oldiconutil
In Mac OS X 10.6, Apple introduced support for PNG-compressed icon data in .icns files. In Mac OS X 10.8, Apple introduced support for Retina icons and the iconutil command-line tool for generating icons from a folder of PNG files.
However, iconutil only knows how to generate PNG-compressed icon data, which means that you can't use it to create a Retina icon that will still display properly on Mac OS X 10.5.
He’s written some code that converts .icns files to use JPEG 2000 internally instead of PNG, which makes them readable on Mac OS X 10.5. Kudos to Kusterer for figuring this out, and shame on Apple for silently breaking compatibility.
2 Comments
I'm very grateful that you did this.
For those of us who are not developers, please, could you take it one step further and give us a compiled tool that will run on the older OSes where the problem shows up.
That way, we can fix it ourselves, if necessary.
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