bowling-analysis-system/src/core/metrics/EventPositions.js

A comprehensive system for analyzing bowling techniques using video processing and metrics calculation

/**
 * @module core/metrics/EventPositions
 * @description Calculate event positions from valid frames
 */

const { findFrameIndexByEvent } = require('../utils/FrameUtils');

/**
 * Calculate positions at key events
 * @param {Array} validFrames - Array of valid frames
 * @param {Object} events - Detected events
 * @returns {Object} Position metrics
 */
function calculateEventPositions(validFrames, events) {
  const positions = {};
  
  console.log('Starting event positions calculation');
  console.log(`Valid frames: ${validFrames.length}`);
  console.log('Events:', Object.keys(events).join(', '));
  
  // Calculate positions at release point
  if (events.releasePoint && validFrames.length > 0) {
    console.log('Found release point event');
    const releaseIndex = events.releasePoint.frameIndex;
    console.log(`Release index: ${releaseIndex}`);
    
    // Find the release frame or the closest frame to it using the centralized utility
    const releaseFrameIndex = findFrameIndexByEvent(validFrames, events.releasePoint, 'index');
    
    if (releaseFrameIndex >= 0) {
      console.log(`Release frame index in validFrames: ${releaseFrameIndex}`);
      
      // Get the frame data
      const frame = validFrames[releaseFrameIndex];
      
      // Calculate release position
      if (frame.pose_landmarks && frame.pose_landmarks[0]) {
        const landmarks = frame.pose_landmarks[0];
        
        // Check if we have all required landmarks
        if (landmarks[0] && landmarks[11] && landmarks[12] && landmarks[15] && landmarks[16]) {
          console.log('All required landmarks are present');
          
          // Get the wrist position (average of left and right wrists)
          const leftWrist = landmarks[15];
          const rightWrist = landmarks[16];
          
          positions.releasePosition = {
            x: (leftWrist[0] + rightWrist[0]) / 2,
            y: (leftWrist[1] + rightWrist[1]) / 2,
            z: (leftWrist[2] + rightWrist[2]) / 2
          };
          
          // Get the head position
          const head = landmarks[0];
          positions.headPosition = {
            x: head[0],
            y: head[1],
            z: head[2]
          };
          
          // Get the shoulder position (average of left and right shoulders)
          const leftShoulder = landmarks[11];
          const rightShoulder = landmarks[12];
          
          positions.shoulderPosition = {
            x: (leftShoulder[0] + rightShoulder[0]) / 2,
            y: (leftShoulder[1] + rightShoulder[1]) / 2,
            z: (leftShoulder[2] + rightShoulder[2]) / 2
          };
        }
      }
    } else {
      console.log('No valid release frame found');
    }
  }
  
  // Calculate positions at foot landing
  if (events.frontFootLanding && validFrames.length > 0) {
    // Similar approach using findFrameIndexByEvent for front foot landing
    const landingFrameIndex = findFrameIndexByEvent(validFrames, events.frontFootLanding, 'index');
    
    if (landingFrameIndex >= 0) {
      const frame = validFrames[landingFrameIndex];
      
      // Calculate foot position
      if (frame.pose_landmarks && frame.pose_landmarks[0]) {
        const landmarks = frame.pose_landmarks[0];
        
        // Check if we have foot landmarks
        if (landmarks[27] && landmarks[28]) {
          // Get the foot position (average of left and right ankles)
          const leftAnkle = landmarks[27];
          const rightAnkle = landmarks[28];
          
          positions.footPosition = {
            x: (leftAnkle[0] + rightAnkle[0]) / 2,
            y: (leftAnkle[1] + rightAnkle[1]) / 2,
            z: (leftAnkle[2] + rightAnkle[2]) / 2
          };
        }
      }
    }
  }
  
  console.log('Finished event positions calculation');
  console.log('Position metrics:', Object.keys(positions).join(', '));
  
  return positions;
}

module.exports = {
  calculateEventPositions
};