Method for managing recorded streams in a rewritable recording medium

Abstract

The present invention relates to a method for managing playlists of a rewritable recording medium in order to prevent unlimited playback or illegal edition of television broadcast programs or movies wherein copyright protection is required. The present invention operates by adding information needed for automatic timed deletion of consecutively recorded clips of A/V streams and deletion time information into the playlists of a recording medium such as a high density rewritable optical disc (BD-RW), whereby referring to the recorded information, the corresponding clips of A/V streams are automatically deleted.

1 . A method for processing digital content, comprising steps of:
 determining whether or not control information to restrict a length of time for an access to the digital content is present based on indication information; and   controlling access to the digital content based on the determining step,   wherein the indication information indicates whether the control information is present.   
   
   
       2 . The method of  claim 1 , wherein the control information includes time information indicating the length of time during which access to the digital content is allowed, the time information specifying one of:
 an absolute time, at which point access to the digital content will not be allowed, or   a relative time from a first access of the digital content, at which point further access to the digital content will not be allowed.   
   
   
       3 . The method of  claim 1 , wherein the step of controlling access to the digital content comprises:
 analyzing time information included in the control information, if the indication information indicates that the control information is present; and   determining whether the digital content may be accessed based on a result of the analyzing step.   
   
   
       4 . The method of  claim 3 , wherein the analyzing step comprises comparing the time information with a current time. 
   
   
       5 . The method of  claim 4 , wherein the determining step comprises accessing the digital content based on a result of the comparing step. 
   
   
       6 . The method of  claim 4 , wherein the determining step comprises deciding that the digital content can be accessed if a result of the comparing step indicates that there is time remaining in which access to the digital content is allowed. 
   
   
       7 . The method of  claim 4 , wherein the determining step comprises deciding that the digital content cannot be accessed if a result of the comparing step indicates that there is no time remaining in which access to the digital content is allowed. 
   
   
       8 . The method of  claim 7 , further comprising deleting the digital content if the result of the comparing step indicates that there is no time remaining in which access to the digital content is allowed. 
   
   
       9 . The method of  claim 1 , wherein the controlling step comprises permitting access to the digital content if the control information is not present. 
   
   
       10 . A method of managing a digital content, comprising steps of:
 checking whether time information to restrict a length of time for access to the digital content is present based on indication information, prior to accessing the digital content, wherein the time information is available only if the indication information specifies a restricted access to the digital content;   allowing access to the digital content if the time information is not present, or if the time information is present and access time remains; and   not allowing access to the digital content if the access time does not remain.   
   
   
       11 . The method of  claim 10 , wherein the time information specifies one of:
 an absolute time, at which point access to the digital content will not be allowed, or   a relative time from a first access of the digital content, at which point further access to the digital content will not be allowed.   
   
   
       12 . The method of  claim 10 , wherein the indication information is included in management information, the management information further including version information for identifying a version of the management information. 
   
   
       13 . A method of managing digital content, comprising steps of:
 determining whether indication information specifies a restricted access to the digital content;   comparing time information with the current time to determine whether the digital content can be accessed if the indication information specifies the restricted access to the digital content as a result of the determining step;   allowing access to the digital content if the indication information does not specify the restricted access, or if the time information indicates that an access time remains; and   not allowing access to the digital content if the access time does not remain,   wherein the time information indicates the access time, and   wherein the time information is present if the indication information specifies the restricted access to the digital content.   
   
   
       14 . The method of  claim 13 , wherein the indication information specifies the restricted access including the access time. 
   
   
       15 . The method of  claim 13 , wherein the time information specifies one of:
 an absolute time, at which point access to the digital content will not be allowed, or   a relative time from a first access of the digital content, at which point further access to the digital content will not be allowed.   
   
   
       16 . The method of  claim 13 , wherein the indication information is included in management information, the management information further including version information for indicating a version of the management information. 
   
   
       17 . The method according to  claim 2 , wherein the first access to the digital content is a first playback of the digital content. 
   
   
       18 . The method according to  claim 11 , wherein the first access to the digital content is a first playback of the digital content. 
   
   
       19 . The method according to  claim 15 , wherein the first access to the digital content is a first playback of the digital content.