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
|
/*
* Copyright © 2014 Mozilla Foundation
*
* This program is made available under an ISC-style license. See the
* accompanying file LICENSE for details.
*/
#ifndef CUBEB_RESAMPLER_H
#define CUBEB_RESAMPLER_H
#include "cubeb/cubeb.h"
#if defined(__cplusplus)
extern "C" {
#endif
typedef struct cubeb_resampler cubeb_resampler;
typedef enum {
CUBEB_RESAMPLER_QUALITY_VOIP,
CUBEB_RESAMPLER_QUALITY_DEFAULT,
CUBEB_RESAMPLER_QUALITY_DESKTOP
} cubeb_resampler_quality;
/**
* Create a resampler to adapt the requested sample rate into something that
* is accepted by the audio backend.
* @param stream A cubeb_stream instance supplied to the data callback.
* @param input_params Used to calculate bytes per frame and buffer size for
* resampling of the input side of the stream. NULL if input should not be
* resampled.
* @param output_params Used to calculate bytes per frame and buffer size for
* resampling of the output side of the stream. NULL if output should not be
* resampled.
* @param target_rate The sampling rate after resampling for the input side of
* the stream, and/or the sampling rate prior to resampling of the output side
* of the stream.
* @param callback A callback to request data for resampling.
* @param user_ptr User data supplied to the data callback.
* @param quality Quality of the resampler.
* @retval A non-null pointer if success.
*/
cubeb_resampler * cubeb_resampler_create(cubeb_stream * stream,
cubeb_stream_params * input_params,
cubeb_stream_params * output_params,
unsigned int target_rate,
cubeb_data_callback callback,
void * user_ptr,
cubeb_resampler_quality quality);
/**
* Fill the buffer with frames acquired using the data callback. Resampling will
* happen if necessary.
* @param resampler A cubeb_resampler instance.
* @param input_buffer A buffer of input samples
* @param input_frame_count The size of the buffer. Returns the number of frames
* consumed.
* @param output_buffer The buffer to be filled.
* @param output_frames_needed Number of frames that should be produced.
* @retval Number of frames that are actually produced.
* @retval CUBEB_ERROR on error.
*/
long cubeb_resampler_fill(cubeb_resampler * resampler,
void * input_buffer,
long * input_frame_count,
void * output_buffer,
long output_frames_needed);
/**
* Destroy a cubeb_resampler.
* @param resampler A cubeb_resampler instance.
*/
void cubeb_resampler_destroy(cubeb_resampler * resampler);
/**
* Returns the latency, in frames, of the resampler.
* @param resampler A cubeb resampler instance.
* @retval The latency, in frames, induced by the resampler.
*/
long cubeb_resampler_latency(cubeb_resampler * resampler);
#if defined(__cplusplus)
}
#endif
#endif /* CUBEB_RESAMPLER_H */
|