import os, sys, cv2
from glob import glob

################# main ########################################
if __name__ == '__main__' :
   
    if len(sys.argv) > 3  :
        srcFiles = sys.argv[1] + "\*." + sys.argv[2]
        srcFilesList = [f for f in glob(srcFiles)]

        for srcFile in srcFilesList :
            srcImg = cv2.imread(srcFile)
            #cv2.imshow("Source",srcImg)

            srcString = "."+sys.argv[2]
            targetString = "."+sys.argv[3]
            targetImg = srcFile.replace(srcString, targetString)
            cv2.imwrite(targetImg, srcImg)
    else :
        print('Usage: python image_converter.py folder_name source_image_format target_image_format')
        print('python image_converter.py carimagesfolder png jpg')