2 * This file is part of Libav.
4 * Libav 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.
9 * Libav 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.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with Libav; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef AVFILTER_INTERNAL_H
20 #define AVFILTER_INTERNAL_H
24 * internal API functions
29 #if !FF_API_AVFILTERPAD_PUBLIC
31 * A filter pad used for either input or output.
35 * Pad name. The name is unique among inputs and among outputs, but an
36 * input may have the same name as an output. This may be NULL if this
37 * pad has no need to ever be referenced by name.
44 enum AVMediaType type;
47 * Minimum required permissions on incoming buffers. Any buffer with
48 * insufficient permissions will be automatically copied by the filter
49 * system to a new buffer which provides the needed access permissions.
56 * Permissions which are not accepted on incoming buffers. Any buffer
57 * which has any of these permissions set will be automatically copied
58 * by the filter system to a new buffer which does not have those
59 * permissions. This can be used to easily disallow buffers with
67 * Callback called before passing the first slice of a new frame. If
68 * NULL, the filter layer will default to storing a reference to the
69 * picture inside the link structure.
71 * Input video pads only.
73 * @return >= 0 on success, a negative AVERROR on error. picref will be
74 * unreferenced by the caller in case of error.
76 void (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref);
79 * Callback function to get a video buffer. If NULL, the filter system will
80 * use avfilter_default_get_video_buffer().
82 * Input video pads only.
84 AVFilterBufferRef *(*get_video_buffer)(AVFilterLink *link, int perms, int w, int h);
87 * Callback function to get an audio buffer. If NULL, the filter system will
88 * use avfilter_default_get_audio_buffer().
90 * Input audio pads only.
92 AVFilterBufferRef *(*get_audio_buffer)(AVFilterLink *link, int perms,
96 * Callback called after the slices of a frame are completely sent. If
97 * NULL, the filter layer will default to releasing the reference stored
98 * in the link structure during start_frame().
100 * Input video pads only.
102 void (*end_frame)(AVFilterLink *link);
105 * Slice drawing callback. This is where a filter receives video data
106 * and should do its processing.
108 * Input video pads only.
110 * @return >= 0 on success, a negative AVERROR on error.
112 int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir);
115 * Samples filtering callback. This is where a filter receives audio data
116 * and should do its processing.
118 * Input audio pads only.
120 * @return >= 0 on success, a negative AVERROR on error. This function
121 * must ensure that samplesref is properly unreferenced on error if it
122 * hasn't been passed on to another filter.
124 int (*filter_samples)(AVFilterLink *link, AVFilterBufferRef *samplesref);
127 * Frame poll callback. This returns the number of immediately available
128 * samples. It should return a positive value if the next request_frame()
129 * is guaranteed to return one frame (with no delay).
131 * Defaults to just calling the source poll_frame() method.
135 int (*poll_frame)(AVFilterLink *link);
138 * Frame request callback. A call to this should result in at least one
139 * frame being output over the given link. This should return zero on
140 * success, and another value on error.
144 int (*request_frame)(AVFilterLink *link);
147 * Link configuration callback.
149 * For output pads, this should set the link properties such as
150 * width/height. This should NOT set the format property - that is
151 * negotiated between filters by the filter system using the
152 * query_formats() callback before this function is called.
154 * For input pads, this should check the properties of the link, and update
155 * the filter's internal state as necessary.
157 * For both input and output filters, this should return zero on success,
158 * and another value on error.
160 int (*config_props)(AVFilterLink *link);
163 * The filter expects a fifo to be inserted on its input link,
164 * typically because it has a delay.
172 /** default handler for freeing audio/video buffer when there are no references left */
173 void ff_avfilter_default_free_buffer(AVFilterBuffer *buf);
175 /** Tell is a format is contained in the provided list terminated by -1. */
176 int ff_fmt_is_in(int fmt, const int *fmts);
178 #define FF_DPRINTF_START(ctx, func) av_dlog(NULL, "%-16s: ", #func)
180 void ff_dlog_link(void *ctx, AVFilterLink *link, int end);
185 * @param idx Insertion point. Pad is inserted at the end if this point
186 * is beyond the end of the list of pads.
187 * @param count Pointer to the number of pads in the list
188 * @param padidx_off Offset within an AVFilterLink structure to the element
189 * to increment when inserting a new pad causes link
190 * numbering to change
191 * @param pads Pointer to the pointer to the beginning of the list of pads
192 * @param links Pointer to the pointer to the beginning of the list of links
193 * @param newpad The new pad to add. A copy is made when adding.
195 void ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
196 AVFilterPad **pads, AVFilterLink ***links,
197 AVFilterPad *newpad);
199 /** Insert a new input pad for the filter. */
200 static inline void ff_insert_inpad(AVFilterContext *f, unsigned index,
203 ff_insert_pad(index, &f->nb_inputs, offsetof(AVFilterLink, dstpad),
204 &f->input_pads, &f->inputs, p);
206 f->input_count = f->nb_inputs;
210 /** Insert a new output pad for the filter. */
211 static inline void ff_insert_outpad(AVFilterContext *f, unsigned index,
214 ff_insert_pad(index, &f->nb_outputs, offsetof(AVFilterLink, srcpad),
215 &f->output_pads, &f->outputs, p);
217 f->output_count = f->nb_outputs;
222 * Poll a frame from the filter chain.
224 * @param link the input link
225 * @return the number of immediately available frames, a negative
226 * number in case of error
228 int ff_poll_frame(AVFilterLink *link);
231 * Request an input frame from the filter at the other end of the link.
233 * @param link the input link
234 * @return zero on success
236 int ff_request_frame(AVFilterLink *link);
238 #endif /* AVFILTER_INTERNAL_H */