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// Shared by the page and the worker, so no DOM access here.
var DEFAULT_ITERATIONS = 30;
var testcases = [];
function registerTestCase(testcase) {
testcases.push(testcase);
}
function runQuery(testcase) {
var mc = navigator.mediaCapabilities;
if (testcase.kind === "encode") {
return mc.encodingInfo(testcase.config);
}
return mc.decodingInfo(testcase.config);
}
async function runOne(testcase) {
var iterations = testcase.iterations || DEFAULT_ITERATIONS;
// Time each query separately and keep the raw values in order, so downstream
// can separate the first query from the rest and still see run-to-run variance.
var values = [];
for (var i = 0; i < iterations; i++) {
var start = performance.now();
try {
await runQuery(testcase);
} catch (e) {
// A malformed contentType rejects (e.g. a container without codecs). Skip
// the case instead of aborting the whole run, and name it so it's fixable.
console.warn("media-capabilities: skipping " + testcase.name + " (" + e + ")");
return null;
}
values.push(performance.now() - start);
}
return { name: testcase.name, values };
}
async function runAll(filter, options) {
options = options || {};
var selected = testcases.filter(function (testcase) {
return !filter || filter(testcase);
});
var results = [];
// The first MediaCapabilities query in a process pays a one-time, process-wide
// init that is independent of the codec and of decode vs encode. Run it once up
// front so it is not charged to whichever testcase runs first. Only the main
// thread reports it: the worker always runs after the page here, so by then the
// process is already warm and a worker number would not reflect that cold cost.
if (selected.length) {
var firstStart = performance.now();
await runQuery(selected[0]);
if (options.recordFirstQuery) {
results.push({
name: "first-query",
values: [performance.now() - firstStart],
});
}
}
for (var i = 0; i < selected.length; i++) {
var result = await runOne(selected[i]);
if (result) {
results.push(result);
}
}
return results;
}