1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVFILTER_BUFFERSINK_H
#define AVFILTER_BUFFERSINK_H
/**
* @file
* @ingroup lavfi_buffersink
* memory buffer sink API for audio and video
*/
#include "avfilter.h"
/**
* @defgroup lavfi_buffersink Buffer sink API
* @ingroup lavfi
* @{
*
* The buffersink and abuffersink filters are there to connect filter graphs
* to applications. They have a single input, connected to the graph, and no
* output. Frames must be extracted using av_buffersink_get_frame() or
* av_buffersink_get_samples().
*
* The format negotiated by the graph during configuration can be obtained
* using the accessor functions:
* - av_buffersink_get_time_base(),
* - av_buffersink_get_format(),
* - av_buffersink_get_frame_rate(),
* - av_buffersink_get_w(),
* - av_buffersink_get_h(),
* - av_buffersink_get_sample_aspect_ratio(),
* - av_buffersink_get_channels(),
* - av_buffersink_get_ch_layout(),
* - av_buffersink_get_sample_rate().
*
* The layout returned by av_buffersink_get_ch_layout() must de uninitialized
* by the caller.
*
* The format can be constrained by setting options, using av_opt_set() and
* related functions with the AV_OPT_SEARCH_CHILDREN flag.
* - pix_fmts (int list),
* - sample_fmts (int list),
* - sample_rates (int list),
* - ch_layouts (string),
* - channel_counts (int list),
* - all_channel_counts (bool).
* Most of these options are of type binary, and should be set using
* av_opt_set_int_list() or av_opt_set_bin(). If they are not set, all
* corresponding formats are accepted.
*
* As a special case, if ch_layouts is not set, all valid channel layouts are
* accepted except for UNSPEC layouts, unless all_channel_counts is set.
*/
/**
* Get a frame with filtered data from sink and put it in frame.
*
* @param ctx pointer to a buffersink or abuffersink filter context.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
* @param flags a combination of AV_BUFFERSINK_FLAG_* flags
*
* @return >= 0 in for success, a negative AVERROR code for failure.
*/
int av_buffersink_get_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags);
/**
* Tell av_buffersink_get_buffer_ref() to read video/samples buffer
* reference, but not remove it from the buffer. This is useful if you
* need only to read a video/samples buffer, without to fetch it.
*/
#define AV_BUFFERSINK_FLAG_PEEK 1
/**
* Tell av_buffersink_get_buffer_ref() not to request a frame from its input.
* If a frame is already buffered, it is read (and removed from the buffer),
* but if no frame is present, return AVERROR(EAGAIN).
*/
#define AV_BUFFERSINK_FLAG_NO_REQUEST 2
/**
* Set the frame size for an audio buffer sink.
*
* All calls to av_buffersink_get_buffer_ref will return a buffer with
* exactly the specified number of samples, or AVERROR(EAGAIN) if there is
* not enough. The last buffer at EOF will be padded with 0.
*/
void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size);
/**
* @defgroup lavfi_buffersink_accessors Buffer sink accessors
* Get the properties of the stream
* @{
*/
enum AVMediaType av_buffersink_get_type (const AVFilterContext *ctx);
AVRational av_buffersink_get_time_base (const AVFilterContext *ctx);
int av_buffersink_get_format (const AVFilterContext *ctx);
AVRational av_buffersink_get_frame_rate (const AVFilterContext *ctx);
int av_buffersink_get_w (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);
enum AVColorRange av_buffersink_get_color_range (const AVFilterContext *ctx);
int av_buffersink_get_channels (const AVFilterContext *ctx);
#if FF_API_OLD_CHANNEL_LAYOUT
attribute_deprecated
uint64_t av_buffersink_get_channel_layout (const AVFilterContext *ctx);
#endif
int av_buffersink_get_ch_layout (const AVFilterContext *ctx,
AVChannelLayout *ch_layout);
int av_buffersink_get_sample_rate (const AVFilterContext *ctx);
AVBufferRef * av_buffersink_get_hw_frames_ctx (const AVFilterContext *ctx);
/** @} */
/**
* Get a frame with filtered data from sink and put it in frame.
*
* @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
*
* @return
* - >= 0 if a frame was successfully returned.
* - AVERROR(EAGAIN) if no frames are available at this point; more
* input frames must be added to the filtergraph to get more output.
* - AVERROR_EOF if there will be no more output frames on this sink.
* - A different negative AVERROR code in other failure cases.
*/
int av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame);
/**
* Same as av_buffersink_get_frame(), but with the ability to specify the number
* of samples read. This function is less efficient than
* av_buffersink_get_frame(), because it copies the data around.
*
* @param ctx pointer to a context of the abuffersink AVFilter.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
* frame will contain exactly nb_samples audio samples, except at
* the end of stream, when it can contain less than nb_samples.
*
* @return The return codes have the same meaning as for
* av_buffersink_get_frame().
*
* @warning do not mix this function with av_buffersink_get_frame(). Use only one or
* the other with a single sink, not both.
*/
int av_buffersink_get_samples(AVFilterContext *ctx, AVFrame *frame, int nb_samples);
/**
* @}
*/
#endif /* AVFILTER_BUFFERSINK_H */
|