368void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats);
369/** Default handler for query_formats() */
370int avfilter_default_query_formats(AVFilterContext *ctx);
a5cbb2f4 371
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372/**
373 * Filter definition. This defines the pads a filter contains, and all the
374 * callback functions used to interact with the filter.
375 */
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376typedef struct
377{
2844dd39 378 const char *name; ///< filter name
a5cbb2f4 379
13ff8fd0 380 int priv_size; ///< size of private data to allocate for the filter
a5cbb2f4 381
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382 /**
383 * Filter initialization function. Args contains the user-supplied
384 * parameters. FIXME: maybe an AVOption-based system would be better?
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385 * opaque is data provided by the code requesting creation of the filter,
386 * and is used to pass data to the filter.
4d96a914 387 */
95bcf498 388 int (*init)(AVFilterContext *ctx, const char *args, void *opaque);
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389
390 /**
391 * Filter uninitialization function. Should deallocate any memory held
392 * by the filter, release any picture references, etc. This does not need
393 * to deallocate the AVFilterContext->priv memory itself.
394 */
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395 void (*uninit)(AVFilterContext *ctx);
396
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397 /**
398 * Query formats supported by the filter and its pads. Should set the
399 * in_formats for links connected to its output pads, and out_formats
400 * for links connected to its input pads.
401 *
402 * Should return zero on success.
403 */
404 int (*query_formats)(AVFilterContext *);
405
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406 const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none
407 const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none
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408} AVFilter;
409
13ff8fd0 410/** An instance of a filter */
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411struct AVFilterContext
412{
d42a814e 413 const AVClass *av_class; ///< needed for av_log()
a5cbb2f4 414
664f6595 415 AVFilter *filter; ///< the AVFilter of which this is an instance
a5cbb2f4 416
13ff8fd0 417 char *name; ///< name of this filter instance
dcea2482 418
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419 unsigned input_count; ///< number of input pads
420 AVFilterPad *input_pads; ///< array of input pads
421 AVFilterLink **inputs; ///< array of pointers to input links
25f8e601 422
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423 unsigned output_count; ///< number of output pads
424 AVFilterPad *output_pads; ///< array of output pads
425 AVFilterLink **outputs; ///< array of pointers to output links
a5cbb2f4 426
13ff8fd0 427 void *priv; ///< private data for use by the filter
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428};
429
13ff8fd0 430/**
664f6595 431 * A link between two filters. This contains pointers to the source and
f4433de9 432 * destination filters between which this link exists, and the indexes of
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433 * the pads involved. In addition, this link also contains the parameters
434 * which have been negotiated and agreed upon between the filter, such as
2b187df9 435 * image dimensions, format, etc.
13ff8fd0 436 */
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437struct AVFilterLink
438{
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439 AVFilterContext *src; ///< source filter
440 unsigned int srcpad; ///< index of the output pad on the source filter
a5cbb2f4 441
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442 AVFilterContext *dst; ///< dest filter
443 unsigned int dstpad; ///< index of the input pad on the dest filter
a5cbb2f4 444
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445 /** stage of the initialization of the link properties (dimensions, etc) */
446 enum {
447 AVLINK_UNINIT = 0, ///< not started
448 AVLINK_STARTINIT, ///< started, but incomplete
449 AVLINK_INIT ///< complete
450 } init_state;
451
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452 int w; ///< agreed upon image width
453 int h; ///< agreed upon image height
454 enum PixelFormat format; ///< agreed upon image colorspace
a5cbb2f4 455
60bf6ce3 456 /**
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457 * Lists of formats supported by the input and output filters respectively.
458 * These lists are used for negotiating the format to actually be used,
459 * which will be loaded into the format member, above, when chosen.
460 */
461 AVFilterFormats *in_formats;
462 AVFilterFormats *out_formats;
463
464 /**
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465 * The picture reference currently being sent across the link by the source
466 * filter. This is used internally by the filter system to allow
664f6595 467 * automatic copying of pictures which do not have sufficient permissions
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468 * for the destination. This should not be accessed directly by the
469 * filters.
470 */
471 AVFilterPicRef *srcpic;
472
a5cbb2f4 473 AVFilterPicRef *cur_pic;
462f57db 474 AVFilterPicRef *outpic;
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475};
476
13ff8fd0 477/**
c5c6f626 478 * Links two filters together.
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479 * @param src the source filter
480 * @param srcpad index of the output pad on the source filter
481 * @param dst the destination filter
482 * @param dstpad index of the input pad on the destination filter
483 * @return zero on success
13ff8fd0 484 */
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485int avfilter_link(AVFilterContext *src, unsigned srcpad,
486 AVFilterContext *dst, unsigned dstpad);
487
13ff8fd0 488/**
c5c6f626 489 * Negotiates the colorspace, dimensions, etc of all inputs to a filter.
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490 * @param filter the filter to negotiate the properties for its inputs
491 * @return zero on successful negotiation
13ff8fd0 492 */
24c4eff6 493int avfilter_config_links(AVFilterContext *filter);
85322466 494
13ff8fd0 495/**
c5c6f626 496 * Requests a picture buffer with a specific set of permissions.
664f6595 497 * @param link the output link to the filter from which the picture will
13ff8fd0 498 * be requested
664f6595 499 * @param perms the required access permissions
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500 * @return A reference to the picture. This must be unreferenced with
501 * avfilter_unref_pic when you are finished with it.
502 */
a5cbb2f4 503AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms);
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504
505/**
c5c6f626 506 * Requests an input frame from the filter at the other end of the link.
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507 * @param link the input link
508 * @return zero on success
13ff8fd0 509 */
0155b1a1 510int avfilter_request_frame(AVFilterLink *link);
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511
512/**
c5c6f626 513 * Polls a frame from the filter chain.
b04c740a 514 * @param link the input link
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515 * @return the number of immediately available frames, a negative
516 * number in case of error
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517 */
518int avfilter_poll_frame(AVFilterLink *link);
519
520/**
c5c6f626 521 * Notifies the next filter of the start of a frame.
664f6595 522 * @param link the output link the frame will be sent over
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523 * @param picref A reference to the frame about to be sent. The data for this
524 * frame need only be valid once draw_slice() is called for that
525 * portion. The receiving filter will free this reference when
526 * it no longer needs it.
527 */
a5cbb2f4 528void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
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529
530/**
c5c6f626 531 * Notifies the next filter that the current frame has finished.
664f6595 532 * @param link the output link the frame was sent over
13ff8fd0 533 */
a5cbb2f4 534void avfilter_end_frame(AVFilterLink *link);
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535
536/**
c5c6f626 537 * Sends a slice to the next filter.
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538 * @param link the output link over which the frame is being sent
539 * @param y offset in pixels from the top of the image for this slice
540 * @param h height of this slice in pixels
13ff8fd0 541 */
72f6d631 542void avfilter_draw_slice(AVFilterLink *link, int y, int h);
a5cbb2f4 543
13ff8fd0 544/** Initialize the filter system. Registers all builtin filters */
11de6cac 545void avfilter_register_all(void);
e4152452 546
13ff8fd0 547/** Uninitialize the filter system. Unregisters all filters */
a5cbb2f4 548void avfilter_uninit(void);
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549
550/**
c5c6f626 551 * Registers a filter. This is only needed if you plan to use
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552 * avfilter_get_by_name later to lookup the AVFilter structure by name. A
553 * filter can still by instantiated with avfilter_open even if it is not
554 * registered.
664f6595 555 * @param filter the filter to register
13ff8fd0 556 */
a5cbb2f4 557void avfilter_register(AVFilter *filter);
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558
559/**
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560 * Gets a filter definition matching the given name.
561 * @param name the filter name to find
562 * @return the filter definition, if any matching one is registered.
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563 * NULL if none found.
564 */
2844dd39 565AVFilter *avfilter_get_by_name(const char *name);
a5cbb2f4 566
13ff8fd0 567/**
c5c6f626 568 * Creates a filter instance.
664f6595 569 * @param filter the filter to create an instance of
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570 * @param inst_name Name to give to the new instance. Can be NULL for none.
571 * @return Pointer to the new instance on success. NULL on failure.
572 */
2844dd39 573AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name);
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574
575/**
c5c6f626 576 * Initializes a filter.
664f6595 577 * @param filter the filter to initialize
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578 * @param args A string of parameters to use when initializing the filter.
579 * The format and meaning of this string varies by filter.
580 * @param opaque Any extra non-string data needed by the filter. The meaning
581 * of this parameter varies by filter.
664f6595 582 * @return zero on success
13ff8fd0 583 */
6e365c57 584int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
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585
586/**
c5c6f626 587 * Destroys a filter.
664f6595 588 * @param filter the filter to destroy
13ff8fd0 589 */
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590void avfilter_destroy(AVFilterContext *filter);
591
13ff8fd0 592/**
c5c6f626 593 * Inserts a filter in the middle of an existing link.
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594 * @param link the link into which the filter should be inserted
595 * @param filt the filter to be inserted
596 * @param in the input pad on the filter to connect
597 * @param out the output pad on the filter to connect
598 * @return zero on success
13ff8fd0 599 */
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600int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
601 unsigned in, unsigned out);
d3e57c15 602
a9c81431 603/**
c5c6f626 604 * Inserts a new pad.
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605 * @param idx Insertion point. Pad is inserted at the end if this point
606 * is beyond the end of the list of pads.
607 * @param count Pointer to the number of pads in the list
608 * @param padidx_off Offset within an AVFilterLink structure to the element
609 * to increment when inserting a new pad causes link
610 * numbering to change
611 * @param pads Pointer to the pointer to the beginning of the list of pads
612 * @param links Pointer to the pointer to the beginning of the list of links
613 * @param newpad The new pad to add. A copy is made when adding.
614 */
615void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
616 AVFilterPad **pads, AVFilterLink ***links,
617 AVFilterPad *newpad);
618
c5c6f626 619/** Inserts a new input pad for the filter. */
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620static inline void avfilter_insert_inpad(AVFilterContext *f, unsigned index,
621 AVFilterPad *p)
622{
623 avfilter_insert_pad(index, &f->input_count, offsetof(AVFilterLink, dstpad),
624 &f->input_pads, &f->inputs, p);
625}
626
c5c6f626 627/** Inserts a new output pad for the filter. */
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628static inline void avfilter_insert_outpad(AVFilterContext *f, unsigned index,
629 AVFilterPad *p)
630{
631 avfilter_insert_pad(index, &f->output_count, offsetof(AVFilterLink, srcpad),
632 &f->output_pads, &f->outputs, p);
633}
634
98790382 635#endif /* AVFILTER_AVFILTER_H */