import os
import re
import sys

directory = sys.argv[1]

jpeg_files = subprocess.check_output(["ls", "%s/*.jpg" % directory], shell=True).rstrip().split("\n")

for jpeg_file in jpeg_files:
    png_file = re.sub(r"jpg$", "png", jpeg_file)

    command = "convert %s %s" % (jpeg_file, png_file)

    print "Running '%s'..." % command

    subprocess.call(command)