icnsutil and Xcode's automatic iconset -> icns conversion recompress their input files, even if they were already in the correct format. This would be fine, except for that they do an extremely poor job of compressing to png and produce files twice as large as can be achieved with better compressors. This tool simply packs a .iconset into a .icns with no recompression (and not much in the way of validation, so make sure the end result works).
Compile using CMake. Run with icnspack output.icns input.iconset.
Example: icnspack assets/icons.icns assets/icon.iconset
Here are two tools to open icns files directly in your browser. Both tools can be used either with an icns file or a rgb / argb image file.
Copyright (c) 2014, Thomas Goyne tgoyne@gmail.com
Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
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