When you load a 4-bit (16 color) BMP file into XnView 1.93.2, the status bar lists it as a 8-bit (256 color) file. This can be verified with this image:
http://www-public.tu-bs.de:8080/~y00113 ... 4x24x4.bmp
Are be creating a 4-bit BMP e.g. using IrfanView.
1.93.2: 4-bit BMPs displayed as 8-bit
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