Convert JPG to JPX

It is most likely possible to achieve jpg to jpx conversion using one of the graphics editors or converters, but it is more or less pointless conversion. This is due the fact that JPEG 2000 (.jpx) is more sophisticated format and thus has more data when you record in that format, so converting into it from inferior format won't do any good. You will have to use a RAW source of the JPG image if you want to create a proper JPEG 2000 image.