Method and apparatus for selecting compression for an incoming video signal in an interactive television system

Abstract

A method and apparatus for applying a variable compression factor to an incoming video stream in an STB. An increased amount of video may be stored within a PVR or disk on a STB by reducing the data storage requirements of incoming video based on available storage space and the type and size of the incoming video bit stream. Included are real time compression, or reduction in storage space requirements, by various data reduction methodologies including removing bits from the incoming video stream to reduce the amount of storage required to store the video stream. A background data reduction or compression technique is also provided wherein the incoming video stream is stored and data is reduced or further compressed at a later time to reduce data storage requirements.

What is claimed is  
     
         1 . A method of adaptive data compression in a distributed data processing system, comprising: 
 receiving an indication to store a digital data stream at a client device;    determining a variable data reduction factor corresponding to the data stream; and    storing the data stream.    
     
     
         2 . The method of  claim 1 , further comprising determining data storage requirement for said data stream based upon said reduction factor; and 
 wherein said storing is in response to detecting said client device has sufficient space to meet said data storage requirements.    
     
     
         3 . The method of  claim 2 , wherein said data stream is received as a compressed data stream, and wherein said method comprises further compressing the received data stream using said reduction factor prior to said storing.  
     
     
         4 . The method of  claim 2 , wherein said data stream is received and stored on a mass storage device as a data stream with a first level of compression, and wherein said method further comprises: 
 retrieving the stored data stream from the storage device;    further compressing the retrieved data stream; and    storing the further compressed data stream on the storage device.    
     
     
         5 . The method of  claim 4 , wherein said retrieved data is further compressed by removing high frequency block characteristics.  
     
     
         6 . The method of  claim 5 , wherein said retrieved data stream is not decompressed prior to said further compressing.  
     
     
         7 . The method of  claim 1 , further comprising: 
 determining a data storage requirement for said data stream based upon said reduction factor; and    determining the data reduction factor by dividing the incoming data storage requirements by the target storage, in response to detecting the data storage requirement does not exceed target storage.    
     
     
         8 . The method of  claim 7 , further comprising determining the data reduction factor by dividing the incoming data storage requirements by the available storage, in response to detecting the data storage requirement does not exceed available storage.  
     
     
         9 . The method of  claim 8 , further comprising retrieving and compressing a previously stored data stream using a variable data reduction factor in order to reduce the storage space required for the previously stored data stream by the amount of additional space needed to store the incoming data stream, in response to detecting the data storage requirement exceeds both the target storage and the available storage.  
     
     
         10 . The method of  claim 9 , wherein the stored data stream is selected based at least in part on one of program type and age.  
     
     
         11 . The method of  claim 1 , wherein the variable data reduction factor is transmitted to a server for use in compressing the data stream at the server prior to transmission to the client device.  
     
     
         12 . The method of  claim 2 , wherein said system comprises a television system, and wherein said data storage requirement is based in part on data received in an electronic programming guide.  
     
     
         13 . A client device for use in a distributed data processing system, said device comprising: 
 a receiver for receiving a digital data stream;    a storage device configured to store data; and    a processing unit configured to: 
 determine a variable data reduction factor corresponding to the data stream; and  
 store the data stream on the storage device.  
   
     
     
         14 . The device of  claim 13 , wherein said processing unit is configured to: 
 determine data storage requirements for said data stream based upon said reduction factor; and    store said data stream in response to detecting said storage device has sufficient space to meet said data storage requirements.    
     
     
         15 . The device of  claim 14 , wherein said data stream is received as a compressed data stream, and wherein said processing unit is configured to further compress the received data stream using said reduction factor prior to said storing.  
     
     
         16 . The device of  claim 14 , wherein said data stream is received and stored on said storage device as a data stream with a first level of compression, and wherein said processing unit is further configured to: 
 retrieve the stored data stream from the storage device;    further compress the retrieved data stream; and    store the further compressed data stream on the storage device.    
     
     
         17 . The device of  claim 16 , wherein said processing unit is configured to further compress said retrieved data by removing high frequency block characteristics.  
     
     
         18 . The device of  claim 13 , wherein said processing unit is configured to: 
 determine a data storage requirement for said data stream based upon said reduction factor; and    determine the data reduction factor by dividing the incoming data storage requirements by the target storage, in response to detecting the data storage requirement does not exceed target storage.    
     
     
         19 . The device of  claim 18 , wherein said processing unit is configured to determine the data reduction factor by dividing the incoming data storage requirements by the available storage, in response to detecting the data storage requirement does not exceed available storage.  
     
     
         20 . The device of  claim 19 , wherein said processing unit is configured to retrieve and compress a previously stored data stream using a variable data reduction factor in order to reduce the storage space required for the previously stored data stream by the amount of additional space needed to store the incoming data stream, in response to detecting the data storage requirement exceeds both the target storage and the available storage.  
     
     
         21 . The device of  claim 20 , wherein the stored data stream is selected based at least in part on one of program type and age.  
     
     
         22 . The device of  claim 13 , wherein the variable data reduction factor is transmitted to a remote server for use in compressing the data stream at the server prior to transmission to the client device.  
     
     
         23 . The device of  claim 14 , wherein said system comprises a television system, and wherein said data storage requirement is based in part on data received in an electronic programming guide.  
     
     
         24 . A computer readable medium containing computer executable instructions, wherein said instructions are executable to: 
 receive an indication to store a digital data stream at a client device;    determine a variable data reduction factor corresponding to the data stream; and    store the data stream.    
     
     
         25 . The medium of  claim 24 , wherein said instructions are executable to determine data storage requirements for said data stream based upon said reduction factor; and store said data stream in response to detecting said client device has sufficient space to meet said data storage requirements.  
     
     
         26 . The medium of  claim 25 , wherein said data stream is received as a compressed data stream, and wherein said instructions are executable to further compress the received data stream using said reduction factor prior to said storing.  
     
     
         27 . The medium of  claim 25 , wherein said data stream is received and stored on a mass storage device as a data stream with a first level of compression, and wherein said instructions are executable to: 
 retrieve the stored data stream from the storage device;    further compress the retrieved data stream; and    store the further compressed data stream on the storage device.    
     
     
         28 . The medium of  claim 27 , wherein said instructions are executable to further compress the retrieved data by removing high frequency block characteristics.  
     
     
         29 . The medium of  claim 24 , wherein said instructions are executable to: 
 determine a data storage requirement for said data stream based upon said reduction factor; and    determine the data reduction factor by dividing the incoming data storage requirements by the target storage, in response to detecting the data storage requirement does not exceed target storage.    
     
     
         30 . The medium of  claim 29 , wherein said instructions are executable to determine the data reduction factor by dividing the incoming data storage requirements by the available storage, in response to detecting the data storage requirement does not exceed available storage.  
     
     
         31 . The medium of  claim 29 , wherein said instructions are executable to retrieve and compress a previously stored data stream using a variable data reduction factor in order to reduce the storage space required for the previously stored data stream by the amount of additional space needed to store the incoming data stream, in response to detecting the data storage requirement exceeds both the target storage and the available storage.  
     
     
         32 . The medium of  claim 24 , wherein said instructions are executable to transmit the variable data reduction factor to a remote server for use in compressing the data stream at the server prior to transmission to the client device.