Browse Prior Art Database

Method Allowing Unlimited Users of a Video Hardware Assist Capability

IP.com Disclosure Number: IPCOM000117517D
Original Publication Date: 1996-Mar-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 55K

Publishing Venue

IBM

Related People

Flurry, GA: AUTHOR

Abstract

Disclosed is a method for permitting unlimited users of a hardware video scaling, color space conversion, and dithering engine. The method uses a specialized shared memory approach in conjunction with pacing of individual users of the engine.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 54% of the total text.

Method Allowing Unlimited Users of a Video Hardware Assist Capability

      Disclosed is a method for permitting unlimited users of a
hardware video scaling, color space conversion, and dithering engine.
The method uses a specialized shared memory approach in conjunction
with pacing of individual users of the engine.

      The embodiment of method described is a device driver that
allows an unlimited number of users to share a video engine, with
high performance for a small number of users and an acceptable level
of performance for unlimited users.  The memory associated with the
video engine, for storing images to be scaled, is partitioned into
blocks.  Some of the blocks are for "exclusive-use" of users
requiring high performance; once allocated to a particular user, an
exclusive-use block stays allocated to that user until the user is
finished with the video engine.  Other blocks are for "shared-use;" a
shared-use block can be temporarily allocated to a user only long
enough to display one image, then temporarily allocated to the next
user, and so on.

      Using the video engine via the device driver is a two step
process.  In the "image prepare" step for shared-use memory, this
method simply indicates, in an "image structure" created for the
image, that the image uses shared memory.  No memory blocks are
actually allocated for the image as would be done for exclusive-use
memory.

      In the "image display" step, the method locks the appropriate...