NameError : face_section not defined

#1

import cv2
import numpy as np

cap = cv2.VideoCapture(0)
skip = 0
face_data =[]
dataset_path ="./data/"

face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades+“haarcascade_frontalface_alt.xml”)

while True:
ret,frame = cap.read()
gray_frame = cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)

if ret == False:
    continue

faces = face_cascade.detectMultiScale(frame,1.3,5)
faces = sorted(faces,key=lambda f:f[2]*f[3])
for face in faces[-1:]:
    x,y,w,h = face
    cv2.rectangle(frame,(x,y),(x+w,y+h),(0,255,255),2)
    offset = 10
    face_section = frame[y-offset:y+h+offset,x-offset:x+w+offset]
    face_section= cv2.resize(face_section,(100,100))
    skip = skip + 1
    if skip % 10 == 0:
        face_data.append(face_section)
        print(len(face_data))
cv2.imshow("Frame",frame)
cv2.imshow("Face Section",face_section)

key_pressed = cv2.waitKey(1) & 0xFF
if key_pressed == ord('q'):
    break

cap.release()
cv2.destroyAllWindows()

Sir the above program is not getting executed with the error that the face sedtion is not defined

and when I remove “cv2.imshow('face Section”,face_section) " from the program it get executed but the program is not getting terminated successfully, Every time i have to restart the command prompt,after each execution.

please Help

#2

hey @naman_kr_301 ,

This might be because you are declaring face section inside your for loop. So face section will only be declared of there are some faces detected and hence , when there are no faces detected , means no for loop and no declaration of face selection variable hence it gives error.

It is because you are running an infinite loop which can be breaked like this. For this you need to add a break command or something.

I hope this would have cleared your doubt.
Thank You and Happy Learning :slightly_smiling_face:.

#3

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