handdist.py

import cv2
from cvzone.HandTrackingModule import HandDetector
detector=HandDetector(detectionCon=0.5,maxHands=1)
width=640
height=480
Known_distance = 50.0
Known_width = 9.0

cap=cv2.VideoCapture(0)
a=[]
def Focal_Length_Finder(Known_distance, real_width, width_in_rf_image):

    focal_length = (width_in_rf_image * Known_distance) / real_width
    return focal_length
def obj_data(img):
    obj_width=0
    hands,frame=detector.findHands(img)
    if hands:
        hands1=hands[0]
        bbox=hands1["bbox"]
        x,y,w,h=bbox
        a.append([x,y])
        obj_width=w
    return obj_width
def Distance_finder(Focal_Length, Known_width, obj_width_in_frame):
    distance = (Known_width * Focal_Length)/obj_width_in_frame
    return distance
ref_image = cv2.imread("rf.png")
ref_image_obj_width = obj_data(ref_image)
Focal_length_found = Focal_Length_Finder(Known_distance, Known_width, ref_image_obj_width)
cv2.imshow("ref_image", ref_image)

print(Focal_length_found)
        

while True:
    ret,frame=cap.read()
    frame=cv2.flip(frame,1)
    obj_width_in_frame=obj_data(frame)
    if not obj_width_in_frame:
        print("no hands")
    else:    
        Distance = Distance_finder(Focal_length_found, Known_width, obj_width_in_frame)
        for i in a:
            x1=i[0]
            y1=i[1]
          
        cv2.putText(frame, f"Distance: {round(Distance,2)} CM", (x1, y1),cv2.FONT_HERSHEY_PLAIN, 2, (255,0,0), 2)
       
   
        
    frame=cv2.imshow("FRAME",frame)
   
    if cv2.waitKey(1)&0xFF==27:
        break
cap.relase()
cv2.destroyAllWindows()