Well, you could use a plugin like our MBS Plugin to read image from container and save it to a new file in a different format. BMP and JPEG are no problem.
FileMaker stores by default the original image in the container and sometimes a JPEG preview in addition.
I don't have a hundred bucks minimum for the plugin and it is creating a bmp from my jpg that is getting imported.
I would imagine that I should be able to actually get access to the jpg version? right?