I made 18 decals for no signal but I didn't want to export all of them manually. So, I tried to figure out how to export krita images in bulk. According to krita --help, there is an --export and a --export-filename flag that I would expect to work. I figure out how to use these flags:

krita 1a.kra --export --export-filename 1a.png

However, Krita just exports an empty image. According to the Krita documentation, the --export flag should work for this:

Krita documentation

This is primarily used in bash or shell scripts, for example, to mass convert KRA files into PNGs.

Through internet searches, I find out that you can also export the PNG by treating the Krita file as a zip. I found a Krita mass export repository treating the Krita file as a zip archive, which says that the file is named mergedimage.png and that it is in the first directory level:

voidcase/krita_exporter

def export_kra(src: T.Union[str, Path], dst: T.Union[str, Path]):
    with ZipFile(src) as src_zip:
        src_zip.extract('mergedimage.png', '/tmp/')
        Path('/tmp/mergedimage.png').rename(dst)

I don't want to figure out how to run this repository, so I look for a way to extract a specific file from a zip instead:

unix.stackexchange.com

unzip -p myarchive.zip path/to/zipped/file.txt >file.txt

This gives me the following command, which works!

unzip -p 1a.kra mergedimage.png >1a.png