@johand As long as you have pysical access to the module, you can extract the image. Then you would have to de-compile the code, which is some effort. If you think that this is a sufficient barrier, then you can go that way. And, as @livius said, this topic has been diesucssed in this forum as well as in forum.microtpython.org. So you are not alone, and I expect some methods to come up.