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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* import-globals-from ../webaudio/test/webaudio.js */
"use strict";
async function measureRMSOnceWithFreshScriptProcessor(ac, src) {
const sp = ac.createScriptProcessor(2048, 1, 1);
src.connect(sp);
sp.connect(ac.destination);
const { inputBuffer } = await new Promise(
resolve => (sp.onaudioprocess = resolve)
);
src.disconnect(sp);
sp.disconnect();
sp.onaudioprocess = null;
return rms(inputBuffer);
}
async function waitForRmsPredicate(
ac,
src,
threshold,
predicate,
timeoutMs = 10000
) {
const start = performance.now();
while (true) {
const measuredRms = await measureRMSOnceWithFreshScriptProcessor(ac, src);
if (predicate(measuredRms)) {
return measuredRms;
}
if (performance.now() - start > timeoutMs) {
throw new Error(
`Timed out waiting for RMS threshold ${threshold}; ` +
`last RMS=${measuredRms}`
);
}
}
}
function waitForRmsEqualToThreshold(ac, src, threshold) {
return waitForRmsPredicate(
ac,
src,
threshold,
measuredRms => measuredRms === threshold
);
}
function waitForRmsOverThreshold(ac, src, threshold) {
return waitForRmsPredicate(
ac,
src,
threshold,
measuredRms => measuredRms > threshold
);
}
const RMSUtils = {
measureRMSOnceWithFreshScriptProcessor,
waitForRmsEqualToThreshold,
waitForRmsOverThreshold,
};