Device for and a method of processing a data stream

Abstract

A device ( 2300 ) for processing a data stream ( 1800 ), wherein the device ( 2300 ) comprises a splitting unit ( 2305 ) for splitting adjacent frames ( 1902 ) of a partially decrypted data stream ( 1900 ), the partially decrypted data stream ( 1900 ) comprising decrypted frame boundary portions ( 1901 ) between adjacent frames ( 1902 ), at the frame boundary portions ( 1901 ), a replication unit ( 2306 ) for replicating split frames ( 1902 ) a number of times in accordance with a predetermined replication rate and a connecting unit ( 2307 ) for connecting the replicated split frames ( 1902 ).

1 .- 24 . (canceled) 
     
     
         25 . A data stream processing device ( 2300 ) comprising:
 a splitting unit ( 2305 ) for separating a partially decrypted data stream ( 1900 ), the partially decrypted data stream ( 1900 ) comprising decrypted frame boundary portions ( 1901 ) between adjacent encrypted frames ( 1902 ), each decrypted frame boundary portion ( 1901 ) comprising a picture start code portion ( 1903 ), into stream portions ( 2000 ) each including a respective decrypted frame boundary portion ( 1901 ) and a corresponding encrypted frame ( 1902 );   a replication unit ( 2306 ) for replicating said stream portions ( 2000 ) a number of times in accordance with a predetermined replication rate; and   a connecting unit ( 2307 ) for connecting the replicated stream portions ( 2000 ).   
     
     
         26 . The data stream processing device ( 2300 ) according to  claim 25 , further comprising a decryption unit ( 2304 ) for selectively replacing encrypted frame boundary portions between adjacent encrypted frames ( 1902 ) of an encrypted data stream ( 1800 ) by the decrypted frame boundary portions ( 1901 ), so as to form the partially decrypted data stream ( 1900 ). 
     
     
         27 . The data stream processing device ( 2300 ) according to  claim 26 , wherein the decryption unit ( 2304 ) is adapted for selectively replacing only the encrypted frame boundary portions between adjacent encrypted frames ( 1902 ) of the encrypted data stream ( 1800 ) by the decrypted frame boundary portions ( 1901 ), and for maintaining the encrypted frames ( 1902 ) encrypted. 
     
     
         28 . The data stream processing device ( 2300 ) according to  claim 26 , wherein the decryption unit ( 2304 ) is adapted for selectively replacing the encrypted frame boundary portions by the decrypted frame boundary portions ( 1901 ) so as to form the partially decrypted data stream ( 1900 ) as a basis for generating a trick-play stream ( 2201 ) with a reduced or minimum amount of decrypted portions. 
     
     
         29 . The data stream processing device ( 2300 ) according to  claim 25 , wherein the splitting unit ( 2306 ) is adapted for inserting a plaintext packet ( 1901 ) at the beginning of each encrypted frame ( 1902 ). 
     
     
         30 . The data stream processing device ( 2300 ) according to  claim 29 , wherein the plaintext packet ( 1901 ) comprises a header and/or an Adaptation Field. 
     
     
         31 . The data stream processing device ( 2300 ) according to  claim 25 , wherein the connecting unit ( 2307 ) is adapted for connecting the replicated stream portions ( 2000 ) based on identifying positions at which a frame boundary portion ( 1901 ) is spanning across two encrypted frames ( 1902 ) and based on correcting the identified positions. 
     
     
         32 . The data stream processing device ( 2300 ) according to  claim 25 , wherein the connecting unit ( 2307 ) is adapted for determining a size of at least a part of the frame boundary portions ( 1901 ) and for connecting the stream portions ( 2000 ) based on the determined size. 
     
     
         33 . The data stream processing device ( 2300 ) according to  claim 32 , wherein the connecting unit ( 2307 ) is adapted for decreasing the size of at least a part of the frame boundary portions ( 1901 ) in case that the determined size exceeds a predetermined threshold value. 
     
     
         34 . The data stream processing device ( 2300 ) according to  claim 32 , wherein the connecting unit ( 2307 ) is adapted for increasing the size of at least a part of the frame boundary portions ( 1901 ) in case that the determined size is below a predetermined threshold value. 
     
     
         35 . The data stream processing device ( 2300 ) according to  claim 34 , wherein the connecting unit ( 2307 ) is adapted to increase the size of at least a part of the frame boundary portions ( 1901 ) by inserting an extra portion into the data stream. 
     
     
         36 . The data stream processing device ( 2300 ) according to  claim 25 , further comprising a generation unit ( 2302 ) for processing the data stream for reproduction in a trick-play reproduction mode. 
     
     
         37 . A data stream processing method comprising:
 separating a partially decrypted data stream ( 1900 ), the partially decrypted data stream ( 1900 ) comprising decrypted frame boundary portions ( 1901 ) between adjacent encrypted frames ( 1902 ), each decrypted frame boundary portion ( 1901 ) comprising a picture start code portion ( 1903 ), into stream portions ( 2000 ) each including a respective decrypted frame boundary portion ( 1901 ) and a corresponding encrypted frame ( 1902 );   replicating said stream portions ( 2000 ) a number of times in accordance with a predetermined replication rate; and   connecting the replicated stream portions ( 2000 ).   
     
     
         39 . A non-transitory computer-readable medium, in which a computer program of processing a data stream, is stored, which computer program, when being executed by a processor ( 2302 ), is adapted to control or carry out the data stream processing method of claim  38 .