Flip Camera

src/index.html

@@ -212,6 +212,15 @@ <h2 class="text-xs font-medium text-neutral-500 uppercase tracking-wider mb-2">R
               id="cameraSource"
               class="w-full bg-neutral-900 border border-neutral-800 rounded-lg px-2.5 py-1.5 text-sm focus:outline-none focus:ring-1 focus:ring-neutral-600 transition-colors"
             ></select>
+            <label class="mt-1.5 flex items-center gap-2 text-xs text-neutral-400 cursor-pointer">
+              <input
+                type="checkbox"
+                id="cameraMirrorCheckbox"
+                class="accent-neutral-400"
+                checked
+              />
+              <span>Mirror camera</span>
+            </label>
           </div>
           <div>
             <label class="block text-xs font-medium text-neutral-500 uppercase tracking-wider mb-1"

src/main/services/premiere-export-service.ts

@@ -48,6 +48,9 @@ export interface PremiereExportOptions {
   sourceWidth: number;
   sourceHeight: number;
   cameraSyncOffsetMs: number;
+  // Defaults to true to preserve historical selfie-mirror behavior when the
+  // caller has not yet plumbed the setting through.
+  cameraMirror?: boolean;
   takes: PremiereExportTakeInput[];
   sections: PremiereExportSectionInput[];
   keyframes: Keyframe[];
@@ -139,10 +142,13 @@ function buildCameraTranscodeArgs(
   inputPath: string,
   outputPath: string,
   cameraSyncOffsetMs: number,
-  includeAudio: boolean
+  includeAudio: boolean,
+  mirror: boolean
 ): string[] {
-  // Mirror horizontally only; preserve native dimensions so the user can
-  // expand / re-crop the full camera frame in Premiere.
+  // Preserve native dimensions so the user can expand / re-crop the full
+  // camera frame in Premiere. Horizontal mirroring is optional so projects
+  // that disable selfie-mirror do not get a flipped asset shipped to the
+  // NLE.
   const offsetSec = normalizeCameraSyncOffsetMs(cameraSyncOffsetMs) / 1000;
   const args = [
     '-progress',
@@ -154,7 +160,8 @@ function buildCameraTranscodeArgs(
   if (Math.abs(offsetSec) > 0.0005) {
     args.push('-itsoffset', (-offsetSec).toFixed(3));
   }
-  args.push('-i', inputPath, '-map', '0:v:0?', '-vf', 'hflip,setsar=1');
+  const videoFilter = mirror ? 'hflip,setsar=1' : 'setsar=1';
+  args.push('-i', inputPath, '-map', '0:v:0?', '-vf', videoFilter);
   if (includeAudio) {
     // Camera file owns the mic for this take; preserve it so Premiere can
     // import the PiP clip with its built-in audio track.
@@ -351,7 +358,8 @@ export async function exportPremiereProject(
         job.inputPath,
         job.outputPath,
         opts.cameraSyncOffsetMs,
-        job.includeCameraAudio === true
+        job.includeCameraAudio === true,
+        opts.cameraMirror !== false
       );
     } else {
       args = buildAudioTranscodeArgs(job.inputPath, job.outputPath);

src/main/services/preview-render-service.ts

@@ -62,6 +62,7 @@ export interface ComputeTimelineHashInput {
   cameraSyncOffsetMs: number;
   sourceWidth: number;
   sourceHeight: number;
+  cameraMirror?: boolean;
 }
 
 function round(value: unknown, digits = 3): number {
@@ -130,7 +131,11 @@ export function computeTimelineHash(input: ComputeTimelineHashInput): string {
     fit: input?.screenFitMode === 'fit' ? 'fit' : 'fill',
     camSync: Math.round(Number(input?.cameraSyncOffsetMs) || 0),
     w: Math.round(Number(input?.sourceWidth) || 0),
-    h: Math.round(Number(input?.sourceHeight) || 0)
+    h: Math.round(Number(input?.sourceHeight) || 0),
+    // Including the mirror flag in the hash ensures that toggling the
+    // camera orientation invalidates any cached preview so the next render
+    // actually reflects the new setting.
+    camMirror: input?.cameraMirror !== false
   };
 
   return crypto.createHash('sha256').update(JSON.stringify(payload)).digest('hex').slice(0, 16);
@@ -159,6 +164,7 @@ export interface GeneratePreviewOpts {
   cameraSyncOffsetMs: number;
   sourceWidth: number;
   sourceHeight: number;
+  cameraMirror?: boolean;
 }
 
 export interface GeneratePreviewResult {
@@ -213,6 +219,7 @@ export async function generatePreview(
       exportAudioPreset,
       exportVideoPreset,
       cameraSyncOffsetMs: opts.cameraSyncOffsetMs,
+      cameraMirror: opts.cameraMirror,
       sourceWidth: opts.sourceWidth,
       sourceHeight: opts.sourceHeight,
       outputPath: previewPath

src/main/services/render-filter-service.ts

@@ -248,7 +248,8 @@ export function buildFilterComplex(
   sourceHeight: number,
   canvasW: number,
   canvasH: number,
-  targetFps = 30
+  targetFps = 30,
+  cameraMirror = true
 ): string {
   const { outW, outH } = resolveOutputSize(canvasW, canvasH);
   const scaleX = outW / AUTHORING_CANVAS_W;
@@ -282,6 +283,11 @@ export function buildFilterComplex(
   const hasPip = keyframes.some((keyframe) => keyframe.pipVisible);
   const hasCamFull = keyframes.some((keyframe) => keyframe.cameraFullscreen);
 
+  // Only emit hflip when the project wants the camera mirrored. Dropping the
+  // filter entirely (vs. letting it be a no-op) keeps the filter graph a hair
+  // simpler and makes the intent clear when inspecting the ffmpeg command.
+  const mirrorChain = cameraMirror ? ',hflip' : '';
+
   if (hasPip && hasCamFull) {
     const alphaExpr = buildAlphaExpr(keyframes);
     const roundCornerExpr = `lte(pow(max(0,max(${radius}-X,X-${maxCoord})),2)+pow(max(0,max(${radius}-Y,Y-${maxCoord})),2),${radiusSquared})`;
@@ -293,18 +299,18 @@ export function buildFilterComplex(
     const xExpr = buildPosExpr(scaledKeyframes, 'pipX');
     const yExpr = buildPosExpr(scaledKeyframes, 'pipY');
 
-    return `${screenFilter};[1:v]setpts=PTS-STARTPTS,hflip,split[cam1][cam2];${camPipFilter};${camFullFilter};[screen][cam]overlay=x='${xExpr}':y='${yExpr}':format=auto[with_pip];[with_pip][camfull]overlay=0:0:format=auto[out]`;
+    return `${screenFilter};[1:v]setpts=PTS-STARTPTS${mirrorChain},split[cam1][cam2];${camPipFilter};${camFullFilter};[screen][cam]overlay=x='${xExpr}':y='${yExpr}':format=auto[with_pip];[with_pip][camfull]overlay=0:0:format=auto[out]`;
   }
 
   if (hasCamFull) {
     const camFullAlpha = buildCamFullAlphaExpr(keyframes);
-    const camFullFilter = `[1:v]setpts=PTS-STARTPTS,hflip,scale=${outW}:${outH}:flags=lanczos:force_original_aspect_ratio=increase,crop=${outW}:${outH},format=yuva420p,geq=lum='lum(X,Y)':cb='cb(X,Y)':cr='cr(X,Y)':a='255*(${camFullAlpha})'[camfull]`;
+    const camFullFilter = `[1:v]setpts=PTS-STARTPTS${mirrorChain},scale=${outW}:${outH}:flags=lanczos:force_original_aspect_ratio=increase,crop=${outW}:${outH},format=yuva420p,geq=lum='lum(X,Y)':cb='cb(X,Y)':cr='cr(X,Y)':a='255*(${camFullAlpha})'[camfull]`;
     return `${screenFilter};${camFullFilter};[screen][camfull]overlay=0:0:format=auto[out]`;
   }
 
   const alphaExpr = buildAlphaExpr(keyframes);
   const roundCornerExpr = `lte(pow(max(0,max(${radius}-X,X-${maxCoord})),2)+pow(max(0,max(${radius}-Y,Y-${maxCoord})),2),${radiusSquared})`;
-  const camFilter = `[1:v]setpts=PTS-STARTPTS,hflip,crop='min(iw,ih)':'min(iw,ih)':'(iw-min(iw,ih))/2':'(ih-min(iw,ih))/2',scale=${actualPipSize}:${actualPipSize},format=yuva420p,geq=lum='lum(X,Y)':cb='cb(X,Y)':cr='cr(X,Y)':a='255*${roundCornerExpr}*(${alphaExpr})'[cam]`;
+  const camFilter = `[1:v]setpts=PTS-STARTPTS${mirrorChain},crop='min(iw,ih)':'min(iw,ih)':'(iw-min(iw,ih))/2':'(ih-min(iw,ih))/2',scale=${actualPipSize}:${actualPipSize},format=yuva420p,geq=lum='lum(X,Y)':cb='cb(X,Y)':cr='cr(X,Y)':a='255*${roundCornerExpr}*(${alphaExpr})'[cam]`;
 
   const xExpr = buildPosExpr(scaledKeyframes, 'pipX');
   const yExpr = buildPosExpr(scaledKeyframes, 'pipY');

src/main/services/render-service.ts

@@ -59,6 +59,10 @@ export interface RenderCompositeOptions {
   exportAudioPreset?: ExportAudioPreset;
   exportVideoPreset?: ExportVideoPreset;
   cameraSyncOffsetMs?: number;
+  // Whether the camera should be mirrored horizontally in the composite.
+  // Defaults to true to preserve historical behavior for legacy callers that
+  // do not plumb this option through.
+  cameraMirror?: boolean;
   sourceWidth?: number;
   sourceHeight?: number;
   outputFolder?: string;
@@ -574,6 +578,7 @@ export async function renderComposite(
   const keyframes = Array.isArray(opts.keyframes) ? opts.keyframes : [];
   const pipSize = Number.isFinite(Number(opts.pipSize)) ? Number(opts.pipSize) : 422;
   const screenFitMode = opts.screenFitMode === 'fit' ? 'fit' : 'fill';
+  const cameraMirror = opts.cameraMirror !== false;
   const exportAudioPreset = normalizeExportAudioPreset(opts.exportAudioPreset);
   const exportVideoPreset = normalizeExportVideoPreset(opts.exportVideoPreset);
   const cameraSyncOffsetMs = normalizeCameraSyncOffsetMs(opts.cameraSyncOffsetMs);
@@ -813,7 +818,8 @@ export async function renderComposite(
       sourceHeight,
       canvasW,
       canvasH,
-      targetFps
+      targetFps,
+      cameraMirror
     );
     assertOverlayFilterSize(overlayFilter);
     const adaptedOverlay = overlayFilter