Help with simple plugin development

Hi everyone,

I wrote a simple lua plugin for koreader, enabling a "double screen refresh" when reading.

This can help with reading color mangas/comics to limit ghosting.

But, I would like the plugin to do something only if what is actually displayed is a color image. (At the moment, the "double refresh" is always active, event on text or black and white images).

And I don't know how to do that. My color files in cbz archives contains "_color" in their names so I thought instead of analysing the picture pixel by pixel (probably a bad idea on a e-reader), simply checking the name of the image currently displayed would be a "good" way to go, but I have no idea how to get the name of the image displayed in my lua plugin.

If someone could help me on this one, it would be very nice :)

Thanks