@virtualman
If you have all artworks present, then take one working artwork file. check resolution and file extension.
use a graphics tool like
irfanview with batch conversion, to resize all artwork files to same resolution and file extension.
or don't you have not all artwork files (after scrape artwork by AM itself)?
got this problem with missing marquee files.
I'm not using a RPI (i'm using Windows system), but maybe it helps you.
all my covers are .png
my path to attract.exe is : C:\attract\attract.exe
to figure out, which snes romfile doesn't have a own marquee art in AM scraper folder (just customize to your settings)
then create/copy artwork manually in AM scraper folder.
Create a batch-file with this:
@echo off
cd C:\attract\EMU\zsnes\roms
for %%i in (*.smc) do (
if not exist C:\attract\scraper\zsnes\marquee\%%~ni.png echo %%i
)
echo.
pause