Differential D2978 Diff 8513 src/resources/js/meet/media.js

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src/resources/js/meet/media.js

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				'use strict'

				function Media()
				{
				let audioActive = null // True if the audio track is active
				let videoActive = null // True if the video track is active
				let audioSource = '' // Current audio device identifier
				let videoSource = '' // Current video device identifier
				let cameras = [] // List of user video devices
				let microphones = [] // List of user audio devices
				let setupVideoElement // <video> element for setup process
				let setupVolumeElement // Volume indicator element for setup process


				this.getAudioDevices = async () => {
				let audioDevices = {}

				try
				{
				const devices = await navigator.mediaDevices.enumerateDevices()

				for (const device of devices) {
				if (device.kind !== 'audioinput') {
				continue
				}

				audioDevices[device.deviceId] = device
				}
				}
				catch (error) {
				console.error(error)
				}

				return audioDevices
				}

				this.getWebcams = async () => {
				let webcamDevices = {}

				try {
				const devices = await navigator.mediaDevices.enumerateDevices()

				for (const device of devices) {
				if (device.kind !== 'videoinput') {
				continue
				}

				webcamDevices[device.deviceId] = device
				}
				}
				catch (error) {
				console.error(error)
				}

				return webcamDevices
				}

				this.getMediaStream = async (successCallback, errorCallback) => {
				const constraints = { audio: true, video: true }

				if (videoSource)
				constraints.video = { deviceId: videoSource }
				if (audioSource)
				constraints.audio = { deviceId: audioSource }

				navigator.mediaDevices.getUserMedia(constraints)
				.then(mediaStream => {
				successCallback(mediaStream)
				})
				.catch(error => {
				errorCallback(error)
				})
				}

				this.getTrack = async (constraints) => {
				const stream = await navigator.mediaDevices.getUserMedia(constraints)

				if (constraints.audio) {
				return stream.getAudioTracks()[0]
				}

				return stream.getVideoTracks()[0]
				}

				this.getDisplayTrack = async (constraints) => {
				const stream = await navigator.mediaDevices.getDisplayMedia(constraints)

				if (constraints.audio) {
				return stream.getAudioTracks()[0]
				}

				return stream.getVideoTracks()[0]
				}

				this.createVideoElement = (tracks, props) => {
				const videoElement = document.createElement('video')

				const stream = new MediaStream()

				tracks.forEach(track => stream.addTrack(track))

				videoElement.srcObject = stream

				this.setVideoProps(videoElement, props)

				return videoElement
				}

				/**
				* Make a picture from a video element
				*/
				this.makePicture = (videoElement) => {
				// Skip if video is not "playing"
				if (!videoElement.videoWidth) {
				return
				}

				// we're going to crop a square from the video and resize it
				const maxSize = 64

				// Calculate sizing
				let sh = Math.floor(videoElement.videoHeight / 1.5)
				let sw = sh
				let sx = (videoElement.videoWidth - sw) / 2
				let sy = (videoElement.videoHeight - sh) / 2

				let dh = Math.min(sh, maxSize)
				let dw = sh < maxSize ? sw : Math.floor(sw * dh/sh)

				const canvas = $("<canvas>")[0]
				canvas.width = dw
				canvas.height = dh

				// draw the image on the canvas (square cropped and resized)
				canvas.getContext('2d').drawImage(videoElement, sx, sy, sw, sh, 0, 0, dw, dh)

				// convert it to a usable data URL (png format)
				return canvas.toDataURL()
				}

				/**
				* Set video element properties
				*/
				this.setVideoProps = (videoElement, props) => {
				videoElement.autoplay = true
				videoElement.controls = false
				videoElement.muted = props.muted \|\| false
				videoElement.disablePictureInPicture = true // this does not work in Firefox
				videoElement.tabIndex = -1
				videoElement.setAttribute('playsinline', 'true')

				if (props.mirror) {
				videoElement.style.transform = 'rotateY(180deg)'
				videoElement.style.webkitTransform = 'rotateY(180deg)'
				}
				}

				/**
				* Sets the audio and video devices for the session.
				* This will ask user for permission to access media devices.
				*
				* @param props Setup properties (videoElement, volumeElement, onSuccess, onError)
				*/
				this.setupStart = (props) => {
				setupVideoElement = props.videoElement
				setupVolumeElement = props.volumeElement

				const callback = async (mediaStream) => {
				if (audioActive === false) {
				this.removeTracksFromStream(mediaStream, 'Audio')
				}
				if (videoActive === false) {
				this.removeTracksFromStream(mediaStream, 'Video')
				}

				let videoStream = mediaStream.getVideoTracks()[0]
				let audioStream = mediaStream.getAudioTracks()[0]

				audioActive = !!audioStream
				videoActive = !!videoStream

				this.setVideoProps(setupVideoElement, { mirror: true, muted: true })
				setupVideoElement.srcObject = mediaStream

				if (audioActive) {
				volumeMeterStart()
				}

				microphones = await this.getAudioDevices()
				cameras = await this.getWebcams()

				Object.keys(cameras).forEach(deviceId => {
				// device's props: deviceId, kind, label
				const device = cameras[deviceId]
				if (videoStream && videoStream.label == device.label) {
				videoSource = device.deviceId
				}
				})

				Object.keys(microphones).forEach(deviceId => {
				const device = microphones[deviceId]
				if (audioStream && audioStream.label == device.label) {
				audioSource = device.deviceId
				}
				})

				props.onSuccess({
				microphones,
				cameras,
				audioSource,
				videoSource,
				audioActive,
				videoActive
				})
				}

				this.getMediaStream(callback, props.onError)
				}

				/**
				* Stop the setup "process", cleanup after it.
				*/
				this.setupStop = () => {
				volumeMeterStop()

				// Unset the video element tracks
				if (setupVideoElement) {
				const mediaStream = new MediaStream()
				setupVideoElement.srcObject = mediaStream
				}
				}

				/**
				* Return current setup information
				*/
				this.setupData = () => {
				return {
				microphones,
				cameras,
				audioSource,
				videoSource,
				audioActive,
				videoActive
				}
				}

				/**
				* Change the publisher audio device
				*
				* @param deviceId Device identifier string
				*/
				this.setupSetAudio = async (deviceId) => {
				const mediaStream = setupVideoElement.srcObject

				if (!deviceId) {
				volumeMeterStop()
				this.removeTracksFromStream(mediaStream, 'Audio')
				audioActive = false
				audioSource = ''
				} else if (deviceId == audioSource) {
				volumeMeterStart()
				audioActive = true
				} else {
				const constraints = {
				audio: {
				deviceId: { ideal: deviceId }
				}
				}

				volumeMeterStop()

				// Stop and remove the old track, otherwise you get "Concurrent mic process limit." error
				this.removeTracksFromStream(mediaStream, 'Audio')

				// TODO: Error handling

				const track = await this.getTrack(constraints)

				mediaStream.addTrack(track)
				volumeMeterStart()
				audioActive = true
				audioSource = deviceId
				}

				return audioActive
				}

				/**
				* Change the publisher video device
				*
				* @param deviceId Device identifier string
				*/
				this.setupSetVideo = async (deviceId) => {
				const mediaStream = setupVideoElement.srcObject

				if (!deviceId) {
				this.removeTracksFromStream(mediaStream, 'Video')
				// Without the next line the video element will freeze on the last video frame
				// instead of turning black.
				setupVideoElement.srcObject = mediaStream
				videoActive = false
				videoSource = ''
				} else if (deviceId == audioSource) {
				videoActive = true
				} else {
				const constraints = {
				video: {
				deviceId: { ideal: deviceId }
				}
				}

				// Stop and remove the old track, otherwise you get "Concurrent mic process limit." error
				this.removeTracksFromStream(mediaStream, 'Video')

				// TODO: Error handling

				const track = await this.getTrack(constraints)

				mediaStream.addTrack(track)
				videoActive = true
				videoSource = deviceId
				}

				return videoActive
				}

				/**
				* Removes tracks of specified kind (audio or video) from a stream
				*/
				this.removeTracksFromStream = (stream, type) => {
				if (stream) {
				type = type.replace(/^a/, 'A').replace(/^v/, 'V')
				stream[`get${type}Tracks`]().forEach(track => {
				track.stop()
				stream.removeTrack(track)
				})
				}
				}

				/**
				* Starts volume changes tracking on the setup video element
				*/
				const volumeMeterStart = () => {
				if (!setupVolumeElement) {
				return
				}

				const audioContext = new AudioContext()
				const source = audioContext.createMediaStreamSource(setupVideoElement.srcObject)

				// Create a new volume meter
				const processor = audioContext.createScriptProcessor(512)

				processor.volume = 0
				processor.averaging = 0.95

				processor.onaudioprocess = function(event) {
				let buf = event.inputBuffer.getChannelData(0)
				let bufLength = buf.length
				let sum = 0

				// Do a root-mean-square on the samples: sum up the squares...
				for (let x, i=0; i<bufLength; i++) {
				x = buf[i]
				sum += x * x
				}

				// ... then take the square root of the sum.
				const rms = Math.sqrt(sum / bufLength)

				// Now smooth this out with the averaging factor applied
				// to the previous sample - take the max here because we
				// want "fast attack, slow release."
				this.volume = Math.max(rms, this.volume * this.averaging)
				}

				processor.shutdown = function() {
				this.disconnect()
				this.onaudioprocess = null
				}

				// this will have no effect, since we don't copy the input to the output,
				// but works around a current Chrome bug.
				processor.connect(audioContext.destination)

				// Connect the volume processor to the source
				source.connect(processor)

				const update = () => { volumeMeterUpdate(processor.volume * 100) }

				this.audioContext = audioContext
				this.volumeInterval = setInterval(update, 25)
				}

				/**
				* Stops volume changes tracking on the setup video element
				*/
				const volumeMeterStop = () => {
				if (this.audioContext) {
				clearInterval(this.volumeInterval)
				this.audioContext.close()
				this.audioContext = null
				volumeMeterUpdate(0)
				}
				}

				/**
				* Updates volume meter widget on voluma level change
				*/
				const volumeMeterUpdate = (volume) => {
				const value = Math.min(100, Math.ceil(volume))
				const bar = setupVolumeElement.firstChild

				let color = 'lime'
				if (value >= 70) {
				color = '#ff3300'
				} else if (value >= 50) {
				color = '#ff9933'
				}

				bar.style.height = value + '%'
				bar.style.background = color
				}
				}

				export { Media }