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internal.h
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVFILTER_INTERNAL_H
20 #define AVFILTER_INTERNAL_H
21 
22 /**
23  * @file
24  * internal API functions
25  */
26 
27 #include "libavutil/internal.h"
28 #include "avfilter.h"
29 #include "avfiltergraph.h"
30 #include "formats.h"
31 #include "framepool.h"
32 #include "thread.h"
33 #include "version.h"
34 #include "video.h"
35 #include "libavcodec/avcodec.h"
36 
37 typedef struct AVFilterCommand {
38  double time; ///< time expressed in seconds
39  char *command; ///< command
40  char *arg; ///< optional argument for the command
41  int flags;
44 
45 /**
46  * Update the position of a link in the age heap.
47  */
49 
50 /**
51  * A filter pad used for either input or output.
52  */
53 struct AVFilterPad {
54  /**
55  * Pad name. The name is unique among inputs and among outputs, but an
56  * input may have the same name as an output. This may be NULL if this
57  * pad has no need to ever be referenced by name.
58  */
59  const char *name;
60 
61  /**
62  * AVFilterPad type.
63  */
65 
66  /**
67  * Callback function to get a video buffer. If NULL, the filter system will
68  * use ff_default_get_video_buffer().
69  *
70  * Input video pads only.
71  */
72  AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h);
73 
74  /**
75  * Callback function to get an audio buffer. If NULL, the filter system will
76  * use ff_default_get_audio_buffer().
77  *
78  * Input audio pads only.
79  */
80  AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples);
81 
82  /**
83  * Filtering callback. This is where a filter receives a frame with
84  * audio/video data and should do its processing.
85  *
86  * Input pads only.
87  *
88  * @return >= 0 on success, a negative AVERROR on error. This function
89  * must ensure that frame is properly unreferenced on error if it
90  * hasn't been passed on to another filter.
91  */
93 
94  /**
95  * Frame poll callback. This returns the number of immediately available
96  * samples. It should return a positive value if the next request_frame()
97  * is guaranteed to return one frame (with no delay).
98  *
99  * Defaults to just calling the source poll_frame() method.
100  *
101  * Output pads only.
102  */
103  int (*poll_frame)(AVFilterLink *link);
104 
105  /**
106  * Frame request callback. A call to this should result in some progress
107  * towards producing output over the given link. This should return zero
108  * on success, and another value on error.
109  *
110  * Output pads only.
111  */
113 
114  /**
115  * Link configuration callback.
116  *
117  * For output pads, this should set the link properties such as
118  * width/height. This should NOT set the format property - that is
119  * negotiated between filters by the filter system using the
120  * query_formats() callback before this function is called.
121  *
122  * For input pads, this should check the properties of the link, and update
123  * the filter's internal state as necessary.
124  *
125  * For both input and output filters, this should return zero on success,
126  * and another value on error.
127  */
128  int (*config_props)(AVFilterLink *link);
129 
130  /**
131  * The filter expects a fifo to be inserted on its input link,
132  * typically because it has a delay.
133  *
134  * input pads only.
135  */
137 
138  /**
139  * The filter expects writable frames from its input link,
140  * duplicating data buffers if needed.
141  *
142  * input pads only.
143  */
145 };
146 
148  void *thread;
150 };
151 
154 };
155 
156 /**
157  * Tell if an integer is contained in the provided -1-terminated list of integers.
158  * This is useful for determining (for instance) if an AVPixelFormat is in an
159  * array of supported formats.
160  *
161  * @param fmt provided format
162  * @param fmts -1-terminated list of formats
163  * @return 1 if present, 0 if absent
164  */
165 int ff_fmt_is_in(int fmt, const int *fmts);
166 
167 /* Functions to parse audio format arguments */
168 
169 /**
170  * Parse a pixel format.
171  *
172  * @param ret pixel format pointer to where the value should be written
173  * @param arg string to parse
174  * @param log_ctx log context
175  * @return >= 0 in case of success, a negative AVERROR code on error
176  */
178 int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx);
179 
180 /**
181  * Parse a sample rate.
182  *
183  * @param ret unsigned integer pointer to where the value should be written
184  * @param arg string to parse
185  * @param log_ctx log context
186  * @return >= 0 in case of success, a negative AVERROR code on error
187  */
189 int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx);
190 
191 /**
192  * Parse a time base.
193  *
194  * @param ret unsigned AVRational pointer to where the value should be written
195  * @param arg string to parse
196  * @param log_ctx log context
197  * @return >= 0 in case of success, a negative AVERROR code on error
198  */
200 int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx);
201 
202 /**
203  * Parse a sample format name or a corresponding integer representation.
204  *
205  * @param ret integer pointer to where the value should be written
206  * @param arg string to parse
207  * @param log_ctx log context
208  * @return >= 0 in case of success, a negative AVERROR code on error
209  */
211 int ff_parse_sample_format(int *ret, const char *arg, void *log_ctx);
212 
213 /**
214  * Parse a channel layout or a corresponding integer representation.
215  *
216  * @param ret 64bit integer pointer to where the value should be written.
217  * @param nret integer pointer to the number of channels;
218  * if not NULL, then unknown channel layouts are accepted
219  * @param arg string to parse
220  * @param log_ctx log context
221  * @return >= 0 in case of success, a negative AVERROR code on error
222  */
224 int ff_parse_channel_layout(int64_t *ret, int *nret, const char *arg,
225  void *log_ctx);
226 
227 void ff_update_link_current_pts(AVFilterLink *link, int64_t pts);
228 
229 /**
230  * Set the status field of a link from the source filter.
231  * The pts should reflect the timestamp of the status change,
232  * in link time base and relative to the frames timeline.
233  * In particular, for AVERROR_EOF, it should reflect the
234  * end time of the last frame.
235  */
236 void ff_avfilter_link_set_in_status(AVFilterLink *link, int status, int64_t pts);
237 
238 /**
239  * Set the status field of a link from the destination filter.
240  * The pts should probably be left unset (AV_NOPTS_VALUE).
241  */
242 void ff_avfilter_link_set_out_status(AVFilterLink *link, int status, int64_t pts);
243 
245 
246 /* misc trace functions */
247 
248 /* #define FF_AVFILTER_TRACE */
249 
250 #ifdef FF_AVFILTER_TRACE
251 # define ff_tlog(pctx, ...) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__)
252 #else
253 # define ff_tlog(pctx, ...) do { if (0) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
254 #endif
255 
256 #define FF_TPRINTF_START(ctx, func) ff_tlog(NULL, "%-16s: ", #func)
257 
258 char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms);
259 
260 void ff_tlog_ref(void *ctx, AVFrame *ref, int end);
261 
262 void ff_tlog_link(void *ctx, AVFilterLink *link, int end);
263 
264 /**
265  * Insert a new pad.
266  *
267  * @param idx Insertion point. Pad is inserted at the end if this point
268  * is beyond the end of the list of pads.
269  * @param count Pointer to the number of pads in the list
270  * @param padidx_off Offset within an AVFilterLink structure to the element
271  * to increment when inserting a new pad causes link
272  * numbering to change
273  * @param pads Pointer to the pointer to the beginning of the list of pads
274  * @param links Pointer to the pointer to the beginning of the list of links
275  * @param newpad The new pad to add. A copy is made when adding.
276  * @return >= 0 in case of success, a negative AVERROR code on error
277  */
278 int ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
279  AVFilterPad **pads, AVFilterLink ***links,
280  AVFilterPad *newpad);
281 
282 /** Insert a new input pad for the filter. */
283 static inline int ff_insert_inpad(AVFilterContext *f, unsigned index,
284  AVFilterPad *p)
285 {
286  return ff_insert_pad(index, &f->nb_inputs, offsetof(AVFilterLink, dstpad),
287  &f->input_pads, &f->inputs, p);
288 }
289 
290 /** Insert a new output pad for the filter. */
291 static inline int ff_insert_outpad(AVFilterContext *f, unsigned index,
292  AVFilterPad *p)
293 {
294  return ff_insert_pad(index, &f->nb_outputs, offsetof(AVFilterLink, srcpad),
295  &f->output_pads, &f->outputs, p);
296 }
297 
298 /**
299  * Poll a frame from the filter chain.
300  *
301  * @param link the input link
302  * @return the number of immediately available frames, a negative
303  * number in case of error
304  */
305 int ff_poll_frame(AVFilterLink *link);
306 
307 /**
308  * Request an input frame from the filter at the other end of the link.
309  *
310  * The input filter may pass the request on to its inputs, fulfill the
311  * request from an internal buffer or any other means specific to its function.
312  *
313  * When the end of a stream is reached AVERROR_EOF is returned and no further
314  * frames are returned after that.
315  *
316  * When a filter is unable to output a frame for example due to its sources
317  * being unable to do so or because it depends on external means pushing data
318  * into it then AVERROR(EAGAIN) is returned.
319  * It is important that a AVERROR(EAGAIN) return is returned all the way to the
320  * caller (generally eventually a user application) as this step may (but does
321  * not have to be) necessary to provide the input with the next frame.
322  *
323  * If a request is successful then some progress has been made towards
324  * providing a frame on the link (through ff_filter_frame()). A filter that
325  * needs several frames to produce one is allowed to return success if one
326  * more frame has been processed but no output has been produced yet. A
327  * filter is also allowed to simply forward a success return value.
328  *
329  * @param link the input link
330  * @return zero on success
331  * AVERROR_EOF on end of file
332  * AVERROR(EAGAIN) if the previous filter cannot output a frame
333  * currently and can neither guarantee that EOF has been reached.
334  */
335 int ff_request_frame(AVFilterLink *link);
336 
338 
339 #define AVFILTER_DEFINE_CLASS(fname) \
340  static const AVClass fname##_class = { \
341  .class_name = #fname, \
342  .item_name = av_default_item_name, \
343  .option = fname##_options, \
344  .version = LIBAVUTIL_VERSION_INT, \
345  .category = AV_CLASS_CATEGORY_FILTER, \
346  }
347 
348 /**
349  * Find the index of a link.
350  *
351  * I.e. find i such that link == ctx->(in|out)puts[i]
352  */
353 #define FF_INLINK_IDX(link) ((int)((link)->dstpad - (link)->dst->input_pads))
354 #define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
355 
356 /**
357  * Send a frame of data to the next filter.
358  *
359  * @param link the output link over which the data is being sent
360  * @param frame a reference to the buffer of data being sent. The
361  * receiving filter will free this reference when it no longer
362  * needs it or pass it on to the next filter.
363  *
364  * @return >= 0 on success, a negative AVERROR on error. The receiving filter
365  * is responsible for unreferencing frame in case of error.
366  */
368 
369 /**
370  * Allocate a new filter context and return it.
371  *
372  * @param filter what filter to create an instance of
373  * @param inst_name name to give to the new filter context
374  *
375  * @return newly created filter context or NULL on failure
376  */
377 AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name);
378 
379 /**
380  * Remove a filter from a graph;
381  */
383 
384 /**
385  * Run one round of processing on a filter graph.
386  */
388 
389 /**
390  * Normalize the qscale factor
391  * FIXME the H264 qscale is a log based scale, mpeg1/2 is not, the code below
392  * cannot be optimal
393  */
394 static inline int ff_norm_qscale(int qscale, int type)
395 {
396  switch (type) {
397  case FF_QSCALE_TYPE_MPEG1: return qscale;
398  case FF_QSCALE_TYPE_MPEG2: return qscale >> 1;
399  case FF_QSCALE_TYPE_H264: return qscale >> 2;
400  case FF_QSCALE_TYPE_VP56: return (63 - qscale + 2) >> 2;
401  }
402  return qscale;
403 }
404 
405 /**
406  * Get number of threads for current filter instance.
407  * This number is always same or less than graph->nb_threads.
408  */
410 
411 #endif /* AVFILTER_INTERNAL_H */
int(* poll_frame)(AVFilterLink *link)
Frame poll callback.
Definition: internal.h:103
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1189
const char * fmt
Definition: avisynth_c.h:769
int ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off, AVFilterPad **pads, AVFilterLink ***links, AVFilterPad *newpad)
Insert a new pad.
Definition: avfilter.c:101
Main libavfilter public API header.
Libavfilter version macros.
enum AVMediaType type
AVFilterPad type.
Definition: internal.h:64
void ff_avfilter_graph_update_heap(AVFilterGraph *graph, AVFilterLink *link)
Update the position of a link in the age heap.
#define FF_QSCALE_TYPE_MPEG1
Definition: avcodec.h:1344
#define FF_QSCALE_TYPE_H264
Definition: avcodec.h:1346
const char * name
Pad name.
Definition: internal.h:59
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:315
void ff_avfilter_link_set_in_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
Definition: avfilter.c:183
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:318
int(* request_frame)(AVFilterLink *link)
Frame request callback.
Definition: internal.h:112
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int ff_fmt_is_in(int fmt, const int *fmts)
Tell if an integer is contained in the provided -1-terminated list of integers.
Definition: formats.c:254
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, uint8_t clip)
Definition: cfhd.c:80
static AVFrame * frame
int ff_filter_graph_run_once(AVFilterGraph *graph)
Run one round of processing on a filter graph.
void ff_update_link_current_pts(AVFilterLink *link, int64_t pts)
Definition: avfilter.c:481
A filter pad used for either input or output.
Definition: internal.h:53
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:314
int ff_request_frame_to_filter(AVFilterLink *link)
Definition: avfilter.c:380
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:786
unsigned nb_outputs
number of output pads
Definition: avfilter.h:320
int(* filter_frame)(AVFilterLink *link, AVFrame *frame)
Filtering callback.
Definition: internal.h:92
const char * arg
Definition: jacosubdec.c:66
GLsizei count
Definition: opengl_enc.c:109
common internal API header
av_warn_unused_result int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx)
Parse a pixel format.
Definition: formats.c:609
unsigned nb_inputs
number of input pads
Definition: avfilter.h:316
struct AVFilterCommand * next
Definition: internal.h:42
void ff_command_queue_pop(AVFilterContext *filter)
Definition: avfilter.c:92
AVFormatContext * ctx
Definition: movenc.c:48
int needs_writable
The filter expects writable frames from its input link, duplicating data buffers if needed...
Definition: internal.h:144
int( avfilter_execute_func)(AVFilterContext *ctx, avfilter_action_func *func, void *arg, int *ret, int nb_jobs)
A function executing multiple jobs, possibly in parallel.
Definition: avfilter.h:783
char * ff_get_ref_perms_string(char *buf, size_t buf_size, int perms)
Libavcodec external API header.
av_warn_unused_result int ff_parse_channel_layout(int64_t *ret, int *nret, const char *arg, void *log_ctx)
Parse a channel layout or a corresponding integer representation.
Definition: formats.c:662
void ff_filter_graph_remove_filter(AVFilterGraph *graph, AVFilterContext *filter)
Remove a filter from a graph;.
Definition: avfiltergraph.c:94
void * buf
Definition: avisynth_c.h:690
void ff_avfilter_link_set_out_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the destination filter.
Definition: avfilter.c:188
GLint GLenum type
Definition: opengl_enc.c:105
Filter definition.
Definition: avfilter.h:144
int index
Definition: gxfenc.c:89
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVMediaType
Definition: avutil.h:193
#define FF_QSCALE_TYPE_VP56
Definition: avcodec.h:1347
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:319
static int ff_norm_qscale(int qscale, int type)
Normalize the qscale factor FIXME the H264 qscale is a log based scale, mpeg1/2 is not...
Definition: internal.h:394
static int64_t pts
Global timestamp for the audio frames.
#define av_warn_unused_result
Definition: attributes.h:56
av_warn_unused_result int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx)
Parse a time base.
Definition: formats.c:639
av_warn_unused_result int ff_parse_sample_format(int *ret, const char *arg, void *log_ctx)
Parse a sample format name or a corresponding integer representation.
Definition: formats.c:624
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
av_warn_unused_result int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx)
Parse a sample rate.
Definition: formats.c:650
avfilter_execute_func * execute
Definition: internal.h:153
void ff_tlog_ref(void *ctx, AVFrame *ref, int end)
Definition: avfilter.c:47
avfilter_execute_func * thread_execute
Definition: internal.h:149
void ff_tlog_link(void *ctx, AVFilterLink *link, int end)
Definition: avfilter.c:345
#define FF_QSCALE_TYPE_MPEG2
Definition: avcodec.h:1345
An instance of a filter.
Definition: avfilter.h:307
int ff_poll_frame(AVFilterLink *link)
Poll a frame from the filter chain.
Definition: avfilter.c:405
AVFilterContext * ff_filter_alloc(const AVFilter *filter, const char *inst_name)
Allocate a new filter context and return it.
Definition: avfilter.c:647
int(* config_props)(AVFilterLink *link)
Link configuration callback.
Definition: internal.h:128
double time
time expressed in seconds
Definition: internal.h:38
int needs_fifo
The filter expects a fifo to be inserted on its input link, typically because it has a delay...
Definition: internal.h:136
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:369
static int ff_insert_outpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new output pad for the filter.
Definition: internal.h:291
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
char * command
command
Definition: internal.h:39
static int ff_insert_inpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new input pad for the filter.
Definition: internal.h:283
char * arg
optional argument for the command
Definition: internal.h:40