poseLandmarkerSmoothing.ts

import {
	PoseLandmarker,
	type NormalizedLandmark,
	type PoseLandmarkerResult
} from '@mediapipe/tasks-vision'

const poseLandmarker: PoseLandmarker
let prevSmoothedLandmarks: NormalizedLandmark[] = []
const smoothingFactor = 0.75

/// initialize pose landmarker

poseLandmarker.detectForVideo(
			videoElement,
  
			startTimeMs,
			(result: PoseLandmarkerResult) => {
				const smoothedLandmarks = this.smoothLandmarks(
					result.landmarks[0],
					prevSmoothedLandmarks,
					smoothingFactor
				)
				prevSmoothedLandmarks = smoothedLandmarks
				const resultWithSmoothedLandmarks = {
					...result,
					landmarks: [smoothedLandmarks]
				}

				// use the new result
			}
		)

smoothLandmarks(
		currentLandmarks: NormalizedLandmark[],
		prevSmoothedLandmarks: NormalizedLandmark[],
		smoothingFactor: number
	) {
		if (prevSmoothedLandmarks.length === 0) {
			// Initial case, no smoothing needed
			return currentLandmarks
		}

		// Smooth each landmark
		const smoothedLandmarks = currentLandmarks.map((currentLandmark, i) => {
			const prevSmoothedLandmark = prevSmoothedLandmarks[i]
			return {
				x: (1 - smoothingFactor) * currentLandmark.x + smoothingFactor * prevSmoothedLandmark.x,
				y: (1 - smoothingFactor) * currentLandmark.y + smoothingFactor * prevSmoothedLandmark.y,
				z: (1 - smoothingFactor) * currentLandmark.z + smoothingFactor * prevSmoothedLandmark.z
			}
		})

		return smoothedLandmarks
	}