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
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  */
107 
108 /**
109  * @defgroup lavfi_buffersink_accessors Buffer sink accessors
110  * Get the properties of the stream
111  * @{
112  */
113 
117 
124 
126 #if FF_API_OLD_CHANNEL_LAYOUT
128 uint64_t av_buffersink_get_channel_layout (const AVFilterContext *ctx);
129 #endif
131  AVChannelLayout *ch_layout);
133 
135 
136 /** @} */
137 
138 /**
139  * Get a frame with filtered data from sink and put it in frame.
140  *
141  * @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
142  * @param frame pointer to an allocated frame that will be filled with data.
143  * The data must be freed using av_frame_unref() / av_frame_free()
144  *
145  * @return
146  * - >= 0 if a frame was successfully returned.
147  * - AVERROR(EAGAIN) if no frames are available at this point; more
148  * input frames must be added to the filtergraph to get more output.
149  * - AVERROR_EOF if there will be no more output frames on this sink.
150  * - A different negative AVERROR code in other failure cases.
151  */
153 
154 /**
155  * Same as av_buffersink_get_frame(), but with the ability to specify the number
156  * of samples read. This function is less efficient than
157  * av_buffersink_get_frame(), because it copies the data around.
158  *
159  * @param ctx pointer to a context of the abuffersink AVFilter.
160  * @param frame pointer to an allocated frame that will be filled with data.
161  * The data must be freed using av_frame_unref() / av_frame_free()
162  * frame will contain exactly nb_samples audio samples, except at
163  * the end of stream, when it can contain less than nb_samples.
164  *
165  * @return The return codes have the same meaning as for
166  * av_buffersink_get_frame().
167  *
168  * @warning do not mix this function with av_buffersink_get_frame(). Use only one or
169  * the other with a single sink, not both.
170  */
172 
173 /**
174  * @}
175  */
176 
177 #endif /* AVFILTER_BUFFERSINK_H */
av_buffersink_get_ch_layout
int av_buffersink_get_ch_layout(const AVFilterContext *ctx, AVChannelLayout *ch_layout)
Definition: buffersink.c:234
av_buffersink_get_samples
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:156
av_buffersink_get_sample_aspect_ratio
AVRational av_buffersink_get_sample_aspect_ratio(const AVFilterContext *ctx)
av_buffersink_get_frame_flags
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:151
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
av_buffersink_get_hw_frames_ctx
AVBufferRef * av_buffersink_get_hw_frames_ctx(const AVFilterContext *ctx)
av_buffersink_set_frame_size
void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size)
Set the frame size for an audio buffer sink.
Definition: buffersink.c:195
av_buffersink_get_frame_rate
AVRational av_buffersink_get_frame_rate(const AVFilterContext *ctx)
frame_size
int frame_size
Definition: mxfenc.c:2422
av_buffersink_get_frame
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:99
av_buffersink_get_format
int av_buffersink_get_format(const AVFilterContext *ctx)
av_buffersink_get_time_base
AVRational av_buffersink_get_time_base(const AVFilterContext *ctx)
ctx
AVFormatContext * ctx
Definition: movenc.c:48
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVMediaType
AVMediaType
Definition: avutil.h:199
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:313
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
av_buffersink_get_type
enum AVMediaType av_buffersink_get_type(const AVFilterContext *ctx)
av_buffersink_get_w
int av_buffersink_get_w(const AVFilterContext *ctx)
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:613
av_buffersink_get_h
int av_buffersink_get_h(const AVFilterContext *ctx)
av_buffersink_get_sample_rate
int av_buffersink_get_sample_rate(const AVFilterContext *ctx)
avfilter.h
av_buffersink_get_channels
int av_buffersink_get_channels(const AVFilterContext *ctx)
Definition: buffersink.c:228
AVFilterContext
An instance of a filter.
Definition: avfilter.h:409
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
av_buffersink_get_colorspace
enum AVColorSpace av_buffersink_get_colorspace(const AVFilterContext *ctx)
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:652
av_buffersink_get_color_range
enum AVColorRange av_buffersink_get_color_range(const AVFilterContext *ctx)