feat(export): allow re-saving exported video on dialog cancel

Improve timeline navigation while scrubbing and scrolling

.nvmrc

@@ -0,0 +1 @@
+22.22.1

package-lock.json

@@ -73,6 +73,10 @@
 				"vite-plugin-electron": "^0.28.6",
 				"vite-plugin-electron-renderer": "^0.14.5",
 				"vitest": "^4.0.16"
+			},
+			"engines": {
+				"node": "22.22.1",
+				"npm": "10.9.4"
 			}
 		},
 		"node_modules/@alloc/quick-lru": {

package.json

@@ -3,6 +3,11 @@
 	"private": true,
 	"version": "1.2.0",
 	"type": "module",
+	"packageManager": "npm@10.9.4",
+	"engines": {
+		"node": "22.22.1",
+		"npm": "10.9.4"
+	},
 	"scripts": {
 		"dev": "vite",
 		"build": "tsc && vite build && electron-builder",

src/App.tsx

@@ -1,6 +1,7 @@
 import { useEffect, useState } from "react";
 import { LaunchWindow } from "./components/launch/LaunchWindow";
 import { SourceSelector } from "./components/launch/SourceSelector";
+import { Toaster } from "./components/ui/sonner";
 import { TooltipProvider } from "./components/ui/tooltip";
 import { ShortcutsConfigDialog } from "./components/video-editor/ShortcutsConfigDialog";
 import VideoEditor from "./components/video-editor/VideoEditor";
@@ -48,5 +49,10 @@ export default function App() {
 		}
 	})();
 
-	return <TooltipProvider>{content}</TooltipProvider>;
+	return (
+		<TooltipProvider>
+			{content}
+			<Toaster theme="dark" className="pointer-events-auto" />
+		</TooltipProvider>
+	);
 }

src/components/launch/LaunchWindow.tsx

@@ -19,6 +19,7 @@ import { RxDragHandleDots2 } from "react-icons/rx";
 import { useAudioLevelMeter } from "../../hooks/useAudioLevelMeter";
 import { useMicrophoneDevices } from "../../hooks/useMicrophoneDevices";
 import { useScreenRecorder } from "../../hooks/useScreenRecorder";
+import { requestCameraAccess } from "../../lib/requestCameraAccess";
 import { formatTimePadded } from "../../utils/timeUtils";
 import { AudioLevelMeter } from "../ui/audio-level-meter";
 import { Tooltip } from "../ui/tooltip";
@@ -110,6 +111,16 @@ export function LaunchWindow() {
 		};
 	}, [recording, recordingStart]);
 
+	useEffect(() => {
+		if (!import.meta.env.DEV) {
+			return;
+		}
+
+		void requestCameraAccess().catch((error) => {
+			console.warn("Failed to trigger camera access request during development:", error);
+		});
+	}, []);
+
 	const [selectedSource, setSelectedSource] = useState("Screen");
 	const [hasSelectedSource, setHasSelectedSource] = useState(false);
 
@@ -251,8 +262,8 @@ export function LaunchWindow() {
 						</button>
 						<button
 							className={`${hudIconBtnClasses} ${webcamEnabled ? "drop-shadow-[0_0_4px_rgba(74,222,128,0.4)]" : ""}`}
-							onClick={() => {
-								void setWebcamEnabled(!webcamEnabled);
+							onClick={async () => {
+								await setWebcamEnabled(!webcamEnabled);
 							}}
 							title={webcamEnabled ? "Disable webcam" : "Enable webcam"}
 						>

src/components/video-editor/SettingsPanel.tsx

@@ -25,10 +25,18 @@ import {
 	AccordionTrigger,
 } from "@/components/ui/accordion";
 import { Button } from "@/components/ui/button";
+import {
+	Select,
+	SelectContent,
+	SelectItem,
+	SelectTrigger,
+	SelectValue,
+} from "@/components/ui/select";
 import { Slider } from "@/components/ui/slider";
 import { Switch } from "@/components/ui/switch";
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
 import { getAssetPath } from "@/lib/assetPath";
+import { WEBCAM_LAYOUT_PRESETS } from "@/lib/compositeLayout";
 import type { ExportFormat, ExportQuality, GifFrameRate, GifSizePreset } from "@/lib/exporter";
 import { GIF_FRAME_RATES, GIF_SIZE_PRESETS } from "@/lib/exporter";
 import { cn } from "@/lib/utils";
@@ -43,6 +51,7 @@ import type {
 	CropRegion,
 	FigureData,
 	PlaybackSpeed,
+	WebcamLayoutPreset,
 	ZoomDepth,
 } from "./types";
 import { SPEED_OPTIONS } from "./types";
@@ -121,6 +130,8 @@ interface SettingsPanelProps {
 	onSaveProject?: () => void;
 	onLoadProject?: () => void;
 	onExport?: () => void;
+	unsavedExport?: { arrayBuffer: ArrayBuffer; fileName: string; format: string } | null;
+	onSaveUnsavedExport?: () => void;
 	selectedAnnotationId?: string | null;
 	annotationRegions?: AnnotationRegion[];
 	onAnnotationContentChange?: (id: string, content: string) => void;
@@ -132,6 +143,9 @@ interface SettingsPanelProps {
 	selectedSpeedValue?: PlaybackSpeed | null;
 	onSpeedChange?: (speed: PlaybackSpeed) => void;
 	onSpeedDelete?: (id: string) => void;
+	hasWebcam?: boolean;
+	webcamLayoutPreset?: WebcamLayoutPreset;
+	onWebcamLayoutPresetChange?: (preset: WebcamLayoutPreset) => void;
 }
 
 export default SettingsPanel;
@@ -186,6 +200,8 @@ export function SettingsPanel({
 	onSaveProject,
 	onLoadProject,
 	onExport,
+	unsavedExport,
+	onSaveUnsavedExport,
 	selectedAnnotationId,
 	annotationRegions = [],
 	onAnnotationContentChange,
@@ -197,6 +213,9 @@ export function SettingsPanel({
 	selectedSpeedValue,
 	onSpeedChange,
 	onSpeedDelete,
+	hasWebcam = false,
+	webcamLayoutPreset = "picture-in-picture",
+	onWebcamLayoutPresetChange,
 }: SettingsPanelProps) {
 	const [wallpaperPaths, setWallpaperPaths] = useState<string[]>([]);
 	const [customImages, setCustomImages] = useState<string[]>([]);
@@ -567,7 +586,47 @@ export function SettingsPanel({
 					)}
 				</div>
 
-				<Accordion type="multiple" defaultValue={["effects", "background"]} className="space-y-1">
+				<Accordion
+					type="multiple"
+					defaultValue={hasWebcam ? ["layout", "effects", "background"] : ["effects", "background"]}
+					className="space-y-1"
+				>
+					{hasWebcam && (
+						<AccordionItem
+							value="layout"
+							className="border-white/5 rounded-xl bg-white/[0.02] px-3"
+						>
+							<AccordionTrigger className="py-2.5 hover:no-underline">
+								<div className="flex items-center gap-2">
+									<Sparkles className="w-4 h-4 text-[#34B27B]" />
+									<span className="text-xs font-medium">Layout</span>
+								</div>
+							</AccordionTrigger>
+							<AccordionContent className="pb-3">
+								<div className="p-2 rounded-lg bg-white/5 border border-white/5">
+									<div className="text-[10px] font-medium text-slate-300 mb-1.5">Preset</div>
+									<Select
+										value={webcamLayoutPreset}
+										onValueChange={(value: WebcamLayoutPreset) =>
+											onWebcamLayoutPresetChange?.(value)
+										}
+									>
+										<SelectTrigger className="h-8 bg-black/20 border-white/10 text-xs">
+											<SelectValue placeholder="Select preset" />
+										</SelectTrigger>
+										<SelectContent>
+											{WEBCAM_LAYOUT_PRESETS.map((preset) => (
+												<SelectItem key={preset.value} value={preset.value} className="text-xs">
+													{preset.label}
+												</SelectItem>
+											))}
+										</SelectContent>
+									</Select>
+								</div>
+							</AccordionContent>
+						</AccordionItem>
+					)}
+
 					<AccordionItem value="effects" className="border-white/5 rounded-xl bg-white/[0.02] px-3">
 						<AccordionTrigger className="py-2.5 hover:no-underline">
 							<div className="flex items-center gap-2">
@@ -1095,6 +1154,17 @@ export function SettingsPanel({
 					</Button>
 				</div>
 
+				{unsavedExport && (
+					<Button
+						type="button"
+						size="lg"
+						onClick={onSaveUnsavedExport}
+						className="w-full mb-2 py-5 text-sm font-semibold flex items-center justify-center gap-2 bg-indigo-500 text-white rounded-xl shadow-lg shadow-indigo-500/20 hover:bg-indigo-500/90 hover:scale-[1.02] active:scale-[0.98] transition-all duration-200"
+					>
+						<Download className="w-4 h-4" />
+						Choose Save Location
+					</Button>
+				)}
 				<Button
 					data-testid={getTestId("export-button")}
 					type="button"

src/components/video-editor/VideoEditor.tsx

@@ -2,7 +2,6 @@ import type { Span } from "dnd-timeline";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { Panel, PanelGroup, PanelResizeHandle } from "react-resizable-panels";
 import { toast } from "sonner";
-import { Toaster } from "@/components/ui/sonner";
 import { useShortcuts } from "@/contexts/ShortcutsContext";
 import { INITIAL_EDITOR_STATE, useEditorHistory } from "@/hooks/useEditorHistory";
 import {
@@ -76,6 +75,7 @@ export default function VideoEditor() {
 		borderRadius,
 		padding,
 		aspectRatio,
+		webcamLayoutPreset,
 	} = editorState;
 
 	// ── Non-undoable state
@@ -105,6 +105,11 @@ export default function VideoEditor() {
 	const [gifSizePreset, setGifSizePreset] = useState<GifSizePreset>("medium");
 	const [exportedFilePath, setExportedFilePath] = useState<string | null>(null);
 	const [lastSavedSnapshot, setLastSavedSnapshot] = useState<string | null>(null);
+	const [unsavedExport, setUnsavedExport] = useState<{
+		arrayBuffer: ArrayBuffer;
+		fileName: string;
+		format: string;
+	} | null>(null);
 
 	const videoPlaybackRef = useRef<VideoPlaybackRef>(null);
 	const nextZoomIdRef = useRef(1);
@@ -173,6 +178,7 @@ export default function VideoEditor() {
 				speedRegions: normalizedEditor.speedRegions,
 				annotationRegions: normalizedEditor.annotationRegions,
 				aspectRatio: normalizedEditor.aspectRatio,
+				webcamLayoutPreset: normalizedEditor.webcamLayoutPreset,
 			});
 			setExportQuality(normalizedEditor.exportQuality);
 			setExportFormat(normalizedEditor.exportFormat);
@@ -240,6 +246,7 @@ export default function VideoEditor() {
 				speedRegions,
 				annotationRegions,
 				aspectRatio,
+				webcamLayoutPreset,
 				exportQuality,
 				exportFormat,
 				gifFrameRate,
@@ -261,6 +268,7 @@ export default function VideoEditor() {
 		speedRegions,
 		annotationRegions,
 		aspectRatio,
+		webcamLayoutPreset,
 		exportQuality,
 		exportFormat,
 		gifFrameRate,
@@ -352,6 +360,7 @@ export default function VideoEditor() {
 				speedRegions,
 				annotationRegions,
 				aspectRatio,
+				webcamLayoutPreset,
 				exportQuality,
 				exportFormat,
 				gifFrameRate,
@@ -404,6 +413,7 @@ export default function VideoEditor() {
 			speedRegions,
 			annotationRegions,
 			aspectRatio,
+			webcamLayoutPreset,
 			exportQuality,
 			exportFormat,
 			gifFrameRate,
@@ -961,6 +971,27 @@ export default function VideoEditor() {
 		[handleShowExportedFile],
 	);
 
+	const handleSaveUnsavedExport = useCallback(async () => {
+		if (!unsavedExport) return;
+		try {
+			const saveResult = await window.electronAPI.saveExportedVideo(
+				unsavedExport.arrayBuffer,
+				unsavedExport.fileName,
+			);
+			if (saveResult.canceled) {
+				toast.info("Export canceled");
+			} else if (saveResult.success && saveResult.path) {
+				setUnsavedExport(null);
+				handleExportSaved(unsavedExport.format === "gif" ? "GIF" : "Video", saveResult.path);
+			} else {
+				toast.error(saveResult.message || "Failed to save export");
+			}
+		} catch (error) {
+			console.error("Error saving unsaved export:", error);
+			toast.error("Failed to save exported video");
+		}
+	}, [unsavedExport, handleExportSaved]);
+
 	const handleExport = useCallback(
 		async (settings: ExportSettings) => {
 			if (!videoPath) {
@@ -1021,6 +1052,7 @@ export default function VideoEditor() {
 						videoPadding: padding,
 						cropRegion,
 						annotationRegions,
+						webcamLayoutPreset,
 						previewWidth,
 						previewHeight,
 						onProgress: (progress: ExportProgress) => {
@@ -1039,8 +1071,10 @@ export default function VideoEditor() {
 						const saveResult = await window.electronAPI.saveExportedVideo(arrayBuffer, fileName);
 
 						if (saveResult.canceled) {
+							setUnsavedExport({ arrayBuffer, fileName, format: "gif" });
 							toast.info("Export canceled");
 						} else if (saveResult.success && saveResult.path) {
+							setUnsavedExport(null);
 							handleExportSaved("GIF", saveResult.path);
 						} else {
 							setExportError(saveResult.message || "Failed to save GIF");
@@ -1148,6 +1182,7 @@ export default function VideoEditor() {
 						padding,
 						cropRegion,
 						annotationRegions,
+						webcamLayoutPreset,
 						previewWidth,
 						previewHeight,
 						onProgress: (progress: ExportProgress) => {
@@ -1166,8 +1201,10 @@ export default function VideoEditor() {
 						const saveResult = await window.electronAPI.saveExportedVideo(arrayBuffer, fileName);
 
 						if (saveResult.canceled) {
+							setUnsavedExport({ arrayBuffer, fileName, format: "mp4" });
 							toast.info("Export canceled");
 						} else if (saveResult.success && saveResult.path) {
+							setUnsavedExport(null);
 							handleExportSaved("Video", saveResult.path);
 						} else {
 							setExportError(saveResult.message || "Failed to save video");
@@ -1212,6 +1249,7 @@ export default function VideoEditor() {
 			annotationRegions,
 			isPlaying,
 			aspectRatio,
+			webcamLayoutPreset,
 			exportQuality,
 			handleExportSaved,
 		],
@@ -1351,6 +1389,7 @@ export default function VideoEditor() {
 												ref={videoPlaybackRef}
 												videoPath={videoPath || ""}
 												webcamVideoPath={webcamVideoPath || undefined}
+												webcamLayoutPreset={webcamLayoutPreset}
 												onDurationChange={setDuration}
 												onTimeUpdate={setCurrentTime}
 												currentTime={currentTime}
@@ -1474,6 +1513,9 @@ export default function VideoEditor() {
 							cropRegion={cropRegion}
 							onCropChange={(r) => pushState({ cropRegion: r })}
 							aspectRatio={aspectRatio}
+							hasWebcam={Boolean(webcamVideoPath)}
+							webcamLayoutPreset={webcamLayoutPreset}
+							onWebcamLayoutPresetChange={(preset) => pushState({ webcamLayoutPreset: preset })}
 							videoElement={videoPlaybackRef.current?.video || null}
 							exportQuality={exportQuality}
 							onExportQualityChange={setExportQuality}
@@ -1516,13 +1558,13 @@ export default function VideoEditor() {
 							}
 							onSpeedChange={handleSpeedChange}
 							onSpeedDelete={handleSpeedDelete}
+							unsavedExport={unsavedExport}
+							onSaveUnsavedExport={handleSaveUnsavedExport}
 						/>
 					</Panel>
 				</PanelGroup>
 			</div>
 
-			<Toaster theme="dark" className="pointer-events-auto" />
-
 			<ExportDialog
 				isOpen={showExportDialog}
 				onClose={() => setShowExportDialog(false)}

src/components/video-editor/VideoPlayback.tsx

@@ -19,7 +19,12 @@ import {
 	useState,
 } from "react";
 import { getAssetPath } from "@/lib/assetPath";
-import { computeWebcamOverlayLayout, type WebcamOverlayLayout } from "@/lib/webcamOverlay";
+import {
+	getWebcamLayoutCssBoxShadow,
+	type Size,
+	type StyledRenderRect,
+	type WebcamLayoutPreset,
+} from "@/lib/compositeLayout";
 import {
 	type AspectRatio,
 	formatAspectRatioForCSS,
@@ -57,6 +62,7 @@ import {
 interface VideoPlaybackProps {
 	videoPath: string;
 	webcamVideoPath?: string;
+	webcamLayoutPreset: WebcamLayoutPreset;
 	onDurationChange: (duration: number) => void;
 	onTimeUpdate: (time: number) => void;
 	currentTime: number;
@@ -101,6 +107,7 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 		{
 			videoPath,
 			webcamVideoPath,
+			webcamLayoutPreset,
 			onDurationChange,
 			onTimeUpdate,
 			currentTime,
@@ -134,7 +141,6 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 		const videoRef = useRef<HTMLVideoElement | null>(null);
 		const webcamVideoRef = useRef<HTMLVideoElement | null>(null);
 		const containerRef = useRef<HTMLDivElement | null>(null);
-		const stageRef = useRef<HTMLDivElement | null>(null);
 		const appRef = useRef<Application | null>(null);
 		const videoSpriteRef = useRef<Sprite | null>(null);
 		const videoContainerRef = useRef<Container | null>(null);
@@ -144,11 +150,8 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 		const [videoReady, setVideoReady] = useState(false);
 		const overlayRef = useRef<HTMLDivElement | null>(null);
 		const focusIndicatorRef = useRef<HTMLDivElement | null>(null);
-		const [webcamLayout, setWebcamLayout] = useState<WebcamOverlayLayout | null>(null);
-		const [webcamDimensions, setWebcamDimensions] = useState<{
-			width: number;
-			height: number;
-		} | null>(null);
+		const [webcamLayout, setWebcamLayout] = useState<StyledRenderRect | null>(null);
+		const [webcamDimensions, setWebcamDimensions] = useState<Size | null>(null);
 		const currentTimeRef = useRef(0);
 		const zoomRegionsRef = useRef<ZoomRegion[]>([]);
 		const selectedZoomIdRef = useRef<string | null>(null);
@@ -258,6 +261,8 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 				lockedVideoDimensions: lockedVideoDimensionsRef.current,
 				borderRadius,
 				padding,
+				webcamDimensions,
+				webcamLayoutPreset,
 			});
 
 			if (result) {
@@ -267,6 +272,7 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 				baseOffsetRef.current = result.baseOffset;
 				baseMaskRef.current = result.maskRect;
 				cropBoundsRef.current = result.cropBounds;
+				setWebcamLayout(result.webcamRect);
 
 				// Reset camera container to identity
 				cameraContainer.scale.set(1);
@@ -279,7 +285,14 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 
 				updateOverlayForRegion(activeRegion);
 			}
-		}, [updateOverlayForRegion, cropRegion, borderRadius, padding]);
+		}, [
+			updateOverlayForRegion,
+			cropRegion,
+			borderRadius,
+			padding,
+			webcamDimensions,
+			webcamLayoutPreset,
+		]);
 
 		useEffect(() => {
 			layoutVideoContentRef.current = layoutVideoContent;
@@ -910,6 +923,10 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 		};
 
 		const [resolvedWallpaper, setResolvedWallpaper] = useState<string | null>(null);
+		const webcamCssBoxShadow = useMemo(
+			() => getWebcamLayoutCssBoxShadow(webcamLayoutPreset),
+			[webcamLayoutPreset],
+		);
 
 		useEffect(() => {
 			const webcamVideo = webcamVideoRef.current;
@@ -934,34 +951,6 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 			};
 		}, [webcamVideoPath]);
 
-		useEffect(() => {
-			const stage = stageRef.current;
-			if (!stage || !webcamDimensions) {
-				setWebcamLayout(null);
-				return;
-			}
-
-			const updateLayout = () => {
-				const layout = computeWebcamOverlayLayout({
-					stageWidth: stage.clientWidth,
-					stageHeight: stage.clientHeight,
-					videoWidth: webcamDimensions.width,
-					videoHeight: webcamDimensions.height,
-				});
-				setWebcamLayout(layout);
-			};
-
-			updateLayout();
-
-			if (typeof ResizeObserver === "undefined") {
-				return;
-			}
-
-			const observer = new ResizeObserver(updateLayout);
-			observer.observe(stage);
-			return () => observer.disconnect();
-		}, [webcamDimensions]);
-
 		useEffect(() => {
 			const webcamVideo = webcamVideoRef.current;
 			if (!webcamVideo || !webcamVideoPath) {
@@ -1075,7 +1064,6 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 
 		return (
 			<div
-				ref={stageRef}
 				className="relative rounded-sm overflow-hidden"
 				style={{
 					width: "100%",
@@ -1120,7 +1108,7 @@ const VideoPlayback = forwardRef<VideoPlaybackRef, VideoPlaybackProps>(
 							width: webcamLayout?.width ?? 0,
 							height: webcamLayout?.height ?? 0,
 							borderRadius: webcamLayout?.borderRadius ?? 0,
-							boxShadow: "0 12px 36px rgba(0,0,0,0.35), 0 4px 12px rgba(0,0,0,0.22)",
+							boxShadow: webcamCssBoxShadow,
 							zIndex: 20,
 							opacity: webcamLayout ? 1 : 0,
 							backgroundColor: "#000",

src/components/video-editor/projectPersistence.test.ts

@@ -39,6 +39,7 @@ describe("projectPersistence media compatibility", () => {
 				speedRegions: [],
 				annotationRegions: [],
 				aspectRatio: "16:9",
+				webcamLayoutPreset: "picture-in-picture",
 				exportQuality: "good",
 				exportFormat: "mp4",
 				gifFrameRate: 15,

src/components/video-editor/projectPersistence.ts

@@ -11,9 +11,11 @@ import {
 	DEFAULT_CROP_REGION,
 	DEFAULT_FIGURE_DATA,
 	DEFAULT_PLAYBACK_SPEED,
+	DEFAULT_WEBCAM_LAYOUT_PRESET,
 	DEFAULT_ZOOM_DEPTH,
 	type SpeedRegion,
 	type TrimRegion,
+	type WebcamLayoutPreset,
 	type ZoomRegion,
 } from "./types";
 
@@ -39,6 +41,7 @@ export interface ProjectEditorState {
 	speedRegions: SpeedRegion[];
 	annotationRegions: AnnotationRegion[];
 	aspectRatio: AspectRatio;
+	webcamLayoutPreset: WebcamLayoutPreset;
 	exportQuality: ExportQuality;
 	exportFormat: ExportFormat;
 	gifFrameRate: GifFrameRate;
@@ -341,6 +344,11 @@ export function normalizeProjectEditor(editor: Partial<ProjectEditorState>): Pro
 		annotationRegions: normalizedAnnotationRegions,
 		aspectRatio:
 			editor.aspectRatio && validAspectRatios.has(editor.aspectRatio) ? editor.aspectRatio : "16:9",
+		webcamLayoutPreset:
+			editor.webcamLayoutPreset === "vertical-stack" ||
+			editor.webcamLayoutPreset === "picture-in-picture"
+				? editor.webcamLayoutPreset
+				: DEFAULT_WEBCAM_LAYOUT_PRESET,
 		exportQuality:
 			editor.exportQuality === "medium" || editor.exportQuality === "source"
 				? editor.exportQuality

src/components/video-editor/timeline/TimelineEditor.tsx

@@ -169,6 +169,33 @@ function createInitialRange(totalMs: number): Range {
 	return { start: 0, end: FALLBACK_RANGE_MS };
 }
 
+function clampVisibleRange(candidate: Range, totalMs: number): Range {
+	if (totalMs <= 0) {
+		return candidate;
+	}
+
+	const span = Math.max(candidate.end - candidate.start, 1);
+
+	if (span >= totalMs) {
+		return { start: 0, end: totalMs };
+	}
+
+	const start = Math.max(0, Math.min(candidate.start, totalMs - span));
+	return { start, end: start + span };
+}
+
+function normalizeWheelDelta(delta: number, deltaMode: number, pageSizePx: number): number {
+	if (deltaMode === WheelEvent.DOM_DELTA_LINE) {
+		return delta * 16;
+	}
+
+	if (deltaMode === WheelEvent.DOM_DELTA_PAGE) {
+		return delta * pageSizePx;
+	}
+
+	return delta;
+}
+
 function formatTimeLabel(milliseconds: number, intervalMs: number) {
 	const totalSeconds = milliseconds / 1000;
 	const hours = Math.floor(totalSeconds / 3600);
@@ -204,18 +231,21 @@ function PlaybackCursor({
 	currentTimeMs,
 	videoDurationMs,
 	onSeek,
+	onRangeChange,
 	timelineRef,
 	keyframes = [],
 }: {
 	currentTimeMs: number;
 	videoDurationMs: number;
 	onSeek?: (time: number) => void;
+	onRangeChange?: (updater: (previous: Range) => Range) => void;
 	timelineRef: React.RefObject<HTMLDivElement>;
 	keyframes?: { id: string; time: number }[];
 }) {
 	const { sidebarWidth, direction, range, valueToPixels, pixelsToValue } = useTimelineContext();
 	const sideProperty = direction === "rtl" ? "right" : "left";
 	const [isDragging, setIsDragging] = useState(false);
+	const [dragPreviewTimeMs, setDragPreviewTimeMs] = useState<number | null>(null);
 
 	useEffect(() => {
 		if (!isDragging) return;
@@ -225,6 +255,7 @@ function PlaybackCursor({
 
 			const rect = timelineRef.current.getBoundingClientRect();
 			const clickX = e.clientX - rect.left - sidebarWidth;
+			const contentWidth = Math.max(rect.width - sidebarWidth, 1);
 
 			// Allow dragging outside to 0 or max, but clamp the value
 			const relativeMs = pixelsToValue(clickX);
@@ -243,11 +274,51 @@ function PlaybackCursor({
 				absoluteMs = nearbyKeyframe.time;
 			}
 
+			setDragPreviewTimeMs(absoluteMs);
+
+			const visibleMs = range.end - range.start;
+			if (onRangeChange && visibleMs > 0 && videoDurationMs > visibleMs) {
+				const msPerPixel = visibleMs / contentWidth;
+				const overflowLeftPx = Math.max(0, -clickX);
+				const overflowRightPx = Math.max(0, clickX - contentWidth);
+
+				if (overflowLeftPx > 0 && range.start > 0) {
+					const shiftMs = overflowLeftPx * msPerPixel;
+					onRangeChange((previous) => {
+						const nextRange = clampVisibleRange(
+							{
+								start: previous.start - shiftMs,
+								end: previous.end - shiftMs,
+							},
+							videoDurationMs,
+						);
+						return nextRange.start === previous.start && nextRange.end === previous.end
+							? previous
+							: nextRange;
+					});
+				} else if (overflowRightPx > 0 && range.end < videoDurationMs) {
+					const shiftMs = overflowRightPx * msPerPixel;
+					onRangeChange((previous) => {
+						const nextRange = clampVisibleRange(
+							{
+								start: previous.start + shiftMs,
+								end: previous.end + shiftMs,
+							},
+							videoDurationMs,
+						);
+						return nextRange.start === previous.start && nextRange.end === previous.end
+							? previous
+							: nextRange;
+					});
+				}
+			}
+
 			onSeek(absoluteMs / 1000);
 		};
 
 		const handleMouseUp = () => {
 			setIsDragging(false);
+			setDragPreviewTimeMs(null);
 			document.body.style.cursor = "";
 		};
 
@@ -263,6 +334,7 @@ function PlaybackCursor({
 	}, [
 		isDragging,
 		onSeek,
+		onRangeChange,
 		timelineRef,
 		sidebarWidth,
 		range.start,
@@ -272,11 +344,14 @@ function PlaybackCursor({
 		keyframes,
 	]);
 
-	if (videoDurationMs <= 0 || currentTimeMs < 0) {
+	const displayTimeMs =
+		isDragging && dragPreviewTimeMs !== null ? dragPreviewTimeMs : currentTimeMs;
+
+	if (videoDurationMs <= 0 || displayTimeMs < 0) {
 		return null;
 	}
 
-	const clampedTime = Math.min(currentTimeMs, videoDurationMs);
+	const clampedTime = Math.min(displayTimeMs, videoDurationMs);
 
 	if (clampedTime < range.start || clampedTime > range.end) {
 		return null;
@@ -299,6 +374,7 @@ function PlaybackCursor({
 				}}
 				onMouseDown={(e) => {
 					e.stopPropagation(); // Prevent timeline click
+					setDragPreviewTimeMs(currentTimeMs);
 					setIsDragging(true);
 				}}
 			>
@@ -444,6 +520,7 @@ function Timeline({
 	videoDurationMs,
 	currentTimeMs,
 	onSeek,
+	onRangeChange,
 	onSelectZoom,
 	onSelectTrim,
 	onSelectAnnotation,
@@ -458,6 +535,7 @@ function Timeline({
 	videoDurationMs: number;
 	currentTimeMs: number;
 	onSeek?: (time: number) => void;
+	onRangeChange?: (updater: (previous: Range) => Range) => void;
 	onSelectZoom?: (id: string | null) => void;
 	onSelectTrim?: (id: string | null) => void;
 	onSelectAnnotation?: (id: string | null) => void;
@@ -514,6 +592,46 @@ function Timeline({
 		],
 	);
 
+	const handleTimelineWheel = useCallback(
+		(event: React.WheelEvent<HTMLDivElement>) => {
+			if (!onRangeChange || event.ctrlKey || event.metaKey || videoDurationMs <= 0) {
+				return;
+			}
+
+			const visibleMs = range.end - range.start;
+			if (visibleMs <= 0 || videoDurationMs <= visibleMs) {
+				return;
+			}
+
+			const dominantDelta =
+				Math.abs(event.deltaX) > Math.abs(event.deltaY) ? event.deltaX : event.deltaY;
+			if (dominantDelta === 0) {
+				return;
+			}
+
+			event.preventDefault();
+
+			const pageWidthPx = Math.max(event.currentTarget.clientWidth - sidebarWidth, 1);
+			const normalizedDeltaPx = normalizeWheelDelta(dominantDelta, event.deltaMode, pageWidthPx);
+			const shiftMs = pixelsToValue(normalizedDeltaPx);
+
+			onRangeChange((previous) => {
+				const nextRange = clampVisibleRange(
+					{
+						start: previous.start + shiftMs,
+						end: previous.end + shiftMs,
+					},
+					videoDurationMs,
+				);
+
+				return nextRange.start === previous.start && nextRange.end === previous.end
+					? previous
+					: nextRange;
+			});
+		},
+		[onRangeChange, videoDurationMs, range.end, range.start, sidebarWidth, pixelsToValue],
+	);
+
 	const zoomItems = items.filter((item) => item.rowId === ZOOM_ROW_ID);
 	const trimItems = items.filter((item) => item.rowId === TRIM_ROW_ID);
 	const annotationItems = items.filter((item) => item.rowId === ANNOTATION_ROW_ID);
@@ -525,6 +643,7 @@ function Timeline({
 			style={style}
 			className="select-none bg-[#09090b] min-h-[140px] relative cursor-pointer group"
 			onClick={handleTimelineClick}
+			onWheel={handleTimelineWheel}
 		>
 			<div className="absolute inset-0 bg-[linear-gradient(to_right,#ffffff03_1px,transparent_1px)] bg-[length:20px_100%] pointer-events-none" />
 			<TimelineAxis videoDurationMs={videoDurationMs} currentTimeMs={currentTimeMs} />
@@ -532,6 +651,7 @@ function Timeline({
 				currentTimeMs={currentTimeMs}
 				videoDurationMs={videoDurationMs}
 				onSeek={onSeek}
+				onRangeChange={onRangeChange}
 				timelineRef={localTimelineRef}
 				keyframes={keyframes}
 			/>
@@ -657,17 +777,15 @@ export default function TimelineEditor({
 	const [keyframes, setKeyframes] = useState<{ id: string; time: number }[]>([]);
 	const [selectedKeyframeId, setSelectedKeyframeId] = useState<string | null>(null);
 	const [scrollLabels, setScrollLabels] = useState({
-		pan: "Shift + Ctrl + Scroll",
+		pan: "Scroll",
 		zoom: "Ctrl + Scroll",
 	});
 	const timelineContainerRef = useRef<HTMLDivElement>(null);
 	const { shortcuts: keyShortcuts, isMac } = useShortcuts();
 
 	useEffect(() => {
-		formatShortcut(["shift", "mod", "Scroll"]).then((pan) => {
-			formatShortcut(["mod", "Scroll"]).then((zoom) => {
-				setScrollLabels({ pan, zoom });
-			});
+		formatShortcut(["mod", "Scroll"]).then((zoom) => {
+			setScrollLabels({ pan: "Scroll", zoom });
 		});
 	}, []);
 
@@ -1351,6 +1469,7 @@ export default function TimelineEditor({
 						videoDurationMs={totalMs}
 						currentTimeMs={currentTimeMs}
 						onSeek={onSeek}
+						onRangeChange={setRange}
 						onSelectZoom={onSelectZoom}
 						onSelectTrim={onSelectTrim}
 						onSelectAnnotation={onSelectAnnotation}

src/components/video-editor/types.ts

@@ -1,4 +1,9 @@
+import type { WebcamLayoutPreset } from "@/lib/compositeLayout";
+
 export type ZoomDepth = 1 | 2 | 3 | 4 | 5 | 6;
+export type { WebcamLayoutPreset };
+
+export const DEFAULT_WEBCAM_LAYOUT_PRESET: WebcamLayoutPreset = "picture-in-picture";
 
 export interface ZoomFocus {
 	cx: number; // normalized horizontal center (0-1)

src/components/video-editor/videoPlayback/layoutUtils.ts

@@ -1,4 +1,11 @@
 import { Application, Graphics, Sprite } from "pixi.js";
+import {
+	computeCompositeLayout,
+	type RenderRect,
+	type Size,
+	type StyledRenderRect,
+	type WebcamLayoutPreset,
+} from "@/lib/compositeLayout";
 import type { CropRegion } from "../types";
 
 interface LayoutParams {
@@ -11,6 +18,8 @@ interface LayoutParams {
 	lockedVideoDimensions?: { width: number; height: number } | null;
 	borderRadius?: number;
 	padding?: number;
+	webcamDimensions?: Size | null;
+	webcamLayoutPreset?: WebcamLayoutPreset;
 }
 
 interface LayoutResult {
@@ -18,7 +27,8 @@ interface LayoutResult {
 	videoSize: { width: number; height: number };
 	baseScale: number;
 	baseOffset: { x: number; y: number };
-	maskRect: { x: number; y: number; width: number; height: number };
+	maskRect: RenderRect;
+	webcamRect: StyledRenderRect | null;
 	cropBounds: { startX: number; endX: number; startY: number; endY: number };
 }
 
@@ -33,6 +43,8 @@ export function layoutVideoContent(params: LayoutParams): LayoutResult | null {
 		lockedVideoDimensions,
 		borderRadius = 0,
 		padding = 0,
+		webcamDimensions,
+		webcamLayoutPreset,
 	} = params;
 
 	const videoWidth = lockedVideoDimensions?.width || videoElement.videoWidth;
@@ -71,11 +83,19 @@ export function layoutVideoContent(params: LayoutParams): LayoutResult | null {
 	const maxDisplayWidth = width * paddingScale;
 	const maxDisplayHeight = height * paddingScale;
 
-	const scale = Math.min(
-		maxDisplayWidth / croppedVideoWidth,
-		maxDisplayHeight / croppedVideoHeight,
-		1,
-	);
+	const compositeLayout = computeCompositeLayout({
+		canvasSize: { width, height },
+		maxContentSize: { width: maxDisplayWidth, height: maxDisplayHeight },
+		screenSize: { width: croppedVideoWidth, height: croppedVideoHeight },
+		webcamSize: webcamDimensions,
+		layoutPreset: webcamLayoutPreset,
+	});
+
+	if (!compositeLayout) {
+		return null;
+	}
+
+	const scale = compositeLayout.screenRect.width / croppedVideoWidth;
 
 	videoSprite.scale.set(scale);
 
@@ -84,30 +104,25 @@ export function layoutVideoContent(params: LayoutParams): LayoutResult | null {
 	const fullVideoDisplayHeight = videoHeight * scale;
 
 	// Calculate display size of just the cropped region
-	const croppedDisplayWidth = croppedVideoWidth * scale;
-	const croppedDisplayHeight = croppedVideoHeight * scale;
-
-	// Center the cropped region in the container
-	const centerOffsetX = (width - croppedDisplayWidth) / 2;
-	const centerOffsetY = (height - croppedDisplayHeight) / 2;
-
 	// Position the full video sprite so that when we apply the mask,
 	// the cropped region appears centered
 	// The crop starts at (crop.x * videoWidth, crop.y * videoHeight) in video coordinates
 	// In display coordinates, that's (crop.x * fullVideoDisplayWidth, crop.y * fullVideoDisplayHeight)
-	// We want that point to be at centerOffsetX, centerOffsetY
-	const spriteX = centerOffsetX - crop.x * fullVideoDisplayWidth;
-	const spriteY = centerOffsetY - crop.y * fullVideoDisplayHeight;
+	// We want that point to be at screenRect.x, screenRect.y
+	const spriteX = compositeLayout.screenRect.x - crop.x * fullVideoDisplayWidth;
+	const spriteY = compositeLayout.screenRect.y - crop.y * fullVideoDisplayHeight;
 
 	videoSprite.position.set(spriteX, spriteY);
 
-	// Create a mask that only shows the cropped region (centered in container)
-	const maskX = centerOffsetX;
-	const maskY = centerOffsetY;
-
 	// Apply border radius
 	maskGraphics.clear();
-	maskGraphics.roundRect(maskX, maskY, croppedDisplayWidth, croppedDisplayHeight, borderRadius);
+	maskGraphics.roundRect(
+		compositeLayout.screenRect.x,
+		compositeLayout.screenRect.y,
+		compositeLayout.screenRect.width,
+		compositeLayout.screenRect.height,
+		borderRadius,
+	);
 	maskGraphics.fill({ color: 0xffffff });
 
 	return {
@@ -115,7 +130,8 @@ export function layoutVideoContent(params: LayoutParams): LayoutResult | null {
 		videoSize: { width: croppedVideoWidth, height: croppedVideoHeight },
 		baseScale: scale,
 		baseOffset: { x: spriteX, y: spriteY },
-		maskRect: { x: maskX, y: maskY, width: croppedDisplayWidth, height: croppedDisplayHeight },
+		maskRect: compositeLayout.screenRect,
+		webcamRect: compositeLayout.webcamRect,
 		cropBounds: { startX: cropStartX, endX: cropEndX, startY: cropStartY, endY: cropEndY },
 	};
 }

src/hooks/useEditorHistory.ts

@@ -4,9 +4,10 @@ import type {
 	CropRegion,
 	SpeedRegion,
 	TrimRegion,
+	WebcamLayoutPreset,
 	ZoomRegion,
 } from "@/components/video-editor/types";
-import { DEFAULT_CROP_REGION } from "@/components/video-editor/types";
+import { DEFAULT_CROP_REGION, DEFAULT_WEBCAM_LAYOUT_PRESET } from "@/components/video-editor/types";
 import type { AspectRatio } from "@/utils/aspectRatioUtils";
 
 // Undoable state — selection IDs are intentionally excluded (undoing a
@@ -24,6 +25,7 @@ export interface EditorState {
 	borderRadius: number;
 	padding: number;
 	aspectRatio: AspectRatio;
+	webcamLayoutPreset: WebcamLayoutPreset;
 }
 
 export const INITIAL_EDITOR_STATE: EditorState = {
@@ -39,6 +41,7 @@ export const INITIAL_EDITOR_STATE: EditorState = {
 	borderRadius: 0,
 	padding: 50,
 	aspectRatio: "16:9",
+	webcamLayoutPreset: DEFAULT_WEBCAM_LAYOUT_PRESET,
 };
 
 type StateUpdate = Partial<EditorState> | ((prev: EditorState) => Partial<EditorState>);

src/hooks/useScreenRecorder.ts

@@ -1,6 +1,7 @@
 import { fixWebmDuration } from "@fix-webm-duration/fix";
 import { useCallback, useEffect, useRef, useState } from "react";
 import { toast } from "sonner";
+import { requestCameraAccess } from "@/lib/requestCameraAccess";
 
 const TARGET_FRAME_RATE = 60;
 const MIN_FRAME_RATE = 30;
@@ -157,7 +158,7 @@ export function useScreenRecorder(): UseScreenRecorderReturn {
 			return true;
 		}
 
-		const accessResult = await window.electronAPI.requestCameraAccess();
+		const accessResult = await requestCameraAccess();
 		if (!accessResult.success) {
 			toast.error("Failed to request camera access.");
 			return false;
@@ -168,19 +169,8 @@ export function useScreenRecorder(): UseScreenRecorderReturn {
 			return false;
 		}
 
-		try {
-			const probeStream = await navigator.mediaDevices.getUserMedia({
-				audio: false,
-				video: true,
-			});
-			probeStream.getTracks().forEach((track) => track.stop());
-			setWebcamEnabledState(true);
-			return true;
-		} catch (error) {
-			console.warn("Failed to preflight webcam access:", error);
-			toast.error("Camera access denied. Webcam overlay will stay disabled.");
-			return false;
-		}
+		setWebcamEnabledState(true);
+		return true;
 	}, []);
 
 	const finalizeRecording = useCallback(

src/lib/compositeLayout.test.ts

@@ -0,0 +1,78 @@
+import { describe, expect, it } from "vitest";
+import { computeCompositeLayout } from "./compositeLayout";
+
+describe("computeCompositeLayout", () => {
+	it("anchors the overlay in the lower-right corner", () => {
+		const layout = computeCompositeLayout({
+			canvasSize: { width: 1920, height: 1080 },
+			screenSize: { width: 1920, height: 1080 },
+			webcamSize: { width: 1280, height: 720 },
+		});
+
+		expect(layout).not.toBeNull();
+		expect(layout!.webcamRect).not.toBeNull();
+		expect(layout!.webcamRect!.x + layout!.webcamRect!.width).toBeLessThanOrEqual(1920);
+		expect(layout!.webcamRect!.y + layout!.webcamRect!.height).toBeLessThanOrEqual(1080);
+		expect(layout!.webcamRect!.x).toBeGreaterThan(1920 / 2);
+		expect(layout!.webcamRect!.y).toBeGreaterThan(1080 / 2);
+	});
+
+	it("keeps the overlay within the configured stage fraction while preserving aspect ratio", () => {
+		const layout = computeCompositeLayout({
+			canvasSize: { width: 1280, height: 720 },
+			screenSize: { width: 1280, height: 720 },
+			webcamSize: { width: 1920, height: 1080 },
+		});
+
+		expect(layout).not.toBeNull();
+		expect(layout!.webcamRect).not.toBeNull();
+		expect(layout!.webcamRect!.width).toBeLessThanOrEqual(Math.round(1280 * 0.18) + 1);
+		expect(layout!.webcamRect!.height).toBeLessThanOrEqual(Math.round(720 * 0.18) + 1);
+		expect(
+			Math.abs(layout!.webcamRect!.width * 1080 - layout!.webcamRect!.height * 1920),
+		).toBeLessThanOrEqual(1920);
+	});
+
+	it("centers the combined screen and webcam stack in vertical stack mode", () => {
+		const layout = computeCompositeLayout({
+			canvasSize: { width: 1920, height: 1080 },
+			maxContentSize: { width: 1536, height: 864 },
+			screenSize: { width: 1920, height: 1080 },
+			webcamSize: { width: 1280, height: 720 },
+			layoutPreset: "vertical-stack",
+		});
+
+		expect(layout).not.toBeNull();
+		expect(layout?.screenRect).toEqual({
+			x: 576,
+			y: 108,
+			width: 768,
+			height: 432,
+		});
+		expect(layout?.webcamRect).toEqual({
+			x: 576,
+			y: 540,
+			width: 768,
+			height: 432,
+			borderRadius: 0,
+		});
+	});
+
+	it("keeps the screen centered and omits the webcam when dimensions are unavailable", () => {
+		const layout = computeCompositeLayout({
+			canvasSize: { width: 1920, height: 1080 },
+			maxContentSize: { width: 1536, height: 864 },
+			screenSize: { width: 1920, height: 1080 },
+			layoutPreset: "vertical-stack",
+		});
+
+		expect(layout).not.toBeNull();
+		expect(layout?.screenRect).toEqual({
+			x: 192,
+			y: 108,
+			width: 1536,
+			height: 864,
+		});
+		expect(layout?.webcamRect).toBeNull();
+	});
+});

src/lib/compositeLayout.ts

@@ -0,0 +1,250 @@
+export interface RenderRect {
+	x: number;
+	y: number;
+	width: number;
+	height: number;
+}
+
+export interface StyledRenderRect extends RenderRect {
+	borderRadius: number;
+}
+
+export interface Size {
+	width: number;
+	height: number;
+}
+
+export type WebcamLayoutPreset = "picture-in-picture" | "vertical-stack";
+
+export interface WebcamLayoutShadow {
+	color: string;
+	blur: number;
+	offsetX: number;
+	offsetY: number;
+}
+
+interface BorderRadiusRule {
+	max: number;
+	min: number;
+	fraction: number;
+}
+
+interface OverlayTransform {
+	type: "overlay";
+	maxStageFraction: number;
+	marginFraction: number;
+	minMargin: number;
+	minSize: number;
+}
+
+interface StackTransform {
+	type: "stack";
+	gap: number;
+}
+
+export interface WebcamLayoutPresetDefinition {
+	label: string;
+	transform: OverlayTransform | StackTransform;
+	borderRadius: BorderRadiusRule;
+	shadow: WebcamLayoutShadow | null;
+}
+
+export interface WebcamCompositeLayout {
+	screenRect: RenderRect;
+	webcamRect: StyledRenderRect | null;
+}
+
+const MAX_STAGE_FRACTION = 0.18;
+const MARGIN_FRACTION = 0.02;
+const MIN_SIZE = 96;
+const MAX_BORDER_RADIUS = 24;
+const WEBCAM_LAYOUT_PRESET_MAP: Record<WebcamLayoutPreset, WebcamLayoutPresetDefinition> = {
+	"picture-in-picture": {
+		label: "Picture in Picture",
+		transform: {
+			type: "overlay",
+			maxStageFraction: MAX_STAGE_FRACTION,
+			marginFraction: MARGIN_FRACTION,
+			minMargin: 12,
+			minSize: MIN_SIZE,
+		},
+		borderRadius: {
+			max: MAX_BORDER_RADIUS,
+			min: 12,
+			fraction: 0.12,
+		},
+		shadow: {
+			color: "rgba(0,0,0,0.35)",
+			blur: 24,
+			offsetX: 0,
+			offsetY: 10,
+		},
+	},
+	"vertical-stack": {
+		label: "Vertical Stack",
+		transform: {
+			type: "stack",
+			gap: 0,
+		},
+		borderRadius: {
+			max: 0,
+			min: 0,
+			fraction: 0,
+		},
+		shadow: null,
+	},
+};
+
+export const WEBCAM_LAYOUT_PRESETS = Object.entries(WEBCAM_LAYOUT_PRESET_MAP).map(
+	([value, preset]) => ({
+		value: value as WebcamLayoutPreset,
+		label: preset.label,
+	}),
+);
+
+export function getWebcamLayoutPresetDefinition(
+	preset: WebcamLayoutPreset = "picture-in-picture",
+): WebcamLayoutPresetDefinition {
+	return WEBCAM_LAYOUT_PRESET_MAP[preset];
+}
+
+export function getWebcamLayoutCssBoxShadow(
+	preset: WebcamLayoutPreset = "picture-in-picture",
+): string {
+	const shadow = getWebcamLayoutPresetDefinition(preset).shadow;
+	return shadow
+		? `${shadow.offsetX}px ${shadow.offsetY}px ${shadow.blur}px ${shadow.color}`
+		: "none";
+}
+
+export function computeCompositeLayout(params: {
+	canvasSize: Size;
+	maxContentSize?: Size;
+	screenSize: Size;
+	webcamSize?: Size | null;
+	layoutPreset?: WebcamLayoutPreset;
+}): WebcamCompositeLayout | null {
+	const {
+		canvasSize,
+		maxContentSize = canvasSize,
+		screenSize,
+		webcamSize,
+		layoutPreset = "picture-in-picture",
+	} = params;
+	const { width: canvasWidth, height: canvasHeight } = canvasSize;
+	const { width: maxContentWidth, height: maxContentHeight } = maxContentSize;
+	const { width: screenWidth, height: screenHeight } = screenSize;
+	const webcamWidth = webcamSize?.width;
+	const webcamHeight = webcamSize?.height;
+	const preset = getWebcamLayoutPresetDefinition(layoutPreset);
+
+	if (canvasWidth <= 0 || canvasHeight <= 0 || screenWidth <= 0 || screenHeight <= 0) {
+		return null;
+	}
+
+	if (preset.transform.type === "stack") {
+		if (!webcamWidth || !webcamHeight || webcamWidth <= 0 || webcamHeight <= 0) {
+			return {
+				screenRect: centerRect({
+					canvasSize,
+					size: screenSize,
+					maxSize: maxContentSize,
+				}),
+				webcamRect: null,
+			};
+		}
+
+		const gap = preset.transform.gap;
+		const normalizedWebcamHeight = webcamHeight * (screenWidth / webcamWidth);
+		const combinedHeight = screenHeight + gap + normalizedWebcamHeight;
+		const scale = Math.min(maxContentWidth / screenWidth, maxContentHeight / combinedHeight, 1);
+		const clampedScale = Number.isFinite(scale) && scale > 0 ? scale : 1;
+		const resolvedScreenHeight = Math.round(screenHeight * clampedScale);
+		const resolvedScreenWidth = Math.round(screenWidth * clampedScale);
+		const resolvedWebcamHeight = Math.round(normalizedWebcamHeight * clampedScale);
+		const resolvedGap = Math.round(gap * clampedScale);
+		const totalHeight = resolvedScreenHeight + resolvedGap + resolvedWebcamHeight;
+		const top = Math.max(0, Math.floor((canvasHeight - totalHeight) / 2));
+		const left = Math.max(0, Math.floor((canvasWidth - resolvedScreenWidth) / 2));
+		const screenRect = {
+			x: left,
+			y: top,
+			width: resolvedScreenWidth,
+			height: resolvedScreenHeight,
+		};
+
+		return {
+			screenRect,
+			webcamRect: {
+				x: left,
+				y: top + resolvedScreenHeight + resolvedGap,
+				width: resolvedScreenWidth,
+				height: resolvedWebcamHeight,
+				borderRadius: Math.min(
+					preset.borderRadius.max,
+					Math.max(
+						preset.borderRadius.min,
+						Math.round(
+							Math.min(resolvedScreenWidth, resolvedWebcamHeight) * preset.borderRadius.fraction,
+						),
+					),
+				),
+			},
+		};
+	}
+
+	const transform = preset.transform;
+	const screenRect = centerRect({
+		canvasSize,
+		size: screenSize,
+		maxSize: maxContentSize,
+	});
+
+	if (!webcamWidth || !webcamHeight || webcamWidth <= 0 || webcamHeight <= 0) {
+		return { screenRect, webcamRect: null };
+	}
+
+	const margin = Math.max(
+		transform.minMargin,
+		Math.round(Math.min(canvasWidth, canvasHeight) * transform.marginFraction),
+	);
+	const maxWidth = Math.max(transform.minSize, canvasWidth * transform.maxStageFraction);
+	const maxHeight = Math.max(transform.minSize, canvasHeight * transform.maxStageFraction);
+	const scale = Math.min(maxWidth / webcamWidth, maxHeight / webcamHeight);
+	const width = Math.round(webcamWidth * scale);
+	const height = Math.round(webcamHeight * scale);
+
+	return {
+		screenRect,
+		webcamRect: {
+			x: Math.max(0, Math.round(canvasWidth - margin - width)),
+			y: Math.max(0, Math.round(canvasHeight - margin - height)),
+			width,
+			height,
+			borderRadius: Math.min(
+				preset.borderRadius.max,
+				Math.max(
+					preset.borderRadius.min,
+					Math.round(Math.min(width, height) * preset.borderRadius.fraction),
+				),
+			),
+		},
+	};
+}
+
+function centerRect(params: { canvasSize: Size; size: Size; maxSize: Size }): RenderRect {
+	const { canvasSize, size, maxSize } = params;
+	const { width: canvasWidth, height: canvasHeight } = canvasSize;
+	const { width, height } = size;
+	const { width: maxWidth, height: maxHeight } = maxSize;
+	const scale = Math.min(maxWidth / width, maxHeight / height, 1);
+	const resolvedWidth = Math.round(width * scale);
+	const resolvedHeight = Math.round(height * scale);
+
+	return {
+		x: Math.max(0, Math.floor((canvasWidth - resolvedWidth) / 2)),
+		y: Math.max(0, Math.floor((canvasHeight - resolvedHeight) / 2)),
+		width: resolvedWidth,
+		height: resolvedHeight,
+	};
+}

src/lib/exporter/frameRenderer.ts

@@ -12,6 +12,7 @@ import type {
 	AnnotationRegion,
 	CropRegion,
 	SpeedRegion,
+	WebcamLayoutPreset,
 	ZoomDepth,
 	ZoomRegion,
 } from "@/components/video-editor/types";
@@ -30,8 +31,19 @@ import {
 	createMotionBlurState,
 	type MotionBlurState,
 } from "@/components/video-editor/videoPlayback/zoomTransform";
-import { computeWebcamOverlayLayout } from "@/lib/webcamOverlay";
+import {
+	computeCompositeLayout,
+	getWebcamLayoutPresetDefinition,
+	type Size,
+	type StyledRenderRect,
+} from "@/lib/compositeLayout";
 import { renderAnnotations } from "./annotationRenderer";
+import {
+	getLinearGradientPoints,
+	getRadialGradientShape,
+	parseCssGradient,
+	resolveLinearGradientAngle,
+} from "./gradientParser";
 
 interface FrameRenderConfig {
 	width: number;
@@ -47,8 +59,8 @@ interface FrameRenderConfig {
 	cropRegion: CropRegion;
 	videoWidth: number;
 	videoHeight: number;
-	webcamWidth?: number;
-	webcamHeight?: number;
+	webcamSize?: Size | null;
+	webcamLayoutPreset?: WebcamLayoutPreset;
 	annotationRegions?: AnnotationRegion[];
 	speedRegions?: SpeedRegion[];
 	previewWidth?: number;
@@ -71,6 +83,7 @@ interface LayoutCache {
 	baseScale: number;
 	baseOffset: { x: number; y: number };
 	maskRect: { x: number; y: number; width: number; height: number };
+	webcamRect: StyledRenderRect | null;
 }
 
 // Renders video frames with all effects (background, zoom, crop, blur, shadow) to an offscreen canvas for export.
@@ -156,7 +169,9 @@ export class FrameRenderer {
 		this.compositeCanvas = document.createElement("canvas");
 		this.compositeCanvas.width = this.config.width;
 		this.compositeCanvas.height = this.config.height;
-		this.compositeCtx = this.compositeCanvas.getContext("2d", { willReadFrequently: false });
+		this.compositeCtx = this.compositeCanvas.getContext("2d", {
+			willReadFrequently: false,
+		});
 
 		if (!this.compositeCtx) {
 			throw new Error("Failed to get 2D context for composite canvas");
@@ -167,7 +182,9 @@ export class FrameRenderer {
 			this.shadowCanvas = document.createElement("canvas");
 			this.shadowCanvas.width = this.config.width;
 			this.shadowCanvas.height = this.config.height;
-			this.shadowCtx = this.shadowCanvas.getContext("2d", { willReadFrequently: false });
+			this.shadowCtx = this.shadowCanvas.getContext("2d", {
+				willReadFrequently: false,
+			});
 
 			if (!this.shadowCtx) {
 				throw new Error("Failed to get 2D context for shadow canvas");
@@ -248,40 +265,39 @@ export class FrameRenderer {
 				wallpaper.startsWith("linear-gradient") ||
 				wallpaper.startsWith("radial-gradient")
 			) {
-				const gradientMatch = wallpaper.match(/(linear|radial)-gradient\((.+)\)/);
-				if (gradientMatch) {
-					const [, type, params] = gradientMatch;
-					const parts = params.split(",").map((s) => s.trim());
+				const parsedGradient = parseCssGradient(wallpaper);
+				if (parsedGradient) {
+					const gradient =
+						parsedGradient.type === "linear"
+							? (() => {
+									const points = getLinearGradientPoints(
+										resolveLinearGradientAngle(parsedGradient.descriptor),
+										this.config.width,
+										this.config.height,
+									);
 
-					let gradient: CanvasGradient;
+									return bgCtx.createLinearGradient(points.x0, points.y0, points.x1, points.y1);
+								})()
+							: (() => {
+									const shape = getRadialGradientShape(
+										parsedGradient.descriptor,
+										this.config.width,
+										this.config.height,
+									);
 
-					if (type === "linear") {
-						gradient = bgCtx.createLinearGradient(0, 0, 0, this.config.height);
-						parts.forEach((part, index) => {
-							if (part.startsWith("to ") || part.includes("deg")) return;
+									return bgCtx.createRadialGradient(
+										shape.cx,
+										shape.cy,
+										0,
+										shape.cx,
+										shape.cy,
+										shape.radius,
+									);
+								})();
 
-							const colorMatch = part.match(/^(#[0-9a-fA-F]{3,8}|rgba?\([^)]+\)|[a-z]+)/);
-							if (colorMatch) {
-								const color = colorMatch[1];
-								const position = index / (parts.length - 1);
-								gradient.addColorStop(position, color);
-							}
-						});
-					} else {
-						const cx = this.config.width / 2;
-						const cy = this.config.height / 2;
-						const radius = Math.max(this.config.width, this.config.height) / 2;
-						gradient = bgCtx.createRadialGradient(cx, cy, 0, cx, cy, radius);
-
-						parts.forEach((part, index) => {
-							const colorMatch = part.match(/^(#[0-9a-fA-F]{3,8}|rgba?\([^)]+\)|[a-z]+)/);
-							if (colorMatch) {
-								const color = colorMatch[1];
-								const position = index / (parts.length - 1);
-								gradient.addColorStop(position, color);
-							}
-						});
-					}
+					parsedGradient.stops.forEach((stop) => {
+						gradient.addColorStop(stop.offset, stop.color);
+					});
 
 					bgCtx.fillStyle = gradient;
 					bgCtx.fillRect(0, 0, this.config.width, this.config.height);
@@ -329,7 +345,7 @@ export class FrameRenderer {
 		}
 
 		// Apply layout
-		this.updateLayout();
+		this.updateLayout(webcamFrame);
 
 		const timeMs = this.currentVideoTime * 1000;
 		const TICKS_PER_FRAME = 1;
@@ -393,7 +409,7 @@ export class FrameRenderer {
 		}
 	}
 
-	private updateLayout(): void {
+	private updateLayout(webcamFrame?: VideoFrame | null): void {
 		if (!this.app || !this.videoSprite || !this.maskGraphics || !this.videoContainer) return;
 
 		const { width, height } = this.config;
@@ -415,7 +431,16 @@ export class FrameRenderer {
 		const paddingScale = 1.0 - (padding / 100) * 0.4;
 		const viewportWidth = width * paddingScale;
 		const viewportHeight = height * paddingScale;
-		const scale = Math.min(viewportWidth / croppedVideoWidth, viewportHeight / croppedVideoHeight);
+		const compositeLayout = computeCompositeLayout({
+			canvasSize: { width, height },
+			maxContentSize: { width: viewportWidth, height: viewportHeight },
+			screenSize: { width: croppedVideoWidth, height: croppedVideoHeight },
+			webcamSize: webcamFrame ? this.config.webcamSize : null,
+			layoutPreset: this.config.webcamLayoutPreset,
+		});
+		if (!compositeLayout) return;
+
+		const scale = compositeLayout.screenRect.width / croppedVideoWidth;
 
 		// Position video sprite
 		this.videoSprite.width = videoWidth * scale;
@@ -427,12 +452,10 @@ export class FrameRenderer {
 		this.videoSprite.y = -cropPixelY;
 
 		// Position video container
-		const croppedDisplayWidth = croppedVideoWidth * scale;
-		const croppedDisplayHeight = croppedVideoHeight * scale;
-		const centerOffsetX = (width - croppedDisplayWidth) / 2;
-		const centerOffsetY = (height - croppedDisplayHeight) / 2;
-		this.videoContainer.x = centerOffsetX;
-		this.videoContainer.y = centerOffsetY;
+		const croppedDisplayWidth = compositeLayout.screenRect.width;
+		const croppedDisplayHeight = compositeLayout.screenRect.height;
+		this.videoContainer.x = compositeLayout.screenRect.x;
+		this.videoContainer.y = compositeLayout.screenRect.y;
 
 		// scale border radius by export/preview canvas ratio
 		const previewWidth = this.config.previewWidth || 1920;
@@ -455,8 +478,9 @@ export class FrameRenderer {
 			stageSize: { width, height },
 			videoSize: { width: croppedVideoWidth, height: croppedVideoHeight },
 			baseScale: scale,
-			baseOffset: { x: centerOffsetX, y: centerOffsetY },
-			maskRect: { x: 0, y: 0, width: croppedDisplayWidth, height: croppedDisplayHeight },
+			baseOffset: { x: compositeLayout.screenRect.x, y: compositeLayout.screenRect.y },
+			maskRect: compositeLayout.screenRect,
+			webcamRect: compositeLayout.webcamRect,
 		};
 	}
 
@@ -628,34 +652,36 @@ export class FrameRenderer {
 			ctx.drawImage(videoCanvas, 0, 0, w, h);
 		}
 
-		if (webcamFrame && this.config.webcamWidth && this.config.webcamHeight) {
-			const layout = computeWebcamOverlayLayout({
-				stageWidth: w,
-				stageHeight: h,
-				videoWidth: this.config.webcamWidth,
-				videoHeight: this.config.webcamHeight,
-			});
-
-			if (layout) {
-				ctx.save();
-				ctx.beginPath();
-				ctx.roundRect(layout.x, layout.y, layout.width, layout.height, layout.borderRadius);
-				ctx.closePath();
-				ctx.shadowColor = "rgba(0,0,0,0.35)";
-				ctx.shadowBlur = 24;
-				ctx.shadowOffsetY = 10;
-				ctx.fillStyle = "#000000";
-				ctx.fill();
-				ctx.clip();
-				ctx.drawImage(
-					webcamFrame as unknown as CanvasImageSource,
-					layout.x,
-					layout.y,
-					layout.width,
-					layout.height,
-				);
-				ctx.restore();
+		const webcamRect = this.layoutCache?.webcamRect ?? null;
+		if (webcamFrame && webcamRect) {
+			const preset = getWebcamLayoutPresetDefinition(this.config.webcamLayoutPreset);
+			ctx.save();
+			ctx.beginPath();
+			ctx.roundRect(
+				webcamRect.x,
+				webcamRect.y,
+				webcamRect.width,
+				webcamRect.height,
+				webcamRect.borderRadius,
+			);
+			ctx.closePath();
+			if (preset.shadow) {
+				ctx.shadowColor = preset.shadow.color;
+				ctx.shadowBlur = preset.shadow.blur;
+				ctx.shadowOffsetX = preset.shadow.offsetX;
+				ctx.shadowOffsetY = preset.shadow.offsetY;
 			}
+			ctx.fillStyle = "#000000";
+			ctx.fill();
+			ctx.clip();
+			ctx.drawImage(
+				webcamFrame as unknown as CanvasImageSource,
+				webcamRect.x,
+				webcamRect.y,
+				webcamRect.width,
+				webcamRect.height,
+			);
+			ctx.restore();
 		}
 	}
 
@@ -673,7 +699,11 @@ export class FrameRenderer {
 		}
 		this.backgroundSprite = null;
 		if (this.app) {
-			this.app.destroy(true, { children: true, texture: true, textureSource: true });
+			this.app.destroy(true, {
+				children: true,
+				texture: true,
+				textureSource: true,
+			});
 			this.app = null;
 		}
 		this.cameraContainer = null;

src/lib/exporter/gifExporter.ts

@@ -4,6 +4,7 @@ import type {
 	CropRegion,
 	SpeedRegion,
 	TrimRegion,
+	WebcamLayoutPreset,
 	ZoomRegion,
 } from "@/components/video-editor/types";
 import { AsyncVideoFrameQueue } from "./asyncVideoFrameQueue";
@@ -39,6 +40,7 @@ interface GifExporterConfig {
 	padding?: number;
 	videoPadding?: number;
 	cropRegion: CropRegion;
+	webcamLayoutPreset?: WebcamLayoutPreset;
 	annotationRegions?: AnnotationRegion[];
 	previewWidth?: number;
 	previewHeight?: number;
@@ -136,8 +138,8 @@ export class GifExporter {
 				cropRegion: this.config.cropRegion,
 				videoWidth: videoInfo.width,
 				videoHeight: videoInfo.height,
-				webcamWidth: webcamInfo?.width,
-				webcamHeight: webcamInfo?.height,
+				webcamSize: webcamInfo ? { width: webcamInfo.width, height: webcamInfo.height } : null,
+				webcamLayoutPreset: this.config.webcamLayoutPreset,
 				annotationRegions: this.config.annotationRegions,
 				speedRegions: this.config.speedRegions,
 				previewWidth: this.config.previewWidth,

src/lib/exporter/gradientParser.test.ts

@@ -0,0 +1,58 @@
+import { describe, expect, it } from "vitest";
+import {
+	getLinearGradientPoints,
+	getRadialGradientShape,
+	parseCssGradient,
+	resolveLinearGradientAngle,
+} from "./gradientParser";
+
+describe("parseCssGradient", () => {
+	it("parses rgba-based gradient presets without splitting inside color functions", () => {
+		const parsed = parseCssGradient(
+			"linear-gradient( 111.6deg,  rgba(114,167,232,1) 9.4%, rgba(253,129,82,1) 43.9%, rgba(253,129,82,1) 54.8%, rgba(249,202,86,1) 86.3% )",
+		);
+
+		expect(parsed?.type).toBe("linear");
+		expect(parsed?.descriptor).toBe("111.6deg");
+		expect(parsed?.stops).toHaveLength(4);
+		expect(parsed?.stops.map((stop) => stop.color)).toEqual([
+			"rgba(114,167,232,1)",
+			"rgba(253,129,82,1)",
+			"rgba(253,129,82,1)",
+			"rgba(249,202,86,1)",
+		]);
+		expect(parsed?.stops[0]?.offset).toBeCloseTo(0.094);
+		expect(parsed?.stops[1]?.offset).toBeCloseTo(0.439);
+		expect(parsed?.stops[2]?.offset).toBeCloseTo(0.548);
+		expect(parsed?.stops[3]?.offset).toBeCloseTo(0.863);
+	});
+
+	it("fills missing stop positions for simple hex gradients", () => {
+		const parsed = parseCssGradient("linear-gradient(135deg, #FBC8B4, #2447B1)");
+
+		expect(parsed?.stops).toEqual([
+			{ color: "#FBC8B4", offset: 0 },
+			{ color: "#2447B1", offset: 1 },
+		]);
+	});
+});
+
+describe("gradient geometry", () => {
+	it("maps linear directions to canvas endpoints", () => {
+		const angle = resolveLinearGradientAngle("to right");
+		const points = getLinearGradientPoints(angle, 1920, 1080);
+
+		expect(points.x0).toBeCloseTo(0);
+		expect(points.y0).toBeCloseTo(540);
+		expect(points.x1).toBeCloseTo(1920);
+		expect(points.y1).toBeCloseTo(540);
+	});
+
+	it("uses radial positions from the descriptor", () => {
+		const shape = getRadialGradientShape("circle farthest-corner at 10% 20%", 1000, 500);
+
+		expect(shape.cx).toBe(100);
+		expect(shape.cy).toBe(100);
+		expect(shape.radius).toBeCloseTo(Math.hypot(900, 400));
+	});
+});

src/lib/exporter/gradientParser.ts

@@ -0,0 +1,236 @@
+export interface ParsedGradientStop {
+	color: string;
+	offset: number;
+}
+
+export interface ParsedGradient {
+	type: "linear" | "radial";
+	descriptor: string | null;
+	stops: ParsedGradientStop[];
+}
+
+const COLOR_TOKEN_RE = /^(#[0-9a-fA-F]{3,8}|(?:rgba?|hsla?)\([^)]*\)|[a-zA-Z-]+)/;
+
+export function parseCssGradient(input: string): ParsedGradient | null {
+	const gradientMatch = input.match(/^(linear|radial)-gradient\((.*)\)$/i);
+	if (!gradientMatch) {
+		return null;
+	}
+
+	const type = gradientMatch[1].toLowerCase() as ParsedGradient["type"];
+	const rawArgs = splitGradientArgs(gradientMatch[2]);
+	if (rawArgs.length === 0) {
+		return null;
+	}
+
+	let descriptor: string | null = null;
+	let stopArgs = rawArgs;
+
+	if (isGradientDescriptor(type, rawArgs[0])) {
+		descriptor = rawArgs[0];
+		stopArgs = rawArgs.slice(1);
+	}
+
+	const parsedStops = stopArgs
+		.map((part) => parseColorStop(part))
+		.filter((stop): stop is { color: string; offset: number | null } => stop !== null);
+
+	if (parsedStops.length === 0) {
+		return null;
+	}
+
+	return {
+		type,
+		descriptor,
+		stops: normalizeStopOffsets(parsedStops),
+	};
+}
+
+export function getLinearGradientPoints(angleDeg: number, width: number, height: number) {
+	const radians = (angleDeg * Math.PI) / 180;
+	const vx = Math.sin(radians);
+	const vy = -Math.cos(radians);
+	const halfSpan = (Math.abs(vx) * width + Math.abs(vy) * height) / 2;
+	const cx = width / 2;
+	const cy = height / 2;
+
+	return {
+		x0: cx - vx * halfSpan,
+		y0: cy - vy * halfSpan,
+		x1: cx + vx * halfSpan,
+		y1: cy + vy * halfSpan,
+	};
+}
+
+export function resolveLinearGradientAngle(descriptor: string | null): number {
+	if (!descriptor) {
+		return 180;
+	}
+
+	const angleMatch = descriptor.match(/(-?\d*\.?\d+)deg/i);
+	if (angleMatch) {
+		return Number.parseFloat(angleMatch[1]);
+	}
+
+	const normalized = descriptor.trim().toLowerCase().replace(/\s+/g, " ");
+	const directionMap: Record<string, number> = {
+		"to top": 0,
+		"to top right": 45,
+		"to right": 90,
+		"to bottom right": 135,
+		"to bottom": 180,
+		"to bottom left": 225,
+		"to left": 270,
+		"to top left": 315,
+	};
+
+	return directionMap[normalized] ?? 180;
+}
+
+export function getRadialGradientShape(descriptor: string | null, width: number, height: number) {
+	const atMatch = descriptor?.match(/at\s+(-?\d*\.?\d+)%\s+(-?\d*\.?\d+)%/i);
+	const cx = atMatch ? (Number.parseFloat(atMatch[1]) / 100) * width : width / 2;
+	const cy = atMatch ? (Number.parseFloat(atMatch[2]) / 100) * height : height / 2;
+
+	const distances = [
+		Math.hypot(cx, cy),
+		Math.hypot(width - cx, cy),
+		Math.hypot(cx, height - cy),
+		Math.hypot(width - cx, height - cy),
+	];
+
+	return {
+		cx,
+		cy,
+		radius: Math.max(...distances),
+	};
+}
+
+function splitGradientArgs(input: string): string[] {
+	const parts: string[] = [];
+	let current = "";
+	let depth = 0;
+
+	for (const char of input) {
+		if (char === "(") {
+			depth += 1;
+			current += char;
+			continue;
+		}
+
+		if (char === ")") {
+			depth = Math.max(0, depth - 1);
+			current += char;
+			continue;
+		}
+
+		if (char === "," && depth === 0) {
+			const trimmed = current.trim();
+			if (trimmed) {
+				parts.push(trimmed);
+			}
+			current = "";
+			continue;
+		}
+
+		current += char;
+	}
+
+	const trimmed = current.trim();
+	if (trimmed) {
+		parts.push(trimmed);
+	}
+
+	return parts;
+}
+
+function isGradientDescriptor(type: ParsedGradient["type"], part: string) {
+	if (type === "linear") {
+		return /^\s*to\s+/i.test(part) || /-?\d*\.?\d+deg/i.test(part);
+	}
+
+	return /\b(circle|ellipse|closest|farthest)\b/i.test(part) || /\bat\b/i.test(part);
+}
+
+function parseColorStop(part: string): { color: string; offset: number | null } | null {
+	const match = part.trim().match(COLOR_TOKEN_RE);
+	if (!match) {
+		return null;
+	}
+
+	const color = match[1];
+	const rest = part.slice(match[0].length);
+	const percentMatch = rest.match(/(-?\d*\.?\d+)%/);
+	const offset = percentMatch ? clamp(Number.parseFloat(percentMatch[1]) / 100, 0, 1) : null;
+
+	return { color, offset };
+}
+
+function normalizeStopOffsets(
+	stops: Array<{ color: string; offset: number | null }>,
+): ParsedGradientStop[] {
+	const explicitCount = stops.filter((stop) => stop.offset !== null).length;
+	if (explicitCount === 0) {
+		if (stops.length === 1) {
+			return [{ color: stops[0].color, offset: 0 }];
+		}
+
+		return stops.map((stop, index) => ({
+			color: stop.color,
+			offset: index / (stops.length - 1),
+		}));
+	}
+
+	const resolved = stops.map((stop) => stop.offset);
+	const firstExplicit = resolved.findIndex((offset) => offset !== null);
+	const lastExplicit = findLastDefinedIndex(resolved);
+
+	for (let index = 0; index < firstExplicit; index += 1) {
+		const end = resolved[firstExplicit] ?? 0;
+		resolved[index] = firstExplicit === 0 ? end : (end * index) / firstExplicit;
+	}
+
+	for (let index = lastExplicit + 1; index < resolved.length; index += 1) {
+		const start = resolved[lastExplicit] ?? 1;
+		const denominator = resolved.length - 1 - lastExplicit;
+		resolved[index] =
+			denominator <= 0 ? start : start + ((1 - start) * (index - lastExplicit)) / denominator;
+	}
+
+	let runStart = firstExplicit;
+	while (runStart < lastExplicit) {
+		const nextExplicit = resolved.findIndex((offset, index) => index > runStart && offset !== null);
+		if (nextExplicit === -1) {
+			break;
+		}
+
+		const start = resolved[runStart] ?? 0;
+		const end = resolved[nextExplicit] ?? start;
+		const gap = nextExplicit - runStart;
+
+		for (let index = runStart + 1; index < nextExplicit; index += 1) {
+			resolved[index] = start + ((end - start) * (index - runStart)) / gap;
+		}
+
+		runStart = nextExplicit;
+	}
+
+	return stops.map((stop, index) => ({
+		color: stop.color,
+		offset: clamp(resolved[index] ?? 0, 0, 1),
+	}));
+}
+
+function clamp(value: number, min: number, max: number) {
+	return Math.min(max, Math.max(min, value));
+}
+
+function findLastDefinedIndex(values: Array<number | null>) {
+	for (let index = values.length - 1; index >= 0; index -= 1) {
+		if (values[index] !== null) {
+			return index;
+		}
+	}
+
+	return -1;
+}

src/lib/exporter/streamingDecoder.test.ts

@@ -0,0 +1,47 @@
+import { describe, expect, it } from "vitest";
+import { shouldFailDecodeEndedEarly } from "./streamingDecoder";
+
+describe("shouldFailDecodeEndedEarly", () => {
+	it("does not fail once every segment has been satisfied", () => {
+		expect(
+			shouldFailDecodeEndedEarly({
+				cancelled: false,
+				lastDecodedFrameSec: 5.33,
+				requiredEndSec: 6.498,
+				streamDurationSec: 5.33,
+			}),
+		).toBe(false);
+	});
+
+	it("fails when decode stops far before the required end", () => {
+		expect(
+			shouldFailDecodeEndedEarly({
+				cancelled: false,
+				lastDecodedFrameSec: 5.33,
+				requiredEndSec: 10,
+				streamDurationSec: 5.33,
+			}),
+		).toBe(true);
+	});
+
+	it("fails when no frame could be decoded for a non-empty timeline", () => {
+		expect(
+			shouldFailDecodeEndedEarly({
+				cancelled: false,
+				lastDecodedFrameSec: null,
+				requiredEndSec: 1,
+			}),
+		).toBe(true);
+	});
+
+	it("fails when the decoder has not reached the reported stream end", () => {
+		expect(
+			shouldFailDecodeEndedEarly({
+				cancelled: false,
+				lastDecodedFrameSec: 4.9,
+				requiredEndSec: 6.498,
+				streamDurationSec: 5.33,
+			}),
+		).toBe(true);
+	});
+});

src/lib/exporter/streamingDecoder.ts

@@ -1,6 +1,8 @@
 import { WebDemuxer } from "web-demuxer";
 import type { SpeedRegion, TrimRegion } from "@/components/video-editor/types";
 
+const SOURCE_LOAD_TIMEOUT_MS = 60_000;
+
 export interface DecodedVideoInfo {
 	width: number;
 	height: number;
@@ -12,6 +14,55 @@ export interface DecodedVideoInfo {
 	audioCodec?: string;
 }
 
+type EarlyDecodeEndCheck = {
+	cancelled: boolean;
+	lastDecodedFrameSec: number | null;
+	requiredEndSec: number;
+	streamDurationSec?: number;
+};
+
+const EARLY_DECODE_END_THRESHOLD_SEC = 1;
+const METADATA_TAIL_TOLERANCE_SEC = 1.5;
+const STREAM_DURATION_MATCH_TOLERANCE_SEC = 0.25;
+
+export function shouldFailDecodeEndedEarly({
+	cancelled,
+	lastDecodedFrameSec,
+	requiredEndSec,
+	streamDurationSec,
+}: EarlyDecodeEndCheck): boolean {
+	if (cancelled || requiredEndSec <= 0) {
+		return false;
+	}
+
+	if (lastDecodedFrameSec === null) {
+		return true;
+	}
+
+	const decodeGapSec = requiredEndSec - lastDecodedFrameSec;
+	if (decodeGapSec <= EARLY_DECODE_END_THRESHOLD_SEC) {
+		return false;
+	}
+
+	if (typeof streamDurationSec !== "number" || !Number.isFinite(streamDurationSec)) {
+		return true;
+	}
+
+	const metadataTailSec = requiredEndSec - streamDurationSec;
+	const decodedNearStreamEnd =
+		Math.abs(lastDecodedFrameSec - streamDurationSec) <= STREAM_DURATION_MATCH_TOLERANCE_SEC;
+
+	if (
+		decodedNearStreamEnd &&
+		metadataTailSec > 0 &&
+		metadataTailSec <= METADATA_TAIL_TOLERANCE_SEC
+	) {
+		return false;
+	}
+
+	return true;
+}
+
 /** Caller must close the VideoFrame after use. */
 type OnFrameCallback = (
 	frame: VideoFrame,
@@ -36,7 +87,11 @@ export class StreamingVideoDecoder {
 		const isRemoteUrl = /^(https?:|blob:|data:)/i.test(videoUrl);
 
 		if (!isRemoteUrl && window.electronAPI?.readBinaryFile) {
-			const result = await window.electronAPI.readBinaryFile(videoUrl);
+			const result = await this.withTimeout(
+				window.electronAPI.readBinaryFile(videoUrl),
+				SOURCE_LOAD_TIMEOUT_MS,
+				"Timed out while loading the source video.",
+			);
 			if (!result.success || !result.data) {
 				throw new Error(result.message || result.error || "Failed to read source video");
 			}
@@ -49,11 +104,19 @@ export class StreamingVideoDecoder {
 			};
 		}
 
-		const response = await fetch(videoUrl);
+		const response = await this.withTimeout(
+			fetch(videoUrl),
+			SOURCE_LOAD_TIMEOUT_MS,
+			"Timed out while loading the source video.",
+		);
 		if (!response.ok) {
 			throw new Error(`Failed to fetch source video: ${response.status} ${response.statusText}`);
 		}
-		const blob = await response.blob();
+		const blob = await this.withTimeout(
+			response.blob(),
+			SOURCE_LOAD_TIMEOUT_MS,
+			"Timed out while reading the source video.",
+		);
 		const filename = videoUrl.split("/").pop() || "video";
 		return {
 			blob,
@@ -67,9 +130,17 @@ export class StreamingVideoDecoder {
 		// Relative URL so it resolves correctly in both dev (http) and packaged (file://) builds
 		const wasmUrl = new URL("./wasm/web-demuxer.wasm", window.location.href).href;
 		this.demuxer = new WebDemuxer({ wasmFilePath: wasmUrl });
-		await this.demuxer.load(file);
+		await this.withTimeout(
+			this.demuxer.load(file),
+			SOURCE_LOAD_TIMEOUT_MS,
+			"Timed out while parsing the source video.",
+		);
 
-		const mediaInfo = await this.demuxer.getMediaInfo();
+		const mediaInfo = await this.withTimeout(
+			this.demuxer.getMediaInfo(),
+			SOURCE_LOAD_TIMEOUT_MS,
+			"Timed out while reading video metadata.",
+		);
 		const videoStream = mediaInfo.streams.find((s) => s.codec_type_string === "video");
 
 		let frameRate = 60;
@@ -366,12 +437,17 @@ export class StreamingVideoDecoder {
 
 		const requiredEndSec = segments.length > 0 ? segments[segments.length - 1].endSec : 0;
 		if (
-			!this.cancelled &&
-			lastDecodedFrameSec !== null &&
-			requiredEndSec - lastDecodedFrameSec > 1
+			shouldFailDecodeEndedEarly({
+				cancelled: this.cancelled,
+				lastDecodedFrameSec,
+				requiredEndSec,
+				streamDurationSec: this.metadata.streamDuration,
+			})
 		) {
+			const decodedAtLabel =
+				lastDecodedFrameSec === null ? "no decoded frame" : `${lastDecodedFrameSec.toFixed(3)}s`;
 			throw new Error(
-				`Video decode ended early at ${lastDecodedFrameSec.toFixed(3)}s (needed ${requiredEndSec.toFixed(3)}s).`,
+				`Video decode ended early at ${decodedAtLabel} (needed ${requiredEndSec.toFixed(3)}s).`,
 			);
 		}
 	}
@@ -472,4 +548,20 @@ export class StreamingVideoDecoder {
 			this.demuxer = null;
 		}
 	}
+
+	private withTimeout<T>(promise: Promise<T>, timeoutMs: number, message: string): Promise<T> {
+		return new Promise<T>((resolve, reject) => {
+			const timer = window.setTimeout(() => reject(new Error(message)), timeoutMs);
+			promise.then(
+				(value) => {
+					window.clearTimeout(timer);
+					resolve(value);
+				},
+				(error) => {
+					window.clearTimeout(timer);
+					reject(error);
+				},
+			);
+		});
+	}
 }

src/lib/exporter/videoExporter.ts

@@ -3,6 +3,7 @@ import type {
 	CropRegion,
 	SpeedRegion,
 	TrimRegion,
+	WebcamLayoutPreset,
 	ZoomRegion,
 } from "@/components/video-editor/types";
 import { AsyncVideoFrameQueue } from "./asyncVideoFrameQueue";
@@ -12,6 +13,9 @@ import { VideoMuxer } from "./muxer";
 import { StreamingVideoDecoder } from "./streamingDecoder";
 import type { ExportConfig, ExportProgress, ExportResult } from "./types";
 
+const ENCODER_STALL_TIMEOUT_MS = 15_000;
+const ENCODER_FLUSH_TIMEOUT_MS = 20_000;
+
 interface VideoExporterConfig extends ExportConfig {
 	videoUrl: string;
 	webcamVideoUrl?: string;
@@ -27,6 +31,7 @@ interface VideoExporterConfig extends ExportConfig {
 	padding?: number;
 	videoPadding?: number;
 	cropRegion: CropRegion;
+	webcamLayoutPreset?: WebcamLayoutPreset;
 	annotationRegions?: AnnotationRegion[];
 	previewWidth?: number;
 	previewHeight?: number;
@@ -43,35 +48,76 @@ export class VideoExporter {
 	private webcamDecoder: StreamingVideoDecoder | null = null;
 	private cancelled = false;
 	private encodeQueue = 0;
-	// Increased queue size for better throughput with hardware encoding
+	// Keep a smaller queue for software encoding so Windows does not balloon memory.
 	private readonly MAX_ENCODE_QUEUE = 120;
 	private videoDescription: Uint8Array | undefined;
 	private videoColorSpace: VideoColorSpaceInit | undefined;
-	// Track muxing promises for parallel processing
 	private muxingPromises: Promise<void>[] = [];
 	private chunkCount = 0;
+	private lastEncoderOutputAt = 0;
+	private fatalEncoderError: Error | null = null;
 
 	constructor(config: VideoExporterConfig) {
 		this.config = config;
 	}
 
 	async export(): Promise<ExportResult> {
-		let webcamFrameQueue: AsyncVideoFrameQueue | null = null;
-		try {
-			this.cleanup();
-			this.cancelled = false;
+		const encoderPreferences = this.getEncoderPreferences();
+		let lastError: Error | null = null;
 
-			// Initialize streaming decoder and load video metadata
-			this.streamingDecoder = new StreamingVideoDecoder();
-			const videoInfo = await this.streamingDecoder.loadMetadata(this.config.videoUrl);
+		for (const encoderPreference of encoderPreferences) {
+			try {
+				return await this.exportWithEncoderPreference(encoderPreference);
+			} catch (error) {
+				const normalizedError = error instanceof Error ? error : new Error(String(error));
+				lastError = normalizedError;
+
+				if (this.cancelled) {
+					return { success: false, error: "Export cancelled" };
+				}
+
+				if (encoderPreferences.length > 1) {
+					console.warn(
+						`[VideoExporter] ${encoderPreference} export attempt failed:`,
+						normalizedError,
+					);
+				}
+			} finally {
+				this.cleanup();
+			}
+		}
+
+		return {
+			success: false,
+			error: lastError?.message || "Export failed",
+		};
+	}
+
+	private async exportWithEncoderPreference(
+		encoderPreference: HardwareAcceleration,
+	): Promise<ExportResult> {
+		let webcamFrameQueue: AsyncVideoFrameQueue | null = null;
+		let stopWebcamDecode = false;
+		let webcamDecodeError: Error | null = null;
+		let webcamDecodePromise: Promise<void> | null = null;
+		let webcamDecoder: StreamingVideoDecoder | null = null;
+
+		this.cleanup();
+		this.cancelled = false;
+		this.fatalEncoderError = null;
+
+		try {
+			const streamingDecoder = new StreamingVideoDecoder();
+			this.streamingDecoder = streamingDecoder;
+			const videoInfo = await streamingDecoder.loadMetadata(this.config.videoUrl);
 			let webcamInfo: Awaited<ReturnType<StreamingVideoDecoder["loadMetadata"]>> | null = null;
 			if (this.config.webcamVideoUrl) {
-				this.webcamDecoder = new StreamingVideoDecoder();
-				webcamInfo = await this.webcamDecoder.loadMetadata(this.config.webcamVideoUrl);
+				webcamDecoder = new StreamingVideoDecoder();
+				this.webcamDecoder = webcamDecoder;
+				webcamInfo = await webcamDecoder.loadMetadata(this.config.webcamVideoUrl);
 			}
 
-			// Initialize frame renderer
-			this.renderer = new FrameRenderer({
+			const renderer = new FrameRenderer({
 				width: this.config.width,
 				height: this.config.height,
 				wallpaper: this.config.wallpaper,
@@ -85,25 +131,24 @@ export class VideoExporter {
 				cropRegion: this.config.cropRegion,
 				videoWidth: videoInfo.width,
 				videoHeight: videoInfo.height,
-				webcamWidth: webcamInfo?.width,
-				webcamHeight: webcamInfo?.height,
+				webcamSize: webcamInfo ? { width: webcamInfo.width, height: webcamInfo.height } : null,
+				webcamLayoutPreset: this.config.webcamLayoutPreset,
 				annotationRegions: this.config.annotationRegions,
 				speedRegions: this.config.speedRegions,
 				previewWidth: this.config.previewWidth,
 				previewHeight: this.config.previewHeight,
 			});
-			await this.renderer.initialize();
+			this.renderer = renderer;
+			await renderer.initialize();
 
-			// Initialize video encoder
-			await this.initializeEncoder();
+			await this.initializeEncoder(encoderPreference);
 
-			// Initialize muxer (with audio if source has an audio track)
 			const hasAudio = videoInfo.hasAudio;
-			this.muxer = new VideoMuxer(this.config, hasAudio);
-			await this.muxer.initialize();
+			const muxer = new VideoMuxer(this.config, hasAudio);
+			this.muxer = muxer;
+			await muxer.initialize();
 
-			// Calculate effective duration and frame count (excluding trim regions)
-			const effectiveDuration = this.streamingDecoder.getEffectiveDuration(
+			const effectiveDuration = streamingDecoder.getEffectiveDuration(
 				this.config.trimRegions,
 				this.config.speedRegions,
 			);
@@ -115,16 +160,19 @@ export class VideoExporter {
 			console.log("[VideoExporter] Total frames to export:", totalFrames);
 			console.log("[VideoExporter] Using streaming decode (web-demuxer + VideoDecoder)");
 
-			const frameDuration = 1_000_000 / this.config.frameRate; // in microseconds
+			const frameDuration = 1_000_000 / this.config.frameRate;
 			let frameIndex = 0;
+			const maxEncodeQueue =
+				encoderPreference === "prefer-software"
+					? Math.min(this.MAX_ENCODE_QUEUE, 32)
+					: this.MAX_ENCODE_QUEUE;
+
 			webcamFrameQueue = this.config.webcamVideoUrl ? new AsyncVideoFrameQueue() : null;
-			let stopWebcamDecode = false;
-			let webcamDecodeError: Error | null = null;
-			const webcamDecodePromise =
-				this.webcamDecoder && webcamFrameQueue
+			webcamDecodePromise =
+				webcamDecoder && webcamFrameQueue
 					? (() => {
 							const queue = webcamFrameQueue;
-							return this.webcamDecoder
+							return webcamDecoder
 								.decodeAll(
 									this.config.frameRate,
 									this.config.trimRegions,
@@ -142,7 +190,7 @@ export class VideoExporter {
 								)
 								.catch((error) => {
 									webcamDecodeError = error instanceof Error ? error : new Error(String(error));
-									throw error;
+									throw webcamDecodeError;
 								})
 								.finally(() => {
 									if (webcamDecodeError) {
@@ -154,8 +202,7 @@ export class VideoExporter {
 						})()
 					: null;
 
-			// Stream decode and process frames — no seeking!
-			await this.streamingDecoder.decodeAll(
+			await streamingDecoder.decodeAll(
 				this.config.frameRate,
 				this.config.trimRegions,
 				this.config.speedRegions,
@@ -166,21 +213,22 @@ export class VideoExporter {
 							return;
 						}
 
+						if (this.fatalEncoderError) {
+							throw this.fatalEncoderError;
+						}
+
 						const timestamp = frameIndex * frameDuration;
 						webcamFrame = webcamFrameQueue ? await webcamFrameQueue.dequeue() : null;
-						const renderer = this.renderer;
-						if (this.cancelled || !renderer) {
+						if (this.cancelled) {
 							return;
 						}
 
-						// Render the frame with all effects using source timestamp
-						const sourceTimestampUs = sourceTimestampMs * 1000; // Convert to microseconds
+						const sourceTimestampUs = sourceTimestampMs * 1000;
 						await renderer.renderFrame(videoFrame, sourceTimestampUs, webcamFrame);
 
 						const canvas = renderer.getCanvas();
 
-						// Create VideoFrame from canvas on GPU without reading pixels
-						// @ts-expect-error - colorSpace not in TypeScript definitions but works at runtime
+						// @ts-expect-error - colorSpace is available at runtime even if TS does not know it.
 						const exportFrame = new VideoFrame(canvas, {
 							timestamp,
 							duration: frameDuration,
@@ -192,12 +240,19 @@ export class VideoExporter {
 							},
 						});
 
-						// Check encoder queue before encoding to keep it full
 						while (
 							this.encoder &&
-							this.encoder.encodeQueueSize >= this.MAX_ENCODE_QUEUE &&
+							this.encoder.encodeQueueSize >= maxEncodeQueue &&
 							!this.cancelled
 						) {
+							if (Date.now() - this.lastEncoderOutputAt > ENCODER_STALL_TIMEOUT_MS) {
+								exportFrame.close();
+								throw new Error(
+									encoderPreference === "prefer-hardware"
+										? "The hardware video encoder stopped responding. Retrying with a safer encoder."
+										: "The video encoder stopped responding during export.",
+								);
+							}
 							await new Promise((resolve) => setTimeout(resolve, 5));
 						}
 
@@ -211,18 +266,14 @@ export class VideoExporter {
 						}
 
 						exportFrame.close();
-
 						frameIndex++;
 
-						// Update progress
-						if (this.config.onProgress) {
-							this.config.onProgress({
-								currentFrame: frameIndex,
-								totalFrames,
-								percentage: (frameIndex / totalFrames) * 100,
-								estimatedTimeRemaining: 0,
-							});
-						}
+						this.reportProgress({
+							currentFrame: frameIndex,
+							totalFrames,
+							percentage: (frameIndex / totalFrames) * 100,
+							estimatedTimeRemaining: 0,
+						});
 					} finally {
 						videoFrame.close();
 						webcamFrame?.close();
@@ -234,38 +285,47 @@ export class VideoExporter {
 				return { success: false, error: "Export cancelled" };
 			}
 
+			if (this.fatalEncoderError) {
+				throw this.fatalEncoderError;
+			}
+
 			stopWebcamDecode = true;
 			webcamFrameQueue?.destroy();
-			this.webcamDecoder?.cancel();
+			webcamDecoder?.cancel();
 			await webcamDecodePromise;
 
-			// Finalize encoding
 			if (this.encoder && this.encoder.state === "configured") {
-				await this.encoder.flush();
+				await this.withTimeout(
+					this.encoder.flush(),
+					ENCODER_FLUSH_TIMEOUT_MS,
+					encoderPreference === "prefer-hardware"
+						? "The hardware video encoder stopped responding while finalizing the export."
+						: "The video encoder stopped responding while finalizing the export.",
+				);
+			}
+
+			if (this.fatalEncoderError) {
+				throw this.fatalEncoderError;
 			}
 
-			// Wait for all video muxing operations to complete
 			await Promise.all(this.muxingPromises);
 
-			if (this.config.onProgress) {
-				this.config.onProgress({
-					currentFrame: totalFrames,
-					totalFrames,
-					percentage: 100,
-					estimatedTimeRemaining: 0,
-					phase: "finalizing",
-				});
-			}
+			this.reportProgress({
+				currentFrame: totalFrames,
+				totalFrames,
+				percentage: 100,
+				estimatedTimeRemaining: 0,
+				phase: "finalizing",
+			});
 
-			// Process audio track if present
 			if (hasAudio && !this.cancelled) {
-				const demuxer = this.streamingDecoder!.getDemuxer();
+				const demuxer = streamingDecoder.getDemuxer();
 				if (demuxer) {
 					console.log("[VideoExporter] Processing audio track...");
 					this.audioProcessor = new AudioProcessor();
 					await this.audioProcessor.process(
 						demuxer,
-						this.muxer!,
+						muxer,
 						this.config.videoUrl,
 						this.config.trimRegions,
 						this.config.speedRegions,
@@ -274,31 +334,30 @@ export class VideoExporter {
 				}
 			}
 
-			// Finalize muxer and get output blob
-			const blob = await this.muxer!.finalize();
-
+			const blob = await muxer.finalize();
 			return { success: true, blob };
-		} catch (error) {
-			console.error("Export error:", error);
-			return {
-				success: false,
-				error: error instanceof Error ? error.message : String(error),
-			};
 		} finally {
+			stopWebcamDecode = true;
 			webcamFrameQueue?.destroy();
-			this.cleanup();
+			webcamDecoder?.cancel();
+			if (webcamDecodePromise) {
+				await webcamDecodePromise.catch(() => undefined);
+			}
 		}
 	}
 
-	private async initializeEncoder(): Promise<void> {
+	private async initializeEncoder(hardwareAcceleration: HardwareAcceleration): Promise<void> {
 		this.encodeQueue = 0;
 		this.muxingPromises = [];
 		this.chunkCount = 0;
+		this.lastEncoderOutputAt = Date.now();
+		this.fatalEncoderError = null;
 		let videoDescription: Uint8Array | undefined;
 
 		this.encoder = new VideoEncoder({
 			output: (chunk, meta) => {
-				// Capture decoder config metadata from encoder output
+				this.lastEncoderOutputAt = Date.now();
+
 				if (meta?.decoderConfig?.description && !videoDescription) {
 					const desc = meta.decoderConfig.description;
 					if (desc instanceof ArrayBuffer || desc instanceof SharedArrayBuffer) {
@@ -308,19 +367,17 @@ export class VideoExporter {
 					}
 					this.videoDescription = videoDescription;
 				}
-				// Capture colorSpace from encoder metadata if provided
+
 				if (meta?.decoderConfig?.colorSpace && !this.videoColorSpace) {
 					this.videoColorSpace = meta.decoderConfig.colorSpace;
 				}
 
-				// Stream chunk to muxer immediately (parallel processing)
 				const isFirstChunk = this.chunkCount === 0;
 				this.chunkCount++;
 
 				const muxingPromise = (async () => {
 					try {
 						if (isFirstChunk && this.videoDescription) {
-							// Add decoder config for the first chunk
 							const colorSpace = this.videoColorSpace || {
 								primaries: "bt709",
 								transfer: "iec61966-2-1",
@@ -352,43 +409,37 @@ export class VideoExporter {
 			},
 			error: (error) => {
 				console.error("[VideoExporter] Encoder error:", error);
-				// Stop export encoding failed
-				this.cancelled = true;
+				this.fatalEncoderError =
+					error instanceof Error ? error : new Error(`Video encoder error: ${String(error)}`);
+				this.streamingDecoder?.cancel();
+				this.webcamDecoder?.cancel();
 			},
 		});
 
-		const codec = this.config.codec || "avc1.640033";
-
 		const encoderConfig: VideoEncoderConfig = {
-			codec,
+			codec: this.config.codec || "avc1.640033",
 			width: this.config.width,
 			height: this.config.height,
 			bitrate: this.config.bitrate,
 			framerate: this.config.frameRate,
-			latencyMode: "quality", // Changed from 'realtime' to 'quality' for better throughput
+			latencyMode: "quality",
 			bitrateMode: "variable",
-			hardwareAcceleration: "prefer-hardware",
+			hardwareAcceleration,
 		};
 
-		// Check hardware support first
-		const hardwareSupport = await VideoEncoder.isConfigSupported(encoderConfig);
-
-		if (hardwareSupport.supported) {
-			// Use hardware encoding
-			console.log("[VideoExporter] Using hardware acceleration");
-			this.encoder.configure(encoderConfig);
-		} else {
-			// Fall back to software encoding
-			console.log("[VideoExporter] Hardware not supported, using software encoding");
-			encoderConfig.hardwareAcceleration = "prefer-software";
-
-			const softwareSupport = await VideoEncoder.isConfigSupported(encoderConfig);
-			if (!softwareSupport.supported) {
-				throw new Error("Video encoding not supported on this system");
-			}
-
-			this.encoder.configure(encoderConfig);
+		const support = await VideoEncoder.isConfigSupported(encoderConfig);
+		if (!support.supported) {
+			throw new Error(
+				hardwareAcceleration === "prefer-hardware"
+					? "Hardware video encoding is not supported on this system."
+					: "Software video encoding is not supported on this system.",
+			);
 		}
+
+		console.log(
+			`[VideoExporter] Using ${hardwareAcceleration === "prefer-hardware" ? "hardware" : "software"} acceleration`,
+		);
+		this.encoder.configure(encoderConfig);
 	}
 
 	cancel(): void {
@@ -451,5 +502,34 @@ export class VideoExporter {
 		this.chunkCount = 0;
 		this.videoDescription = undefined;
 		this.videoColorSpace = undefined;
+		this.lastEncoderOutputAt = 0;
+		this.fatalEncoderError = null;
+	}
+
+	private getEncoderPreferences(): HardwareAcceleration[] {
+		if (typeof navigator !== "undefined" && /\bWindows\b/i.test(navigator.userAgent)) {
+			return ["prefer-software", "prefer-hardware"];
+		}
+		return ["prefer-hardware", "prefer-software"];
+	}
+
+	private reportProgress(progress: ExportProgress): void {
+		this.config.onProgress?.(progress);
+	}
+
+	private withTimeout<T>(promise: Promise<T>, timeoutMs: number, message: string): Promise<T> {
+		return new Promise<T>((resolve, reject) => {
+			const timer = window.setTimeout(() => reject(new Error(message)), timeoutMs);
+			promise.then(
+				(value) => {
+					window.clearTimeout(timer);
+					resolve(value);
+				},
+				(error) => {
+					window.clearTimeout(timer);
+					reject(error);
+				},
+			);
+		});
 	}
 }

src/lib/requestCameraAccess.ts

@@ -0,0 +1,57 @@
+export type CameraAccessResult = {
+	success: boolean;
+	granted: boolean;
+	status: string;
+	error?: string;
+};
+
+function getDeniedStatus(error: unknown) {
+	if (error instanceof DOMException) {
+		return error.name;
+	}
+
+	return "unknown";
+}
+
+export async function requestCameraAccess(): Promise<CameraAccessResult> {
+	if (window.electronAPI?.requestCameraAccess) {
+		try {
+			const electronResult = await window.electronAPI.requestCameraAccess();
+			if (!electronResult.success || !electronResult.granted) {
+				return electronResult;
+			}
+		} catch (error) {
+			return {
+				success: false,
+				granted: false,
+				status: "error",
+				error: String(error),
+			};
+		}
+	}
+
+	if (!navigator.mediaDevices?.getUserMedia) {
+		return {
+			success: false,
+			granted: false,
+			status: "unsupported",
+			error: "Camera access is not supported in this runtime.",
+		};
+	}
+
+	try {
+		const stream = await navigator.mediaDevices.getUserMedia({
+			audio: false,
+			video: true,
+		});
+		stream.getTracks().forEach((track) => track.stop());
+		return { success: true, granted: true, status: "granted" };
+	} catch (error) {
+		return {
+			success: true,
+			granted: false,
+			status: getDeniedStatus(error),
+			error: String(error),
+		};
+	}
+}

src/lib/webcamOverlay.test.ts

@@ -1,33 +0,0 @@
-import { describe, expect, it } from "vitest";
-import { computeWebcamOverlayLayout } from "./webcamOverlay";
-
-describe("computeWebcamOverlayLayout", () => {
-	it("anchors the overlay in the lower-right corner", () => {
-		const layout = computeWebcamOverlayLayout({
-			stageWidth: 1920,
-			stageHeight: 1080,
-			videoWidth: 1280,
-			videoHeight: 720,
-		});
-
-		expect(layout).not.toBeNull();
-		expect(layout!.x + layout!.width).toBeLessThanOrEqual(1920);
-		expect(layout!.y + layout!.height).toBeLessThanOrEqual(1080);
-		expect(layout!.x).toBeGreaterThan(1920 / 2);
-		expect(layout!.y).toBeGreaterThan(1080 / 2);
-	});
-
-	it("keeps the overlay within the configured stage fraction while preserving aspect ratio", () => {
-		const layout = computeWebcamOverlayLayout({
-			stageWidth: 1280,
-			stageHeight: 720,
-			videoWidth: 1920,
-			videoHeight: 1080,
-		});
-
-		expect(layout).not.toBeNull();
-		expect(layout!.width).toBeLessThanOrEqual(Math.round(1280 * 0.18) + 1);
-		expect(layout!.height).toBeLessThanOrEqual(Math.round(720 * 0.18) + 1);
-		expect(Math.abs(layout!.width * 1080 - layout!.height * 1920)).toBeLessThanOrEqual(1920);
-	});
-});

src/lib/webcamOverlay.ts

@@ -1,45 +0,0 @@
-export interface WebcamOverlayLayout {
-	x: number;
-	y: number;
-	width: number;
-	height: number;
-	margin: number;
-	borderRadius: number;
-}
-
-const MAX_STAGE_FRACTION = 0.18;
-const MARGIN_FRACTION = 0.02;
-const MIN_SIZE = 96;
-const MAX_BORDER_RADIUS = 24;
-
-export function computeWebcamOverlayLayout(params: {
-	stageWidth: number;
-	stageHeight: number;
-	videoWidth: number;
-	videoHeight: number;
-}): WebcamOverlayLayout | null {
-	const { stageWidth, stageHeight, videoWidth, videoHeight } = params;
-
-	if (stageWidth <= 0 || stageHeight <= 0 || videoWidth <= 0 || videoHeight <= 0) {
-		return null;
-	}
-
-	const margin = Math.max(12, Math.round(Math.min(stageWidth, stageHeight) * MARGIN_FRACTION));
-	const maxWidth = Math.max(MIN_SIZE, stageWidth * MAX_STAGE_FRACTION);
-	const maxHeight = Math.max(MIN_SIZE, stageHeight * MAX_STAGE_FRACTION);
-	const scale = Math.min(maxWidth / videoWidth, maxHeight / videoHeight);
-	const width = Math.round(videoWidth * scale);
-	const height = Math.round(videoHeight * scale);
-
-	return {
-		x: Math.max(0, Math.round(stageWidth - margin - width)),
-		y: Math.max(0, Math.round(stageHeight - margin - height)),
-		width,
-		height,
-		margin,
-		borderRadius: Math.min(
-			MAX_BORDER_RADIUS,
-			Math.max(12, Math.round(Math.min(width, height) * 0.12)),
-		),
-	};
-}

tests/e2e/gif-export.spec.ts

@@ -87,8 +87,8 @@ test("exports a GIF from a loaded video", async () => {
 		await editorWindow.getByTestId("testId-gif-format-button").click();
 		await editorWindow.getByTestId("testId-export-button").click();
 
-		// ── 6. Wait for the toast to say exported successfully
-		await expect(editorWindow.getByText(`GIF exported successfully to pending`)).toBeVisible({
+		// ── 6. Wait for the success toast.
+		await expect(editorWindow.getByText("GIF exported successfully")).toBeVisible({
 			timeout: 90_000,
 		});