import cv2 import mediapipe as mp import numpy as np # ----- Helper Functions ----- def compute_distance(p1, p2): return np.hypot(p2[0] - p1[0], p2[1] - p1[1]) # ----- Configuration ----- CAMERA_INDICES = [0] # List of camera device indices FRAME_WIDTH = 1280 FRAME_HEIGHT = 720 PIXELS_PER_INCH = 20 # will be set by calibration PINCH_THRESHOLD = 40 # px to start touch RELEASE_THRESHOLD = 60 # px to end touch CIRCLE_TOUCH_THRESHOLD = 20 # px tolerance for circle touch # ----- Initialize Hand Detector ----- mp_hands = mp.solutions.hands mp_draw = mp.solutions.drawing_utils hands = mp_hands.Hands( static_image_mode=False, max_num_hands=1, min_detection_confidence=0.7, min_tracking_confidence=0.5 ) # ----- Global State ----- measuring = False # measurement in progress start_pt = None # measurement start point calibrating = False # pinch-based calibration flag cal_start = None # pinch calibration start point object_calibrating = False # object calibration flag cal_circle = None # reference circle (x,y,r) fingertip_idx_global = None # last detected fingertip position # ----- Per-camera Processing ----- def process_frame(frame): global measuring, start_pt, calibrating, cal_start, object_calibrating, cal_circle, PIXELS_PER_INCH, fingertip_idx_global frame_out = cv2.flip(frame, 1) h, w, _ = frame_out.shape # Hand detection rgb = cv2.cvtColor(frame_out, cv2.COLOR_BGR2RGB) rgb.flags.writeable = False results = hands.process(rgb) rgb.flags.writeable = True frame_vis = cv2.cvtColor(rgb, cv2.COLOR_RGB2BGR) fingertip_idx = None fingertip_mid = None if results.multi_hand_landmarks: hand = results.multi_hand_landmarks[0] mp_draw.draw_landmarks(frame_vis, hand, mp_hands.HAND_CONNECTIONS) # get index and middle finger tips and PIP joints idx_tip = hand.landmark[mp_hands.HandLandmark.INDEX_FINGER_TIP] idx_pip = hand.landmark[mp_hands.HandLandmark.INDEX_FINGER_PIP] mid_tip = hand.landmark[mp_hands.HandLandmark.MIDDLE_FINGER_TIP] mid_pip = hand.landmark[mp_hands.HandLandmark.MIDDLE_FINGER_PIP] ix, iy = int(idx_tip.x * w), int(idx_tip.y * h) mx, my = int(mid_tip.x * w), int(mid_tip.y * h) fingertip_idx = (ix, iy) fingertip_mid = (mx, my) fingertip_idx_global = fingertip_idx # draw fingertips cv2.circle(frame_vis, fingertip_idx, 8, (0,255,0), -1) cv2.circle(frame_vis, fingertip_mid, 8, (0,255,0), -1) # check extension index_ext = idx_tip.y < idx_pip.y middle_ext = mid_tip.y < mid_pip.y # if measurement in progress but fingers no longer both extended, stop measuring if measuring and not (index_ext and middle_ext): measuring = False # pinch distance pinch = compute_distance(fingertip_idx, fingertip_mid) cv2.putText(frame_vis, f"Pinch: {int(pinch)} px", (10,30), cv2.FONT_HERSHEY_SIMPLEX, 0.6, (0,255,0),2) # pinch calibration if calibrating: if pinch < PINCH_THRESHOLD and cal_start is None: cal_start = fingertip_idx print("Pinch calibration start set") elif pinch > RELEASE_THRESHOLD and cal_start is not None: cal_end = fingertip_idx px = compute_distance(cal_start, cal_end) inches = float(input("Enter actual distance between points (inches): ")) PIXELS_PER_INCH = px / inches print(f"Calibrated: {PIXELS_PER_INCH:.2f} px/inch") calibrating = False cal_start = None # measurement gesture elif not object_calibrating and index_ext and middle_ext: if pinch < PINCH_THRESHOLD and not measuring: measuring = True start_pt = fingertip_idx elif pinch > RELEASE_THRESHOLD and measuring: measuring = False # object calibration if object_calibrating and fingertip_idx is not None: hsv = cv2.cvtColor(frame_vis, cv2.COLOR_BGR2HSV) mask = cv2.inRange(hsv, np.array([10,100,100]), np.array([25,255,255])) masked = cv2.bitwise_and(frame_vis, frame_vis, mask=mask) gray = cv2.cvtColor(masked, cv2.COLOR_BGR2GRAY) gray = cv2.medianBlur(gray,5) circles = cv2.HoughCircles(gray, cv2.HOUGH_GRADIENT, 1.2, 100, param1=50, param2=30, minRadius=10, maxRadius=300) if circles is not None: circles = np.round(circles[0]).astype(int) touched = [(x,y,r) for x,y,r in circles if abs(compute_distance((x,y), fingertip_idx)-r) < CIRCLE_TOUCH_THRESHOLD] if touched: touched.sort(key=lambda c: abs(compute_distance((c[0],c[1]), fingertip_idx)-c[2])) x,y,r = touched[0] cal_circle = (x,y,r) PIXELS_PER_INCH = 2 * r print(f"Circle calib: {PIXELS_PER_INCH:.2f} px/inch") object_calibrating = False # permanent reference circle if cal_circle: cx,cy,cr = cal_circle cv2.circle(frame_vis,(cx,cy),cr,(0,0,255),2) cv2.drawMarker(frame_vis,(cx,cy),(0,0,255),cv2.MARKER_TILTED_CROSS,15,1) cv2.putText(frame_vis,f"Ref r={cr} px",(cx-cr,cy+cr+20),cv2.FONT_HERSHEY_SIMPLEX,0.5,(0,0,255),1) return frame_vis # ----- Main ----- def main(): caps = [] for idx in CAMERA_INDICES: cap = cv2.VideoCapture(idx) cap.set(cv2.CAP_PROP_FRAME_WIDTH, FRAME_WIDTH) cap.set(cv2.CAP_PROP_FRAME_HEIGHT, FRAME_HEIGHT) caps.append(cap) if not all(cap.isOpened() for cap in caps): print("Error: could not open all cameras") return print("Press 'c' for pinch calib, 'o' for circle calib, 'q' to quit.") while True: frames = [cap.read()[1] for cap in caps] frame = next((f for f in frames if f is not None), None) if frame is None: break # process full_view = process_frame(frame) # create proj output proj = np.zeros_like(full_view) if cal_circle: cx,cy,cr = cal_circle cv2.circle(proj,(cx,cy),cr,(0,0,255),2) if measuring and start_pt and fingertip_idx_global: cv2.line(proj, start_pt, fingertip_idx_global, (255,0,0),2) px = compute_distance(start_pt, fingertip_idx_global) inch = px/PIXELS_PER_INCH; cm = inch*2.54 mid = ((start_pt[0]+fingertip_idx_global[0])//2,(start_pt[1]+fingertip_idx_global[1])//2) cv2.putText(proj,f"{inch:.2f}in/{cm:.1f}cm",(mid[0]+10,mid[1]-10), cv2.FONT_HERSHEY_SIMPLEX,0.7,(255,0,0),2) # overlay proj onto debug debug = full_view.copy() # overlay ref circle if cal_circle: cx,cy,cr = cal_circle cv2.circle(debug,(cx,cy),cr,(0,0,255),2) # overlay measurement if measuring and start_pt and fingertip_idx_global: cv2.line(debug, start_pt, fingertip_idx_global, (255,0,0),2) cv2.putText(debug,f"{inch:.2f}in/{cm:.1f}cm",(mid[0]+10,mid[1]-10), cv2.FONT_HERSHEY_SIMPLEX,0.7,(255,0,0),2) # show windows cv2.imshow('Hand Measure', debug) cv2.imshow('Projector Output', proj) key = cv2.waitKey(1) & 0xFF if key == ord('q'): break elif key == ord('c'): global calibrating calibrating = True cal_start = None print("Entered pinch calibration mode.") elif key == ord('o'): global object_calibrating object_calibrating = True print("Entered circle calibration mode.") for cap in caps: cap.release() cv2.destroyAllWindows() if __name__ == '__main__': main()