FFmpeg  4.3.1
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  *
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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 #if FF_API_NEXT
63 /**
64  * Struct to use for initializing a buffersink context.
65  */
66 typedef struct AVBufferSinkParams {
67  const enum AVPixelFormat *pixel_fmts; ///< list of allowed pixel formats, terminated by AV_PIX_FMT_NONE
68 } AVBufferSinkParams;
69 
70 /**
71  * Create an AVBufferSinkParams structure.
72  *
73  * Must be freed with av_free().
74  */
76 AVBufferSinkParams *av_buffersink_params_alloc(void);
77 
78 /**
79  * Struct to use for initializing an abuffersink context.
80  */
81 typedef struct AVABufferSinkParams {
82  const enum AVSampleFormat *sample_fmts; ///< list of allowed sample formats, terminated by AV_SAMPLE_FMT_NONE
83  const int64_t *channel_layouts; ///< list of allowed channel layouts, terminated by -1
84  const int *channel_counts; ///< list of allowed channel counts, terminated by -1
85  int all_channel_counts; ///< if not 0, accept any channel count or layout
86  int *sample_rates; ///< list of allowed sample rates, terminated by -1
87 } AVABufferSinkParams;
88 
89 /**
90  * Create an AVABufferSinkParams structure.
91  *
92  * Must be freed with av_free().
93  */
95 AVABufferSinkParams *av_abuffersink_params_alloc(void);
96 #endif
97 
98 /**
99  * Set the frame size for an audio buffer sink.
100  *
101  * All calls to av_buffersink_get_buffer_ref will return a buffer with
102  * exactly the specified number of samples, or AVERROR(EAGAIN) if there is
103  * not enough. The last buffer at EOF will be padded with 0.
104  */
105 void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size);
106 
107 /**
108  * @defgroup lavfi_buffersink_accessors Buffer sink accessors
109  * Get the properties of the stream
110  * @{
111  */
112 
116 
121 
125 
127 
128 /** @} */
129 
130 /**
131  * Get a frame with filtered data from sink and put it in frame.
132  *
133  * @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
134  * @param frame pointer to an allocated frame that will be filled with data.
135  * The data must be freed using av_frame_unref() / av_frame_free()
136  *
137  * @return
138  * - >= 0 if a frame was successfully returned.
139  * - AVERROR(EAGAIN) if no frames are available at this point; more
140  * input frames must be added to the filtergraph to get more output.
141  * - AVERROR_EOF if there will be no more output frames on this sink.
142  * - A different negative AVERROR code in other failure cases.
143  */
145 
146 /**
147  * Same as av_buffersink_get_frame(), but with the ability to specify the number
148  * of samples read. This function is less efficient than
149  * av_buffersink_get_frame(), because it copies the data around.
150  *
151  * @param ctx pointer to a context of the abuffersink AVFilter.
152  * @param frame pointer to an allocated frame that will be filled with data.
153  * The data must be freed using av_frame_unref() / av_frame_free()
154  * frame will contain exactly nb_samples audio samples, except at
155  * the end of stream, when it can contain less than nb_samples.
156  *
157  * @return The return codes have the same meaning as for
158  * av_buffersink_get_frame().
159  *
160  * @warning do not mix this function with av_buffersink_get_frame(). Use only one or
161  * the other with a single sink, not both.
162  */
164 
165 /**
166  * @}
167  */
168 
169 #endif /* AVFILTER_BUFFERSINK_H */
#define attribute_deprecated
Definition: attributes.h:100
Main libavfilter public API header.
static AVFrame * frame
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)
AVBufferRef * av_buffersink_get_hw_frames_ctx(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.
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
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
A reference to a data buffer.
Definition: buffer.h:81
An instance of a filter.
Definition: avfilter.h:338
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
Rational number (pair of numerator and denominator).
Definition: rational.h:58