Filters Reduce PPI on PNG Files

When I run filters on PNG files the PPI is reduced from 300x300 to 72x72, I am unable to find a setting to override this behavior.

Example settings
gmic.exe input.png fx_blackandwhite 0.3,0,0.3,0,0.3,0,6,6,6,0,-18,18,18,18,1,3,3,3,6,3,3,0,0,50,50 -o output.png

If I convert the file to JPG first the PPI is maintained.

I would greatly appreciate any guidance available.

@RodneyEbanks Welcome to the forum!

G’MIC is only concerned with the pixels and may break the tagging. I don’t recall output having any options for PNG tagging. You may have to reinsert the PPI-related tags after saving; e.g., using exiftool.

Thanks