mathSolver.py

import cv2 as cv
import mediapipe as mp
import numpy as np
import time

mp_drawing = mp.solutions.drawing_utils
mp_hands = mp.solutions.hands
hands = mp_hands.Hands(max_num_hands=2, min_detection_confidence=0.7,
    min_tracking_confidence=0.7)

#To find distance between two points
def euclidean_distance(p1, p2):
    return np.sqrt((p1.x - p2.x) ** 2 + (p1.y - p2.y) ** 2)

#To identify gestures for different operations
def detectGesture(hand1_data, hand2_data):
    (hand1, label1), (hand2, label2) = hand1_data, hand2_data
    f1 = count_fingers(hand1, label1)
    f2 = count_fingers(hand2, label2)
    dist = euclidean_distance(hand1.landmark[8], hand2.landmark[8])
    if f1==1 and f2==1:
        if dist < 0.06:
            return "exit"
        return "+"
    elif (f1==1 and f2==2) or (f1==2 and f2==1):
        return "-"
    elif (f1==1 and f2==3) or (f1==3 and f2==1):
        return "*"
    elif (f1==1 and f2==4) or (f1==4 and f2==1):
        return "/"
    elif (f1==2 and f2==2):
        return "del"
    elif (f1+f2==6):
        return "6"
    elif (f1+f2==7):
        return "7"
    elif (f1+f2==8):
        return "8"
    elif (f1+f2==9):
        return "9"
    elif f1==0 and f2==0:
        return "="
    elif f1==5 and f2==5:
        return "clear"
    return None

#counting the fingers that are up
def count_fingers(hand_landmarks, label):
    tip_ids = [4,8,12,16,20]
    fingers = []
    if label=="Left":
        fingers.append(1 if hand_landmarks.landmark[tip_ids[0]].x > hand_landmarks.landmark[tip_ids[0]-1].x else 0)
    else:
        fingers.append(1 if hand_landmarks.landmark[tip_ids[0]].x < hand_landmarks.landmark[tip_ids[0]-1].x else 0)
    for ids in range(1,5):
        if hand_landmarks.landmark[tip_ids[ids]].y < hand_landmarks.landmark[tip_ids[ids]-2].y:
            fingers.append(1)
        else:
            fingers.append(0)
    return fingers.count(1)

#Initialising variables
last_finger_count = None
last_update_time = 0
delay = 1.25
expression=""
res=""

# For webcam input:
cap = cv.VideoCapture(0)
while True:
    success, image = cap.read()
    image = cv.flip(image, 1)
    img_rgb = cv.cvtColor(image, cv.COLOR_BGR2RGB)
    result = hands.process(img_rgb)
    current_time = time.time()
    hand_data=[]
    
    #Reading hand data and mapping it on the screen
    if result.multi_hand_landmarks and result.multi_handedness:
        for hand_landmarks, hand_handedness in zip(result.multi_hand_landmarks, result.multi_handedness):
            label = hand_handedness.classification[0].label
            hand_data.append((hand_landmarks,label))
            mp_drawing.draw_landmarks(image, hand_landmarks, mp_hands.HAND_CONNECTIONS)
        
        #Reading single and multi-hand data   
        if len(hand_data)==1:
            hand_landmarks, label = hand_data[0]
            fingers_up = count_fingers(hand_landmarks, label)
            if fingers_up in [0, 1, 2, 3, 4, 5] and current_time - last_update_time > delay:
                expression += str(fingers_up)
                last_update_time = current_time
                last_finger_count = fingers_up
        
        if len(hand_data)==2:
            gesture = detectGesture(hand_data[0], hand_data[1])
            
            #Clearing the screen
            if gesture=="clear":
                expression = ""
                res = ""
            
            #Exitting the window after 'x' sign
            if gesture == "exit":
                break 
            
            #Evaluating the result
            if gesture and current_time - last_update_time > delay:
                
                if gesture == "del":
                    expression = expression[:-1]
                    last_update_time = current_time
                    
                elif gesture=="=":
                    try:
                        res = str(eval(expression))
                        print("Result:", res)
                    except:
                        res = "Error"
                    last_update_time = current_time
                else:
                    expression+=gesture
                    last_update_time = current_time
     
    #Displaying the expression and result   
    cv.putText(image, f'Expr: {expression}', (10, 50), cv.FONT_HERSHEY_SIMPLEX, 1, (255,0,0), 2)
    cv.putText(image, f'Result: {res}', (10, 100), cv.FONT_HERSHEY_SIMPLEX, 1.2, (0,0,255), 2)
    cv.imshow("Math Solver", image)
    key = cv.waitKey(1) & 0xFF
    if key == ord('q') or key == 27:
        break
    elif key == ord('c'):
        expression=""
        res=""
        
#Releasing resources and closing the windows
cap.release()
cv.destroyAllWindows()