Geert Maene wrote in news:khmdg.447153
:

Who knows a simple software to edit nautical charts. I have mad a scan
of my chart.



As you "scan" is probably a picture file of a chart, you should be able to
change the picture with picture editing software, copy and pasting tiny
pictures of the chart symbols into it, I suppose.

There are lots of picture editors that can change a picture at the pixel
level. Some of them are free.