import StringIO, gzip, base64
zbuf = StringIO.StringIO()
zfile = gzip.GzipFile(mode="wb",fileobj=zbuf)
zfile.write(open("my.jpg","rb").read())
zfile.close()
open("rez_img.txt", "w").write(base64.encodestring(zbuf.getvalue()))

def decode():
    with open("rez_img.txt") as f:
        buf = StringIO.StringIO(f.read().decode('base64'))
        return gzip.GzipFile(fileobj=buf).read()