human/src/face/liveness.ts

47 lines
1.7 KiB
TypeScript

/**
* Anti-spoofing model implementation
*/
import { log, join, now } from '../util/util';
import type { Config } from '../config';
import type { GraphModel, Tensor } from '../tfjs/types';
import * as tf from '../../dist/tfjs.esm.js';
import { env } from '../util/env';
let model: GraphModel | null;
const cached: Array<number> = [];
let skipped = Number.MAX_SAFE_INTEGER;
let lastCount = 0;
let lastTime = 0;
export async function load(config: Config): Promise<GraphModel> {
if (env.initial) model = null;
if (!model) {
model = await tf.loadGraphModel(join(config.modelBasePath, config.face.liveness?.modelPath || '')) as unknown as GraphModel;
if (!model || !model['modelUrl']) log('load model failed:', config.face.liveness?.modelPath);
else if (config.debug) log('load model:', model['modelUrl']);
} else if (config.debug) log('cached model:', model['modelUrl']);
return model;
}
export async function predict(image: Tensor, config: Config, idx, count): Promise<number> {
if (!model) return 0;
const skipTime = (config.face.liveness?.skipTime || 0) > (now() - lastTime);
const skipFrame = skipped < (config.face.liveness?.skipFrames || 0);
if (config.skipAllowed && skipTime && skipFrame && (lastCount === count) && cached[idx]) {
skipped++;
return cached[idx];
}
skipped = 0;
return new Promise(async (resolve) => {
const resize = tf.image.resizeBilinear(image, [model?.inputs[0].shape ? model.inputs[0].shape[2] : 0, model?.inputs[0].shape ? model.inputs[0].shape[1] : 0], false);
const res = model?.execute(resize) as Tensor;
const num = (await res.data())[0];
cached[idx] = Math.round(100 * num) / 100;
lastCount = count;
lastTime = now();
tf.dispose([resize, res]);
resolve(cached[idx]);
});
}