System software for use in a graphics computer system having a shared

Abstract

A computer system having a shared system memory, and system software in the computer system, are described herein. One or more user applications execute in the computer system. The computer system has a general purpose, shared system memory that is used for all processing, including video input/output operations and image conversion operations. The computer system also has a multimedia access and control module (MACM), which is the input/output interface between the computer system and the external world. In operation, the MACM receives, at one of its video input ports, video data comprising a video image (such as a frame or a field). The MACM stores the video image in a first buffer contained in a first buffer pool of the system memory. The first buffer pool was previously created by a user application. The user application previously associated the first buffer pool with the MACM's video input port. A video imaging and compression module (VICM) performs image conversion operations. Each user application creates one or more converter contexts of the VICM. Each converter context is capable of performing an image conversion operation. In operation, a converter context of the VICM performs an image conversion operation on the video image stored in the first buffer. Then, the converter context stores the results of the image conversion operation in a second buffer contained in a second buffer pool of the system memory. The second buffer pool is also associated with the user application.