PNG images take much longer to process than JPG

[bublath]

Processing of PNG images takes up to 10s and a lot of CPU is consumed, while after converting the image to JPG processing is almost instantly.

[sciurius]

This is a known issue. It is related to the way transparancy is handled in the PNG image.

If you run chordpro installed from CPAN, you can install Image::PNG::Libpng and it should improve.

[bublath]

Ok. If that's known it's alright. The documentation in https://www.chordpro.org/chordpro/directives-image/
explicitely suggest PNG, so maybe hint to use JPG in case performance is seen as an issue. I'm just using JPG going forward. Problem solved.