Function hand_tracking_visualizer

examples/08_stream_audio_file.py:12–85

Visualize hand tracking data in 3D space

(streamer)

import array

def hand_tracking_visualizer(streamer):
    """Visualize hand tracking data in 3D space"""
    
    def generate_frame(blank_frame):
        h, w = blank_frame.shape[:2]
        
        # Dark background
        blank_frame[:] = [20, 20, 20]
        
        # Get latest hand tracking data
        latest = streamer.get_latest()
        if latest is None:
            cv2.putText(blank_frame, "Waiting for hand data...", (w//2 - 200, h//2),
                        cv2.FONT_HERSHEY_SIMPLEX, 1, (255, 255, 255), 2)
            return blank_frame
        
        # Draw virtual 3D space
        center_x, center_y = w // 2, h // 2
        
        # Draw coordinate axes
        cv2.line(blank_frame, (center_x, center_y), (center_x + 100, center_y), (0, 0, 255), 2)
        cv2.line(blank_frame, (center_x, center_y), (center_x, center_y - 100), (0, 255, 0), 2)
        cv2.putText(blank_frame, "X", (center_x + 110, center_y), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (0, 0, 255), 2)
        cv2.putText(blank_frame, "Y", (center_x, center_y - 110), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (0, 255, 0), 2)
        
        # Project and draw hand positions
        left_wrist = latest.get("left_wrist")
        right_wrist = latest.get("right_wrist")
        left_fingers = latest.get("left_fingers")
        right_fingers = latest.get("right_fingers")
        
        # Draw left hand
        if left_wrist is not None and left_fingers is not None:
            left_fingers_world = left_wrist @ left_fingers
            lx, ly = int(center_x + float(left_wrist[0, 0, 3]) * 400), int(center_y - float(left_wrist[0, 1, 3]) * 400)
            left_pinch = latest.get("left_pinch_distance", 0)
            color = (0, 255, 0) if left_pinch < 0.02 else (100, 100, 255)
            cv2.circle(blank_frame, (lx, ly), 15, color, -1)
            cv2.putText(blank_frame, "L", (lx - 8, ly + 5), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 255, 255), 2)
            
            for i in range(left_fingers_world.shape[0]):
                fx = int(center_x + float(left_fingers_world[i, 0, 3]) * 400)
                fy = int(center_y - float(left_fingers_world[i, 1, 3]) * 400)
                cv2.circle(blank_frame, (fx, fy), 3, (150, 150, 255), -1)
        
        # Draw right hand
        if right_wrist is not None and right_fingers is not None:
            right_fingers_world = right_wrist @ right_fingers
            rx, ry = int(center_x + float(right_wrist[0, 0, 3]) * 400), int(center_y - float(right_wrist[0, 1, 3]) * 400)
            right_pinch = latest.get("right_pinch_distance", 0)
            color = (0, 255, 0) if right_pinch < 0.02 else (255, 100, 100)
            cv2.circle(blank_frame, (rx, ry), 15, color, -1)
            cv2.putText(blank_frame, "R", (rx - 8, ry + 5), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 255, 255), 2)
            
            for i in range(right_fingers_world.shape[0]):
                fx = int(center_x + float(right_fingers_world[i, 0, 3]) * 400)
                fy = int(center_y - float(right_fingers_world[i, 1, 3]) * 400)
                cv2.circle(blank_frame, (fx, fy), 3, (255, 150, 150), -1)