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 module ffmpeg.libavfilter.avfilter;
23 
24 /**
25  * @file
26  * @ingroup lavfi
27  * Main libavfilter public API header
28  */
29 
30 /**
31  * @defgroup lavfi Libavfilter - graph-based frame editing library
32  * @{
33  */
34 
35 import std.stdint;
36 import std.bitmanip;
37 import core.vararg;
38 import ffmpeg.libavutil.avutil;
39 import ffmpeg.libavutil.samplefmt;
40 import ffmpeg.libavcodec.avcodec;
41 import ffmpeg.libavfilter.internal;
42 import ffmpeg.libavfilter.formats;
43 import ffmpeg.libavfilter.avfilter_version;
44 
45 extern(C):
46 /**
47 * Return the LIBAVFILTER_VERSION_INT constant.
48 */
49 uint avfilter_version();
50 
51 /**
52  * Return the libavfilter build-time configuration.
53  */
54 char *avfilter_configuration();
55 
56 /**
57  * Return the libavfilter license.
58  */
59 char *avfilter_license();
60 
61 //typedef struct AVFilterContext AVFilterContext;
62 //typedef struct AVFilterLink AVFilterLink;
63 //typedef struct AVFilterPad AVFilterPad;
64 struct AVFilterFormats;
65 
66 static if (FF_API_AVFILTERBUFFER) {
67 /**
68  * A reference-counted buffer data type used by the filter system. Filters
69  * should not store pointers to this structure directly, but instead use the
70  * AVFilterBufferRef structure below.
71  */
72 struct AVFilterBuffer {
73     uint8_t *[8]data;           ///< buffer data for each plane/channel
74 
75     /**
76      * pointers to the data planes/channels.
77      *
78      * For video, this should simply point to data[].
79      *
80      * For planar audio, each channel has a separate data pointer, and
81      * linesize[0] contains the size of each channel buffer.
82      * For packed audio, there is just one data pointer, and linesize[0]
83      * contains the total size of the buffer for all channels.
84      *
85      * Note: Both data and extended_data will always be set, but for planar
86      * audio with more channels that can fit in data, extended_data must be used
87      * in order to access all channels.
88      */
89     uint8_t **extended_data;
90     int [8]linesize;            ///< number of bytes per line
91 
92     /** private data to be used by a custom free function */
93     void *priv;
94     /**
95      * A pointer to the function to deallocate this buffer if the default
96      * function is not sufficient. This could, for example, add the memory
97      * back into a memory pool to be reused later without the overhead of
98      * reallocating it from scratch.
99      */
100     void function(AVFilterBuffer *buf) free;
101 
102     int format;                 ///< media format
103     int w, h;                   ///< width and height of the allocated buffer
104     uint refcount;          ///< number of references to this buffer
105 }
106 
107 const uint AV_PERM_READ  =  0x01;  ///< can read from the buffer
108 const uint AV_PERM_WRITE  = 0x02;  ///< can write to the buffer
109 const uint AV_PERM_PRESERVE=0x04;  ///< nobody else can overwrite the buffer
110 const uint AV_PERM_REUSE =  0x08;  ///< can output the buffer multiple times, with the same contents each time
111 const uint AV_PERM_REUSE2 = 0x10;  ///< can output the buffer multiple times, modified each time
112 const uint AV_PERM_NEG_LINESIZES=0x20; ///< the buffer requested can have negative linesizes
113 const uint AV_PERM_ALIGN =  0x40;  ///< the buffer must be aligned
114 
115 const uint AVFILTER_ALIGN=16;//not part of ABI
116 
117 /**
118  * Audio specific properties in a reference to an AVFilterBuffer. Since
119  * AVFilterBufferRef is common to different media formats, audio specific
120  * per reference properties must be separated out.
121  */
122 struct AVFilterBufferRefAudioProps {
123     uint64_t channel_layout;    ///< channel layout of audio buffer
124     int nb_samples;             ///< number of audio samples per channel
125     int sample_rate;            ///< audio buffer sample rate
126     int channels;               ///< number of channels (do not access directly)
127 }
128 
129 /**
130  * Video specific properties in a reference to an AVFilterBuffer. Since
131  * AVFilterBufferRef is common to different media formats, video specific
132  * per reference properties must be separated out.
133  */
134 struct AVFilterBufferRefVideoProps {
135     int w;                      ///< image width
136     int h;                      ///< image height
137     AVRational sample_aspect_ratio; ///< sample aspect ratio
138     int interlaced;             ///< is frame interlaced
139     int top_field_first;        ///< field order
140     AVPictureType pict_type; ///< picture type of the frame
141     int key_frame;              ///< 1 -> keyframe, 0-> not
142     int qp_table_linesize;                ///< qp_table stride
143     int qp_table_size;            ///< qp_table size
144     int8_t *qp_table;
145 }
146 
147 /**
148  * A reference to an AVFilterBuffer. Since filters can manipulate the origin of
149  * a buffer to, for example, crop image without any memcpy, the buffer origin
150  * and dimensions are per-reference properties. Linesize is also useful for
151  * image flipping, frame to field filters, etc, and so is also per-reference.
152  *
153  * TODO: add anything necessary for frame reordering
154  */
155 struct AVFilterBufferRef {
156     AVFilterBuffer *buf;        ///< the buffer that this is a reference to
157     uint8_t *[8]data;           ///< picture/audio data for each plane
158     /**
159      * pointers to the data planes/channels.
160      *
161      * For video, this should simply point to data[].
162      *
163      * For planar audio, each channel has a separate data pointer, and
164      * linesize[0] contains the size of each channel buffer.
165      * For packed audio, there is just one data pointer, and linesize[0]
166      * contains the total size of the buffer for all channels.
167      *
168      * Note: Both data and extended_data will always be set, but for planar
169      * audio with more channels that can fit in data, extended_data must be used
170      * in order to access all channels.
171      */
172     uint8_t **extended_data;
173     int [8]linesize;            ///< number of bytes per line
174 
175     AVFilterBufferRefVideoProps *video; ///< video buffer specific properties
176     AVFilterBufferRefAudioProps *audio; ///< audio buffer specific properties
177 
178     /**
179      * presentation timestamp. The time unit may change during
180      * filtering, as it is specified in the link and the filter code
181      * may need to rescale the PTS accordingly.
182      */
183     int64_t pts;
184     int64_t pos;                ///< byte position in stream, -1 if unknown
185 
186     int format;                 ///< media format
187 
188     int perms;                  ///< permissions, see the AV_PERM_* flags
189 
190     AVMediaType type;      ///< media type of buffer data
191 
192     AVDictionary *metadata;     ///< dictionary containing metadata key=value tags
193 }
194 
195 /**
196  * Copy properties of src to dst, without copying the actual data
197  */
198 deprecated
199 void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, const AVFilterBufferRef *src);
200 
201 /**
202  * Add a new reference to a buffer.
203  *
204  * @param ref   an existing reference to the buffer
205  * @param pmask a bitmask containing the allowable permissions in the new
206  *              reference
207  * @return      a new reference to the buffer with the same properties as the
208  *              old, excluding any permissions denied by pmask
209  */
210 deprecated
211 AVFilterBufferRef *avfilter_ref_buffer(AVFilterBufferRef *_ref, int pmask);
212 
213 /**
214  * Remove a reference to a buffer. If this is the last reference to the
215  * buffer, the buffer itself is also automatically freed.
216  *
217  * @param ref reference to the buffer, may be NULL
218  *
219  * @note it is recommended to use avfilter_unref_bufferp() instead of this
220  * function
221  */
222 deprecated
223 void avfilter_unref_buffer(AVFilterBufferRef *_ref);
224 
225 /**
226  * Remove a reference to a buffer and set the pointer to NULL.
227  * If this is the last reference to the buffer, the buffer itself
228  * is also automatically freed.
229  *
230  * @param ref pointer to the buffer reference
231  */
232 deprecated
233 void avfilter_unref_bufferp(AVFilterBufferRef **_ref);
234 }
235 
236 /**
237  * Get the number of channels of a buffer reference.
238  */
239 deprecated
240 int avfilter_ref_get_channels(AVFilterBufferRef *_ref);
241 
242 static if(FF_API_AVFILTERPAD_PUBLIC) {
243 /**
244  * A filter pad used for either input or output.
245  *
246  * See doc/filter_design.txt for details on how to implement the methods.
247  *
248  * @warning this struct might be removed from public API.
249  * users should call avfilter_pad_get_name() and avfilter_pad_get_type()
250  * to access the name and type fields; there should be no need to access
251  * any other fields from outside of libavfilter.
252  */
253   struct AVFilterPad {
254     /**
255      * Pad name. The name is unique among inputs and among outputs, but an
256      * input may have the same name as an output. This may be NULL if this
257      * pad has no need to ever be referenced by name.
258      */
259     const char *name;
260 
261     /**
262      * AVFilterPad type.
263      */
264     AVMediaType type;
265 
266     /**
267      * Input pads:
268      * Minimum required permissions on incoming buffers. Any buffer with
269      * insufficient permissions will be automatically copied by the filter
270      * system to a new buffer which provides the needed access permissions.
271      *
272      * Output pads:
273      * Guaranteed permissions on outgoing buffers. Any buffer pushed on the
274      * link must have at least these permissions; this fact is checked by
275      * asserts. It can be used to optimize buffer allocation.
276      */
277     deprecated int min_perms;
278 
279     /**
280      * Input pads:
281      * Permissions which are not accepted on incoming buffers. Any buffer
282      * which has any of these permissions set will be automatically copied
283      * by the filter system to a new buffer which does not have those
284      * permissions. This can be used to easily disallow buffers with
285      * AV_PERM_REUSE.
286      *
287      * Output pads:
288      * Permissions which are automatically removed on outgoing buffers. It
289      * can be used to optimize buffer allocation.
290      */
291     deprecated int rej_perms;
292 
293     /**
294      * @deprecated unused
295      */
296     deprecated void function (AVFilterLink *link, AVFilterBufferRef *picref) start_frame;
297 
298     /**
299      * Callback function to get a video buffer. If NULL, the filter system will
300      * use ff_default_get_video_buffer().
301      *
302      * Input video pads only.
303      */
304     AVFrame* function (AVFilterLink *link, int perms, int w, int h) get_video_buffer;
305 
306     /**
307      * Callback function to get an audio buffer. If NULL, the filter system will
308      * use ff_default_get_audio_buffer().
309      *
310      * Input audio pads only.
311      */
312     AVFrame* function (AVFilterLink *link, int perms, int nb_samples) get_audio_buffer;
313 
314     /**
315      * @deprecated unused
316      */
317     deprecated void function (AVFilterLink *link) end_frame;
318 
319     /**
320      * @deprecated unused
321      */
322     deprecated void function (AVFilterLink *link, int y, int height, int slice_dir) draw_slice;
323 
324     /**
325      * Filtering callback. This is where a filter receives a frame with
326      * audio/video data and should do its processing.
327      *
328      * Input pads only.
329      *
330      * @return >= 0 on success, a negative AVERROR on error. This function
331      * must ensure that frame is properly unreferenced on error if it
332      * hasn't been passed on to another filter.
333      */
334     int function (AVFilterLink *link, AVFrame *frame) filter_frame;
335 
336     /**
337      * Frame poll callback. This returns the number of immediately available
338      * samples. It should return a positive value if the next request_frame()
339      * is guaranteed to return one frame (with no delay).
340      *
341      * Defaults to just calling the source poll_frame() method.
342      *
343      * Output pads only.
344      */
345     int function(AVFilterLink *link) poll_frame;
346 
347     /**
348      * Frame request callback. A call to this should result in at least one
349      * frame being output over the given link. This should return zero on
350      * success, and another value on error.
351      * See ff_request_frame() for the error codes with a specific
352      * meaning.
353      *
354      * Output pads only.
355      */
356     int function(AVFilterLink *link) request_frame;
357 
358     /**
359      * Link configuration callback.
360      *
361      * For output pads, this should set the following link properties:
362      * video: width, height, sample_aspect_ratio, time_base
363      * audio: sample_rate.
364      *
365      * This should NOT set properties such as format, channel_layout, etc which
366      * are negotiated between filters by the filter system using the
367      * query_formats() callback before this function is called.
368      *
369      * For input pads, this should check the properties of the link, and update
370      * the filter's internal state as necessary.
371      *
372      * For both input and output pads, this should return zero on success,
373      * and another value on error.
374      */
375     int function (AVFilterLink *link) config_props;
376 
377     /**
378      * The filter expects a fifo to be inserted on its input link,
379      * typically because it has a delay.
380      *
381      * input pads only.
382      */
383     int needs_fifo;
384 
385     /**
386      * The filter expects writable frames from its input link,
387      * duplicating data buffers if needed.
388      *
389      * input pads only.
390      */
391     int needs_writable;
392 }
393 }
394 
395 /**
396  * Get the number of elements in a NULL-terminated array of AVFilterPads (e.g.
397  * AVFilter.inputs/outputs).
398  */
399 int avfilter_pad_count(const AVFilterPad *pads);
400 
401 /**
402  * Get the name of an AVFilterPad.
403  *
404  * @param pads an array of AVFilterPads
405  * @param pad_idx index of the pad in the array it; is the caller's
406  *                responsibility to ensure the index is valid
407  *
408  * @return name of the pad_idx'th pad in pads
409  */
410 char *avfilter_pad_get_name(AVFilterPad *pads, int pad_idx);
411 
412 /**
413  * Get the type of an AVFilterPad.
414  *
415  * @param pads an array of AVFilterPads
416  * @param pad_idx index of the pad in the array; it is the caller's
417  *                responsibility to ensure the index is valid
418  *
419  * @return type of the pad_idx'th pad in pads
420  */
421  AVMediaType avfilter_pad_get_type(AVFilterPad *pads, int pad_idx);
422 
423 /**
424  * The number of the filter inputs is not determined just by AVFilter.inputs.
425  * The filter might add additional inputs during initialization depending on the
426  * options supplied to it.
427  */
428 enum AVFILTER_FLAG_DYNAMIC_INPUTS   =    (1 << 0);
429 /**
430  * The number of the filter outputs is not determined just by AVFilter.outputs.
431  * The filter might add additional outputs during initialization depending on
432  * the options supplied to it.
433  */
434 enum AVFILTER_FLAG_DYNAMIC_OUTPUTS  =    (1 << 1);
435 /**
436  * The filter supports multithreading by splitting frames into multiple parts
437  * and processing them concurrently.
438  */
439 enum AVFILTER_FLAG_SLICE_THREADS     =   (1 << 2);
440 /**
441  * Some filters support a generic "enable" expression option that can be used
442  * to enable or disable a filter in the timeline. Filters supporting this
443  * option have this flag set. When the enable expression is false, the default
444  * no-op filter_frame() function is called in place of the filter_frame()
445  * callback defined on each input pad, thus the frame is passed unchanged to
446  * the next filters.
447  */
448 enum AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC= (1 << 16);
449 /**
450  * Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will
451  * have its filter_frame() callback(s) called as usual even when the enable
452  * expression is false. The filter will disable filtering within the
453  * filter_frame() callback(s) itself, for example executing code depending on
454  * the AVFilterContext->is_disabled value.
455  */
456 enum AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL=(1 << 17);
457 /**
458  * Handy mask to test whether the filter supports or no the timeline feature
459  * (internally or generically).
460  */
461 enum AVFILTER_FLAG_SUPPORT_TIMELINE=(AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL);
462 
463 /**
464  * Filter definition. This defines the pads a filter contains, and all the
465  * callback functions used to interact with the filter.
466  */
467 struct AVFilter {
468     /**
469      * Filter name. Must be non-NULL and unique among filters.
470      */
471     const char *name;
472 
473     /**
474      * A description of the filter. May be NULL.
475      *
476      * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
477      */
478     const char *description;
479 
480     /**
481      * List of inputs, terminated by a zeroed element.
482      *
483      * NULL if there are no (static) inputs. Instances of filters with
484      * AVFILTER_FLAG_DYNAMIC_INPUTS set may have more inputs than present in
485      * this list.
486      */
487     const AVFilterPad *inputs;
488     /**
489      * List of outputs, terminated by a zeroed element.
490      *
491      * NULL if there are no (static) outputs. Instances of filters with
492      * AVFILTER_FLAG_DYNAMIC_OUTPUTS set may have more outputs than present in
493      * this list.
494      */
495     const AVFilterPad *outputs;
496 
497     /**
498      * A class for the private data, used to declare filter private AVOptions.
499      * This field is NULL for filters that do not declare any options.
500      *
501      * If this field is non-NULL, the first member of the filter private data
502      * must be a pointer to AVClass, which will be set by libavfilter generic
503      * code to this class.
504      */
505     const AVClass *priv_class;
506 
507     /**
508      * A combination of AVFILTER_FLAG_*
509      */
510     int flags;
511 
512     /*****************************************************************
513      * All fields below this line are not part of the public API. They
514      * may not be used outside of libavfilter and can be changed and
515      * removed at will.
516      * New public fields should be added right above.
517      *****************************************************************
518      */
519 
520     /**
521      * Filter initialization function.
522      *
523      * This callback will be called only once during the filter lifetime, after
524      * all the options have been set, but before links between filters are
525      * established and format negotiation is done.
526      *
527      * Basic filter initialization should be done here. Filters with dynamic
528      * inputs and/or outputs should create those inputs/outputs here based on
529      * provided options. No more changes to this filter's inputs/outputs can be
530      * done after this callback.
531      *
532      * This callback must not assume that the filter links exist or frame
533      * parameters are known.
534      *
535      * @ref AVFilter.uninit "uninit" is guaranteed to be called even if
536      * initialization fails, so this callback does not have to clean up on
537      * failure.
538      *
539      * @return 0 on success, a negative AVERROR on failure
540      */
541     int function(AVFilterContext *ctx) init;
542 
543     /**
544      * Should be set instead of @ref AVFilter.init "init" by the filters that
545      * want to pass a dictionary of AVOptions to nested contexts that are
546      * allocated during init.
547      *
548      * On return, the options dict should be freed and replaced with one that
549      * contains all the options which could not be processed by this filter (or
550      * with NULL if all the options were processed).
551      *
552      * Otherwise the semantics is the same as for @ref AVFilter.init "init".
553      */
554     int function(AVFilterContext *ctx, AVDictionary **options) init_dict;
555 
556     /**
557      * Filter uninitialization function.
558      *
559      * Called only once right before the filter is freed. Should deallocate any
560      * memory held by the filter, release any buffer references, etc. It does
561      * not need to deallocate the AVFilterContext.priv memory itself.
562      *
563      * This callback may be called even if @ref AVFilter.init "init" was not
564      * called or failed, so it must be prepared to handle such a situation.
565      */
566     void function(AVFilterContext *ctx) uninit;
567 
568     /**
569      * Query formats supported by the filter on its inputs and outputs.
570      *
571      * This callback is called after the filter is initialized (so the inputs
572      * and outputs are fixed), shortly before the format negotiation. This
573      * callback may be called more than once.
574      *
575      * This callback must set AVFilterLink.out_formats on every input link and
576      * AVFilterLink.in_formats on every output link to a list of pixel/sample
577      * formats that the filter supports on that link. For audio links, this
578      * filter must also set @ref AVFilterLink.in_samplerates "in_samplerates" /
579      * @ref AVFilterLink.out_samplerates "out_samplerates" and
580      * @ref AVFilterLink.in_channel_layouts "in_channel_layouts" /
581      * @ref AVFilterLink.out_channel_layouts "out_channel_layouts" analogously.
582      *
583      * This callback may be NULL for filters with one input, in which case
584      * libavfilter assumes that it supports all input formats and preserves
585      * them on output.
586      *
587      * @return zero on success, a negative value corresponding to an
588      * AVERROR code otherwise
589      */
590     int function(AVFilterContext *) query_formats;  
591 
592     int priv_size;      ///< size of private data to allocate for the filter
593 
594     /**
595      * Used by the filter registration system. Must not be touched by any other
596      * code.
597      */
598     AVFilter *next;
599 
600     /**
601      * Make the filter instance process a command.
602      *
603      * @param cmd    the command to process, for handling simplicity all commands must be alphanumeric only
604      * @param arg    the argument for the command
605      * @param res    a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported.
606      * @param flags  if AVFILTER_CMD_FLAG_FAST is set and the command would be
607      *               time consuming then a filter should treat it like an unsupported command
608      *
609      * @returns >=0 on success otherwise an error code.
610      *          AVERROR(ENOSYS) on unsupported commands
611      */
612     int function(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags) process_command;
613     
614     /**
615      * Filter initialization function, alternative to the init()
616      * callback. Args contains the user-supplied parameters, opaque is
617      * used for providing binary data.
618      */
619     int function(AVFilterContext *ctx, void *opaque) init_opaque;
620 }
621 
622 /**
623  * Process multiple parts of the frame concurrently.
624  */
625 enum AVFILTER_THREAD_SLICE=(1 << 0);
626 
627 struct AVFilterInternal;
628 /** An instance of a filter */
629 struct AVFilterContext {
630     const AVClass *av_class;        ///< needed for av_log() and filters common options
631 
632     const AVFilter *filter;         ///< the AVFilter of which this is an instance
633 
634     char *name;                     ///< name of this filter instance
635 
636     AVFilterPad   *input_pads;      ///< array of input pads
637     AVFilterLink **inputs;          ///< array of pointers to input links
638 static if(FF_API_FOO_COUNT) {    
639     deprecated uint input_count; ///< use nb_inputs
640 }
641     uint    nb_inputs;          ///< number of input pads
642 
643     AVFilterPad   *output_pads;     ///< array of output pads
644     AVFilterLink **outputs;         ///< array of pointers to output links
645 static if(FF_API_FOO_COUNT) {    
646     uint output_count;              ///< number of output pads
647 }
648     uint    nb_outputs;
649 
650     void *priv;                     ///< private data for use by the filter
651 
652     AVFilterGraph *graph;    ///< filtergraph this filter belongs to
653 
654     /**
655      * Type of multithreading being allowed/used. A combination of
656      * AVFILTER_THREAD_* flags.
657      *
658      * May be set by the caller before initializing the filter to forbid some
659      * or all kinds of multithreading for this filter. The default is allowing
660      * everything.
661      *
662      * When the filter is initialized, this field is combined using bit AND with
663      * AVFilterGraph.thread_type to get the final mask used for determining
664      * allowed threading types. I.e. a threading type needs to be set in both
665      * to be allowed.
666      *
667      * After the filter is initialized, libavfilter sets this field to the
668      * threading type that is actually used (0 for no multithreading).
669      */
670     int thread_type;
671 
672     /**
673      * An opaque struct for libavfilter internal use.
674      */
675     AVFilterInternal *internal;
676 
677     AVFilterCommand *command_queue;
678 
679     char *enable_str;               ///< enable expression string
680     void *enable;                   ///< parsed expression (AVExpr*)
681     double *var_values;             ///< variable values for the enable expression
682     int is_disabled;                ///< the enabled state from the last expression evaluation
683 };
684 
685 /**
686  * A link between two filters. This contains pointers to the source and
687  * destination filters between which this link exists, and the indexes of
688  * the pads involved. In addition, this link also contains the parameters
689  * which have been negotiated and agreed upon between the filter, such as
690  * image dimensions, format, etc.
691  */
692 struct AVFilterLink {
693     AVFilterContext *src;       ///< source filter
694     AVFilterPad *srcpad;        ///< output pad on the source filter
695 
696     AVFilterContext *dst;       ///< dest filter
697     AVFilterPad *dstpad;        ///< input pad on the dest filter
698 
699     AVMediaType type;      ///< filter media type
700 
701     /* These parameters apply only to video */
702     int w;                      ///< agreed upon image width
703     int h;                      ///< agreed upon image height
704     AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio
705     /* These parameters apply only to audio */
706     uint64_t channel_layout;    ///< channel layout of current buffer (see libavutil/channel_layout.h)
707     int sample_rate;            ///< samples per second
708 
709     int format;                 ///< agreed upon media format
710 
711     /**
712      * Define the time base used by the PTS of the frames/samples
713      * which will pass through this link.
714      * During the configuration stage, each filter is supposed to
715      * change only the output timebase, while the timebase of the
716      * input link is assumed to be an unchangeable property.
717      */
718     AVRational time_base;
719 
720     /*****************************************************************
721      * All fields below this line are not part of the public API. They
722      * may not be used outside of libavfilter and can be changed and
723      * removed at will.
724      * New public fields should be added right above.
725      *****************************************************************
726      */
727     /**
728      * Lists of formats and channel layouts supported by the input and output
729      * filters respectively. These lists are used for negotiating the format
730      * to actually be used, which will be loaded into the format and
731      * channel_layout members, above, when chosen.
732      *
733      */
734     AVFilterFormats *in_formats;
735     AVFilterFormats *out_formats;
736 
737     /**
738      * Lists of channel layouts and sample rates used for automatic
739      * negotiation.
740      */
741     AVFilterFormats  *in_samplerates;
742     AVFilterFormats *out_samplerates;
743     AVFilterChannelLayouts  *in_channel_layouts;
744     AVFilterChannelLayouts *out_channel_layouts;
745 
746     /**
747      * Audio only, the destination filter sets this to a non-zero value to
748      * request that buffers with the given number of samples should be sent to
749      * it. AVFilterPad.needs_fifo must also be set on the corresponding input
750      * pad.
751      * Last buffer before EOF will be padded with silence.
752      */
753     int request_samples;
754 
755     /** stage of the initialization of the link properties (dimensions, etc) */
756     enum init_state {
757         AVLINK_UNINIT = 0,      ///< not started
758         AVLINK_STARTINIT,       ///< started, but incomplete
759         AVLINK_INIT             ///< complete
760     };    
761 
762     AVFilterPool *pool;
763 
764     /**
765      * Graph the filter belongs to.
766      */
767     AVFilterGraph *graph;
768 
769     /**
770      * Current timestamp of the link, as defined by the most recent
771      * frame(s), in AV_TIME_BASE units.
772      */
773     int64_t current_pts;
774 
775     /**
776      * Index in the age array.
777      */
778     int age_index;
779 
780     /**
781      * Frame rate of the stream on the link, or 1/0 if unknown;
782      * if left to 0/0, will be automatically be copied from the first input
783      * of the source filter if it exists.
784      *
785      * Sources should set it to the best estimation of the real frame rate.
786      * Filters should update it if necessary depending on their function.
787      * Sinks can use it to set a default output frame rate.
788      * It is similar to the r_frame_rate field in AVStream.
789      */
790     AVRational frame_rate;
791 
792     /**
793      * Buffer partially filled with samples to achieve a fixed/minimum size.
794      */
795     AVFrame *partial_buf;
796 
797     /**
798      * Size of the partial buffer to allocate.
799      * Must be between min_samples and max_samples.
800      */
801     int partial_buf_size;
802 
803     /**
804      * Minimum number of samples to filter at once. If filter_frame() is
805      * called with fewer samples, it will accumulate them in partial_buf.
806      * This field and the related ones must not be changed after filtering
807      * has started.
808      * If 0, all related fields are ignored.
809      */
810     int min_samples;
811 
812     /**
813      * Maximum number of samples to filter at once. If filter_frame() is
814      * called with more samples, it will split them.
815      */
816     int max_samples;
817 
818     /**
819      * The buffer reference currently being received across the link by the
820      * destination filter. This is used internally by the filter system to
821      * allow automatic copying of buffers which do not have sufficient
822      * permissions for the destination. This should not be accessed directly
823      * by the filters.
824      */
825     AVFilterBufferRef *cur_buf_copy;
826 
827     /**
828      * True if the link is closed.
829      * If set, all attempts of start_frame, filter_frame or request_frame
830      * will fail with AVERROR_EOF, and if necessary the reference will be
831      * destroyed.
832      * If request_frame returns AVERROR_EOF, this flag is set on the
833      * corresponding link.
834      * It can be set also be set by either the source or the destination
835      * filter.
836      */
837     int closed;
838 
839     /**
840      * Number of channels.
841      */
842     int channels;
843 
844     /**
845      * True if a frame is being requested on the link.
846      * Used internally by the framework.
847      */
848     uint frame_requested;
849 
850     /**
851      * Link processing flags.
852      */
853     uint flags;
854 
855     /**
856      * Number of past frames sent through the link.
857      */
858     int64_t frame_count;
859 };
860 
861 /**
862  * Link two filters together.
863  *
864  * @param src    the source filter
865  * @param srcpad index of the output pad on the source filter
866  * @param dst    the destination filter
867  * @param dstpad index of the input pad on the destination filter
868  * @return       zero on success
869  */
870 int avfilter_link(AVFilterContext *src, uint srcpad,
871                   AVFilterContext *dst, uint dstpad);
872 
873 /**
874  * Free the link in *link, and set its pointer to NULL.
875  */
876 void avfilter_link_free(AVFilterLink **link);
877 
878 /**
879  * Get the number of channels of a link.
880  */
881 int avfilter_link_get_channels(AVFilterLink *link);
882 
883 /**
884  * Set the closed field of a link.
885  */
886 void avfilter_link_set_closed(AVFilterLink *link, int closed);
887 
888 /**
889  * Negotiate the media format, dimensions, etc of all inputs to a filter.
890  *
891  * @param filter the filter to negotiate the properties for its inputs
892  * @return       zero on successful negotiation
893  */
894 int avfilter_config_links(AVFilterContext *filter);
895 
896 static if (FF_API_AVFILTERBUFFER) {
897 /**
898  * Create a buffer reference wrapped around an already allocated image
899  * buffer.
900  *
901  * @param data pointers to the planes of the image to reference
902  * @param linesize linesizes for the planes of the image to reference
903  * @param perms the required access permissions
904  * @param w the width of the image specified by the data and linesize arrays
905  * @param h the height of the image specified by the data and linesize arrays
906  * @param format the pixel format of the image specified by the data and linesize arrays
907  */
908 deprecated
909 AVFilterBufferRef *
910 avfilter_get_video_buffer_ref_from_arrays(const uint8_t* [4]data, const int [4]linesize, int perms,
911                                           int w, int h, AVPixelFormat format);
912 
913 /**
914  * Create an audio buffer reference wrapped around an already
915  * allocated samples buffer.
916  *
917  * See avfilter_get_audio_buffer_ref_from_arrays_channels() for a version
918  * that can handle unknown channel layouts.
919  *
920  * @param data           pointers to the samples plane buffers
921  * @param linesize       linesize for the samples plane buffers
922  * @param perms          the required access permissions
923  * @param nb_samples     number of samples per channel
924  * @param sample_fmt     the format of each sample in the buffer to allocate
925  * @param channel_layout the channel layout of the buffer
926  */
927 deprecated
928 AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays(uint8_t **data,
929                                                              int linesize,
930                                                              int perms,
931                                                              int nb_samples,
932                                                              AVSampleFormat sample_fmt,
933                                                              uint64_t channel_layout);
934 /**
935  * Create an audio buffer reference wrapped around an already
936  * allocated samples buffer.
937  *
938  * @param data           pointers to the samples plane buffers
939  * @param linesize       linesize for the samples plane buffers
940  * @param perms          the required access permissions
941  * @param nb_samples     number of samples per channel
942  * @param sample_fmt     the format of each sample in the buffer to allocate
943  * @param channels       the number of channels of the buffer
944  * @param channel_layout the channel layout of the buffer,
945  *                       must be either 0 or consistent with channels
946  */
947 deprecated
948 AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays_channels(uint8_t **data,
949                                                                       int linesize,
950                                                                       int perms,
951                                                                       int nb_samples,
952                                                                       AVSampleFormat sample_fmt,
953                                                                       int channels,
954                                                                       uint64_t channel_layout);
955 
956 }
957 
958 
959 const uint AVFILTER_CMD_FLAG_ONE  = 1; ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically
960 const uint AVFILTER_CMD_FLAG_FAST = 2; ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)
961 
962 /**
963  * Make the filter instance process a command.
964  * It is recommended to use avfilter_graph_send_command().
965  */
966 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);
967 
968 /** Initialize the filter system. Register all builtin filters. */
969 void avfilter_register_all();
970 
971 static if (FF_API_OLD_FILTER_REGISTER) {
972 /** Uninitialize the filter system. Unregister all filters. */
973 deprecated
974 void avfilter_uninit();
975 }
976 
977 /**
978  * Register a filter. This is only needed if you plan to use
979  * avfilter_get_by_name later to lookup the AVFilter structure by name. A
980  * filter can still by instantiated with avfilter_graph_alloc_filter even if it
981  * is not registered.
982  *
983  * @param filter the filter to register
984  * @return 0 if the registration was successful, a negative value
985  * otherwise
986  */
987 int avfilter_register(AVFilter *filter);
988 
989 /**
990  * Get a filter definition matching the given name.
991  *
992  * @param name the filter name to find
993  * @return     the filter definition, if any matching one is registered.
994  *             NULL if none found.
995  */
996 //#if !FF_API_NOCONST_GET_NAME
997 //const
998 //#endif
999 AVFilter *avfilter_get_by_name(const char *name);
1000 
1001 /**
1002  * Iterate over all registered filters.
1003  * @return If prev is non-NULL, next registered filter after prev or NULL if
1004  * prev is the last filter. If prev is NULL, return the first registered filter.
1005  */
1006 AVFilter *avfilter_next(const AVFilter *prev);
1007 
1008 static if (FF_API_OLD_FILTER_REGISTER) {
1009 /**
1010  * If filter is NULL, returns a pointer to the first registered filter pointer,
1011  * if filter is non-NULL, returns the next pointer after filter.
1012  * If the returned pointer points to NULL, the last registered filter
1013  * was already reached.
1014  * @deprecated use avfilter_next()
1015  */
1016 deprecated
1017 AVFilter **av_filter_next(AVFilter **filter);
1018 }
1019 
1020 static if (FF_API_AVFILTER_OPEN) {
1021 /**
1022  * Create a filter instance.
1023  *
1024  * @param filter_ctx put here a pointer to the created filter context
1025  * on success, NULL on failure
1026  * @param filter    the filter to create an instance of
1027  * @param inst_name Name to give to the new instance. Can be NULL for none.
1028  * @return >= 0 in case of success, a negative error code otherwise
1029  * @deprecated use avfilter_graph_alloc_filter() instead
1030  */
1031 deprecated
1032 int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name);
1033 }
1034 
1035 
1036 static if (FF_API_AVFILTER_INIT_FILTER) {
1037 /**
1038  * Initialize a filter.
1039  *
1040  * @param filter the filter to initialize
1041  * @param args   A string of parameters to use when initializing the filter.
1042  *               The format and meaning of this string varies by filter.
1043  * @param opaque Any extra non-string data needed by the filter. The meaning
1044  *               of this parameter varies by filter.
1045  * @return       zero on success
1046  */
1047 deprecated
1048 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
1049 }
1050 
1051 /**
1052  * Initialize a filter with the supplied parameters.
1053  *
1054  * @param ctx  uninitialized filter context to initialize
1055  * @param args Options to initialize the filter with. This must be a
1056  *             ':'-separated list of options in the 'key=value' form.
1057  *             May be NULL if the options have been set directly using the
1058  *             AVOptions API or there are no options that need to be set.
1059  * @return 0 on success, a negative AVERROR on failure
1060  */
1061 int avfilter_init_str(AVFilterContext *ctx, const char *args);
1062 
1063 /**
1064  * Initialize a filter with the supplied dictionary of options.
1065  *
1066  * @param ctx     uninitialized filter context to initialize
1067  * @param options An AVDictionary filled with options for this filter. On
1068  *                return this parameter will be destroyed and replaced with
1069  *                a dict containing options that were not found. This dictionary
1070  *                must be freed by the caller.
1071  *                May be NULL, then this function is equivalent to
1072  *                avfilter_init_str() with the second parameter set to NULL.
1073  * @return 0 on success, a negative AVERROR on failure
1074  *
1075  * @note This function and avfilter_init_str() do essentially the same thing,
1076  * the difference is in manner in which the options are passed. It is up to the
1077  * calling code to choose whichever is more preferable. The two functions also
1078  * behave differently when some of the provided options are not declared as
1079  * supported by the filter. In such a case, avfilter_init_str() will fail, but
1080  * this function will leave those extra options in the options AVDictionary and
1081  * continue as usual.
1082  */
1083 int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options);
1084 
1085 /**
1086  * Free a filter context. This will also remove the filter from its
1087  * filtergraph's list of filters.
1088  *
1089  * @param filter the filter to free
1090  */
1091 void avfilter_free(AVFilterContext *filter);
1092 
1093 /**
1094  * Insert a filter in the middle of an existing link.
1095  *
1096  * @param link the link into which the filter should be inserted
1097  * @param filt the filter to be inserted
1098  * @param filt_srcpad_idx the input pad on the filter to connect
1099  * @param filt_dstpad_idx the output pad on the filter to connect
1100  * @return     zero on success
1101  */
1102 int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
1103                            uint filt_srcpad_idx, uint filt_dstpad_idx);
1104 
1105 static if (FF_API_AVFILTERBUFFER) {
1106 /**
1107  * Copy the frame properties of src to dst, without copying the actual
1108  * image data.
1109  *
1110  * @return 0 on success, a negative number on error.
1111  */
1112 deprecated
1113 int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src);
1114 
1115 /**
1116  * Copy the frame properties and data pointers of src to dst, without copying
1117  * the actual data.
1118  *
1119  * @return 0 on success, a negative number on error.
1120  */
1121 deprecated
1122 int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src);
1123 }
1124 
1125 /**
1126  * @return AVClass for AVFilterContext.
1127  *
1128  * @see av_opt_find().
1129  */
1130 AVClass *avfilter_get_class();
1131 
1132 struct AVFilterGraphInternal;
1133 
1134 /**
1135  * A function pointer passed to the @ref AVFilterGraph.execute callback to be
1136  * executed multiple times, possibly in parallel.
1137  *
1138  * @param ctx the filter context the job belongs to
1139  * @param arg an opaque parameter passed through from @ref
1140  *            AVFilterGraph.execute
1141  * @param jobnr the index of the job being executed
1142  * @param nb_jobs the total number of jobs
1143  *
1144  * @return 0 on success, a negative AVERROR on error
1145  */
1146 alias avfilter_action_func = int function (AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
1147 
1148 /**
1149  * A function executing multiple jobs, possibly in parallel.
1150  *
1151  * @param ctx the filter context to which the jobs belong
1152  * @param func the function to be called multiple times
1153  * @param arg the argument to be passed to func
1154  * @param ret a nb_jobs-sized array to be filled with return values from each
1155  *            invocation of func
1156  * @param nb_jobs the number of jobs to execute
1157  *
1158  * @return 0 on success, a negative AVERROR on error
1159  */
1160 alias avfilter_execute_func = int function(AVFilterContext *ctx, avfilter_action_func *func,
1161                                     void *arg, int *ret, int nb_jobs);
1162 
1163 struct AVFilterGraph {
1164     const AVClass *av_class;
1165 static if (FF_API_FOO_COUNT) {
1166     deprecated
1167     uint filter_count_unused;
1168 }
1169     AVFilterContext **filters;
1170 static if (!FF_API_FOO_COUNT) {
1171     uint nb_filters;
1172 }
1173 
1174     char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
1175     char *resample_lavr_opts;   ///< libavresample options to use for the auto-inserted resample filters
1176 static if (FF_API_FOO_COUNT) {
1177     uint nb_filters;
1178 }
1179 
1180     /**
1181      * Type of multithreading allowed for filters in this graph. A combination
1182      * of AVFILTER_THREAD_* flags.
1183      *
1184      * May be set by the caller at any point, the setting will apply to all
1185      * filters initialized after that. The default is allowing everything.
1186      *
1187      * When a filter in this graph is initialized, this field is combined using
1188      * bit AND with AVFilterContext.thread_type to get the final mask used for
1189      * determining allowed threading types. I.e. a threading type needs to be
1190      * set in both to be allowed.
1191      */
1192     int thread_type;
1193 
1194     /**
1195      * Maximum number of threads used by filters in this graph. May be set by
1196      * the caller before adding any filters to the filtergraph. Zero (the
1197      * default) means that the number of threads is determined automatically.
1198      */
1199     int nb_threads;
1200 
1201     /**
1202      * Opaque object for libavfilter internal use.
1203      */
1204     AVFilterGraphInternal *internal;
1205 
1206     /**
1207      * Opaque user data. May be set by the caller to an arbitrary value, e.g. to
1208      * be used from callbacks like @ref AVFilterGraph.execute.
1209      * Libavfilter will not touch this field in any way.
1210      */
1211     void *opaque;
1212 
1213     /**
1214      * This callback may be set by the caller immediately after allocating the
1215      * graph and before adding any filters to it, to provide a custom
1216      * multithreading implementation.
1217      *
1218      * If set, filters with slice threading capability will call this callback
1219      * to execute multiple jobs in parallel.
1220      *
1221      * If this field is left unset, libavfilter will use its internal
1222      * implementation, which may or may not be multithreaded depending on the
1223      * platform and build options.
1224      */
1225     avfilter_execute_func *execute;
1226 
1227     char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions
1228 
1229     /**
1230      * Private fields
1231      *
1232      * The following fields are for internal use only.
1233      * Their type, offset, number and semantic can change without notice.
1234      */
1235 
1236     AVFilterLink **sink_links;
1237     int sink_links_count;
1238 
1239     uint disable_auto_convert;
1240 };
1241 
1242 /**
1243  * Allocate a filter graph.
1244  */
1245 AVFilterGraph *avfilter_graph_alloc();
1246 
1247 /**
1248  * Create a new filter instance in a filter graph.
1249  *
1250  * @param graph graph in which the new filter will be used
1251  * @param filter the filter to create an instance of
1252  * @param name Name to give to the new instance (will be copied to
1253  *             AVFilterContext.name). This may be used by the caller to identify
1254  *             different filters, libavfilter itself assigns no semantics to
1255  *             this parameter. May be NULL.
1256  *
1257  * @return the context of the newly created filter instance (note that it is
1258  *         also retrievable directly through AVFilterGraph.filters or with
1259  *         avfilter_graph_get_filter()) on success or NULL on failure.
1260  */
1261 AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph,
1262                                              const AVFilter *filter,
1263                                              const char *name);
1264 
1265 /**
1266  * Get a filter instance identified by instance name from graph.
1267  *
1268  * @param graph filter graph to search through.
1269  * @param name filter instance name (should be unique in the graph).
1270  * @return the pointer to the found filter instance or NULL if it
1271  * cannot be found.
1272  */
1273 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, const char *name);
1274 
1275 static if (FF_API_AVFILTER_OPEN) {
1276 /**
1277  * Add an existing filter instance to a filter graph.
1278  *
1279  * @param graphctx  the filter graph
1280  * @param filter the filter to be added
1281  *
1282  * @deprecated use avfilter_graph_alloc_filter() to allocate a filter in a
1283  * filter graph
1284  */
1285 deprecated
1286 int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
1287 }
1288 
1289 /**
1290  * Create and add a filter instance into an existing graph.
1291  * The filter instance is created from the filter filt and inited
1292  * with the parameters args and opaque.
1293  *
1294  * In case of success put in *filt_ctx the pointer to the created
1295  * filter instance, otherwise set *filt_ctx to NULL.
1296  *
1297  * @param name the instance name to give to the created filter instance
1298  * @param graph_ctx the filter graph
1299  * @return a negative AVERROR error code in case of failure, a non
1300  * negative value otherwise
1301  */
1302 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt,
1303                                  const char *name, const char *args, void *opaque,
1304                                  AVFilterGraph *graph_ctx);
1305 
1306 /**
1307  * Enable or disable automatic format conversion inside the graph.
1308  *
1309  * Note that format conversion can still happen inside explicitly inserted
1310  * scale and aresample filters.
1311  *
1312  * @param flags  any of the AVFILTER_AUTO_CONVERT_* constants
1313  */
1314 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, uint flags);
1315 
1316 enum {
1317     AVFILTER_AUTO_CONVERT_ALL  =  0, /**< all automatic conversions enabled */
1318     AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */
1319 };
1320 
1321 /**
1322  * Check validity and configure all the links and formats in the graph.
1323  *
1324  * @param graphctx the filter graph
1325  * @param log_ctx context used for logging
1326  * @return >= 0 in case of success, a negative AVERROR code otherwise
1327  */
1328 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
1329 
1330 /**
1331  * Free a graph, destroy its links, and set *graph to NULL.
1332  * If *graph is NULL, do nothing.
1333  */
1334 void avfilter_graph_free(AVFilterGraph **graph);
1335 
1336 /**
1337  * A linked-list of the inputs/outputs of the filter chain.
1338  *
1339  * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
1340  * where it is used to communicate open (unlinked) inputs and outputs from and
1341  * to the caller.
1342  * This struct specifies, per each not connected pad contained in the graph, the
1343  * filter context and the pad index required for establishing a link.
1344  */
1345 struct AVFilterInOut {
1346     /** unique name for this input/output in the list */
1347     char *name;
1348 
1349     /** filter context associated to this input/output */
1350     AVFilterContext *filter_ctx;
1351 
1352     /** index of the filt_ctx pad to use for linking */
1353     int pad_idx;
1354 
1355     /** next input/input in the list, NULL if this is the last */
1356     AVFilterInOut *next;
1357 }
1358 
1359 /**
1360  * Allocate a single AVFilterInOut entry.
1361  * Must be freed with avfilter_inout_free().
1362  * @return allocated AVFilterInOut on success, NULL on failure.
1363  */
1364 AVFilterInOut *avfilter_inout_alloc();
1365 
1366 /**
1367  * Free the supplied list of AVFilterInOut and set *inout to NULL.
1368  * If *inout is NULL, do nothing.
1369  */
1370 void avfilter_inout_free(AVFilterInOut **_inout);
1371 
1372 static if (AV_HAVE_INCOMPATIBLE_LIBAV_ABI || !FF_API_OLD_GRAPH_PARSE) {
1373 /**
1374  * Add a graph described by a string to a graph.
1375  *
1376  * @note The caller must provide the lists of inputs and outputs,
1377  * which therefore must be known before calling the function.
1378  *
1379  * @note The inputs parameter describes inputs of the already existing
1380  * part of the graph; i.e. from the point of view of the newly created
1381  * part, they are outputs. Similarly the outputs parameter describes
1382  * outputs of the already existing filters, which are provided as
1383  * inputs to the parsed filters.
1384  *
1385  * @param graph   the filter graph where to link the parsed graph context
1386  * @param filters string to be parsed
1387  * @param inputs  linked list to the inputs of the graph
1388  * @param outputs linked list to the outputs of the graph
1389  * @return zero on success, a negative AVERROR code on error
1390  */
1391 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1392                          AVFilterInOut *inputs, AVFilterInOut *outputs,
1393                          void *log_ctx);
1394 } else {
1395 /**
1396  * Add a graph described by a string to a graph.
1397  *
1398  * @param graph   the filter graph where to link the parsed graph context
1399  * @param filters string to be parsed
1400  * @param inputs  pointer to a linked list to the inputs of the graph, may be NULL.
1401  *                If non-NULL, *inputs is updated to contain the list of open inputs
1402  *                after the parsing, should be freed with avfilter_inout_free().
1403  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1404  *                If non-NULL, *outputs is updated to contain the list of open outputs
1405  *                after the parsing, should be freed with avfilter_inout_free().
1406  * @return non negative on success, a negative AVERROR code on error
1407  * @deprecated Use avfilter_graph_parse_ptr() instead.
1408  */
1409 deprecated
1410 int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
1411                          AVFilterInOut **inputs, AVFilterInOut **outputs,
1412                          void *log_ctx);
1413 }
1414 
1415 /**
1416  * Add a graph described by a string to a graph.
1417  *
1418  * @param graph   the filter graph where to link the parsed graph context
1419  * @param filters string to be parsed
1420  * @param inputs  pointer to a linked list to the inputs of the graph, may be NULL.
1421  *                If non-NULL, *inputs is updated to contain the list of open inputs
1422  *                after the parsing, should be freed with avfilter_inout_free().
1423  * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
1424  *                If non-NULL, *outputs is updated to contain the list of open outputs
1425  *                after the parsing, should be freed with avfilter_inout_free().
1426  * @return non negative on success, a negative AVERROR code on error
1427  */
1428 int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
1429                              AVFilterInOut **inputs, AVFilterInOut **outputs,
1430                              void *log_ctx);
1431 
1432 /**
1433  * Add a graph described by a string to a graph.
1434  *
1435  * @param[in]  graph   the filter graph where to link the parsed graph context
1436  * @param[in]  filters string to be parsed
1437  * @param[out] inputs  a linked list of all free (unlinked) inputs of the
1438  *                     parsed graph will be returned here. It is to be freed
1439  *                     by the caller using avfilter_inout_free().
1440  * @param[out] outputs a linked list of all free (unlinked) outputs of the
1441  *                     parsed graph will be returned here. It is to be freed by the
1442  *                     caller using avfilter_inout_free().
1443  * @return zero on success, a negative AVERROR code on error
1444  *
1445  * @note This function returns the inputs and outputs that are left
1446  * unlinked after parsing the graph and the caller then deals with
1447  * them.
1448  * @note This function makes no reference whatsoever to already
1449  * existing parts of the graph and the inputs parameter will on return
1450  * contain inputs of the newly parsed part of the graph.  Analogously
1451  * the outputs parameter will contain outputs of the newly created
1452  * filters.
1453  */
1454 int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
1455                           AVFilterInOut **inputs,
1456                           AVFilterInOut **outputs);
1457 
1458 /**
1459  * Send a command to one or more filter instances.
1460  *
1461  * @param graph  the filter graph
1462  * @param target the filter(s) to which the command should be sent
1463  *               "all" sends to all filters
1464  *               otherwise it can be a filter or filter instance name
1465  *               which will send the command to all matching filters.
1466  * @param cmd    the command to send, for handling simplicity all commands must be alphanumeric only
1467  * @param arg    the argument for the command
1468  * @param res    a buffer with size res_size where the filter(s) can return a response.
1469  *
1470  * @returns >=0 on success otherwise an error code.
1471  *              AVERROR(ENOSYS) on unsupported commands
1472  */
1473 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
1474 
1475 /**
1476  * Queue a command for one or more filter instances.
1477  *
1478  * @param graph  the filter graph
1479  * @param target the filter(s) to which the command should be sent
1480  *               "all" sends to all filters
1481  *               otherwise it can be a filter or filter instance name
1482  *               which will send the command to all matching filters.
1483  * @param cmd    the command to sent, for handling simplicity all commands must be alphanumeric only
1484  * @param arg    the argument for the command
1485  * @param ts     time at which the command should be sent to the filter
1486  *
1487  * @note As this executes commands after this function returns, no return code
1488  *       from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
1489  */
1490 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
1491 
1492 
1493 /**
1494  * Dump a graph into a human-readable string representation.
1495  *
1496  * @param graph    the graph to dump
1497  * @param options  formatting options; currently ignored
1498  * @return  a string, or NULL in case of memory allocation failure;
1499  *          the string must be freed using av_free
1500  */
1501 char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
1502 
1503 /**
1504  * Request a frame on the oldest sink link.
1505  *
1506  * If the request returns AVERROR_EOF, try the next.
1507  *
1508  * Note that this function is not meant to be the sole scheduling mechanism
1509  * of a filtergraph, only a convenience function to help drain a filtergraph
1510  * in a balanced way under normal circumstances.
1511  *
1512  * Also note that AVERROR_EOF does not mean that frames did not arrive on
1513  * some of the sinks during the process.
1514  * When there are multiple sink links, in case the requested link
1515  * returns an EOF, this may cause a filter to flush pending frames
1516  * which are sent to another sink link, although unrequested.
1517  *
1518  * @return  the return value of ff_request_frame(),
1519  *          or AVERROR_EOF if all links returned AVERROR_EOF
1520  */
1521 int avfilter_graph_request_oldest(AVFilterGraph *graph);
1522 
1523 /**
1524  * @}
1525  */
1526 
1527 //#endif /* AVFILTER_AVFILTER_H */