summaryrefslogtreecommitdiff
path: root/libavfilter/buffersrc.h
blob: dcea3da79bad969fc314424589139ed207ccae54 (plain)
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
/*
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVFILTER_BUFFERSRC_H
#define AVFILTER_BUFFERSRC_H

/**
 * @file
 * @ingroup lavfi_buffersrc
 * Memory buffer source API.
 */

#include "avfilter.h"

/**
 * @defgroup lavfi_buffersrc Buffer source API
 * @ingroup lavfi
 * @{
 */

/**
 * This structure contains the parameters describing the frames that will be
 * passed to this filter.
 *
 * It should be allocated with av_buffersrc_parameters_alloc() and freed with
 * av_free(). All the allocated fields in it remain owned by the caller.
 */
typedef struct AVBufferSrcParameters {
    /**
     * video: the pixel format, value corresponds to enum AVPixelFormat
     * audio: the sample format, value corresponds to enum AVSampleFormat
     */
    int format;
    /**
     * The timebase to be used for the timestamps on the input frames.
     */
    AVRational time_base;

    /**
     * Video only, the display dimensions of the input frames.
     */
    int width, height;

    /**
     * Video only, the sample (pixel) aspect ratio.
     */
    AVRational sample_aspect_ratio;

    /**
     * Video only, the frame rate of the input video. This field must only be
     * set to a non-zero value if input stream has a known constant framerate
     * and should be left at its initial value if the framerate is variable or
     * unknown.
     */
    AVRational frame_rate;

    /**
     * Video with a hwaccel pixel format only. This should be a reference to an
     * AVHWFramesContext instance describing the input frames.
     */
    AVBufferRef *hw_frames_ctx;

    /**
     * Audio only, the audio sampling rate in samples per secon.
     */
    int sample_rate;

    /**
     * Audio only, the audio channel layout
     */
    uint64_t channel_layout;
} AVBufferSrcParameters;

/**
 * Allocate a new AVBufferSrcParameters instance. It should be freed by the
 * caller with av_free().
 */
AVBufferSrcParameters *av_buffersrc_parameters_alloc(void);

/**
 * Initialize the buffersrc or abuffersrc filter with the provided parameters.
 * This function may be called multiple times, the later calls override the
 * previous ones. Some of the parameters may also be set through AVOptions, then
 * whatever method is used last takes precedence.
 *
 * @param ctx an instance of the buffersrc or abuffersrc filter
 * @param param the stream parameters. The frames later passed to this filter
 *              must conform to those parameters. All the allocated fields in
 *              param remain owned by the caller, libavfilter will make internal
 *              copies or references when necessary.
 * @return 0 on success, a negative AVERROR code on failure.
 */
int av_buffersrc_parameters_set(AVFilterContext *ctx, AVBufferSrcParameters *param);

/**
 * Add a frame to the buffer source.
 *
 * @param ctx   an instance of the buffersrc filter
 * @param frame frame to be added. If the frame is reference counted, this
 * function will make a new reference to it. Otherwise the frame data will be
 * copied.
 *
 * @return 0 on success, a negative AVERROR on error
 */
int av_buffersrc_write_frame(AVFilterContext *ctx, const AVFrame *frame);

/**
 * Add a frame to the buffer source.
 *
 * @param ctx   an instance of the buffersrc filter
 * @param frame frame to be added. If the frame is reference counted, this
 * function will take ownership of the reference(s) and reset the frame.
 * Otherwise the frame data will be copied. If this function returns an error,
 * the input frame is not touched.
 *
 * @return 0 on success, a negative AVERROR on error.
 *
 * @note the difference between this function and av_buffersrc_write_frame() is
 * that av_buffersrc_write_frame() creates a new reference to the input frame,
 * while this function takes ownership of the reference passed to it.
 */
int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame);

/**
 * @}
 */

#endif /* AVFILTER_BUFFERSRC_H */