当我运行cod时，矩形没有显示在帧上

Question

我在做一个人脸检测和识别程序。我试过改变笔划的数字和颜色，但仍然得到相同的结果。我希望看到一个矩形的脸时，检测到或看到一个脸上的框架

我的代码：

color = (255, 0, 0) #BGR 0-255 
stroke = 4
end_cord_x = x + w
end_cord_y = y + h
cv2.rectangle(frame, (x, y), (end_cord_x, end_cord_y), color, stroke)
subitems = smile_cascade.detectMultiScale(roi_gray)
for (ex,ey,ew,eh) in subitems:
    cv2.rectangle(roi_color,(ex,ey),(ex+ew,ey+eh),(0,255,0),2)

Answer 1

您的问题还不清楚，但请尝试在face_cascade.detectMultiScale()和smile_cascade.detectMultiScale()中设置scaleFactor和minNeighbors参数，以正确检测面部和微笑

代码：

import cv2  

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml') 
smile_cascade = cv2.CascadeClassifier('haarcascade_smile.xml')  

cap = cv2.VideoCapture(0) 

while True:  
    ret, frame = cap.read()  
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) 
    faces = face_cascade.detectMultiScale(gray, 1.3, 5) 

    for (x, y, w, h) in faces: 
        color = (255, 0, 0)
        stroke = 4
        end_cord_x = x + w
        end_cord_y = y + h
        cv2.rectangle(frame, (x, y), (end_cord_x, end_cord_y), color, stroke) 
        roi_gray = gray[y:y + h, x:x + w] 
        roi_color = frame[y:y + h, x:x + w] 
        smiles = smile_cascade.detectMultiScale(roi_gray, 2, 20) 

        for (sx, sy, sw, sh) in smiles: 
            cv2.rectangle(roi_color, (sx, sy), ((sx + sw), (sy + sh)), (0, 255, 0), 2) 

    cv2.imshow('Detected Face',frame) 

    # Wait for Esc key to stop 
    k = cv2.waitKey(30) & 0xff
    if k == 27: 
        break

cap.release() 
cv2.destroyAllWindows() 

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