Iconverter makes your old Amiga icons look right (posted 2021-07-14)
The way the Amiga handles icons changed a number of times over the history of the platform, with the result that many older icons don't look right on Amigas running later versions of the OS. I made a tool to convert these old icons so they look like they should on later Amigas: Iconverter.
Iconverter is a tool for converting old icons so they look as intended on Amigas running a more recent operating system.In particular Iconverter will convert OS 1.x and MagicWB icons to NewIcons format using the palette those icons were created for. (Also OS 2.0 - 3.1 icons, but those usually look correct without conversion.)
Note that you need to run the NewIcons extension or the new IconLib_46 on an AmigaOS 3.0 or 3.1 system in order to see the converted version of icons created by Iconverter. AmigaOS 3.1.4 and 3.2 will show them "out of the box".
Iconverter is a shell / command line tool written in standard C. As such, it should compile and run on any system that has a C compiler.