<> This page contains utilities. = Making bitmaps transparent = Cu_alpha is a very small and simple utility for creating transparent bitmaps. == What it does == Cu_alpha makes one color of a bitmap transparent. Being a bit more precise: ca_alpha eats all .tif and .bmp files from a directory and writes .png files in a lossless way into another directory with either black or white as transparent alpha channel. == Uses == Ortho rectified images contain empty parts you don't want to see in your CAD program, so you make these parts transparent. Other uses: Make logo's transparent for web use. Make scanned black and white drawings transparent. Etcetera. == Tech == The program is nothing more than a batch file named cu_alpha.bat. It is used to generate some input panels and to tell a program convert.exe what to do. The batch file relies on two programs: "!ImageMagick" and "The Wizard's Apprentice". Credits go to these projects, url's: http://www.imagemagick.org/ and http://wizapp.sourceforge.net/. == Limitations == Only a Windows version. If source files share the same name with a different extension, only .bmp will be processed. abc.tif and abc.bmp will be transformed to abc.png where abc.tif is ignored. == Installation == * No installer, download [[attachment:cu_alpha.zip]] * Unzip (for example to c:\bin\) * Make a desktop shortcut to cu_alpha.bat (right click on Desktop, etc.) * Optionally Ctrl+drag the shortcut to your start menu button. = All files = See [[Downloads]] for the zip file.