Creating an EnDIVE Multimedia Extension GRADD

OS/2 Warp supports an enhanced direct interface video extension, referred 
to as EnDIVE. This extension is designed to support graphics chips that 
handle video acceleration in hardware. The EnDIVE multimedia extension 
described here supports the same level of functionality under the GRADD 
Model. 

The following figure diagrams the DIVE Display Engine. 

The phrase "video acceleration" recently has taken on a new meaning. In 
the past, video acceleration was a way of describing hardware assist for 
bitblts, lines, and so on. Today, video acceleration or video accelerators 
describe hardware assist for video-acceleration software. The minimum 
requirement necessary to be considered a video accelerator is the ability 
to perform a stretch blit in hardware. More powerful video accelerators 
perform additional functions, such as dynamic color conversion, 
decompression, and compression. These types of operations are directly 
applicable to the needs of multimedia video-acceleration software. 

The EnDIVE multimedia extension GRADD consists of four functions, 
contained in the ulXSubFunction field of the HWEXTENSION packet. For each 
extension function, the input packet is pointed to by the pXP1 field of 
the HWEXTENSION packet. 

The four EnDIVE functions are listed below: 

   *  EXT_CMD_ENDIVE_GET 

   *  EXT_CMD_ENDIVE_INIT 

   *  EXT_CMD_ENDIVE_PUT 

   *  EXT_CMD_ENDIVE_QUERY 
 

 For details on each of these functions, refer to Enhanced Direct 
 Interface Video Extension (EnDIVE) Functions.