Host CPU independent video processing unit

Abstract

The present invention relates to a video display processor comprised apparatus for receiving digital input signal components of a signal to be displayed, apparatus for converting the components to a desired format, apparatus for scaling and blending the signals in the desired format, apparatus for outputting the scaled and blended signals for display or further processing, and an arbiter and local timing apparatus for controlling the apparatus substantially independently of a host CPU.

We claim:  
     
       1. A video display processor comprising: 
       (a) means for receiving digital input signal components of a signal to be displayed;  
       (b) means for converting said components to a desired format,  
       (c) means for scaling and blending said signals components in said desired format,  
       (d) means for outputting said scaled and blended signals for display or further processing, and  
       (e) an arbiter and local timing means for operating and controlling all of said (a), (b), (c) and (d) means substantially independently of a host CPU.  
     
     
       2. A processor as defined in  claim 1  further including a video mixer for receiving said scaled and blended signals as processed source signals and for receiving destination data signals in said desired format, a multiplexer for multiplexing said source and data signals and for providing a multiplexed output signal therefrom for display or further processing. 
     
     
       3. A processor as defined in  claim 2  in which said receiving means is comprised of a line buffer for receiving said components from a video memory, in which said output signals are stored in an output buffer, and further comprising a control bus connected to the buffer, the converting means, the scaling and blending means, the video mixer and the multiplexer for carrying signals from the arbiter for controlling timing thereof. 
     
     
       4. A processor as defined in  claim 3  wherein said video memory further stores source signals and provides them as said input signal components, stores said destination signals, and stores and provides control signals for defining required operations of at least one of said scaling and blending means, components converting means and multiplexing means. 
     
     
       5. A processor as defined in  claim 4  including an address generating means for receiving said control signals and for generating address signals under further control of arbitration signals received from the arbiter for addressing and enabling timely operation of said converting means, scaling and blending means, video mixer and multiplexer via said control bus. 
     
     
       6. A method operating in a computer for combining a first image in a first format with a second image in a second format without requiring substantial involvement of a host central processing unit of the computer, the method comprising the steps of: 
       
         receiving said first image at a video display processor;  
       
       
         scaling and blending, by said video display processor, said first image to a desired size to produce a scaled image;  
       
       
         converting said scaled image, by said video display processor, to said second format to produce a converted image;  
       
       
         combining said converted image with said second image; and  
       
       
         providing control, by said video display processor, for said scaling and blending, said converting and said combining steps so that said converted image is combined with said second image without requiring substantial involvement of the host central processing unit of the computer. 
       
     
     
       7. The method of  claim 6 , wherein said combining step comprises: 
       
         multiplexing said converted image with said second image.