我试图对视频曲目应用新的约束，但它不起作用：
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title></title>
</head>
<body onload="onLoad();">
<p id="res1"></p>
<p id="res2"></p>
<script>
async function onLoad() {
var opts1 = {audio: true, video: {advanced: [{ width: 1280, height: 960 },]}};
var stream = await navigator.mediaDevices.getUserMedia(opts1);
var cstr1 = stream.getVideoTracks()[0].getSettings();
document.getElementById("res1").innerHTML = cstr1.width + ", " + cstr1.height;
var opts2 = {audio: true, video: {advanced: [{ width: 640, height: 480 },]}};
await stream.getVideoTracks()[0].applyConstraints(opts2);
cstr2 = stream.getVideoTracks()[0].getSettings();
document.getElementById("res2").innerHTML = cstr2.width + ", " + cstr2.height;
}
</script>
</body>
</html>我希望在应用约束之前得到“1280960”，在应用约束之后得到“640480”。但我看到的是“1280960”。为什么？如何正确应用它？
暂无答案！
目前还没有任何答案，快来回答吧！