Expected Ptr<cv::UMat> for argument '%s'

Question

I am not able to proceed after this step

 f='/content/drive/My Drive/resized'
    f_len=len(f)
    os.mkdir('grayscale20')
    for image in os.listdir(f):
    
        img=os.path.join(f,image)
                
        img = cv2.imread(f)
        grayImg = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
        #grayImg = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
        cv2.imwrite("grayscale",+f[folderLen:],grayImg)
    cv2.destroyAllWindows   
    
    
    

Please refer to these pics
1 2

Answer 1

而不是img = cv2.imread(f)你应该使用img = cv2.imread(img)