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 #define POOL_SIZE 32
37 typedef struct AVFilterPool {
38  AVFilterBufferRef *pic[POOL_SIZE];
39  int count;
40  int refcount;
41  int draining;
42 } AVFilterPool;
43 
44 typedef struct AVFilterCommand {
45  double time; ///< time expressed in seconds
46  char *command; ///< command
47  char *arg; ///< optional argument for the command
48  int flags;
51 
52 /**
53  * Update the position of a link in the age heap.
54  */
56 
57 #if !FF_API_AVFILTERPAD_PUBLIC
58 /**
59  * A filter pad used for either input or output.
60  */
61 struct AVFilterPad {
62  /**
63  * Pad name. The name is unique among inputs and among outputs, but an
64  * input may have the same name as an output. This may be NULL if this
65  * pad has no need to ever be referenced by name.
66  */
67  const char *name;
68 
69  /**
70  * AVFilterPad type.
71  */
73 
74  /**
75  * Callback function to get a video buffer. If NULL, the filter system will
76  * use ff_default_get_video_buffer().
77  *
78  * Input video pads only.
79  */
80  AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h);
81 
82  /**
83  * Callback function to get an audio buffer. If NULL, the filter system will
84  * use ff_default_get_audio_buffer().
85  *
86  * Input audio pads only.
87  */
88  AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples);
89 
90  /**
91  * Filtering callback. This is where a filter receives a frame with
92  * audio/video data and should do its processing.
93  *
94  * Input pads only.
95  *
96  * @return >= 0 on success, a negative AVERROR on error. This function
97  * must ensure that samplesref is properly unreferenced on error if it
98  * hasn't been passed on to another filter.
99  */
101 
102  /**
103  * Frame poll callback. This returns the number of immediately available
104  * samples. It should return a positive value if the next request_frame()
105  * is guaranteed to return one frame (with no delay).
106  *
107  * Defaults to just calling the source poll_frame() method.
108  *
109  * Output pads only.
110  */
111  int (*poll_frame)(AVFilterLink *link);
112 
113  /**
114  * Frame request callback. A call to this should result in at least one
115  * frame being output over the given link. This should return zero on
116  * success, and another value on error.
117  *
118  * Output pads only.
119  */
121 
122  /**
123  * Link configuration callback.
124  *
125  * For output pads, this should set the link properties such as
126  * width/height. This should NOT set the format property - that is
127  * negotiated between filters by the filter system using the
128  * query_formats() callback before this function is called.
129  *
130  * For input pads, this should check the properties of the link, and update
131  * the filter's internal state as necessary.
132  *
133  * For both input and output filters, this should return zero on success,
134  * and another value on error.
135  */
136  int (*config_props)(AVFilterLink *link);
137 
138  /**
139  * The filter expects a fifo to be inserted on its input link,
140  * typically because it has a delay.
141  *
142  * input pads only.
143  */
145 
146  /**
147  * The filter expects writable frames from its input link,
148  * duplicating data buffers if needed.
149  *
150  * input pads only.
151  */
153 };
154 #endif
155 
157  void *thread;
159 };
160 
163 };
164 
165 #if FF_API_AVFILTERBUFFER
166 /** default handler for freeing audio/video buffer when there are no references left */
167 void ff_avfilter_default_free_buffer(AVFilterBuffer *buf);
168 #endif
169 
170 /** Tell is a format is contained in the provided list terminated by -1. */
171 int ff_fmt_is_in(int fmt, const int *fmts);
172 
173 /* Functions to parse audio format arguments */
174 
175 /**
176  * Parse a pixel format.
177  *
178  * @param ret pixel format pointer to where the value should be written
179  * @param arg string to parse
180  * @param log_ctx log context
181  * @return >= 0 in case of success, a negative AVERROR code on error
182  */
183 int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx);
184 
185 /**
186  * Parse a sample rate.
187  *
188  * @param ret unsigned integer pointer to where the value should be written
189  * @param arg string to parse
190  * @param log_ctx log context
191  * @return >= 0 in case of success, a negative AVERROR code on error
192  */
193 int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx);
194 
195 /**
196  * Parse a time base.
197  *
198  * @param ret unsigned AVRational pointer to where the value should be written
199  * @param arg string to parse
200  * @param log_ctx log context
201  * @return >= 0 in case of success, a negative AVERROR code on error
202  */
203 int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx);
204 
205 /**
206  * Parse a sample format name or a corresponding integer representation.
207  *
208  * @param ret integer pointer to where the value should be written
209  * @param arg string to parse
210  * @param log_ctx log context
211  * @return >= 0 in case of success, a negative AVERROR code on error
212  */
213 int ff_parse_sample_format(int *ret, const char *arg, void *log_ctx);
214 
215 /**
216  * Parse a channel layout or a corresponding integer representation.
217  *
218  * @param ret 64bit integer pointer to where the value should be written.
219  * @param nret integer pointer to the number of channels;
220  * if not NULL, then unknown channel layouts are accepted
221  * @param arg string to parse
222  * @param log_ctx log context
223  * @return >= 0 in case of success, a negative AVERROR code on error
224  */
225 int ff_parse_channel_layout(int64_t *ret, int *nret, const char *arg,
226  void *log_ctx);
227 
228 void ff_update_link_current_pts(AVFilterLink *link, int64_t pts);
229 
231 
232 /* misc trace functions */
233 
234 /* #define FF_AVFILTER_TRACE */
235 
236 #ifdef FF_AVFILTER_TRACE
237 # define ff_tlog(pctx, ...) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__)
238 #else
239 # define ff_tlog(pctx, ...) do { if (0) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
240 #endif
241 
242 #define FF_TPRINTF_START(ctx, func) ff_tlog(NULL, "%-16s: ", #func)
243 
244 char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms);
245 
246 void ff_tlog_ref(void *ctx, AVFrame *ref, int end);
247 
248 void ff_tlog_link(void *ctx, AVFilterLink *link, int end);
249 
250 /**
251  * Insert a new pad.
252  *
253  * @param idx Insertion point. Pad is inserted at the end if this point
254  * is beyond the end of the list of pads.
255  * @param count Pointer to the number of pads in the list
256  * @param padidx_off Offset within an AVFilterLink structure to the element
257  * to increment when inserting a new pad causes link
258  * numbering to change
259  * @param pads Pointer to the pointer to the beginning of the list of pads
260  * @param links Pointer to the pointer to the beginning of the list of links
261  * @param newpad The new pad to add. A copy is made when adding.
262  * @return >= 0 in case of success, a negative AVERROR code on error
263  */
264 int ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
265  AVFilterPad **pads, AVFilterLink ***links,
266  AVFilterPad *newpad);
267 
268 /** Insert a new input pad for the filter. */
269 static inline int ff_insert_inpad(AVFilterContext *f, unsigned index,
270  AVFilterPad *p)
271 {
272  int ret = ff_insert_pad(index, &f->nb_inputs, offsetof(AVFilterLink, dstpad),
273  &f->input_pads, &f->inputs, p);
274 #if FF_API_FOO_COUNT
276  f->input_count = f->nb_inputs;
278 #endif
279  return ret;
280 }
281 
282 /** Insert a new output pad for the filter. */
283 static inline int ff_insert_outpad(AVFilterContext *f, unsigned index,
284  AVFilterPad *p)
285 {
286  int ret = ff_insert_pad(index, &f->nb_outputs, offsetof(AVFilterLink, srcpad),
287  &f->output_pads, &f->outputs, p);
288 #if FF_API_FOO_COUNT
290  f->output_count = f->nb_outputs;
292 #endif
293  return ret;
294 }
295 
296 /**
297  * Poll a frame from the filter chain.
298  *
299  * @param link the input link
300  * @return the number of immediately available frames, a negative
301  * number in case of error
302  */
303 int ff_poll_frame(AVFilterLink *link);
304 
305 /**
306  * Request an input frame from the filter at the other end of the link.
307  *
308  * @param link the input link
309  * @return zero on success
310  */
311 int ff_request_frame(AVFilterLink *link);
312 
313 #define AVFILTER_DEFINE_CLASS(fname) \
314  static const AVClass fname##_class = { \
315  .class_name = #fname, \
316  .item_name = av_default_item_name, \
317  .option = fname##_options, \
318  .version = LIBAVUTIL_VERSION_INT, \
319  .category = AV_CLASS_CATEGORY_FILTER, \
320  }
321 
322 AVFilterBufferRef *ff_copy_buffer_ref(AVFilterLink *outlink,
323  AVFilterBufferRef *ref);
324 
325 /**
326  * Find the index of a link.
327  *
328  * I.e. find i such that link == ctx->(in|out)puts[i]
329  */
330 #define FF_INLINK_IDX(link) ((int)((link)->dstpad - (link)->dst->input_pads))
331 #define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
332 
333 int ff_buffersink_read_compat(AVFilterContext *ctx, AVFilterBufferRef **buf);
334 int ff_buffersink_read_samples_compat(AVFilterContext *ctx, AVFilterBufferRef **pbuf,
335  int nb_samples);
336 /**
337  * Send a frame of data to the next filter.
338  *
339  * @param link the output link over which the data is being sent
340  * @param frame a reference to the buffer of data being sent. The
341  * receiving filter will free this reference when it no longer
342  * needs it or pass it on to the next filter.
343  *
344  * @return >= 0 on success, a negative AVERROR on error. The receiving filter
345  * is responsible for unreferencing frame in case of error.
346  */
348 
349 /**
350  * Flags for AVFilterLink.flags.
351  */
352 enum {
353 
354  /**
355  * Frame requests may need to loop in order to be fulfilled.
356  * A filter must set this flags on an output link if it may return 0 in
357  * request_frame() without filtering a frame.
358  */
360 
361 };
362 
363 /**
364  * Allocate a new filter context and return it.
365  *
366  * @param filter what filter to create an instance of
367  * @param inst_name name to give to the new filter context
368  *
369  * @return newly created filter context or NULL on failure
370  */
371 AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name);
372 
373 /**
374  * Remove a filter from a graph;
375  */
377 
378 /**
379  * Normalize the qscale factor
380  * FIXME the H264 qscale is a log based scale, mpeg1/2 is not, the code below
381  * cannot be optimal
382  */
383 static inline int ff_norm_qscale(int qscale, int type)
384 {
385  switch (type) {
386  case FF_QSCALE_TYPE_MPEG1: return qscale;
387  case FF_QSCALE_TYPE_MPEG2: return qscale >> 1;
388  case FF_QSCALE_TYPE_H264: return qscale >> 2;
389  case FF_QSCALE_TYPE_VP56: return (63 - qscale + 2) >> 2;
390  }
391  return qscale;
392 }
393 
394 #endif /* AVFILTER_INTERNAL_H */