summaryrefslogtreecommitdiff
path: root/libavutil/audio_fifo.h
blob: 8c76388255bfbdf18d41cc6076cd7336ee12a1cf (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
144
145
146
/*
 * Audio FIFO
 * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
 *
 * 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
 */

/**
 * @file
 * Audio FIFO Buffer
 */

#ifndef AVUTIL_AUDIO_FIFO_H
#define AVUTIL_AUDIO_FIFO_H

#include "avutil.h"
#include "fifo.h"
#include "samplefmt.h"

/**
 * @addtogroup lavu_audio
 * @{
 */

/**
 * Context for an Audio FIFO Buffer.
 *
 * - Operates at the sample level rather than the byte level.
 * - Supports multiple channels with either planar or packed sample format.
 * - Automatic reallocation when writing to a full buffer.
 */
typedef struct AVAudioFifo AVAudioFifo;

/**
 * Free an AVAudioFifo.
 *
 * @param af  AVAudioFifo to free
 */
void av_audio_fifo_free(AVAudioFifo *af);

/**
 * Allocate an AVAudioFifo.
 *
 * @param sample_fmt  sample format
 * @param channels    number of channels
 * @param nb_samples  initial allocation size, in samples
 * @return            newly allocated AVAudioFifo, or NULL on error
 */
AVAudioFifo *av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels,
                                 int nb_samples);

/**
 * Reallocate an AVAudioFifo.
 *
 * @param af          AVAudioFifo to reallocate
 * @param nb_samples  new allocation size, in samples
 * @return            0 if OK, or negative AVERROR code on failure
 */
int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples);

/**
 * Write data to an AVAudioFifo.
 *
 * The AVAudioFifo will be reallocated automatically if the available space
 * is less than nb_samples.
 *
 * @see enum AVSampleFormat
 * The documentation for AVSampleFormat describes the data layout.
 *
 * @param af          AVAudioFifo to write to
 * @param data        audio data plane pointers
 * @param nb_samples  number of samples to write
 * @return            number of samples actually written, or negative AVERROR
 *                    code on failure.
 */
int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples);

/**
 * Read data from an AVAudioFifo.
 *
 * @see enum AVSampleFormat
 * The documentation for AVSampleFormat describes the data layout.
 *
 * @param af          AVAudioFifo to read from
 * @param data        audio data plane pointers
 * @param nb_samples  number of samples to read
 * @return            number of samples actually read, or negative AVERROR code
 *                    on failure.
 */
int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples);

/**
 * Drain data from an AVAudioFifo.
 *
 * Removes the data without reading it.
 *
 * @param af          AVAudioFifo to drain
 * @param nb_samples  number of samples to drain
 * @return            0 if OK, or negative AVERROR code on failure
 */
int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples);

/**
 * Reset the AVAudioFifo buffer.
 *
 * This empties all data in the buffer.
 *
 * @param af  AVAudioFifo to reset
 */
void av_audio_fifo_reset(AVAudioFifo *af);

/**
 * Get the current number of samples in the AVAudioFifo available for reading.
 *
 * @param af  the AVAudioFifo to query
 * @return    number of samples available for reading
 */
int av_audio_fifo_size(AVAudioFifo *af);

/**
 * Get the current number of samples in the AVAudioFifo available for writing.
 *
 * @param af  the AVAudioFifo to query
 * @return    number of samples available for writing
 */
int av_audio_fifo_space(AVAudioFifo *af);

/**
 * @}
 */

#endif /* AVUTIL_AUDIO_FIFO_H */