Method for assisting video compression in a computer system

Abstract

One embodiment of the present invention provides a method that facilitates compression of video data in a computer system by performing the time-consuming task of computing the difference between successive frames of video data independently from the central processing unit. This frees the often-overburdened central processing unit from performing this time-consuming compression operation and can thereby improve the handling of video data. Thus, one embodiment of the present invention can be characterized as a method thr compressing video data in a computer system. This method includes receiving a stream of data from a current video frame in the computer system. It also includes computing a difference frame from the current video frame and a previous video frame “on-the-fly” as the current video frame streams into the computer system. The method additionally includes storing the difference frame in a memory in the computer system.

1 . A method for compressing video data in a computer system comprising:
 computing a difference frame from a current video frame and a previous video frame as the current video frame streams into the computer system;   storing the difference frame in a system memory in the computer system; and   a processor retrieving the difference frame directly from the system memory via a core logic chip using a dedicated processor interface therebetween to complete compression of the video data.   
     
     
         2 . The method of  claim 1 , including storing the current video frame in the system memory in the computer system. 
     
     
         3 . The method of  claim 2 , wherein the current video frame is written over a previous video frame in the system memory. 
     
     
         4 . The method of  claim 1 , wherein computing the difference frame includes computing an exclusive-OR between the current video frame and the previous video frame. 
     
     
         5 . The method of  claim 1 , wherein computing the difference frame includes computing a difference between a block of data from the current video frame and a block of data from the previous video frame. 
     
     
         6 . The method of  claim 1 , wherein storing the difference frame in the system memory includes storing the difference frame in the system memory using block transfers. 
     
     
         7 . The method of  claim 1 , including compressing the video data using the difference frame to produce compressed video data. 
     
     
         8 . The method of  claim 1 , including performing a color space conversion on the video data. 
     
     
         9 . The method of  claim 1 , including using the video data in compressed form in a video teleconferencing system. 
     
     
         10 . The method of  claim 1 , including storing instructions and data for the computer system in the system memory. 
     
     
         11 . The method of  claim 1 , wherein computing the difference frame includes computing the difference frame in a core logic chip within the computer system. 
     
     
         12 . The method of  claim 1 , wherein computing the difference frame includes computing the difference frame in circuitry outside of the processor in the computer system. 
     
     
         13 . A method for compressing video data in a computer system, comprising:
 computing a difference frame from a current video frame and a previous video frame as the current video frame streams into the computer system, wherein computing the difference frame includes computing an exclusive-OR between the current video frame and the previous video frame;   storing the difference frame in a memory in the computer system;   storing the current video frame in the memory in the computer system;   a processor retrieving the difference frame directly from the system memory via a core logic chip compressing the video data using the difference frame to produce compressed video data.   
     
     
         14 . The method of  claim 13 , wherein the current video frame is written over a previous video frame in the memory. 
     
     
         15 . The method of  claim 13 , wherein computing the difference frame includes computing a difference between a block of data from the current video frame and a block of data from the previous video frame. 
     
     
         16 . The method of  claim 13 , wherein storing the difference frame in memory includes storing the difference frame in the memory using block transfers. 
     
     
         17 . The method of  claim 13 , including using the compressed data in a video teleconferencing system. 
     
     
         18 . The method of  claim 13 , including performing a color space conversion on the video data. 
     
     
         19 . The method of  claim 13 , including storing instructions and data for the computer system in the memory. 
     
     
         20 . The method of  claim 13 , wherein computing the difference frame includes computing the difference frame in the core logic chip within the computer system.