Abstract: A user mode device driver interface (UMDDI) is disclosed. The UMDDI is preferably implemented in Windows® NT® version 5.0 and similar systems. The UMDDI allows a device driver to execute in user-mode while the graphics engine (GRE) remains in kernel-mode. The UMDDI exists as a layer between the user-mode driver and GRE; from the perspective of GRE, it encapsulates the user-mode driver and makes it appear to be a normal kernel-mode driver. The UMDDI layer handles the kernel-to-user and user-to-kernel transitions, parameter validation, and management of the kernel-mode and user-mode data and objects.

Abstract: The present invention is directed to a method and system for automatic calibration of an acoustic system. The acoustic system may include a source A/V device, calibration computing device, and multiple rendering devices. The calibration system may include a calibration component attached to each rendering device and a source calibration module. The calibration component on each rendering device includes a microphone. The source calibration module includes distance and optional angle calculation tools for automatically determining a distance between the rendering device and a specified reference point upon return of the test signal from the calibration component.

Abstract: A user mode device driver interface (UMDDI) is disclosed. The UMDDI is preferably implemented in Windows® NT® version 5.0 and similar systems. The UMDDI allows a device driver to execute in user-mode while the graphics engine (GRE) remains in kernel-mode. The UMDDI exists as a layer between the user-mode driver and GRE; from the perspective of GRE, it encapsulates the user-mode driver and makes it appear to be a normal kernel-mode driver. The UMDDI layer handles the kernel-to-user and user-to-kernel transitions, parameter validation, and management of the kernel-mode and user-mode data and objects.

Abstract: A user mode device driver interface (UMDDI) is disclosed. The UMDDI is preferably implemented in Windows® NT® version 5.0 and similar systems. The UMDDI allows a device driver to execute in user-mode while the graphics engine (GRE) remains in kernel-mode. The UMDDI exists as a layer between the user-mode driver and GRE; from the perspective of GRE, it encapsulates the user-mode driver and makes it appear to be a normal kernel-mode driver. The UMDDI layer handles the kernel-to-user and user-to-kernel transitions, parameter validation, and management of the kernel-mode and user-mode data and objects.

Abstract: A user mode device driver interface (UMDDI) is disclosed. The UMDDI is preferably implemented in Windows® NT® version 5.0 and similar systems. The UMDDI allows a device driver to execute in user-mode while the graphics engine (GRE) remains in kernel-mode. The UMDDI exists as a layer between the user-mode driver and GRE; from the perspective of GRE, it encapsulates the user-mode driver and makes it appear to be a normal kernel-mode driver. The UMDDI layer handles the kernel-to-user and user-to-kernel transitions, parameter validation, and management of the kernel-mode and user-mode data and objects.

Abstract: A high speed and memory efficient system and method for rendering Bezier curves. The system utilizes a hybrid forward differencing function representing the Bezier curve defined by the Bezier control points and renders the curve with a small number of straight line segments. The system renders the curve in a manner that results in the same Bezier control points that are calculated using recursive subdivision techniques and rejects line segment approximations that would not be derived from recursive subdivision. The system can start at either end of a Bezier curve and will render the same approximation. The method is readily implemented on a computer and is applicable to Bezier curves of any order.

Abstract: A high speed and memory efficient method and system for determining with a computer when a curve defined by a set of Bezier, control points is sufficiently approximated by a line segment so that the reduction of the Bezier curve into smaller curves can stop. The method is readily implemented on a computer using vectors formed using vector addition and subtraction and is applicable to Bezier curves of any order.