FFmpeg 4.2.2
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
36/**
37 * Get a frame with filtered data from sink and put it in frame.
38 *
39 * @param ctx pointer to a buffersink or abuffersink filter context.
40 * @param frame pointer to an allocated frame that will be filled with data.
41 * The data must be freed using av_frame_unref() / av_frame_free()
42 * @param flags a combination of AV_BUFFERSINK_FLAG_* flags
43 *
44 * @return >= 0 in for success, a negative AVERROR code for failure.
45 */
47
48/**
49 * Tell av_buffersink_get_buffer_ref() to read video/samples buffer
50 * reference, but not remove it from the buffer. This is useful if you
51 * need only to read a video/samples buffer, without to fetch it.
52 */
53#define AV_BUFFERSINK_FLAG_PEEK 1
54
55/**
56 * Tell av_buffersink_get_buffer_ref() not to request a frame from its input.
57 * If a frame is already buffered, it is read (and removed from the buffer),
58 * but if no frame is present, return AVERROR(EAGAIN).
59 */
60#define AV_BUFFERSINK_FLAG_NO_REQUEST 2
61
62/**
63 * Struct to use for initializing a buffersink context.
64 */
65typedef struct AVBufferSinkParams {
66 const enum AVPixelFormat *pixel_fmts; ///< list of allowed pixel formats, terminated by AV_PIX_FMT_NONE
68
69/**
70 * Create an AVBufferSinkParams structure.
71 *
72 * Must be freed with av_free().
73 */
75
76/**
77 * Struct to use for initializing an abuffersink context.
78 */
79typedef struct AVABufferSinkParams {
80 const enum AVSampleFormat *sample_fmts; ///< list of allowed sample formats, terminated by AV_SAMPLE_FMT_NONE
81 const int64_t *channel_layouts; ///< list of allowed channel layouts, terminated by -1
82 const int *channel_counts; ///< list of allowed channel counts, terminated by -1
83 int all_channel_counts; ///< if not 0, accept any channel count or layout
84 int *sample_rates; ///< list of allowed sample rates, terminated by -1
86
87/**
88 * Create an AVABufferSinkParams structure.
89 *
90 * Must be freed with av_free().
91 */
93
94/**
95 * Set the frame size for an audio buffer sink.
96 *
97 * All calls to av_buffersink_get_buffer_ref will return a buffer with
98 * exactly the specified number of samples, or AVERROR(EAGAIN) if there is
99 * not enough. The last buffer at EOF will be padded with 0.
100 */
101void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size);
102
103/**
104 * @defgroup lavfi_buffersink_accessors Buffer sink accessors
105 * Get the properties of the stream
106 * @{
107 */
108
112
117
121
123
124/** @} */
125
126/**
127 * Get a frame with filtered data from sink and put it in frame.
128 *
129 * @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
130 * @param frame pointer to an allocated frame that will be filled with data.
131 * The data must be freed using av_frame_unref() / av_frame_free()
132 *
133 * @return
134 * - >= 0 if a frame was successfully returned.
135 * - AVERROR(EAGAIN) if no frames are available at this point; more
136 * input frames must be added to the filtergraph to get more output.
137 * - AVERROR_EOF if there will be no more output frames on this sink.
138 * - A different negative AVERROR code in other failure cases.
139 */
141
142/**
143 * Same as av_buffersink_get_frame(), but with the ability to specify the number
144 * of samples read. This function is less efficient than
145 * av_buffersink_get_frame(), because it copies the data around.
146 *
147 * @param ctx pointer to a context of the abuffersink AVFilter.
148 * @param frame pointer to an allocated frame that will be filled with data.
149 * The data must be freed using av_frame_unref() / av_frame_free()
150 * frame will contain exactly nb_samples audio samples, except at
151 * the end of stream, when it can contain less than nb_samples.
152 *
153 * @return The return codes have the same meaning as for
154 * av_buffersink_get_frame().
155 *
156 * @warning do not mix this function with av_buffersink_get_frame(). Use only one or
157 * the other with a single sink, not both.
158 */
160
161/**
162 * @}
163 */
164
165#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)
uint64_t av_buffersink_get_channel_layout(const AVFilterContext *ctx)
int av_buffersink_get_h(const AVFilterContext *ctx)
AVRational av_buffersink_get_sample_aspect_ratio(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.
AVABufferSinkParams * av_abuffersink_params_alloc(void)
Create an AVABufferSinkParams structure.
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.
AVBufferSinkParams * av_buffersink_params_alloc(void)
Create an AVBufferSinkParams structure.
AVMediaType
Definition: avutil.h:199
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
Struct to use for initializing an abuffersink context.
Definition: buffersink.h:79
const int64_t * channel_layouts
list of allowed channel layouts, terminated by -1
Definition: buffersink.h:81
int all_channel_counts
if not 0, accept any channel count or layout
Definition: buffersink.h:83
int * sample_rates
list of allowed sample rates, terminated by -1
Definition: buffersink.h:84
const int * channel_counts
list of allowed channel counts, terminated by -1
Definition: buffersink.h:82
enum AVSampleFormat * sample_fmts
list of allowed sample formats, terminated by AV_SAMPLE_FMT_NONE
Definition: buffersink.h:80
A reference to a data buffer.
Definition: buffer.h:81
Struct to use for initializing a buffersink context.
Definition: buffersink.h:65
enum AVPixelFormat * pixel_fmts
list of allowed pixel formats, terminated by AV_PIX_FMT_NONE
Definition: buffersink.h:66
An instance of a filter.
Definition: avfilter.h:338
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
Rational number (pair of numerator and denominator).
Definition: rational.h:58