✨(frontend) introduce blurring effects for Chromium-based users

Implemented using MediaPipe, which is not supported on Firefox due to
limitations outlined in issue #38 of the track-processors-js repo.

We decided to release this first version exclusively for Chrome to quickly
offer a solution to users. Future iterations will address broader compatibility.

An informational message will be added to notify users that the feature is
experimental. For now, a text label will be used in place of an icon.

src/frontend/src/features/rooms/livekit/components/Effects.tsx

@@ -1,24 +1,72 @@
-import { useEffect, useRef } from 'react'
+import { useEffect, useRef, useState } from 'react'
 import { useLocalParticipant } from '@livekit/components-react'
 import { LocalVideoTrack } from 'livekit-client'
-import { Div, P } from '@/primitives'
+import { Text, P, ToggleButton } from '@/primitives'
 import { useTranslation } from 'react-i18next'
+import { HStack, VStack } from '@/styled-system/jsx'
+import {
+  BackgroundBlur,
+  BackgroundOptions,
+  ProcessorWrapper,
+  BackgroundTransformer,
+} from '@livekit/track-processors'
+
+enum BlurRadius {
+  NONE = 0,
+  LIGHT = 5,
+  NORMAL = 10,
+}
 
 export const Effects = () => {
   const { t } = useTranslation('rooms', { keyPrefix: 'effects' })
-  const { isCameraEnabled, cameraTrack } = useLocalParticipant()
+  const { isCameraEnabled, cameraTrack, localParticipant } =
+    useLocalParticipant()
   const videoRef = useRef<HTMLVideoElement>(null)
+  const [processorPending, setProcessorPending] = useState(false)
 
   const localCameraTrack = cameraTrack?.track as LocalVideoTrack
 
+  const getProcessor = () => {
+    return localCameraTrack?.getProcessor() as ProcessorWrapper<BackgroundOptions>
+  }
+
+  const getBlurRadius = (): BlurRadius => {
+    const processor = getProcessor()
+    return (
+      (processor?.transformer as BackgroundTransformer)?.options?.blurRadius ||
+      BlurRadius.NONE
+    )
+  }
+
+  const toggleBlur = async (blurRadius: number) => {
+    if (!isCameraEnabled) await localParticipant.setCameraEnabled(true)
+    if (!localCameraTrack) return
+
+    setProcessorPending(true)
+
+    const processor = getProcessor()
+    const currentBlurRadius = getBlurRadius()
+
+    try {
+      if (blurRadius == currentBlurRadius && processor) {
+        await localCameraTrack.stopProcessor()
+      } else if (!processor) {
+        await localCameraTrack.setProcessor(BackgroundBlur(blurRadius))
+      } else {
+        await processor?.updateTransformerOptions({ blurRadius })
+      }
+    } catch (error) {
+      console.error('Error applying blur:', error)
+    } finally {
+      setProcessorPending(false)
+    }
+  }
+
   useEffect(() => {
     const videoElement = videoRef.current
+    if (!videoElement) return
 
-    const attachVideoTrack = async () => {
+    const attachVideoTrack = async () => localCameraTrack?.attach(videoElement)
-      if (!videoElement) return
-      localCameraTrack?.attach(videoElement)
-    }
-
     attachVideoTrack()
 
     return () => {
@@ -27,8 +75,16 @@ export const Effects = () => {
     }
   }, [localCameraTrack, isCameraEnabled])
 
+  const isSelected = (blurRadius: BlurRadius) => {
+    return isCameraEnabled && getBlurRadius() == blurRadius
+  }
+
+  const tooltipLabel = (blurRadius: BlurRadius) => {
+    return t(`blur.${isSelected(blurRadius) ? 'clear' : 'apply'}`)
+  }
+
   return (
-    <Div padding="0 1.5rem">
+    <VStack padding="0 1.5rem">
       {localCameraTrack && isCameraEnabled ? (
         <video
           ref={videoRef}
@@ -63,6 +119,34 @@ export const Effects = () => {
           </P>
         </div>
       )}
-    </Div>
+      {ProcessorWrapper.isSupported ? (
+        <HStack>
+          <ToggleButton
+            size={'sm'}
+            legacyStyle
+            aria-label={tooltipLabel(BlurRadius.LIGHT)}
+            tooltip={tooltipLabel(BlurRadius.LIGHT)}
+            isDisabled={processorPending}
+            onPress={async () => await toggleBlur(BlurRadius.LIGHT)}
+            isSelected={isSelected(BlurRadius.LIGHT)}
+          >
+            {t('blur.light')}
+          </ToggleButton>
+          <ToggleButton
+            size={'sm'}
+            legacyStyle
+            aria-label={tooltipLabel(BlurRadius.NORMAL)}
+            tooltip={tooltipLabel(BlurRadius.NORMAL)}
+            isDisabled={processorPending}
+            onPress={async () => await toggleBlur(BlurRadius.NORMAL)}
+            isSelected={isSelected(BlurRadius.NORMAL)}
+          >
+            {t('blur.normal')}
+          </ToggleButton>
+        </HStack>
+      ) : (
+        <Text variant="sm">{t('notAvailable')}</Text>
+      )}
+    </VStack>
   )
 }

src/frontend/src/locales/de/rooms.json

@@ -74,7 +74,14 @@
     }
   },
   "effects": {
-    "activateCamera": ""
+    "activateCamera": "",
+    "notAvailable": "",
+    "blur": {
+      "light": "",
+      "normal": "",
+      "apply": "",
+      "clear": ""
+    }
   },
   "sidePanel": {
     "heading": {

src/frontend/src/locales/en/rooms.json

@@ -72,7 +72,14 @@
     }
   },
   "effects": {
-    "activateCamera": "Camera is disabled"
+    "activateCamera": "Your camera is disabled. Choose an option to enable it.",
+    "notAvailable": "The blur effect will be available soon on your browser. We're working on it! In the meantime, you can use Google Chrome :(",
+    "blur": {
+      "light": "Light blur",
+      "normal": "Blur",
+      "apply": "Enable blur",
+      "clear": "Disable blur"
+    }
   },
   "sidePanel": {
     "heading": {

src/frontend/src/locales/fr/rooms.json

@@ -72,7 +72,14 @@
     }
   },
   "effects": {
-    "activateCamera": "Votre camera est désactivée"
+    "activateCamera": "Votre camera est désactivée. Choisissez une option pour l'activer.",
+    "notAvailable": "L'effet de flou sera bientôt disponible sur votre navigateur. Nous y travaillons ! En attendant, vous pouvez utiliser Google Chrome :(",
+    "blur": {
+      "light": "Léger flou",
+      "normal": "Flou",
+      "apply": "Appliquer le flou",
+      "clear": "Désactiver le flou"
+    }
   },
   "sidePanel": {
     "heading": {