The VGAGRAY.DRV display driver maps the color in an image to a gray-scale palette with 16 shades of gray. This display driver provides a good monochrome representation of 256-color images on a standard VGA display. The gray-scale value used is determined from the RGB color based on the following color weights:
Gray_value = (2 × Red_value + 5 × Green_value + 1 × Blue_value) / 8
By default, the VGAGRAY.DRV display driver uses a linear palette, but it can be changed by adding a [DISPLAY] section to the WIN.INI file. When Windows is started with VGAGRAY.DRV, VGAGRAY.DRV reads the [DISPLAY] section of the WIN.INI file and substitutes the values listed for the default values. The [DISPLAY] section has the following form:
[DISPLAY]
Gray0 = 0 ; 0
Gray1 = 31 ; 1F
Gray2 = 47 ; 2F
Gray3 = 63 ; 3F
Gray4 = 79 ; 4F
Gray5 = 95 ; 5F
Gray6 = 111 ; 6F
Gray7 = 127 ; 7F
Gray8 = 143 ; 8F
Gray9 = 159 ; 9F
GrayA = 175 ; AF
GrayB = 191 ; BF
GrayC = 207 ; CF
GrayD = 223 ; DF
GrayE = 239 ; EF
GrayF = 255 ; FF The characters 0 through F appended to the Gray keyword is the index to the gray-scale value. The integer is the gray-scale value. The gray-scale value can range from 0 through 255. Values listed represent the internal gray-scale values VGAGRAY.DRV uses by default. You must add the [DISPLAY] section to the WIN.INI file only if you want VGAGRAY.DRV to use other gray-scale values.