Method and apparatus for processing digital service signals

Abstract

An apparatus for processing digital service signals includes a receiving module configured to receive contents having watermarks, where the watermarks are inserted in audio or video frames of the contents, the watermarks carry channel information related to the contents, and content information having URL information for additional data of the contents. An extracting module is configured to extract the watermarks from the audio or video frames, and an obtaining module is configured to obtain the additional data over an IP (Internet Protocol) network using the extracted watermarks.

1 - 20 . (canceled) 
     
     
         21 . A method of providing an interactive service related to a content, the method comprising:
 receiving the content having plural watermarks, wherein the watermarks are inserted in video frames of the content,   wherein at least one of the frames include a first-level watermark, wherein at least one of the frames including the first-level watermark further includes a second-level watermark as an extension for the first-level watermark,   wherein the first-level watermark includes major information for the interactive service of the content, and a first extension indicator, wherein the first extension indicator indicates whether the first-level watermark has extension,   wherein the second-level watermark includes minor information for the interactive service of the content;   extracting the first-level watermark to obtain the major information for the interactive service, and the first extension indicator;   deciding whether the minor information are needed for providing interactive service;   extracting the second-level watermark based on the first extension indicator to obtain the minor information for the interactive service;   providing the interactive service of the content by using the extracted information.   
     
     
         22 . The method of  claim 21 , wherein a period between frames having first level watermarks are different from a period between frames having both first-level watermarks and second-level watermarks. 
     
     
         23 . The method of  claim 21 , wherein the first-level watermark includes an identification information for source of the content. 
     
     
         24 . The method of  claim 21 , wherein the second-level watermark includes a timestamp, and
 wherein the timestamp establishes a time base for synchronizing the interactive service with the content.   
     
     
         25 . The method of  claim 21 , wherein the first-level watermark is inserted in a logo image area of the video frame, and
 wherein the second-level watermark is inserted in a symbol image area of the video frame.   
     
     
         26 . The method of  claim 23 , wherein at least one of the frames including the second-level watermark further includes a third-level watermark as an extension for the second-level watermark, and
 wherein the second-level watermark further includes a second extension indicator indicating whether the second-level watermark has extension.   
     
     
         27 . The method of  claim 26 , wherein the third-level watermark includes an URL information for additional data of the interactive service. 
     
     
         28 . The method of  claim 27 , wherein the method further includes, deciding whether the URL information for additional data are needed for providing interactive service;
 extracting the third-level watermark based on the second extension indicator to obtain the URL information for additional data;   obtaining the additional data over an IP (Internet Protocol) network by using the extracted URL information; and   providing the interactive service of the content by using the obtained additional data.   
     
     
         29 . A method of providing an interactive service related to a content, the method comprising:
 generating plural watermarks;   inserting the generated watermarks into video frames of the content,   wherein at least one of the frames include a first-level watermark, wherein at least one of the frames including the first-level watermark further includes a second-level watermark as an extension for the first-level watermark,   wherein the first-level watermark includes major information for the interactive service of the content, and a first extension indicator, wherein the first extension indicator indicates whether the first-level watermark has extension,   wherein the second-level watermark includes minor information for the interactive service of the content,   wherein the major information and the minor information for the interactive service are used to provide the interactive service of the content; and   transmitting the content having the watermarks.   
     
     
         30 . The method of  claim 29 , wherein a period between frames having first level watermarks are different from a period between frames having both first-level watermarks and second-level watermarks. 
     
     
         31 . The method of  claim 29 , wherein the first-level watermark includes an identification information for source of the content. 
     
     
         32 . The method of  claim 29 , wherein the second-level watermark includes a timestamp, and
 wherein the timestamp establishes a time base for synchronizing the interactive service with the content.   
     
     
         33 . The method of  claim 29 , wherein the first-level watermark is inserted in a logo image area of the video frame, and
 wherein the second-level watermark is inserted in a symbol image area of the video frame.   
     
     
         34 . The method of  claim 31 , wherein at least one of the frames including the second-level watermark further includes a third-level watermark as an extension for the second-level watermark, and
 wherein the second-level watermark further includes a second extension indicator indicating whether the second-level watermark has extension.   
     
     
         35 . The method of  claim 34 , wherein the third-level watermark includes an URL information for additional data of the interactive service. 
     
     
         36 . The method of  claim 35 , wherein the URL information for additional data is used for obtaining the additional data over an IP (Internet Protocol) network, and
 wherein the additional data is used for providing the interactive service of the content.