Fix some bugs & polish edge cases

src/media-sink.ts

@@ -1726,7 +1726,7 @@ const colorAlphaMergerWorkerCode = () => {
 
 		const format = alpha.format;
 		if (format === 'RGBA' || format === 'BGRA' || format === 'RGBX' || format === 'BGRX') {
-			// Pack alpha data tightly
+			// Pack alpha data tightly. Assume alpha is stored in RGB, so sample just from R for simplicity.
 			const rOffset = (format === 'RGBA' || format === 'RGBX') ? 0 : 2;
 			const pixelCount = width * height;
 			for (let i = 0; i < pixelCount; i++) {

src/sample.ts

@@ -1245,8 +1245,9 @@ export class VideoSample implements Disposable {
 			? [this.squarePixelWidth, this.squarePixelHeight]
 			: [this.squarePixelHeight, this.squarePixelWidth];
 
-		if (options.crop) {
-			clampCropRectangle(options.crop, rotatedWidth, rotatedHeight);
+		let finalCrop = options.crop;
+		if (finalCrop) {
+			finalCrop = clampCropRectangle(finalCrop, rotatedWidth, rotatedHeight);
 		}
 
 		// These variables specify where the final sample will be drawn on the canvas

src/source.ts

@@ -591,11 +591,13 @@ const DEFAULT_RETRY_DELAY
 		// Check if this could be a CORS error. If so, we cannot recover from it and
 		// should not attempt to retry.
 		// CORS errors are intentionally not opaque, so we need to rely on heuristics.
-		const couldBeCorsError = error instanceof Error && (
-			error.message.includes('Failed to fetch') // Chrome
-			|| error.message.includes('Load failed') // Safari
-			|| error.message.includes('NetworkError when attempting to fetch resource') // Firefox
-		);
+		const couldBeCorsError = error instanceof Error
+			&& (
+				error.message.includes('Failed to fetch') // Chrome
+				|| error.message.includes('Load failed') // Safari
+				|| error.message.includes('NetworkError when attempting to fetch resource') // Firefox
+			)
+			&& typeof window !== 'undefined'; // CORS only happens in browser environments
 
 		if (couldBeCorsError) {
 			let originOfSrc: string | null = null;