Used Iconc for Windows?
Developer’s Description
By Exoton
Images can be in any format supported by GDI+ (BMP, GIF, JPEG, PNG, TIFF), but in the generated icon file they are always in the PixelFormat32bppARGB format. Images bigger than 128x128 pixels are copied as is (PNG should work).
The source code is released under the very permissive MIT license, and for those who cannot build it from the source code, we've included signed binaries (32- and 64-bit) for Windows XP and above.
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