jiti-meet/react/features/facial-recognition/facialExpressionsWorker.js

160 lines
3.8 KiB
JavaScript

import './faceApiPatch';
import { setWasmPaths } from '@tensorflow/tfjs-backend-wasm';
import * as faceapi from '@vladmandic/face-api';
import { DETECTION_TYPES, DETECT_FACE, INIT_WORKER } from './constants';
/**
* Detection types to be applied.
*/
let faceDetectionTypes = [];
/**
* Indicates whether an init error occured.
*/
let initError = false;
/**
* A flag that indicates whether the models are loaded or not.
*/
let modelsLoaded = false;
/**
* A flag that indicates whether the tensorflow backend is set or not.
*/
let backendSet = false;
/**
* Flag for indicating whether a face detection flow is in progress or not.
*/
let detectionInProgress = false;
/**
* Contains the last valid face bounding box (passes threshold validation) which was sent to the main process.
*/
let lastValidFaceBox;
const detectFaceBox = async ({ detections, threshold }) => {
if (!detections.length) {
return null;
}
const faceBox = {
// normalize to percentage based
left: Math.round(Math.min(...detections.map(d => d.relativeBox.left)) * 100),
right: Math.round(Math.max(...detections.map(d => d.relativeBox.right)) * 100)
};
faceBox.width = Math.round(faceBox.right - faceBox.left);
if (lastValidFaceBox && Math.abs(lastValidFaceBox.left - faceBox.left) < threshold) {
return null;
}
lastValidFaceBox = faceBox;
return faceBox;
};
const detectFaceExpression = async ({ detections }) =>
detections[0]?.expressions.asSortedArray()[0].expression;
const detect = async ({ image, threshold }) => {
let detections;
let faceExpression;
let faceBox;
detectionInProgress = true;
faceapi.tf.engine().startScope();
const imageTensor = faceapi.tf.browser.fromPixels(image);
if (faceDetectionTypes.includes(DETECTION_TYPES.FACE_EXPRESSIONS)) {
detections = await faceapi.detectAllFaces(
imageTensor,
new faceapi.TinyFaceDetectorOptions()
).withFaceExpressions();
faceExpression = await detectFaceExpression({ detections });
}
if (faceDetectionTypes.includes(DETECTION_TYPES.FACE_BOX)) {
detections = detections
? detections.map(d => d.detection)
: await faceapi.detectAllFaces(imageTensor, new faceapi.TinyFaceDetectorOptions());
faceBox = await detectFaceBox({
detections,
threshold
});
}
faceapi.tf.engine().endScope();
if (faceBox || faceExpression) {
self.postMessage({
faceBox,
faceExpression
});
}
detectionInProgress = false;
};
const init = async ({ baseUrl, detectionTypes }) => {
faceDetectionTypes = detectionTypes;
if (!backendSet) {
try {
if (self.useWasm) {
setWasmPaths(baseUrl);
await faceapi.tf.setBackend('wasm');
} else {
await faceapi.tf.setBackend('webgl');
}
backendSet = true;
} catch (err) {
initError = true;
return;
}
}
// load face detection model
if (!modelsLoaded) {
try {
await faceapi.loadTinyFaceDetectorModel(baseUrl);
if (detectionTypes.includes(DETECTION_TYPES.FACE_EXPRESSIONS)) {
await faceapi.loadFaceExpressionModel(baseUrl);
}
modelsLoaded = true;
} catch (err) {
initError = true;
return;
}
}
};
onmessage = function(message) {
switch (message.data.type) {
case DETECT_FACE: {
if (!backendSet || !modelsLoaded || initError || detectionInProgress) {
return;
}
detect(message.data);
break;
}
case INIT_WORKER: {
init(message.data);
break;
}
}
};