FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
internal.h
Go to the documentation of this file.
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 "thread.h"
32 #include "version.h"
33 #include "video.h"
34 #include "libavcodec/avcodec.h"
35 
36 #if FF_API_AVFILTERBUFFER
37 #define POOL_SIZE 32
38 typedef struct AVFilterPool {
39  AVFilterBufferRef *pic[POOL_SIZE];
40  int count;
41  int refcount;
42  int draining;
43 } AVFilterPool;
44 #endif
45 
46 typedef struct AVFilterCommand {
47  double time; ///< time expressed in seconds
48  char *command; ///< command
49  char *arg; ///< optional argument for the command
50  int flags;
53 
54 /**
55  * Update the position of a link in the age heap.
56  */
58 
59 #if !FF_API_AVFILTERPAD_PUBLIC
60 /**
61  * A filter pad used for either input or output.
62  */
63 struct AVFilterPad {
64  /**
65  * Pad name. The name is unique among inputs and among outputs, but an
66  * input may have the same name as an output. This may be NULL if this
67  * pad has no need to ever be referenced by name.
68  */
69  const char *name;
70 
71  /**
72  * AVFilterPad type.
73  */
75 
76  /**
77  * Callback function to get a video buffer. If NULL, the filter system will
78  * use ff_default_get_video_buffer().
79  *
80  * Input video pads only.
81  */
82  AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h);
83 
84  /**
85  * Callback function to get an audio buffer. If NULL, the filter system will
86  * use ff_default_get_audio_buffer().
87  *
88  * Input audio pads only.
89  */
90  AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples);
91 
92  /**
93  * Filtering callback. This is where a filter receives a frame with
94  * audio/video data and should do its processing.
95  *
96  * Input pads only.
97  *
98  * @return >= 0 on success, a negative AVERROR on error. This function
99  * must ensure that samplesref is properly unreferenced on error if it
100  * hasn't been passed on to another filter.
101  */
103 
104  /**
105  * Frame poll callback. This returns the number of immediately available
106  * samples. It should return a positive value if the next request_frame()
107  * is guaranteed to return one frame (with no delay).
108  *
109  * Defaults to just calling the source poll_frame() method.
110  *
111  * Output pads only.
112  */
113  int (*poll_frame)(AVFilterLink *link);
114 
115  /**
116  * Frame request callback. A call to this should result in at least one
117  * frame being output over the given link. This should return zero on
118  * success, and another value on error.
119  *
120  * Output pads only.
121  */
123 
124  /**
125  * Link configuration callback.
126  *
127  * For output pads, this should set the link properties such as
128  * width/height. This should NOT set the format property - that is
129  * negotiated between filters by the filter system using the
130  * query_formats() callback before this function is called.
131  *
132  * For input pads, this should check the properties of the link, and update
133  * the filter's internal state as necessary.
134  *
135  * For both input and output filters, this should return zero on success,
136  * and another value on error.
137  */
138  int (*config_props)(AVFilterLink *link);
139 
140  /**
141  * The filter expects a fifo to be inserted on its input link,
142  * typically because it has a delay.
143  *
144  * input pads only.
145  */
147 
148  /**
149  * The filter expects writable frames from its input link,
150  * duplicating data buffers if needed.
151  *
152  * input pads only.
153  */
155 };
156 #endif
157 
159  void *thread;
161 };
162 
165 };
166 
167 #if FF_API_AVFILTERBUFFER
168 /** default handler for freeing audio/video buffer when there are no references left */
169 void ff_avfilter_default_free_buffer(AVFilterBuffer *buf);
170 #endif
171 
172 /** Tell is a format is contained in the provided list terminated by -1. */
173 int ff_fmt_is_in(int fmt, const int *fmts);
174 
175 /* Functions to parse audio format arguments */
176 
177 /**
178  * Parse a pixel format.
179  *
180  * @param ret pixel format pointer to where the value should be written
181  * @param arg string to parse
182  * @param log_ctx log context
183  * @return >= 0 in case of success, a negative AVERROR code on error
184  */
185 int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx);
186 
187 /**
188  * Parse a sample rate.
189  *
190  * @param ret unsigned integer pointer to where the value should be written
191  * @param arg string to parse
192  * @param log_ctx log context
193  * @return >= 0 in case of success, a negative AVERROR code on error
194  */
195 int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx);
196 
197 /**
198  * Parse a time base.
199  *
200  * @param ret unsigned AVRational pointer to where the value should be written
201  * @param arg string to parse
202  * @param log_ctx log context
203  * @return >= 0 in case of success, a negative AVERROR code on error
204  */
205 int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx);
206 
207 /**
208  * Parse a sample format name or a corresponding integer representation.
209  *
210  * @param ret integer pointer to where the value should be written
211  * @param arg string to parse
212  * @param log_ctx log context
213  * @return >= 0 in case of success, a negative AVERROR code on error
214  */
215 int ff_parse_sample_format(int *ret, const char *arg, void *log_ctx);
216 
217 /**
218  * Parse a channel layout or a corresponding integer representation.
219  *
220  * @param ret 64bit integer pointer to where the value should be written.
221  * @param nret integer pointer to the number of channels;
222  * if not NULL, then unknown channel layouts are accepted
223  * @param arg string to parse
224  * @param log_ctx log context
225  * @return >= 0 in case of success, a negative AVERROR code on error
226  */
227 int ff_parse_channel_layout(int64_t *ret, int *nret, const char *arg,
228  void *log_ctx);
229 
230 void ff_update_link_current_pts(AVFilterLink *link, int64_t pts);
231 
233 
234 /* misc trace functions */
235 
236 /* #define FF_AVFILTER_TRACE */
237 
238 #ifdef FF_AVFILTER_TRACE
239 # define ff_tlog(pctx, ...) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__)
240 #else
241 # define ff_tlog(pctx, ...) do { if (0) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
242 #endif
243 
244 #define FF_TPRINTF_START(ctx, func) ff_tlog(NULL, "%-16s: ", #func)
245 
246 char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms);
247 
248 void ff_tlog_ref(void *ctx, AVFrame *ref, int end);
249 
250 void ff_tlog_link(void *ctx, AVFilterLink *link, int end);
251 
252 /**
253  * Insert a new pad.
254  *
255  * @param idx Insertion point. Pad is inserted at the end if this point
256  * is beyond the end of the list of pads.
257  * @param count Pointer to the number of pads in the list
258  * @param padidx_off Offset within an AVFilterLink structure to the element
259  * to increment when inserting a new pad causes link
260  * numbering to change
261  * @param pads Pointer to the pointer to the beginning of the list of pads
262  * @param links Pointer to the pointer to the beginning of the list of links
263  * @param newpad The new pad to add. A copy is made when adding.
264  * @return >= 0 in case of success, a negative AVERROR code on error
265  */
266 int ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
267  AVFilterPad **pads, AVFilterLink ***links,
268  AVFilterPad *newpad);
269 
270 /** Insert a new input pad for the filter. */
271 static inline int ff_insert_inpad(AVFilterContext *f, unsigned index,
272  AVFilterPad *p)
273 {
274  int ret = ff_insert_pad(index, &f->nb_inputs, offsetof(AVFilterLink, dstpad),
275  &f->input_pads, &f->inputs, p);
276 #if FF_API_FOO_COUNT
278  f->input_count = f->nb_inputs;
280 #endif
281  return ret;
282 }
283 
284 /** Insert a new output pad for the filter. */
285 static inline int ff_insert_outpad(AVFilterContext *f, unsigned index,
286  AVFilterPad *p)
287 {
288  int ret = ff_insert_pad(index, &f->nb_outputs, offsetof(AVFilterLink, srcpad),
289  &f->output_pads, &f->outputs, p);
290 #if FF_API_FOO_COUNT
292  f->output_count = f->nb_outputs;
294 #endif
295  return ret;
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 the filter_frame() function will be called
324  * at least once before ff_request_frame() returns
325  *
326  * @param link the input link
327  * @return zero on success
328  * AVERROR_EOF on end of file
329  * AVERROR(EAGAIN) if the previous filter cannot output a frame
330  * currently and can neither guarantee that EOF has been reached.
331  */
332 int ff_request_frame(AVFilterLink *link);
333 
334 #define AVFILTER_DEFINE_CLASS(fname) \
335  static const AVClass fname##_class = { \
336  .class_name = #fname, \
337  .item_name = av_default_item_name, \
338  .option = fname##_options, \
339  .version = LIBAVUTIL_VERSION_INT, \
340  .category = AV_CLASS_CATEGORY_FILTER, \
341  }
342 
343 /**
344  * Find the index of a link.
345  *
346  * I.e. find i such that link == ctx->(in|out)puts[i]
347  */
348 #define FF_INLINK_IDX(link) ((int)((link)->dstpad - (link)->dst->input_pads))
349 #define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
350 
351 /**
352  * Send a frame of data to the next filter.
353  *
354  * @param link the output link over which the data is being sent
355  * @param frame a reference to the buffer of data being sent. The
356  * receiving filter will free this reference when it no longer
357  * needs it or pass it on to the next filter.
358  *
359  * @return >= 0 on success, a negative AVERROR on error. The receiving filter
360  * is responsible for unreferencing frame in case of error.
361  */
363 
364 /**
365  * Flags for AVFilterLink.flags.
366  */
367 enum {
368 
369  /**
370  * Frame requests may need to loop in order to be fulfilled.
371  * A filter must set this flags on an output link if it may return 0 in
372  * request_frame() without filtering a frame.
373  */
375 
376 };
377 
378 /**
379  * Allocate a new filter context and return it.
380  *
381  * @param filter what filter to create an instance of
382  * @param inst_name name to give to the new filter context
383  *
384  * @return newly created filter context or NULL on failure
385  */
386 AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name);
387 
388 /**
389  * Remove a filter from a graph;
390  */
392 
393 /**
394  * Normalize the qscale factor
395  * FIXME the H264 qscale is a log based scale, mpeg1/2 is not, the code below
396  * cannot be optimal
397  */
398 static inline int ff_norm_qscale(int qscale, int type)
399 {
400  switch (type) {
401  case FF_QSCALE_TYPE_MPEG1: return qscale;
402  case FF_QSCALE_TYPE_MPEG2: return qscale >> 1;
403  case FF_QSCALE_TYPE_H264: return qscale >> 2;
404  case FF_QSCALE_TYPE_VP56: return (63 - qscale + 2) >> 2;
405  }
406  return qscale;
407 }
408 
409 #endif /* AVFILTER_INTERNAL_H */
int(* poll_frame)(AVFilterLink *link)
Frame poll callback.
Definition: internal.h:113
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1158
const char * fmt
Definition: avisynth_c.h:632
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:99
Main libavfilter public API header.
Libavfilter version macros.
enum AVMediaType type
AVFilterPad type.
Definition: internal.h:74
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:1195
#define FF_QSCALE_TYPE_H264
Definition: avcodec.h:1197
const char * name
Pad name.
Definition: internal.h:69
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:641
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:647
int(* request_frame)(AVFilterLink *link)
Frame request callback.
Definition: internal.h:122
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int ff_fmt_is_in(int fmt, const int *fmts)
Tell is a format is contained in the provided list terminated by -1.
Definition: formats.c:254
int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx)
Parse a pixel format.
Definition: formats.c:583
static AVFrame * frame
void ff_update_link_current_pts(AVFilterLink *link, int64_t pts)
Definition: avfilter.c:450
A filter pad used for either input or output.
Definition: internal.h:63
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:640
unsigned nb_outputs
number of output pads
Definition: avfilter.h:652
int(* filter_frame)(AVFilterLink *link, AVFrame *frame)
Filtering callback.
Definition: internal.h:102
int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx)
Parse a time base.
Definition: formats.c:613
const char * arg
Definition: jacosubdec.c:66
GLsizei count
Definition: opengl_enc.c:109
Libavcodec external API header.
common internal API header
unsigned nb_inputs
number of input pads
Definition: avfilter.h:645
struct AVFilterCommand * next
Definition: internal.h:51
void ff_command_queue_pop(AVFilterContext *filter)
Definition: avfilter.c:90
int needs_writable
The filter expects writable frames from its input link, duplicating data buffers if needed...
Definition: internal.h:154
Frame requests may need to loop in order to be fulfilled.
Definition: internal.h:374
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:1168
char * ff_get_ref_perms_string(char *buf, size_t buf_size, int perms)
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:553
GLint GLenum type
Definition: opengl_enc.c:105
Filter definition.
Definition: avfilter.h:470
int index
Definition: gxfenc.c:89
rational number numerator/denominator
Definition: rational.h:43
AVMediaType
Definition: avutil.h:191
#define FF_QSCALE_TYPE_VP56
Definition: avcodec.h:1198
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:648
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:398
static int64_t pts
Global timestamp for the audio frames.
static void filter(MpegAudioContext *s, int ch, const short *samples, int incr)
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:79
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:636
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:598
avfilter_execute_func * execute
Definition: internal.h:164
void ff_tlog_ref(void *ctx, AVFrame *ref, int end)
Definition: avfilter.c:45
avfilter_execute_func * thread_execute
Definition: internal.h:160
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:80
void ff_tlog_link(void *ctx, AVFilterLink *link, int end)
Definition: avfilter.c:319
#define FF_QSCALE_TYPE_MPEG2
Definition: avcodec.h:1196
int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx)
Parse a sample rate.
Definition: formats.c:624
An instance of a filter.
Definition: avfilter.h:633
int ff_poll_frame(AVFilterLink *link)
Poll a frame from the filter chain.
Definition: avfilter.c:374
AVFilterContext * ff_filter_alloc(const AVFilter *filter, const char *inst_name)
Allocate a new filter context and return it.
Definition: avfilter.c:622
int(* config_props)(AVFilterLink *link)
Link configuration callback.
Definition: internal.h:138
double time
time expressed in seconds
Definition: internal.h:47
int needs_fifo
The filter expects a fifo to be inserted on its input link, typically because it has a delay...
Definition: internal.h:146
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:343
static int ff_insert_outpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new output pad for the filter.
Definition: internal.h:285
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
char * command
command
Definition: internal.h:48
static int ff_insert_inpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new input pad for the filter.
Definition: internal.h:271
char * arg
optional argument for the command
Definition: internal.h:49