fix(virtual-background): Fix mirror behavior for remote participants.

react/features/stream-effects/virtual-background/JitsiStreamBackgroundEffect.js

 
         const track = this._stream.getVideoTracks()[0];
         const { height, width } = track.getSettings() ?? track.getConstraints();
+        const { backgroundType } = this._options.virtualBackground;
 
         this._outputCanvasElement.height = height;
         this._outputCanvasElement.width = width;
         this._outputCanvasCtx.globalCompositeOperation = 'copy';
 
         // Draw segmentation mask.
-        //
 
         // Smooth out the edges.
-        if (this._options.virtualBackground.backgroundType === VIRTUAL_BACKGROUND_TYPE.IMAGE) {
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.IMAGE) {
             this._outputCanvasCtx.filter = 'blur(4px)';
         } else {
             this._outputCanvasCtx.filter = 'blur(8px)';
         }
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
+            // Save current context before applying transformations.
+            this._outputCanvasCtx.save();
 
+            // Flip the canvas and prevent mirror behaviour.
+            this._outputCanvasCtx.scale(-1, 1);
+            this._outputCanvasCtx.translate(-this._outputCanvasElement.width, 0);
+        }
         this._outputCanvasCtx.drawImage(
             this._segmentationMaskCanvas,
             0,
             this._inputVideoElement.width,
             this._inputVideoElement.height
         );
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
+            this._outputCanvasCtx.restore();
+        }
         this._outputCanvasCtx.globalCompositeOperation = 'source-in';
         this._outputCanvasCtx.filter = 'none';
 
         // Draw the foreground video.
-        //
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
+            // Save current context before applying transformations.
+            this._outputCanvasCtx.save();
 
+            // Flip the canvas and prevent mirror behaviour.
+            this._outputCanvasCtx.scale(-1, 1);
+            this._outputCanvasCtx.translate(-this._outputCanvasElement.width, 0);
+        }
         this._outputCanvasCtx.drawImage(this._inputVideoElement, 0, 0);
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
+            this._outputCanvasCtx.restore();
+        }
 
         // Draw the background.
-        //
 
         this._outputCanvasCtx.globalCompositeOperation = 'destination-over';
-        if (this._options.virtualBackground.backgroundType === VIRTUAL_BACKGROUND_TYPE.IMAGE) {
+        if (backgroundType === VIRTUAL_BACKGROUND_TYPE.IMAGE
+            || backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
             this._outputCanvasCtx.drawImage(
-                this._virtualImage,
-                0,
-                0,
-                this._inputVideoElement.width,
-                this._inputVideoElement.height
-            );
-        }
-        if (this._options.virtualBackground.backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
-
-            // save current context before applying transformations
-            this._outputCanvasCtx.save();
-
-            // flip the canvas and prevent mirror behaviour
-            this._outputCanvasCtx.scale(-1, 1);
-            this._outputCanvasCtx.translate(-this._outputCanvasElement.width, 0);
-            this._outputCanvasCtx.drawImage(
-                this._virtualVideo,
+                backgroundType === VIRTUAL_BACKGROUND_TYPE.IMAGE
+                    ? this._virtualImage : this._virtualVideo,
                 0,
                 0,
                 this._outputCanvasElement.width,
                 this._outputCanvasElement.height
             );
-
-            // restore the canvas
-            this._outputCanvasCtx.restore();
         } else {
             this._outputCanvasCtx.filter = `blur(${this._options.virtualBackground.blurValue}px)`;
             this._outputCanvasCtx.drawImage(this._inputVideoElement, 0, 0);

react/features/virtual-background/components/VirtualBackgroundDialog.js

         if (storedImages.length === backgroundsLimit) {
             setStoredImages(storedImages.slice(1));
         }
-        if (!_localFlipX) {
-            dispatch(updateSettings({
-                localFlipX: !_localFlipX
-            }));
-        }
-    }, [ storedImages, _localFlipX ]);
+    }, [ storedImages ]);
 
 
     const enableBlur = useCallback(async () => {
         setLoading(true);
         await dispatch(toggleBackgroundEffect(options, _jitsiTrack));
         await setLoading(false);
+        if (_localFlipX && options.backgroundType === VIRTUAL_BACKGROUND_TYPE.DESKTOP_SHARE) {
+            dispatch(updateSettings({
+                localFlipX: !_localFlipX
+            }));
+        }
         dispatch(hideDialog());
-    }, [ dispatch, options ]);
+    }, [ dispatch, options, _localFlipX ]);
 
     // Prevent the selection of a new virtual background if it has not been applied by default
     const cancelVirtualBackground = useCallback(async () => {

react/features/virtual-background/components/VirtualBackgroundPreview.js

 import { VIRTUAL_BACKGROUND_TYPE } from '../constants';
 import { localTrackStopped } from '../functions';
 
-const videoClassName = 'video-preview-video flipVideoX';
+const videoClassName = 'video-preview-video';
 
 /**
  * The type of the React {@code PureComponent} props of {@link VirtualBackgroundPreview}.