FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/filters.h
Date: 2022-12-05 20:26:17
Exec Total Coverage
Lines: 5 5 100.0%
Functions: 2 2 100.0%
Branches: 0 0 -%

Line Branch Exec Source
1 /*
2 * Filters implementation helper functions
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public License
8 * as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public License
17 * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef AVFILTER_FILTERS_H
22 #define AVFILTER_FILTERS_H
23
24 /**
25 * Filters implementation helper functions
26 */
27
28 #include "avfilter.h"
29 #include "internal.h"
30
31 /**
32 * Special return code when activate() did not do anything.
33 */
34 #define FFERROR_NOT_READY FFERRTAG('N','R','D','Y')
35
36 /**
37 * Mark a filter ready and schedule it for activation.
38 *
39 * This is automatically done when something happens to the filter (queued
40 * frame, status change, request on output).
41 * Filters implementing the activate callback can call it directly to
42 * perform one more round of processing later.
43 * It is also useful for filters reacting to external or asynchronous
44 * events.
45 */
46 void ff_filter_set_ready(AVFilterContext *filter, unsigned priority);
47
48 /**
49 * Process the commands queued in the link up to the time of the frame.
50 * Commands will trigger the process_command() callback.
51 * @return >= 0 or AVERROR code.
52 */
53 int ff_inlink_process_commands(AVFilterLink *link, const AVFrame *frame);
54
55 /**
56 * Evaluate the timeline expression of the link for the time and properties
57 * of the frame.
58 * @return >0 if enabled, 0 if disabled
59 * @note It does not update link->dst->is_disabled.
60 */
61 int ff_inlink_evaluate_timeline_at_frame(AVFilterLink *link, const AVFrame *frame);
62
63 /**
64 * Get the number of frames available on the link.
65 * @return the number of frames available in the link fifo.
66 */
67 size_t ff_inlink_queued_frames(AVFilterLink *link);
68
69 /**
70 * Test if a frame is available on the link.
71 * @return >0 if a frame is available
72 */
73 int ff_inlink_check_available_frame(AVFilterLink *link);
74
75
76 /***
77 * Get the number of samples available on the link.
78 * @return the numer of samples available on the link.
79 */
80 int ff_inlink_queued_samples(AVFilterLink *link);
81
82 /**
83 * Test if enough samples are available on the link.
84 * @return >0 if enough samples are available
85 * @note on EOF and error, min becomes 1
86 */
87 int ff_inlink_check_available_samples(AVFilterLink *link, unsigned min);
88
89 /**
90 * Take a frame from the link's FIFO and update the link's stats.
91 *
92 * If ff_inlink_check_available_frame() was previously called, the
93 * preferred way of expressing it is "av_assert1(ret);" immediately after
94 * ff_inlink_consume_frame(). Negative error codes must still be checked.
95 *
96 * @note May trigger process_command() and/or update is_disabled.
97 * @return >0 if a frame is available,
98 * 0 and set rframe to NULL if no frame available,
99 * or AVERROR code
100 */
101 int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe);
102
103 /**
104 * Take samples from the link's FIFO and update the link's stats.
105 *
106 * If ff_inlink_check_available_samples() was previously called, the
107 * preferred way of expressing it is "av_assert1(ret);" immediately after
108 * ff_inlink_consume_samples(). Negative error codes must still be checked.
109 *
110 * @note May trigger process_command() and/or update is_disabled.
111 * @return >0 if a frame is available,
112 * 0 and set rframe to NULL if no frame available,
113 * or AVERROR code
114 */
115 int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max,
116 AVFrame **rframe);
117
118 /**
119 * Access a frame in the link fifo without consuming it.
120 * The first frame is numbered 0; the designated frame must exist.
121 * @return the frame at idx position in the link fifo.
122 */
123 AVFrame *ff_inlink_peek_frame(AVFilterLink *link, size_t idx);
124
125 /**
126 * Make sure a frame is writable.
127 * This is similar to av_frame_make_writable() except it uses the link's
128 * buffer allocation callback, and therefore allows direct rendering.
129 */
130 int ff_inlink_make_frame_writable(AVFilterLink *link, AVFrame **rframe);
131
132 /**
133 * Test and acknowledge the change of status on the link.
134 *
135 * Status means EOF or an error condition; a change from the normal (0)
136 * status to a non-zero status can be queued in a filter's input link, it
137 * becomes relevant after the frames queued in the link's FIFO are
138 * processed. This function tests if frames are still queued and if a queued
139 * status change has not yet been processed. In that case it performs basic
140 * treatment (updating the link's timestamp) and returns a positive value to
141 * let the filter do its own treatments (flushing...).
142 *
143 * Filters implementing the activate callback should call this function when
144 * they think it might succeed (usually after checking unsuccessfully for a
145 * queued frame).
146 * Filters implementing the filter_frame and request_frame callbacks do not
147 * need to call that since the same treatment happens in ff_filter_frame().
148 *
149 * @param[out] rstatus new or current status
150 * @param[out] rpts current timestamp of the link in link time base
151 * @return >0 if status changed, <0 if status already acked, 0 otherwise
152 */
153 int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts);
154
155 /**
156 * Mark that a frame is wanted on the link.
157 * Unlike ff_filter_frame(), it must not be called when the link has a
158 * non-zero status, and thus does not acknowledge it.
159 * Also it cannot fail.
160 */
161 void ff_inlink_request_frame(AVFilterLink *link);
162
163 /**
164 * Set the status on an input link.
165 * Also discard all frames in the link's FIFO.
166 */
167 void ff_inlink_set_status(AVFilterLink *link, int status);
168
169 /**
170 * Test if a frame is wanted on an output link.
171 */
172 29128 static inline int ff_outlink_frame_wanted(AVFilterLink *link)
173 {
174 29128 return link->frame_wanted_out;
175 }
176
177 /**
178 * Get the status on an output link.
179 */
180 int ff_outlink_get_status(AVFilterLink *link);
181
182 /**
183 * Set the status field of a link from the source filter.
184 * The pts should reflect the timestamp of the status change,
185 * in link time base and relative to the frames timeline.
186 * In particular, for AVERROR_EOF, it should reflect the
187 * end time of the last frame.
188 */
189 288 static inline void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
190 {
191 288 ff_avfilter_link_set_in_status(link, status, pts);
192 288 }
193
194 /**
195 * Forward the status on an output link to an input link.
196 * If the status is set, it will discard all queued frames and this macro
197 * will return immediately.
198 */
199 #define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink) do { \
200 int ret = ff_outlink_get_status(outlink); \
201 if (ret) { \
202 ff_inlink_set_status(inlink, ret); \
203 return 0; \
204 } \
205 } while (0)
206
207 /**
208 * Forward the status on an output link to all input links.
209 * If the status is set, it will discard all queued frames and this macro
210 * will return immediately.
211 */
212 #define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter) do { \
213 int ret = ff_outlink_get_status(outlink); \
214 if (ret) { \
215 unsigned i; \
216 for (i = 0; i < filter->nb_inputs; i++) \
217 ff_inlink_set_status(filter->inputs[i], ret); \
218 return 0; \
219 } \
220 } while (0)
221
222 /**
223 * Acknowledge the status on an input link and forward it to an output link.
224 * If the status is set, this macro will return immediately.
225 */
226 #define FF_FILTER_FORWARD_STATUS(inlink, outlink) do { \
227 int status; \
228 int64_t pts; \
229 if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
230 ff_outlink_set_status(outlink, status, pts); \
231 return 0; \
232 } \
233 } while (0)
234
235 /**
236 * Acknowledge the status on an input link and forward it to an output link.
237 * If the status is set, this macro will return immediately.
238 */
239 #define FF_FILTER_FORWARD_STATUS_ALL(inlink, filter) do { \
240 int status; \
241 int64_t pts; \
242 if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
243 unsigned i; \
244 for (i = 0; i < filter->nb_outputs; i++) \
245 ff_outlink_set_status(filter->outputs[i], status, pts); \
246 return 0; \
247 } \
248 } while (0)
249
250 /**
251 * Forward the frame_wanted_out flag from an output link to an input link.
252 * If the flag is set, this macro will return immediately.
253 */
254 #define FF_FILTER_FORWARD_WANTED(outlink, inlink) do { \
255 if (ff_outlink_frame_wanted(outlink)) { \
256 ff_inlink_request_frame(inlink); \
257 return 0; \
258 } \
259 } while (0)
260
261 /**
262 * Check for flow control between input and output.
263 * This is necessary for filters that may produce several output frames for
264 * a single input event, otherwise they may produce them all at once,
265 * causing excessive memory consumption.
266 */
267 int ff_inoutlink_check_flow(AVFilterLink *inlink, AVFilterLink *outlink);
268
269 #endif /* AVFILTER_FILTERS_H */
270