codec support check

webroot/js/player.js

@@ -110,8 +110,33 @@ window.addEventListener('DOMContentLoaded', (event) => {
 		}
 	}
 
+	function getMimeType(fmt) {
+		const mainType = fmt.vcodec !== 'none' ? 'video' : 'audio';
+		let secondary = {
+			m4a: 'mp4',
+		}[fmt.ext] || fmt.ext;
+		const codecs = [fmt.vcodec, fmt.acodec].filter(c => c && c !== 'none').join(', ');
+		return `${mainType}/${secondary}; codecs="${codecs}"`;
+	}
+
+	function isFormatSupported(fmt) {
+		if (!['http', 'https'].includes(fmt.protocol))
+			return false;
+
+		// must be very old: https://developer.mozilla.org/en-US/docs/Web/API/MediaSource/isTypeSupported#browser_compatibility
+		if (!('MediaSource' in window)) {
+			if (['avc1', 'none'].includes(fmt.vcodec.substring(0, 4))
+				&& ['mp4a', 'none'].includes(fmt.acodec.substring(0, 4))) {
+				return true;
+			}
+			return false;
+		}
+
+		return MediaSource.isTypeSupported(getMimeType(fmt));
+	}
+
 	const formats = JSON.parse(document.getElementById('yt_formats').innerText)
-		.filter((fmt) => ['http', 'https'].includes(fmt.protocol))
+		.filter((fmt) => isFormatSupported(fmt) === true)
 		.sort((a, b) => {
 			if (a.vcodec === 'none' && b.vcodec !== 'none') {
 				return -1;