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
|
let sampleRate = 44100.0;
let renderLengthSeconds = 4;
let delayTimeSeconds = 0.5;
let toneLengthSeconds = 2;
function createToneBuffer(context, frequency, numberOfCycles, sampleRate) {
let duration = numberOfCycles / frequency;
let sampleFrameLength = duration * sampleRate;
let audioBuffer = context.createBuffer(1, sampleFrameLength, sampleRate);
let n = audioBuffer.length;
let data = audioBuffer.getChannelData(0);
for (let i = 0; i < n; ++i)
data[i] = Math.sin(frequency * 2.0 * Math.PI * i / sampleRate);
return audioBuffer;
}
function checkDelayedResult(renderedBuffer, toneBuffer, should) {
let sourceData = toneBuffer.getChannelData(0);
let renderedData = renderedBuffer.getChannelData(0);
let delayTimeFrames = delayTimeSeconds * sampleRate;
let toneLengthFrames = toneLengthSeconds * sampleRate;
let success = true;
let n = renderedBuffer.length;
for (let i = 0; i < n; ++i) {
if (i < delayTimeFrames) {
// Check that initial portion is 0 (since signal is delayed).
if (renderedData[i] != 0) {
should(
renderedData[i], 'Initial portion expected to be 0 at frame ' + i)
.beEqualTo(0);
success = false;
break;
}
} else if (i >= delayTimeFrames && i < delayTimeFrames + toneLengthFrames) {
// Make sure that the tone data is delayed by exactly the expected number
// of frames.
let j = i - delayTimeFrames;
if (renderedData[i] != sourceData[j]) {
should(renderedData[i], 'Actual data at frame ' + i)
.beEqualTo(sourceData[j]);
success = false;
break;
}
} else {
// Make sure we have silence after the delayed tone.
if (renderedData[i] != 0) {
should(renderedData[j], 'Final portion at frame ' + i).beEqualTo(0);
success = false;
break;
}
}
}
should(
success, 'Delaying test signal by ' + delayTimeSeconds + ' sec was done')
.message('correctly', 'incorrectly')
}
|
