ID Number: Q64520
3.00 3.10
WINDOWS
Summary:
The format of a display bitmap determines the procedure that an
application uses to print it. The two display bitmap formats available
under Windows are device-dependent bitmaps (DDBs) and device-
independent bitmaps (DIBs). DIBs and DIB functions should be used to
print color bitmaps.
An application can use the BitBlt or StretchBlt function to print or
display a monochrome bitmap. Both printer drivers and display drivers
can process monochrome DDBs. However, an application must account for
the difference in resolution between a typical display and a typical
laser printer. The StretchBlt function enables an application to
appropriately change the size of a monochrome bitmap.
When the display bitmap is a color DDB, printing is more difficult
because the display DDB format may not match the printer DDB format.
Because Windows supports a wide variety of devices, this situation is
quite common. When the formats DDB differ, the application must
convert the display DDB into a print DDB or a DIB.
DIBs are designed to ease the process of transferring images between
devices. When an application uses a DIB, GDI or the output driver
performs any conversions required for the device. The SHOWDIB sample
application, provided in versions 3.0 and 3.1 of the Microsoft Windows
Software Development Kit (SDK), demonstrates converting a DDB to a DIB
and other common manipulations. The file DIB.C is of particular
interest. It contains the functions that perform the manipulations.
This code can be incorporated into other applications. Version 3.1 of
the Windows SDK also includes the DIBVIEW application, which
demonstrates similar techniques.
Additional reference words: 3.00 3.10