You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

1042 lines
36KB

  1. /*
  2. * filter layer
  3. * Copyright (c) 2007 Bobby Bingham
  4. *
  5. * This file is part of Libav.
  6. *
  7. * Libav 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. * Libav 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 Libav; if not, write to the Free Software
  19. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20. */
  21. #ifndef AVFILTER_AVFILTER_H
  22. #define AVFILTER_AVFILTER_H
  23. /**
  24. * @file
  25. * @ingroup lavfi
  26. * Main libavfilter public API header
  27. */
  28. /**
  29. * @defgroup lavfi Libavfilter - graph-based frame editing library
  30. * @{
  31. */
  32. #include "libavutil/avutil.h"
  33. #include "libavutil/frame.h"
  34. #include "libavutil/log.h"
  35. #include "libavutil/samplefmt.h"
  36. #include "libavutil/pixfmt.h"
  37. #include "libavutil/rational.h"
  38. #include "libavcodec/avcodec.h"
  39. #include <stddef.h>
  40. #include "libavfilter/version.h"
  41. /**
  42. * Return the LIBAVFILTER_VERSION_INT constant.
  43. */
  44. unsigned avfilter_version(void);
  45. /**
  46. * Return the libavfilter build-time configuration.
  47. */
  48. const char *avfilter_configuration(void);
  49. /**
  50. * Return the libavfilter license.
  51. */
  52. const char *avfilter_license(void);
  53. typedef struct AVFilterContext AVFilterContext;
  54. typedef struct AVFilterLink AVFilterLink;
  55. typedef struct AVFilterPad AVFilterPad;
  56. typedef struct AVFilterFormats AVFilterFormats;
  57. #if FF_API_AVFILTERBUFFER
  58. /**
  59. * A reference-counted buffer data type used by the filter system. Filters
  60. * should not store pointers to this structure directly, but instead use the
  61. * AVFilterBufferRef structure below.
  62. */
  63. typedef struct AVFilterBuffer {
  64. uint8_t *data[8]; ///< buffer data for each plane/channel
  65. /**
  66. * pointers to the data planes/channels.
  67. *
  68. * For video, this should simply point to data[].
  69. *
  70. * For planar audio, each channel has a separate data pointer, and
  71. * linesize[0] contains the size of each channel buffer.
  72. * For packed audio, there is just one data pointer, and linesize[0]
  73. * contains the total size of the buffer for all channels.
  74. *
  75. * Note: Both data and extended_data will always be set, but for planar
  76. * audio with more channels that can fit in data, extended_data must be used
  77. * in order to access all channels.
  78. */
  79. uint8_t **extended_data;
  80. int linesize[8]; ///< number of bytes per line
  81. /** private data to be used by a custom free function */
  82. void *priv;
  83. /**
  84. * A pointer to the function to deallocate this buffer if the default
  85. * function is not sufficient. This could, for example, add the memory
  86. * back into a memory pool to be reused later without the overhead of
  87. * reallocating it from scratch.
  88. */
  89. void (*free)(struct AVFilterBuffer *buf);
  90. int format; ///< media format
  91. int w, h; ///< width and height of the allocated buffer
  92. unsigned refcount; ///< number of references to this buffer
  93. } AVFilterBuffer;
  94. #define AV_PERM_READ 0x01 ///< can read from the buffer
  95. #define AV_PERM_WRITE 0x02 ///< can write to the buffer
  96. #define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer
  97. #define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time
  98. #define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time
  99. #define AV_PERM_NEG_LINESIZES 0x20 ///< the buffer requested can have negative linesizes
  100. /**
  101. * Audio specific properties in a reference to an AVFilterBuffer. Since
  102. * AVFilterBufferRef is common to different media formats, audio specific
  103. * per reference properties must be separated out.
  104. */
  105. typedef struct AVFilterBufferRefAudioProps {
  106. uint64_t channel_layout; ///< channel layout of audio buffer
  107. int nb_samples; ///< number of audio samples
  108. int sample_rate; ///< audio buffer sample rate
  109. int planar; ///< audio buffer - planar or packed
  110. } AVFilterBufferRefAudioProps;
  111. /**
  112. * Video specific properties in a reference to an AVFilterBuffer. Since
  113. * AVFilterBufferRef is common to different media formats, video specific
  114. * per reference properties must be separated out.
  115. */
  116. typedef struct AVFilterBufferRefVideoProps {
  117. int w; ///< image width
  118. int h; ///< image height
  119. AVRational pixel_aspect; ///< pixel aspect ratio
  120. int interlaced; ///< is frame interlaced
  121. int top_field_first; ///< field order
  122. enum AVPictureType pict_type; ///< picture type of the frame
  123. int key_frame; ///< 1 -> keyframe, 0-> not
  124. } AVFilterBufferRefVideoProps;
  125. /**
  126. * A reference to an AVFilterBuffer. Since filters can manipulate the origin of
  127. * a buffer to, for example, crop image without any memcpy, the buffer origin
  128. * and dimensions are per-reference properties. Linesize is also useful for
  129. * image flipping, frame to field filters, etc, and so is also per-reference.
  130. *
  131. * TODO: add anything necessary for frame reordering
  132. */
  133. typedef struct AVFilterBufferRef {
  134. AVFilterBuffer *buf; ///< the buffer that this is a reference to
  135. uint8_t *data[8]; ///< picture/audio data for each plane
  136. /**
  137. * pointers to the data planes/channels.
  138. *
  139. * For video, this should simply point to data[].
  140. *
  141. * For planar audio, each channel has a separate data pointer, and
  142. * linesize[0] contains the size of each channel buffer.
  143. * For packed audio, there is just one data pointer, and linesize[0]
  144. * contains the total size of the buffer for all channels.
  145. *
  146. * Note: Both data and extended_data will always be set, but for planar
  147. * audio with more channels that can fit in data, extended_data must be used
  148. * in order to access all channels.
  149. */
  150. uint8_t **extended_data;
  151. int linesize[8]; ///< number of bytes per line
  152. AVFilterBufferRefVideoProps *video; ///< video buffer specific properties
  153. AVFilterBufferRefAudioProps *audio; ///< audio buffer specific properties
  154. /**
  155. * presentation timestamp. The time unit may change during
  156. * filtering, as it is specified in the link and the filter code
  157. * may need to rescale the PTS accordingly.
  158. */
  159. int64_t pts;
  160. int64_t pos; ///< byte position in stream, -1 if unknown
  161. int format; ///< media format
  162. int perms; ///< permissions, see the AV_PERM_* flags
  163. enum AVMediaType type; ///< media type of buffer data
  164. } AVFilterBufferRef;
  165. /**
  166. * Copy properties of src to dst, without copying the actual data
  167. */
  168. attribute_deprecated
  169. void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, AVFilterBufferRef *src);
  170. /**
  171. * Add a new reference to a buffer.
  172. *
  173. * @param ref an existing reference to the buffer
  174. * @param pmask a bitmask containing the allowable permissions in the new
  175. * reference
  176. * @return a new reference to the buffer with the same properties as the
  177. * old, excluding any permissions denied by pmask
  178. */
  179. attribute_deprecated
  180. AVFilterBufferRef *avfilter_ref_buffer(AVFilterBufferRef *ref, int pmask);
  181. /**
  182. * Remove a reference to a buffer. If this is the last reference to the
  183. * buffer, the buffer itself is also automatically freed.
  184. *
  185. * @param ref reference to the buffer, may be NULL
  186. *
  187. * @note it is recommended to use avfilter_unref_bufferp() instead of this
  188. * function
  189. */
  190. attribute_deprecated
  191. void avfilter_unref_buffer(AVFilterBufferRef *ref);
  192. /**
  193. * Remove a reference to a buffer and set the pointer to NULL.
  194. * If this is the last reference to the buffer, the buffer itself
  195. * is also automatically freed.
  196. *
  197. * @param ref pointer to the buffer reference
  198. */
  199. attribute_deprecated
  200. void avfilter_unref_bufferp(AVFilterBufferRef **ref);
  201. #endif
  202. #if FF_API_AVFILTERPAD_PUBLIC
  203. /**
  204. * A filter pad used for either input or output.
  205. *
  206. * @warning this struct will be removed from public API.
  207. * users should call avfilter_pad_get_name() and avfilter_pad_get_type()
  208. * to access the name and type fields; there should be no need to access
  209. * any other fields from outside of libavfilter.
  210. */
  211. struct AVFilterPad {
  212. /**
  213. * Pad name. The name is unique among inputs and among outputs, but an
  214. * input may have the same name as an output. This may be NULL if this
  215. * pad has no need to ever be referenced by name.
  216. */
  217. const char *name;
  218. /**
  219. * AVFilterPad type.
  220. */
  221. enum AVMediaType type;
  222. /**
  223. * Minimum required permissions on incoming buffers. Any buffer with
  224. * insufficient permissions will be automatically copied by the filter
  225. * system to a new buffer which provides the needed access permissions.
  226. *
  227. * Input pads only.
  228. */
  229. attribute_deprecated int min_perms;
  230. /**
  231. * Permissions which are not accepted on incoming buffers. Any buffer
  232. * which has any of these permissions set will be automatically copied
  233. * by the filter system to a new buffer which does not have those
  234. * permissions. This can be used to easily disallow buffers with
  235. * AV_PERM_REUSE.
  236. *
  237. * Input pads only.
  238. */
  239. attribute_deprecated int rej_perms;
  240. /**
  241. * @deprecated unused
  242. */
  243. int (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref);
  244. /**
  245. * Callback function to get a video buffer. If NULL, the filter system will
  246. * use avfilter_default_get_video_buffer().
  247. *
  248. * Input video pads only.
  249. */
  250. AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h);
  251. /**
  252. * Callback function to get an audio buffer. If NULL, the filter system will
  253. * use avfilter_default_get_audio_buffer().
  254. *
  255. * Input audio pads only.
  256. */
  257. AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples);
  258. /**
  259. * @deprecated unused
  260. */
  261. int (*end_frame)(AVFilterLink *link);
  262. /**
  263. * @deprecated unused
  264. */
  265. int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir);
  266. /**
  267. * Filtering callback. This is where a filter receives a frame with
  268. * audio/video data and should do its processing.
  269. *
  270. * Input pads only.
  271. *
  272. * @return >= 0 on success, a negative AVERROR on error. This function
  273. * must ensure that samplesref is properly unreferenced on error if it
  274. * hasn't been passed on to another filter.
  275. */
  276. int (*filter_frame)(AVFilterLink *link, AVFrame *frame);
  277. /**
  278. * Frame poll callback. This returns the number of immediately available
  279. * samples. It should return a positive value if the next request_frame()
  280. * is guaranteed to return one frame (with no delay).
  281. *
  282. * Defaults to just calling the source poll_frame() method.
  283. *
  284. * Output pads only.
  285. */
  286. int (*poll_frame)(AVFilterLink *link);
  287. /**
  288. * Frame request callback. A call to this should result in at least one
  289. * frame being output over the given link. This should return zero on
  290. * success, and another value on error.
  291. *
  292. * Output pads only.
  293. */
  294. int (*request_frame)(AVFilterLink *link);
  295. /**
  296. * Link configuration callback.
  297. *
  298. * For output pads, this should set the link properties such as
  299. * width/height. This should NOT set the format property - that is
  300. * negotiated between filters by the filter system using the
  301. * query_formats() callback before this function is called.
  302. *
  303. * For input pads, this should check the properties of the link, and update
  304. * the filter's internal state as necessary.
  305. *
  306. * For both input and output filters, this should return zero on success,
  307. * and another value on error.
  308. */
  309. int (*config_props)(AVFilterLink *link);
  310. /**
  311. * The filter expects a fifo to be inserted on its input link,
  312. * typically because it has a delay.
  313. *
  314. * input pads only.
  315. */
  316. int needs_fifo;
  317. int needs_writable;
  318. };
  319. #endif
  320. /**
  321. * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
  322. * AVFilter.inputs/outputs).
  323. */
  324. int avfilter_pad_count(const AVFilterPad *pads);
  325. /**
  326. * Get the name of an AVFilterPad.
  327. *
  328. * @param pads an array of AVFilterPads
  329. * @param pad_idx index of the pad in the array it; is the caller's
  330. * responsibility to ensure the index is valid
  331. *
  332. * @return name of the pad_idx'th pad in pads
  333. */
  334. const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx);
  335. /**
  336. * Get the type of an AVFilterPad.
  337. *
  338. * @param pads an array of AVFilterPads
  339. * @param pad_idx index of the pad in the array; it is the caller's
  340. * responsibility to ensure the index is valid
  341. *
  342. * @return type of the pad_idx'th pad in pads
  343. */
  344. enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);
  345. /**
  346. * The number of the filter inputs is not determined just by AVFilter.inputs.
  347. * The filter might add additional inputs during initialization depending on the
  348. * options supplied to it.
  349. */
  350. #define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0)
  351. /**
  352. * The number of the filter outputs is not determined just by AVFilter.outputs.
  353. * The filter might add additional outputs during initialization depending on
  354. * the options supplied to it.
  355. */
  356. #define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1)
  357. /**
  358. * The filter supports multithreading by splitting frames into multiple parts
  359. * and processing them concurrently.
  360. */
  361. #define AVFILTER_FLAG_SLICE_THREADS (1 << 2)
  362. /**
  363. * Filter definition. This defines the pads a filter contains, and all the
  364. * callback functions used to interact with the filter.
  365. */
  366. typedef struct AVFilter {
  367. const char *name; ///< filter name
  368. /**
  369. * A description for the filter. You should use the
  370. * NULL_IF_CONFIG_SMALL() macro to define it.
  371. */
  372. const char *description;
  373. const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none
  374. const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none
  375. /**
  376. * A class for the private data, used to access filter private
  377. * AVOptions.
  378. */
  379. const AVClass *priv_class;
  380. /**
  381. * A combination of AVFILTER_FLAG_*
  382. */
  383. int flags;
  384. /*****************************************************************
  385. * All fields below this line are not part of the public API. They
  386. * may not be used outside of libavfilter and can be changed and
  387. * removed at will.
  388. * New public fields should be added right above.
  389. *****************************************************************
  390. */
  391. /**
  392. * Filter initialization function. Called when all the options have been
  393. * set.
  394. */
  395. int (*init)(AVFilterContext *ctx);
  396. /**
  397. * Should be set instead of init by the filters that want to pass a
  398. * dictionary of AVOptions to nested contexts that are allocated in
  399. * init.
  400. */
  401. int (*init_dict)(AVFilterContext *ctx, AVDictionary **options);
  402. /**
  403. * Filter uninitialization function. Should deallocate any memory held
  404. * by the filter, release any buffer references, etc. This does not need
  405. * to deallocate the AVFilterContext->priv memory itself.
  406. */
  407. void (*uninit)(AVFilterContext *ctx);
  408. /**
  409. * Queries formats supported by the filter and its pads, and sets the
  410. * in_formats for links connected to its output pads, and out_formats
  411. * for links connected to its input pads.
  412. *
  413. * @return zero on success, a negative value corresponding to an
  414. * AVERROR code otherwise
  415. */
  416. int (*query_formats)(AVFilterContext *);
  417. int priv_size; ///< size of private data to allocate for the filter
  418. struct AVFilter *next;
  419. } AVFilter;
  420. /**
  421. * Process multiple parts of the frame concurrently.
  422. */
  423. #define AVFILTER_THREAD_SLICE (1 << 0)
  424. typedef struct AVFilterInternal AVFilterInternal;
  425. /** An instance of a filter */
  426. struct AVFilterContext {
  427. const AVClass *av_class; ///< needed for av_log()
  428. const AVFilter *filter; ///< the AVFilter of which this is an instance
  429. char *name; ///< name of this filter instance
  430. AVFilterPad *input_pads; ///< array of input pads
  431. AVFilterLink **inputs; ///< array of pointers to input links
  432. #if FF_API_FOO_COUNT
  433. unsigned input_count; ///< @deprecated use nb_inputs
  434. #endif
  435. unsigned nb_inputs; ///< number of input pads
  436. AVFilterPad *output_pads; ///< array of output pads
  437. AVFilterLink **outputs; ///< array of pointers to output links
  438. #if FF_API_FOO_COUNT
  439. unsigned output_count; ///< @deprecated use nb_outputs
  440. #endif
  441. unsigned nb_outputs; ///< number of output pads
  442. void *priv; ///< private data for use by the filter
  443. struct AVFilterGraph *graph; ///< filtergraph this filter belongs to
  444. /**
  445. * Type of multithreading being allowed/used. A combination of
  446. * AVFILTER_THREAD_* flags.
  447. *
  448. * May be set by the caller before initializing the filter to forbid some
  449. * or all kinds of multithreading for this filter. The default is allowing
  450. * everything.
  451. *
  452. * When the filter is initialized, this field is combined using bit AND with
  453. * AVFilterGraph.thread_type to get the final mask used for determining
  454. * allowed threading types. I.e. a threading type needs to be set in both
  455. * to be allowed.
  456. *
  457. * After the filter is initialzed, libavfilter sets this field to the
  458. * threading type that is actually used (0 for no multithreading).
  459. */
  460. int thread_type;
  461. /**
  462. * An opaque struct for libavfilter internal use.
  463. */
  464. AVFilterInternal *internal;
  465. };
  466. /**
  467. * A link between two filters. This contains pointers to the source and
  468. * destination filters between which this link exists, and the indexes of
  469. * the pads involved. In addition, this link also contains the parameters
  470. * which have been negotiated and agreed upon between the filter, such as
  471. * image dimensions, format, etc.
  472. */
  473. struct AVFilterLink {
  474. AVFilterContext *src; ///< source filter
  475. AVFilterPad *srcpad; ///< output pad on the source filter
  476. AVFilterContext *dst; ///< dest filter
  477. AVFilterPad *dstpad; ///< input pad on the dest filter
  478. enum AVMediaType type; ///< filter media type
  479. /* These parameters apply only to video */
  480. int w; ///< agreed upon image width
  481. int h; ///< agreed upon image height
  482. AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
  483. /* These two parameters apply only to audio */
  484. uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h)
  485. int sample_rate; ///< samples per second
  486. int format; ///< agreed upon media format
  487. /**
  488. * Define the time base used by the PTS of the frames/samples
  489. * which will pass through this link.
  490. * During the configuration stage, each filter is supposed to
  491. * change only the output timebase, while the timebase of the
  492. * input link is assumed to be an unchangeable property.
  493. */
  494. AVRational time_base;
  495. /*****************************************************************
  496. * All fields below this line are not part of the public API. They
  497. * may not be used outside of libavfilter and can be changed and
  498. * removed at will.
  499. * New public fields should be added right above.
  500. *****************************************************************
  501. */
  502. /**
  503. * Lists of formats supported by the input and output filters respectively.
  504. * These lists are used for negotiating the format to actually be used,
  505. * which will be loaded into the format member, above, when chosen.
  506. */
  507. AVFilterFormats *in_formats;
  508. AVFilterFormats *out_formats;
  509. /**
  510. * Lists of channel layouts and sample rates used for automatic
  511. * negotiation.
  512. */
  513. AVFilterFormats *in_samplerates;
  514. AVFilterFormats *out_samplerates;
  515. struct AVFilterChannelLayouts *in_channel_layouts;
  516. struct AVFilterChannelLayouts *out_channel_layouts;
  517. /**
  518. * Audio only, the destination filter sets this to a non-zero value to
  519. * request that buffers with the given number of samples should be sent to
  520. * it. AVFilterPad.needs_fifo must also be set on the corresponding input
  521. * pad.
  522. * Last buffer before EOF will be padded with silence.
  523. */
  524. int request_samples;
  525. /** stage of the initialization of the link properties (dimensions, etc) */
  526. enum {
  527. AVLINK_UNINIT = 0, ///< not started
  528. AVLINK_STARTINIT, ///< started, but incomplete
  529. AVLINK_INIT ///< complete
  530. } init_state;
  531. };
  532. /**
  533. * Link two filters together.
  534. *
  535. * @param src the source filter
  536. * @param srcpad index of the output pad on the source filter
  537. * @param dst the destination filter
  538. * @param dstpad index of the input pad on the destination filter
  539. * @return zero on success
  540. */
  541. int avfilter_link(AVFilterContext *src, unsigned srcpad,
  542. AVFilterContext *dst, unsigned dstpad);
  543. /**
  544. * Negotiate the media format, dimensions, etc of all inputs to a filter.
  545. *
  546. * @param filter the filter to negotiate the properties for its inputs
  547. * @return zero on successful negotiation
  548. */
  549. int avfilter_config_links(AVFilterContext *filter);
  550. #if FF_API_AVFILTERBUFFER
  551. /**
  552. * Create a buffer reference wrapped around an already allocated image
  553. * buffer.
  554. *
  555. * @param data pointers to the planes of the image to reference
  556. * @param linesize linesizes for the planes of the image to reference
  557. * @param perms the required access permissions
  558. * @param w the width of the image specified by the data and linesize arrays
  559. * @param h the height of the image specified by the data and linesize arrays
  560. * @param format the pixel format of the image specified by the data and linesize arrays
  561. */
  562. attribute_deprecated
  563. AVFilterBufferRef *
  564. avfilter_get_video_buffer_ref_from_arrays(uint8_t *data[4], int linesize[4], int perms,
  565. int w, int h, enum AVPixelFormat format);
  566. /**
  567. * Create an audio buffer reference wrapped around an already
  568. * allocated samples buffer.
  569. *
  570. * @param data pointers to the samples plane buffers
  571. * @param linesize linesize for the samples plane buffers
  572. * @param perms the required access permissions
  573. * @param nb_samples number of samples per channel
  574. * @param sample_fmt the format of each sample in the buffer to allocate
  575. * @param channel_layout the channel layout of the buffer
  576. */
  577. attribute_deprecated
  578. AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays(uint8_t **data,
  579. int linesize,
  580. int perms,
  581. int nb_samples,
  582. enum AVSampleFormat sample_fmt,
  583. uint64_t channel_layout);
  584. #endif
  585. /** Initialize the filter system. Register all builtin filters. */
  586. void avfilter_register_all(void);
  587. #if FF_API_OLD_FILTER_REGISTER
  588. /** Uninitialize the filter system. Unregister all filters. */
  589. attribute_deprecated
  590. void avfilter_uninit(void);
  591. #endif
  592. /**
  593. * Register a filter. This is only needed if you plan to use
  594. * avfilter_get_by_name later to lookup the AVFilter structure by name. A
  595. * filter can still by instantiated with avfilter_graph_alloc_filter even if it
  596. * is not registered.
  597. *
  598. * @param filter the filter to register
  599. * @return 0 if the registration was succesfull, a negative value
  600. * otherwise
  601. */
  602. int avfilter_register(AVFilter *filter);
  603. /**
  604. * Get a filter definition matching the given name.
  605. *
  606. * @param name the filter name to find
  607. * @return the filter definition, if any matching one is registered.
  608. * NULL if none found.
  609. */
  610. AVFilter *avfilter_get_by_name(const char *name);
  611. /**
  612. * Iterate over all registered filters.
  613. * @return If prev is non-NULL, next registered filter after prev or NULL if
  614. * prev is the last filter. If prev is NULL, return the first registered filter.
  615. */
  616. const AVFilter *avfilter_next(const AVFilter *prev);
  617. #if FF_API_OLD_FILTER_REGISTER
  618. /**
  619. * If filter is NULL, returns a pointer to the first registered filter pointer,
  620. * if filter is non-NULL, returns the next pointer after filter.
  621. * If the returned pointer points to NULL, the last registered filter
  622. * was already reached.
  623. * @deprecated use avfilter_next()
  624. */
  625. attribute_deprecated
  626. AVFilter **av_filter_next(AVFilter **filter);
  627. #endif
  628. #if FF_API_AVFILTER_OPEN
  629. /**
  630. * Create a filter instance.
  631. *
  632. * @param filter_ctx put here a pointer to the created filter context
  633. * on success, NULL on failure
  634. * @param filter the filter to create an instance of
  635. * @param inst_name Name to give to the new instance. Can be NULL for none.
  636. * @return >= 0 in case of success, a negative error code otherwise
  637. * @deprecated use avfilter_graph_alloc_filter() instead
  638. */
  639. attribute_deprecated
  640. int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name);
  641. #endif
  642. #if FF_API_AVFILTER_INIT_FILTER
  643. /**
  644. * Initialize a filter.
  645. *
  646. * @param filter the filter to initialize
  647. * @param args A string of parameters to use when initializing the filter.
  648. * The format and meaning of this string varies by filter.
  649. * @param opaque Any extra non-string data needed by the filter. The meaning
  650. * of this parameter varies by filter.
  651. * @return zero on success
  652. */
  653. attribute_deprecated
  654. int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
  655. #endif
  656. /**
  657. * Initialize a filter with the supplied parameters.
  658. *
  659. * @param ctx uninitialized filter context to initialize
  660. * @param args Options to initialize the filter with. This must be a
  661. * ':'-separated list of options in the 'key=value' form.
  662. * May be NULL if the options have been set directly using the
  663. * AVOptions API or there are no options that need to be set.
  664. * @return 0 on success, a negative AVERROR on failure
  665. */
  666. int avfilter_init_str(AVFilterContext *ctx, const char *args);
  667. /**
  668. * Initialize a filter with the supplied dictionary of options.
  669. *
  670. * @param ctx uninitialized filter context to initialize
  671. * @param options An AVDictionary filled with options for this filter. On
  672. * return this parameter will be destroyed and replaced with
  673. * a dict containing options that were not found. This dictionary
  674. * must be freed by the caller.
  675. * May be NULL, then this function is equivalent to
  676. * avfilter_init_str() with the second parameter set to NULL.
  677. * @return 0 on success, a negative AVERROR on failure
  678. *
  679. * @note This function and avfilter_init_str() do essentially the same thing,
  680. * the difference is in manner in which the options are passed. It is up to the
  681. * calling code to choose whichever is more preferable. The two functions also
  682. * behave differently when some of the provided options are not declared as
  683. * supported by the filter. In such a case, avfilter_init_str() will fail, but
  684. * this function will leave those extra options in the options AVDictionary and
  685. * continue as usual.
  686. */
  687. int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options);
  688. /**
  689. * Free a filter context. This will also remove the filter from its
  690. * filtergraph's list of filters.
  691. *
  692. * @param filter the filter to free
  693. */
  694. void avfilter_free(AVFilterContext *filter);
  695. /**
  696. * Insert a filter in the middle of an existing link.
  697. *
  698. * @param link the link into which the filter should be inserted
  699. * @param filt the filter to be inserted
  700. * @param filt_srcpad_idx the input pad on the filter to connect
  701. * @param filt_dstpad_idx the output pad on the filter to connect
  702. * @return zero on success
  703. */
  704. int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
  705. unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
  706. #if FF_API_AVFILTERBUFFER
  707. /**
  708. * Copy the frame properties of src to dst, without copying the actual
  709. * image data.
  710. *
  711. * @return 0 on success, a negative number on error.
  712. */
  713. attribute_deprecated
  714. int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src);
  715. /**
  716. * Copy the frame properties and data pointers of src to dst, without copying
  717. * the actual data.
  718. *
  719. * @return 0 on success, a negative number on error.
  720. */
  721. attribute_deprecated
  722. int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src);
  723. #endif
  724. /**
  725. * @return AVClass for AVFilterContext.
  726. *
  727. * @see av_opt_find().
  728. */
  729. const AVClass *avfilter_get_class(void);
  730. typedef struct AVFilterGraphInternal AVFilterGraphInternal;
  731. typedef struct AVFilterGraph {
  732. const AVClass *av_class;
  733. #if FF_API_FOO_COUNT
  734. attribute_deprecated
  735. unsigned filter_count;
  736. #endif
  737. AVFilterContext **filters;
  738. #if !FF_API_FOO_COUNT
  739. unsigned nb_filters;
  740. #endif
  741. char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
  742. char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters
  743. #if FF_API_FOO_COUNT
  744. unsigned nb_filters;
  745. #endif
  746. /**
  747. * Type of multithreading allowed for filters in this graph. A combination
  748. * of AVFILTER_THREAD_* flags.
  749. *
  750. * May be set by the caller at any point, the setting will apply to all
  751. * filters initialized after that. The default is allowing everything.
  752. *
  753. * When a filter in this graph is initialized, this field is combined using
  754. * bit AND with AVFilterContext.thread_type to get the final mask used for
  755. * determining allowed threading types. I.e. a threading type needs to be
  756. * set in both to be allowed.
  757. */
  758. int thread_type;
  759. /**
  760. * Maximum number of threads used by filters in this graph. May be set by
  761. * the caller before adding any filters to the filtergraph. Zero (the
  762. * default) means that the number of threads is determined automatically.
  763. */
  764. int nb_threads;
  765. /**
  766. * Opaque object for libavfilter internal use.
  767. */
  768. AVFilterGraphInternal *internal;
  769. } AVFilterGraph;
  770. /**
  771. * Allocate a filter graph.
  772. */
  773. AVFilterGraph *avfilter_graph_alloc(void);
  774. /**
  775. * Create a new filter instance in a filter graph.
  776. *
  777. * @param graph graph in which the new filter will be used
  778. * @param filter the filter to create an instance of
  779. * @param name Name to give to the new instance (will be copied to
  780. * AVFilterContext.name). This may be used by the caller to identify
  781. * different filters, libavfilter itself assigns no semantics to
  782. * this parameter. May be NULL.
  783. *
  784. * @return the context of the newly created filter instance (note that it is
  785. * also retrievable directly through AVFilterGraph.filters or with
  786. * avfilter_graph_get_filter()) on success or NULL or failure.
  787. */
  788. AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph,
  789. const AVFilter *filter,
  790. const char *name);
  791. /**
  792. * Get a filter instance with name name from graph.
  793. *
  794. * @return the pointer to the found filter instance or NULL if it
  795. * cannot be found.
  796. */
  797. AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name);
  798. #if FF_API_AVFILTER_OPEN
  799. /**
  800. * Add an existing filter instance to a filter graph.
  801. *
  802. * @param graphctx the filter graph
  803. * @param filter the filter to be added
  804. *
  805. * @deprecated use avfilter_graph_alloc_filter() to allocate a filter in a
  806. * filter graph
  807. */
  808. attribute_deprecated
  809. int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
  810. #endif
  811. /**
  812. * Create and add a filter instance into an existing graph.
  813. * The filter instance is created from the filter filt and inited
  814. * with the parameters args and opaque.
  815. *
  816. * In case of success put in *filt_ctx the pointer to the created
  817. * filter instance, otherwise set *filt_ctx to NULL.
  818. *
  819. * @param name the instance name to give to the created filter instance
  820. * @param graph_ctx the filter graph
  821. * @return a negative AVERROR error code in case of failure, a non
  822. * negative value otherwise
  823. */
  824. int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
  825. const char *name, const char *args, void *opaque,
  826. AVFilterGraph *graph_ctx);
  827. /**
  828. * Check validity and configure all the links and formats in the graph.
  829. *
  830. * @param graphctx the filter graph
  831. * @param log_ctx context used for logging
  832. * @return 0 in case of success, a negative AVERROR code otherwise
  833. */
  834. int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
  835. /**
  836. * Free a graph, destroy its links, and set *graph to NULL.
  837. * If *graph is NULL, do nothing.
  838. */
  839. void avfilter_graph_free(AVFilterGraph **graph);
  840. /**
  841. * A linked-list of the inputs/outputs of the filter chain.
  842. *
  843. * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
  844. * where it is used to communicate open (unlinked) inputs and outputs from and
  845. * to the caller.
  846. * This struct specifies, per each not connected pad contained in the graph, the
  847. * filter context and the pad index required for establishing a link.
  848. */
  849. typedef struct AVFilterInOut {
  850. /** unique name for this input/output in the list */
  851. char *name;
  852. /** filter context associated to this input/output */
  853. AVFilterContext *filter_ctx;
  854. /** index of the filt_ctx pad to use for linking */
  855. int pad_idx;
  856. /** next input/input in the list, NULL if this is the last */
  857. struct AVFilterInOut *next;
  858. } AVFilterInOut;
  859. /**
  860. * Allocate a single AVFilterInOut entry.
  861. * Must be freed with avfilter_inout_free().
  862. * @return allocated AVFilterInOut on success, NULL on failure.
  863. */
  864. AVFilterInOut *avfilter_inout_alloc(void);
  865. /**
  866. * Free the supplied list of AVFilterInOut and set *inout to NULL.
  867. * If *inout is NULL, do nothing.
  868. */
  869. void avfilter_inout_free(AVFilterInOut **inout);
  870. /**
  871. * Add a graph described by a string to a graph.
  872. *
  873. * @param graph the filter graph where to link the parsed graph context
  874. * @param filters string to be parsed
  875. * @param inputs linked list to the inputs of the graph
  876. * @param outputs linked list to the outputs of the graph
  877. * @return zero on success, a negative AVERROR code on error
  878. */
  879. int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
  880. AVFilterInOut *inputs, AVFilterInOut *outputs,
  881. void *log_ctx);
  882. /**
  883. * Add a graph described by a string to a graph.
  884. *
  885. * @param[in] graph the filter graph where to link the parsed graph context
  886. * @param[in] filters string to be parsed
  887. * @param[out] inputs a linked list of all free (unlinked) inputs of the
  888. * parsed graph will be returned here. It is to be freed
  889. * by the caller using avfilter_inout_free().
  890. * @param[out] outputs a linked list of all free (unlinked) outputs of the
  891. * parsed graph will be returned here. It is to be freed by the
  892. * caller using avfilter_inout_free().
  893. * @return zero on success, a negative AVERROR code on error
  894. *
  895. * @note the difference between avfilter_graph_parse2() and
  896. * avfilter_graph_parse() is that in avfilter_graph_parse(), the caller provides
  897. * the lists of inputs and outputs, which therefore must be known before calling
  898. * the function. On the other hand, avfilter_graph_parse2() \em returns the
  899. * inputs and outputs that are left unlinked after parsing the graph and the
  900. * caller then deals with them. Another difference is that in
  901. * avfilter_graph_parse(), the inputs parameter describes inputs of the
  902. * <em>already existing</em> part of the graph; i.e. from the point of view of
  903. * the newly created part, they are outputs. Similarly the outputs parameter
  904. * describes outputs of the already existing filters, which are provided as
  905. * inputs to the parsed filters.
  906. * avfilter_graph_parse2() takes the opposite approach -- it makes no reference
  907. * whatsoever to already existing parts of the graph and the inputs parameter
  908. * will on return contain inputs of the newly parsed part of the graph.
  909. * Analogously the outputs parameter will contain outputs of the newly created
  910. * filters.
  911. */
  912. int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
  913. AVFilterInOut **inputs,
  914. AVFilterInOut **outputs);
  915. /**
  916. * @}
  917. */
  918. #endif /* AVFILTER_AVFILTER_H */