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
|
/*
* Copyright 2010 Phil Burk, Mobileer Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.jsyn.data;
import com.jsyn.unitgen.FixedRateMonoReader;
import com.jsyn.unitgen.FixedRateStereoReader;
import com.jsyn.unitgen.VariableRateMonoReader;
import com.jsyn.unitgen.VariableRateStereoReader;
import com.jsyn.util.SampleLoader;
/**
* Store multi-channel floating point audio data in an interleaved buffer. The values are stored as
* 32-bit floats. You can play samples using one of the readers, for example VariableRateMonoReader.
*
* @author Phil Burk (C) 2010 Mobileer Inc
* @see SampleLoader
* @see FixedRateMonoReader
* @see FixedRateStereoReader
* @see VariableRateMonoReader
* @see VariableRateStereoReader
*/
public class FloatSample extends AudioSample implements Function {
private float[] buffer;
public FloatSample() {
}
/** Constructor for mono samples. */
public FloatSample(int numFrames) {
this(numFrames, 1);
}
/** Constructor for mono samples with data. */
public FloatSample(float[] data) {
this(data.length, 1);
write(data);
}
/** Constructor for multi-channel samples with data. */
public FloatSample(float[] data, int channelsPerFrame) {
this(data.length / channelsPerFrame, channelsPerFrame);
write(data);
}
/**
* Create a silent sample with enough memory to hold the audio data. The number of sample
* numbers in the array will be numFrames*channelsPerFrame.
*
* @param numFrames number of sample groups. A stereo frame contains 2 samples.
* @param channelsPerFrame 1 for mono, 2 for stereo
*/
public FloatSample(int numFrames, int channelsPerFrame) {
allocate(numFrames, channelsPerFrame);
}
/**
* Allocate memory to hold the audio data. The number of sample numbers in the array will be
* numFrames*channelsPerFrame.
*
* @param numFrames number of sample groups. A stereo frame contains 2 samples.
* @param channelsPerFrame 1 for mono, 2 for stereo
*/
@Override
public void allocate(int numFrames, int channelsPerFrame) {
buffer = new float[numFrames * channelsPerFrame];
this.numFrames = numFrames;
this.channelsPerFrame = channelsPerFrame;
}
/**
* Note that in a stereo sample, a frame has two values.
*
* @param startFrame index of frame in the sample
* @param data data to be written
* @param startIndex index of first value in array
* @param numFrames
*/
public void write(int startFrame, float[] data, int startIndex, int numFrames) {
int numSamplesToWrite = numFrames * channelsPerFrame;
int firstSampleIndexToWrite = startFrame * channelsPerFrame;
System.arraycopy(data, startIndex, buffer, firstSampleIndexToWrite, numSamplesToWrite);
}
/**
* Note that in a stereo sample, a frame has two values.
*
* @param startFrame index of frame in the sample
* @param data array to receive the data from the sample
* @param startIndex index of first location in array to start filling
* @param numFrames
*/
public void read(int startFrame, float[] data, int startIndex, int numFrames) {
int numSamplesToRead = numFrames * channelsPerFrame;
int firstSampleIndexToRead = startFrame * channelsPerFrame;
System.arraycopy(buffer, firstSampleIndexToRead, data, startIndex, numSamplesToRead);
}
/**
* Write the entire array to the sample. The sample data must have already been allocated with
* enough room to contain the data.
*
* @param data
*/
public void write(float[] data) {
write(0, data, 0, data.length / getChannelsPerFrame());
}
public void read(float[] data) {
read(0, data, 0, data.length / getChannelsPerFrame());
}
@Override
public double readDouble(int index) {
return buffer[index];
}
@Override
public void writeDouble(int index, double value) {
buffer[index] = (float) value;
}
/**
* Interpolate between two adjacent samples.
* Note that this will only work for mono, single channel samples.
*
* @param fractionalIndex must be >=0 and < (size-1)
*/
public double interpolate(double fractionalIndex) {
int index = (int) fractionalIndex;
float phase = (float) (fractionalIndex - index);
float source = buffer[index];
float target = buffer[index + 1];
return ((target - source) * phase) + source;
}
/**
* Note that this will only work for mono, single channel samples.
*/
@Override
public double evaluate(double input) {
// Input ranges from -1 to +1
// Map it to range of sample with guard point.
double normalizedInput = (input + 1.0) * 0.5;
// Clip so it does not go out of range of the sample.
if (normalizedInput < 0.0) normalizedInput = 0.0;
else if (normalizedInput > 1.0) normalizedInput = 1.0;
double fractionalIndex = (getNumFrames() - 1.01) * normalizedInput;
return interpolate(fractionalIndex);
}
}
|
