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The color table for a device-independent bitmap (DIB) consists of 16-bit
indexes used as the colors for the bitmap. For the SetDIBitsToDevice
function, they are physical indexes; for the DeviceBitmapBits function, they
are logical indexes.
 
In the DeviceBitmapBits and SetDIBitsToDevice functions, the final
parameter, lpTranslate, provides information that is useful only for
palette-capable devices. However, all devices need to include this
parameter.
 
When DeviceBitmapBits is retrieving bits on a 256-color device, lpTranslate
is a pointer to a translation table with the following results.
 
Bitcount  Result
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1         A palette-sized array of bytes, each one either 0x00H or 0xFFH.
          The array is used to determine if the index in the bitmap
          corresponds to a zero or a 1 in the DIB.
 
4         A palette-sized array of bytes, each one containing a value
          between 0x00H and 0xFFH. Each index in the bitmap will map to the
          corresponding 4-bit values in the DIB.
 
8         lpTranslate will equal an identity table that can be ignored.
 
24        A palette-sized array of 32-bit values, each one containing the
          RGB value (and unused high byte) corresponding to the index in the
          bitmap.
 
On a palette-capable device when the source bitmap is a monochrome bitmap,
DeviceBitmapBits passes in a translation table that has only two entries,
instead of 256. Entry 0 has the color-table index for black and entry 1 has
the color table index for white.
 
When DeviceBitmapBits sets bitmap bits, GDI passes a pointer only if the
bitcount is 24. The parameter points to data maintained by GDI. For every
RGB value in the DIB, the display driver calls the DeviceColorMatch function
(GDI.449) to match an RGB value with an index. This function returns an
index to represent that color in the device-dependent bitmap.
 
 
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