FMEUniversalReader from a file like object?

I have a texture embedded in a binary file. I’m trying to extract the textures and apply them to the geometry I’m loading. 

I figured the easiest way to do this is to read the textures in with the FMEUniversalReader. I quickly found out that I need to pass the input file as a string (filename). Ideally I’d pass this as just a BytesIO object as the library I’m working with already loads the data as a PIL object.

At this point I don’r really see a way around writing out the textures to disk and then reading them again with FME. 

Any other ideas?