Manipulating sub-pictures of a compressed video signal

Abstract

The invention relates to manipulation of sub-pictures ( 303 ) in a picture such as a mosaic screen ( 301 ). An apparatus comprises a sub-picture generator ( 105 ) connected to a mosaic screen generator ( 107 ), which generates the mosaic screen ( 301 ) from the sub-pictures. The mosaic screen ( 301 ) is by a video compressor ( 111 ) divided into uncompressed picture blocks such that each block only comprise video data from one sub-picture. The picture blocks are compressed using a block compression scheme such as MPEG-2. The apparatus further comprises a video manipulation processor ( 113 ), which manipulates the sub-pictures by manipulating the association between control data in the video signal and the compressed picture blocks. The video data of the compressed picture blocks are not affected whereby de-compression and new compression is avoided.

What is claimed is: 
     
         1 - 17 . (canceled) 
     
     
         18 . An apparatus for video processing, the apparatus comprising:
 a processor; and   a memory storing instructions which, when executed, cause the processor to:
 divide a video signal into a plurality of sub-pictures, wherein each sub-picture of the plurality of sub-pictures is related to control data; 
 generate a compressed picture block from the plurality of sub-pictures, wherein the compressed picture block is associated with the control data related to the plurality of sub-pictures; and 
 manipulate a first sub-picture of the plurality of sub-pictures by manipulating an association between control data related to the first sub-picture and the compressed picture block, wherein the control data related to the first sub-picture is unchanged. 
   
     
     
         19 . The apparatus of  claim 18 , wherein manipulating the first sub-picture comprises replacing the compressed picture block with a different compressed picture block without changing the control data. 
     
     
         20 . The apparatus of  claim 18 , wherein manipulating the first sub-picture comprises associating the control data related to a second sub-picture with the compressed picture blocks associated with the control data related to the first sub-picture. 
     
     
         21 . The apparatus of  claim 18 , wherein the control data comprises information related to the position of an associated sub-picture. 
     
     
         22 . The apparatus of  claim 18 , wherein, when executed, the instructions cause the processor to select compressed data blocks of the first sub-picture by parsing a compressed video signal to detect identification data corresponding to the first sub-picture, the control data comprising the identification data. 
     
     
         23 . The apparatus of  claim 18 , wherein a compressed video signal comprises a plurality of slices each slice comprising a slice header and a number of consecutive compressed picture blocks. 
     
     
         24 . The apparatus of  claim 23 , wherein each slice comprises a single compressed picture block. 
     
     
         25 . The apparatus of  claim 23 , wherein each slice comprises a number of compressed picture blocks corresponding to a width of a sub-picture. 
     
     
         26 . The apparatus of  claim 23 , wherein the slice header comprises a slice number and the manipulation of the first sub-picture comprises manipulating the vertical position of the first sub-picture by modifying slice numbers for slices comprising compressed picture blocks of the first sub-picture. 
     
     
         27 . The apparatus of  claim 18 , wherein manipulating the first sub-picture comprises replacing compressed picture blocks with pre-defined compressed picture blocks without modifying the control data, wherein the pre-determined sub-pictures are inserted in a compressed video signal. 
     
     
         28 . A method for video processing, wherein the method operates within a processor and comprises:
 dividing a video signal into a plurality of sub-pictures, wherein each sub-picture of the plurality of sub-pictures is related to control data;   generating a compressed picture block from the plurality of sub-pictures, wherein the compressed picture block is associated with the control data related to the plurality of sub-pictures; and   manipulating a first sub-picture of the plurality of sub-pictures by manipulating an association between control data related to the first sub-picture and the compressed picture block, wherein the control data related to the first sub-picture is unchanged.   
     
     
         29 . The method of  claim 28 , wherein manipulating the first sub-picture comprises replacing the compressed picture block with a different compressed picture block without changing the control data. 
     
     
         30 . The method of  claim 28 , wherein manipulating the first sub-picture comprises associating the control data related to a second sub-picture with the compressed picture blocks associated with the control data related to the first sub-picture. 
     
     
         31 . The method of  claim 28 , wherein the control data comprises information related to the position of an associated sub-picture. 
     
     
         32 . The method of  claim 28 , wherein the method comprises selecting compressed data blocks of the first sub-picture by parsing a compressed video signal to detect identification data corresponding to the first sub-picture, the control data comprising the identification data. 
     
     
         33 . The method of  claim 28 , wherein a compressed video signal comprises a plurality of slices each slice comprising a slice header and a number of consecutive compressed picture blocks. 
     
     
         34 . The method of  claim 33 , wherein each slice comprises a single compressed picture block. 
     
     
         35 . The method of  claim 33 , wherein each slice comprises a number of compressed picture blocks corresponding to a width of a sub-picture. 
     
     
         36 . The method of  claim 33 , wherein the slice header comprises a slice number and manipulating the first sub-picture comprises manipulating the vertical position of the first sub-picture by modifying slice numbers for slices comprising compressed picture blocks of the first sub-picture. 
     
     
         37 . The method of  claim 28 , wherein manipulating the first sub-picture comprises replacing compressed picture blocks with pre-defined compressed picture blocks without modifying the control data, wherein the pre-determined sub-pictures are inserted in a compressed video signal.