Abstract: A digital video effects system for producing live-action video effects in real time includes an address generator having a pair of 2-D tables for providing x-coordinate and y-coordinate offset values. A third 2-D table contains warp activation factors (activators) which are scaled by a clip and gain processing technique to produce scaled activators. The scaled activators are used to scale the x- and y-offset values which are then combined with the original raster-order addresses to produce frame buffer readout addresses. An output video signal is produced by an inverse mapping of the input frame buffer to the output. The 2-D tables provide control of the image on a pixel-by-pixel basis. The degree of scaling by the clip and gain unit varies with time so that the resulting readout addresses also vary with time. A video effect, therefore, is produced simply by adjusting the scaling of the clip and gain unit. Moreover, a variety of effects can be achieved simply by changing the various 2-D tables.

Abstract: This invention employs an incremental technique for performing a perspective transformation on a planar television image. The equipment modifies the coefficients to a two by two matrix multiplier at the pixel or line rate. This allows for perspective generation along either the X or Y axis of the television screen. The invention will also provide perspective generation for rotation of the image about the Z axis in addition to the rotation about one of the X or Y axes.