Video for Windows 1.1 adds extended decompression capabilities. These messages let drivers decompress a frame of data directly to the screen, decompress to upside-down DIB, or decompress images described with source and destination rectangles. The following messages are used to obtain these capabilities:
| Message | Description |
|---|---|
| ICM_DECOMPRESSEX | Decompresses a frame of data into a buffer provided by the client-application. |
| ICM_DECOMPRESSEX_BEGIN | Prepare a driver for decompressing data. |
| ICM_DECOMPRESSEX_END | Cleans up after decompressing. |
| ICM_DECOMPRESSEX_QUERY | Determines if a driver can decompress a specific input format. |
These messages serve the same purpose as the ICM_DECOMPRESS messages except they use the ICDECOMPRESSEX structure. This structure contains the image input format and data, the output format and data, the source rectangle, and the destination rectangle.