change_img.py 文件源码

def read_image(filename):
    f = open(filename, 'rb')
    index = 0
    buf = f.read()
    f.close()

    magic, images, rows, columns = struct.unpack_from('>IIII' , buf , index)
    index += struct.calcsize('>IIII')
    for i in xrange(images):
        #for i in xrange(2000):
        image = Image.new('L', (columns, rows))

        for x in xrange(rows):
            for y in xrange(columns):
                image.putpixel((y, x), int(struct.unpack_from('>B', buf, index)[0]))
                index += struct.calcsize('>B')


        print 'save ' + str(i) + 'image'
        image.save('./test/' + str(i) + '.png')