The MCI_GETDEVCAPS_ITEM and MCI_GETDEVCAPS_MESSAGE flags are mutually exclusive. Only a single item or message can be specified.

MCI_DGV_GETDEVCAPS_MINIMUM_RATE, MCI_DGV_GETDEVCAPS_MAXIMUM_RATE, and MCI_DGV_GETDEVCAPS_MAX_WINDOWS are not supported. If these flags are specified, MCIERR_UNSUPPORTED_FLAG is returned.

MCI_DGV_GETDEVCAPS_VIDEO_X_EXTENT, MCI_DGV_GETDEVCAPS_VIDEO_Y_EXTENT, MCI_DGV_GETDEVCAPS_IMAGE_X_EXTENT, and MCI_DGV_GETDEVCAPS_IMAGE_Y_EXTENT return hardware-specific values from the vendor-specific driver (VSD). This is normally the size of the video capture card's frame buffer.

The values for video extent specify the largest video image that can be captured and thereby define the extents of the video capture coordinate system. Capture regions specified by MCI_PUT must lie entirely within these extents.

The values for image extent specify the largest still image that can be captured with the device. The values returned are the same as video extents for supported hardware.