FFmpeg 7.1.1
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buffersink.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_BUFFERSINK_H
20#define AVFILTER_BUFFERSINK_H
21
22/**
23 * @file
24 * @ingroup lavfi_buffersink
25 * memory buffer sink API for audio and video
26 */
27
28#include "avfilter.h"
29
30/**
31 * @defgroup lavfi_buffersink Buffer sink API
32 * @ingroup lavfi
33 * @{
34 *
35 * The buffersink and abuffersink filters are there to connect filter graphs
36 * to applications. They have a single input, connected to the graph, and no
37 * output. Frames must be extracted using av_buffersink_get_frame() or
38 * av_buffersink_get_samples().
39 *
40 * The format negotiated by the graph during configuration can be obtained
41 * using the accessor functions:
42 * - av_buffersink_get_time_base(),
43 * - av_buffersink_get_format(),
44 * - av_buffersink_get_frame_rate(),
45 * - av_buffersink_get_w(),
46 * - av_buffersink_get_h(),
47 * - av_buffersink_get_sample_aspect_ratio(),
48 * - av_buffersink_get_channels(),
49 * - av_buffersink_get_ch_layout(),
50 * - av_buffersink_get_sample_rate().
51 *
52 * The layout returned by av_buffersink_get_ch_layout() must de uninitialized
53 * by the caller.
54 *
55 * The format can be constrained by setting options, using av_opt_set() and
56 * related functions with the AV_OPT_SEARCH_CHILDREN flag.
57 * - pix_fmts (int list),
58 * - color_spaces (int list),
59 * - color_ranges (int list),
60 * - sample_fmts (int list),
61 * - sample_rates (int list),
62 * - ch_layouts (string),
63 * - channel_counts (int list),
64 * - all_channel_counts (bool).
65 * Most of these options are of type binary, and should be set using
66 * av_opt_set_int_list() or av_opt_set_bin(). If they are not set, all
67 * corresponding formats are accepted.
68 *
69 * As a special case, if ch_layouts is not set, all valid channel layouts are
70 * accepted except for UNSPEC layouts, unless all_channel_counts is set.
71 */
72
73/**
74 * Get a frame with filtered data from sink and put it in frame.
75 *
76 * @param ctx pointer to a buffersink or abuffersink filter context.
77 * @param frame pointer to an allocated frame that will be filled with data.
78 * The data must be freed using av_frame_unref() / av_frame_free()
79 * @param flags a combination of AV_BUFFERSINK_FLAG_* flags
80 *
81 * @return >= 0 in for success, a negative AVERROR code for failure.
82 */
84
85/**
86 * Tell av_buffersink_get_buffer_ref() to read video/samples buffer
87 * reference, but not remove it from the buffer. This is useful if you
88 * need only to read a video/samples buffer, without to fetch it.
89 */
90#define AV_BUFFERSINK_FLAG_PEEK 1
91
92/**
93 * Tell av_buffersink_get_buffer_ref() not to request a frame from its input.
94 * If a frame is already buffered, it is read (and removed from the buffer),
95 * but if no frame is present, return AVERROR(EAGAIN).
96 */
97#define AV_BUFFERSINK_FLAG_NO_REQUEST 2
98
99/**
100 * Set the frame size for an audio buffer sink.
101 *
102 * All calls to av_buffersink_get_buffer_ref will return a buffer with
103 * exactly the specified number of samples, or AVERROR(EAGAIN) if there is
104 * not enough. The last buffer at EOF will be padded with 0.
105 */
106void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size);
107
108/**
109 * @defgroup lavfi_buffersink_accessors Buffer sink accessors
110 * Get the properties of the stream
111 * @{
112 */
113
117
124
127 AVChannelLayout *ch_layout);
129
131
132/** @} */
133
134/**
135 * Get a frame with filtered data from sink and put it in frame.
136 *
137 * @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
138 * @param frame pointer to an allocated frame that will be filled with data.
139 * The data must be freed using av_frame_unref() / av_frame_free()
140 *
141 * @return
142 * - >= 0 if a frame was successfully returned.
143 * - AVERROR(EAGAIN) if no frames are available at this point; more
144 * input frames must be added to the filtergraph to get more output.
145 * - AVERROR_EOF if there will be no more output frames on this sink.
146 * - A different negative AVERROR code in other failure cases.
147 */
149
150/**
151 * Same as av_buffersink_get_frame(), but with the ability to specify the number
152 * of samples read. This function is less efficient than
153 * av_buffersink_get_frame(), because it copies the data around.
154 *
155 * @param ctx pointer to a context of the abuffersink AVFilter.
156 * @param frame pointer to an allocated frame that will be filled with data.
157 * The data must be freed using av_frame_unref() / av_frame_free()
158 * frame will contain exactly nb_samples audio samples, except at
159 * the end of stream, when it can contain less than nb_samples.
160 *
161 * @return The return codes have the same meaning as for
162 * av_buffersink_get_frame().
163 *
164 * @warning do not mix this function with av_buffersink_get_frame(). Use only one or
165 * the other with a single sink, not both.
166 */
168
169/**
170 * @}
171 */
172
173#endif /* AVFILTER_BUFFERSINK_H */
Main libavfilter public API header.
static AVFrame * frame
AVBufferRef * av_buffersink_get_hw_frames_ctx(const AVFilterContext *ctx)
enum AVMediaType av_buffersink_get_type(const AVFilterContext *ctx)
int av_buffersink_get_sample_rate(const AVFilterContext *ctx)
int av_buffersink_get_format(const AVFilterContext *ctx)
AVRational av_buffersink_get_frame_rate(const AVFilterContext *ctx)
int av_buffersink_get_h(const AVFilterContext *ctx)
AVRational av_buffersink_get_sample_aspect_ratio(const AVFilterContext *ctx)
enum AVColorSpace av_buffersink_get_colorspace(const AVFilterContext *ctx)
int av_buffersink_get_ch_layout(const AVFilterContext *ctx, AVChannelLayout *ch_layout)
enum AVColorRange av_buffersink_get_color_range(const AVFilterContext *ctx)
AVRational av_buffersink_get_time_base(const AVFilterContext *ctx)
int av_buffersink_get_w(const AVFilterContext *ctx)
int av_buffersink_get_channels(const AVFilterContext *ctx)
void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size)
Set the frame size for an audio buffer sink.
int av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame)
Get a frame with filtered data from sink and put it in frame.
int av_buffersink_get_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags)
Get a frame with filtered data from sink and put it in frame.
int av_buffersink_get_samples(AVFilterContext *ctx, AVFrame *frame, int nb_samples)
Same as av_buffersink_get_frame(), but with the ability to specify the number of samples read.
AVMediaType
Definition avutil.h:199
AVColorRange
Visual content value range.
Definition pixfmt.h:651
AVColorSpace
YUV colorspace type.
Definition pixfmt.h:609
A reference to a data buffer.
Definition buffer.h:82
An AVChannelLayout holds information about the channel layout of audio data.
An instance of a filter.
Definition avfilter.h:457
This structure describes decoded (raw) audio or video data.
Definition frame.h:389
Rational number (pair of numerator and denominator).
Definition rational.h:58