Methods of Performing Spatial Error Concealment For Digital Video

Abstract

Error concealment is used to hide the effects of errors detected within digital video information. A novel spatial error concealment technique is disclosed for use when the error concealment mode decision determines that spatial error concealment should be used for reconstruction. The novel spatial error concealment technique divides a corrupt macroblock into multiple regions, such as, a corner region, a row adjacent to the corner region, a column adjacent to the corner region, and a remainder main region. Those regions are then reconstructed and information from earlier reconstructed regions may be used in later reconstructed regions. Finally, a macroblock refreshment technique is disclosed for preventing error propagation from harming non-corrupt inter-blocks. Specifically, an inter-macroblock may be ‘refreshed’ using spatial error concealment if there has been significant error caused damage that may cause the inter-block to propagate the errors.

We claim: 
     
         1 . A method of refreshing macroblocks when performing error concealment, said method comprising the steps of:
 determining if a macroblock should be refreshed by
 determining if said macroblock is not corrupt; 
 determining if said macroblock is an inter-macroblock; 
 determining if a damage factor has exceeded a threshold; and 
   refreshing said macroblock if said macroblock needs to be refreshed by using spatial error concealment on said macroblock.   
     
     
         2 . The method of refreshing macroblocks as set forth in  claim 1  wherein said refreshing is only performed in a chrominance domain. 
     
     
         3 . The method of refreshing macroblocks as set forth in  claim 1  wherein said damage factor is increased by a number of corrupt macroblocks. 
     
     
         4 . The method of refreshing macroblocks as set forth in  claim 1  wherein said damage factor is increased by an amount of motion. 
     
     
         5 . The method of refreshing macroblocks as set forth in  claim 1  wherein said damage factor is decreased by an amount of intra-macroblocks. 
     
     
         6 . The method of refreshing macroblocks as set forth in  claim 1  wherein said damage factor is increased when a scene-change is detected. 
     
     
         7 . A computer readable medium, said computer readable medium comprising set of instructions for refreshing macroblocks when performing error concealment, said instructions implementing the steps of:
 determining if a macroblock should be refreshed by
 determining if said macroblock is not corrupt; 
 determining if said macroblock is an inter-macroblock; 
 determining if a damage factor has exceeded a threshold; and 
   refreshing said macroblock if said macroblock needs to be refreshed by using spatial error concealment on said macroblock.   
     
     
         8 . The computer readable medium as set forth in  claim 7  wherein said refreshing is only performed in a chrominance domain. 
     
     
         9 . The computer readable medium as set forth in  claim 7  wherein said damage factor is increased by a number of corrupt macroblocks. 
     
     
         10 . The computer readable medium as set forth in  claim 7  wherein said damage factor is increased by an amount of motion. 
     
     
         11 . The computer readable medium as set forth in  claim 7  wherein said damage factor is decreased by an amount of intra-macroblocks. 
     
     
         12 . The computer readable medium as set forth in  claim 7  wherein said damage factor is increased when a scene-change is detected.