Recording medium, recording method and apparatus, reproducing method and apparatus, data transmitting method, and data decrypting method

Abstract

A recording medium having an area in which data that has been encoded with a first error correction code is recorded, wherein data that can be decoded with a second error correction code that is different from the first error correction code is recorded to the area along with the data that has been encoded with the first error correction code, and wherein the data that can be decoded with the second error correction code composes at least part of encryption key data.

1 - 59 . (canceled)  
     
     
         60 : A data transmitting method, comprising the step of: 
 outputting data that has been encoded with a first error correction code along with data that composes a part of encryption key data that can be decoded with the first error correction code and that can be also decoded with a second error correction code that is different from the first error correction code.    
     
     
         61 : The data transmitting method as set forth in  claim 60 , 
 wherein the outputting step is performed by outputting the data that has been encoded with the first error correction code along with a plurality of pieces of data that can be decoded with the second error correction code so that when the data is decoded with the second error correction code, a predetermined error pattern is obtained.    
     
     
         62 : The data transmitting method as set forth in  claim 61 , 
 wherein the outputting step is performed by generating the encryption key data with a generation function having a factor of data that can be decoded with the second error correction code and outputting a pattern represented by the generated encryption key data.    
     
     
         63 : The data transmitting method as set forth in  claim 62 , 
 wherein whenever the data is output, the generation function is changed.    
     
     
         64 : The data transmitting method as set forth in  claim 61 , 
 wherein whenever the data is output, the recording pattern of the plurality of pieces of the data is changed.    
     
     
         65 : The data transmitting method as set forth in  claim 60 , 
 wherein part of the data that can be decoded with the second error correction code is dummy data.    
     
     
         66 : The data transmitting method as set forth in  claim 60 , 
 wherein the first error correction code and the second error correction code are used to encode at least two encoding sequences in respective directions, the first error correction code and the second error correction being different only in the encoding sequences, the data that can be decoded being data of which predetermined data is repeated as one unit of one of the two encoding sequences in the respective directions.    
     
     
         67 : The data transmitting method as set forth in  claim 60 , 
 wherein the first error correction code and the second error correction code are a code with which a C1 sequence in a vertical direction is encoded and a code with which a C2 sequence in a diagonal direction is encoded, respectively, the first error correction code and the second error correction code being different in their interleave lengths, the data that can be decoded being predetermined data repeated as one unit of the C1 sequence.    
     
     
         68 - 75 . (canceled)