FFmpeg
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
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8  *
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12  * Lesser General Public License for more details.
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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  */
65 typedef 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  */
79 typedef 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  */
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 */
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVBufferSinkParams * av_buffersink_params_alloc(void)
Create an AVBufferSinkParams structure.
Definition: buffersink.c:130
Main libavfilter public API header.
const int * channel_counts
list of allowed channel counts, terminated by -1
Definition: buffersink.h:82
AVABufferSinkParams * av_abuffersink_params_alloc(void)
Create an AVABufferSinkParams structure.
Definition: buffersink.c:141
enum AVSampleFormat * sample_fmts
list of allowed sample formats, terminated by AV_SAMPLE_FMT_NONE
Definition: buffersink.h:80
int av_buffersink_get_sample_rate(const AVFilterContext *ctx)
AVRational av_buffersink_get_frame_rate(const AVFilterContext *ctx)
AVBufferRef * av_buffersink_get_hw_frames_ctx(const AVFilterContext *ctx)
int av_buffersink_get_h(const AVFilterContext *ctx)
int av_buffersink_get_format(const AVFilterContext *ctx)
int * sample_rates
list of allowed sample rates, terminated by -1
Definition: buffersink.h:84
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.
Definition: buffersink.c:119
Struct to use for initializing an abuffersink context.
Definition: buffersink.h:79
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...
Definition: buffersink.c:124
AVFormatContext * ctx
Definition: movenc.c:48
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Struct to use for initializing a buffersink context.
Definition: buffersink.h:65
AVRational av_buffersink_get_sample_aspect_ratio(const AVFilterContext *ctx)
int frame_size
Definition: mxfenc.c:2216
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
uint64_t av_buffersink_get_channel_layout(const AVFilterContext *ctx)
int all_channel_counts
if not 0, accept any channel count or layout
Definition: buffersink.h:83
enum AVMediaType av_buffersink_get_type(const AVFilterContext *ctx)
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVMediaType
Definition: avutil.h:199
int av_buffersink_get_w(const AVFilterContext *ctx)
#define flags(name, subs,...)
Definition: cbs_av1.c:561
A reference to a data buffer.
Definition: buffer.h:81
enum AVPixelFormat * pixel_fmts
list of allowed pixel formats, terminated by AV_PIX_FMT_NONE
Definition: buffersink.h:66
void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size)
Set the frame size for an audio buffer sink.
Definition: buffersink.c:175
int av_buffersink_get_channels(const AVFilterContext *ctx)
An instance of a filter.
Definition: avfilter.h:338
int av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame)
Get a frame with filtered data from sink and put it in frame.
Definition: buffersink.c:67
const int64_t * channel_layouts
list of allowed channel layouts, terminated by -1
Definition: buffersink.h:81
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVRational av_buffersink_get_time_base(const AVFilterContext *ctx)