Python OpenCv2 将图像放在找到的脸上

Question

我正在加载几张图像会覆盖我的脸，我很难让图像通过创建的脸的正方形。 我查看了许多资源，但由于某种原因，我在尝试遵循他们的方法时收到错误消息。

每次我这样做时，我都会收到一个错误

ValueError：无法将输入数组从形状 (334,334,3) 广播到形状 (234,234,3)

我认为图像可能太大了，但是我尝试调整它们的大小以查看它们是否适合但无济于事。

这是我的代码：

import cv2
import sys
import logging as log
import datetime as dt
from time import sleep
import os
import random 
from timeit import default_timer as timer


cascPath = "haarcascade_frontalface_default.xml"
faceCascade = cv2.CascadeClassifier(cascPath)
#log.basicConfig(filename='webcam.log',level=log.INFO)

video_capture = cv2.VideoCapture(0)
anterior = 0

#s_img = cv2.imread("my.jpg")

increment = 0

for filename in os.listdir("Faces/"):
    if filename.endswith(".png"): 
         FullFile = (os.path.join("Faces/", filename))
         #ret, frame = video_capture.read()
         frame = cv2.imread(FullFile, cv2.IMREAD_UNCHANGED)

         gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
         faces = faceCascade.detectMultiScale( gray,scaleFactor=1.1, minNeighbors=5, minSize=(30, 30)  )
         edges = cv2.adaptiveThreshold(gray, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 9, 9) 
         
         for (x, y, w, h) in faces:            
            roi_color = frame[y:( y ) + ( h ), x:x + w]
            status = cv2.imwrite('export/faces_detected'+ str( increment ) +'.png', roi_color)
            increment = increment + 1 

        
    else:
        continue

masks = []


for filename in os.listdir("export/"):
    if filename.endswith(".png"): 
         FullFile = (os.path.join("export/", filename))
         s_img = cv2.imread(FullFile)
         masks.append(s_img)


Start = timer()
End = timer()
MasksSize = len(masks)
nrand = random.randint(0, MasksSize -1 )

increment =  0

while True:
    if not video_capture.isOpened():
        print('Unable to load camera.')
        sleep(5)
        pass

    # Capture frame-by-frame
    ret, frame = video_capture.read()

    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

    faces = faceCascade.detectMultiScale(
        gray,
        scaleFactor=1.1,
        minNeighbors=5,
        minSize=(30, 30)
    )



    edges = cv2.adaptiveThreshold(gray, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 9, 9) 


    # Draw a rectangle around the faces
    for (x, y, w, h) in faces:
        if (End - Start) > 3:
            Start = timer()
            End = timer()
            nrand = random.randint(0, MasksSize -1 )


        # -75 and +20 added to fit my face
        cv2.rectangle(frame, (x, y - 75), (x+w, y+h+20), (0, 255, 0), 2)
        s_img = masks[nrand]  
        increment = increment + 1 
        #maskresize = cv2.resize(s_img, (150, 150))


        #frame[y:y+s_img.shape[0]  , x:x+s_img.shape[1]] = s_img # problem occurs here with 


        # ValueError: could not broadcast input array from shape (334,334,3) into shape (234,234,3)
        # I assume I am inserting somethign too big? 
        End = timer()
        


        


    if anterior != len(faces):
        anterior = len(faces)
        #log.info("faces: "+str(len(faces))+" at "+str(dt.datetime.now()))


    # Display the resulting frame
    cv2.imshow('Video', frame)
    #cv2.imshow('Video', cartoon)

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

    # Display the resulting frame
    cv2.imshow('Video', frame)

# When everything is done, release the capture
video_capture.release()
cv2.destroyAllWindows()

Answer 1

• 在以下行中，

frame[y:y+s_img.shape[0]  , x:x+s_img.shape[1]] = s_img 

您试图将s_img分配给具有不同形状的frame[y:y+s_img.shape[0] , x:x+s_img.shape[1]] 。

• 您可以通过打印形状来检查两者的形状（它会与错误中提到的形状相同）。
• 尝试将s_img重新整形为相同的形状，然后尝试分配。

请参阅此链接： https : //www.geeksforgeeks.org/image-resizing-using-opencv-python/

我使用此功能调整图像大小以进行缩放。

 def image_resize(image, width = None, height = None, inter = cv2.INTER_AREA): # initialize the dimensions of the image to be resized and # grab the image size dim = None (h, w) = image.shape[:2] # if both the width and height are None, then return the # original image if width is None and height is None: return image # check to see if the width is None if width is None: # calculate the ratio of the height and construct the # dimensions r = height / float(h) dim = (int(w * r), height) # otherwise, the height is None else: # calculate the ratio of the width and construct the # dimensions r = width / float(w) dim = (width, int(h * r)) # resize the image resized = cv2.resize(image, dim, interpolation = inter) # return the resized image return resized

然后后来被称为

 r= image_resize(s_img, height = h, width=w) frame[y:y+r.shape[0] , x:x+r.shape[1]] = r

答案也取自此处： Resize an image withoutdistort OpenCV