Create a 4:3 canvas and pop the animation in the middle, the canvas will be scaled to fullscreen, the animation will maintain aspect ratio. If you need the 256 to stretch to the full width arrange it like that on the canvas, if you need 256 to be padded, ie background on either side, make your canvas fullscreen res and dropthe anim in with no scale increase.
That work?
hi,
you could mess around with the screensetup.xml file.
the screen settings are stored in this file. When in screensetup Resolume only shows the resolutions supported by your hardware, so you can't specify a custom size.
But most of the times it can perform on any resolution, so open the screensetup.xml file before you start resolume, change the process and output resolution to 256*48 and see what happens. You can't break anything, if you made a mess of the file just delete it and resolume will start in default mode and create a new file for you to mess around with.