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@acro5piano
Last active June 26, 2021 07:34
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Background blur-ed Twilio video track
export const MyComponent() {
const { toggleVideoBlur, isVideoBlur } = useBlurLocalTrack({})
const _toggleVideoBlur = async () => {
twilioRoom.localParticipant.videoTracks.forEach((track) => track.unpublish())
const videoTrack = await toggleVideoBlur()
await wait(1000)
participant.publishTrack(videoTrack)
}
return <button onclick={_toggleVideoBlur}>{isVideoBlur ? 'Disable Blur' : 'Enable blur'}</button>
}
<!-- [Tensorflow (for video blur)] -->
<!-- CDN Install is the easiest way (Webpack + npm creates error) -->
<script src="https://cdn.jsdelivr.net/npm/@tensorflow/[email protected]"></script>
<script src="https://cdn.jsdelivr.net/npm/@tensorflow-models/[email protected]"></script>
<canvas id="canvas" class="renderer" width="640" height="480"></canvas>
<video id="video" class="renderer" width="640" height="480"></video>
<!-- [/Tensorflow] -->
</body>
</html>
import { useCallback, useState } from 'react'
import { wait } from 'src/utilities/wait'
import { LocalVideoTrack } from 'twilio-video'
declare global {
export interface HTMLCanvasElement {
captureStream(frameRate: number): MediaStream
}
var bodyPix: typeof import('@tensorflow-models/body-pix')
}
interface UseBlurLocalTrackArgs {
onCreateVideoTrack?: (track: LocalVideoTrack) => void
}
// TODO: Someday we'll create an OSS for this
export const useBlurLocalTrack = ({
onCreateVideoTrack,
}: UseBlurLocalTrackArgs) => {
const [isVideoBlur, setIsVideoBlur] = useState(false)
const toggleVideoBlur = useCallback(async () => {
setIsVideoBlur(!isVideoBlur)
const canvas = document.getElementById('canvas') as HTMLCanvasElement
const video = document.getElementById('video') as HTMLVideoElement
const stream = await navigator.mediaDevices.getUserMedia({
video: true,
audio: false,
})
if (isVideoBlur) {
video.pause()
video.srcObject = null
const videoTrack = new LocalVideoTrack(stream.getVideoTracks()[0])
onCreateVideoTrack && onCreateVideoTrack(videoTrack)
return videoTrack
}
const net = await bodyPix.load({
multiplier: 0.75,
quantBytes: 2,
architecture: 'MobileNetV1',
outputStride: 16,
})
video.addEventListener('play', () => {
async function step() {
const segmentation = await net.segmentPerson(video)
await bodyPix.drawBokehEffect(
canvas,
video,
segmentation,
6, // backgroundBlurAmount
2, // edgeBlurAmount
false, // flipHorizontal
)
// Add delay to decrease frame rate for performance reason
setTimeout(() => {
requestAnimationFrame(step)
}, 80) // TODO: make this value configurable based on user device
}
requestAnimationFrame(step)
})
video.srcObject = stream
// Add delay to wait for video strem is ready
await wait(1000)
await video.play()
// This delay is important for Firefox!
await wait(1000)
const localVideoTrack = new LocalVideoTrack(
canvas.captureStream(10).getVideoTracks()[0]
)
onCreateVideoTrack && onCreateVideoTrack(localVideoTrack)
return localVideoTrack
}, [isVideoBlur, onCreateVideoTrack])
return { toggleVideoBlur, isVideoBlur }
}
@chand1012
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Can you show an example of this being used in twilio-video-app-react?

@acro5piano
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Author

acro5piano commented Jun 26, 2021

@chand1012

It should require a hard work and I'm not interested in it. Please fit this example into your project.
Basically this code does

  • Capture video from webcam using getUserMedia
  • Render the video
  • Render the video to canvas from the video tag
  • Blur background of canvas data
  • Create a new video track from the canvas

So the data flow is like this:

WebCam -> VideoStream -> video -> canvas -> VideoStream -> VideoTrack

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