Copy prevention method and apparatus of a digital recording/reproducing system

Abstract

A copy prevention method and apparatus of a digital magnetic recording/reproducing system performs the copy prevention function by encoding to insert a marker involving copy prevention function information and executing the function and allows a program supplier to realize a desired copy prevention function of various patterns, in which the marker formed by a control word for scrambling audio and video bit straps and copy prevention information for preventing an illegal copy is encrypted by an encoded key to be multiplexed with the audio and video bit strips scrambled by the control word. The marker transmitted is detected from the bit strips to be decrypted and analyzed by the encoded key to determine whether the copy is permitted or not, so that the detected marker is updated to be recorded on a video tape and the control word is produced from the marker to perform the descrambling to supply the result to a monitor to be displayed. Thus, the program supplier selects the copy prevention function, and a separate format converting apparatus is not required since a field defined within a GA format is utilized while an existing DVCR is not need to be changed for performing the copy prevention function as the data amount to be recorded is not increased.A method and apparatus for transmitting digital data are discussed. According to an embodiment, the invention is directed to a method of transmitting digital data using a data processing apparatus including a scrambler, the method comprising: scrambling, by the scrambler, one or more data units included in the digital data based on control data, the digital data including a first data block and one or more succeeding data blocks, each data block including a header and one data unit, at least the header in the first data block including the control data, wherein the first data block and the one or more succeeding data blocks are scrambled based on the control data included in the first data block; and transmitting, by the data processing apparatus, the one or more scrambled data units and the control data, the control data being used for controlling a parameter of a scrambling/descrambling operation.

What is claimed is: 
     
       1. A copy prevention method of a digital magnetic recording/reproducing system comprising:
 an audio and video signal transmitting process of encrypting a marker formed by a control word for scrambling audio and video bit strips and copy prevention information for preventing an illegal copy by means of an encoding key, and multiplexing said marker with said audio and video bit strips scrambled by said control word, and   an audio and video signal receiving/recording process of detecting said marker from said transmitted bit strips, decrypting and analyzing the detected marker by means of an encoded key to determine whether copy is permitted or not, updating said detected marker to be recorded on a video tape, and generating said control word from said marker to perform a descrambling and supply the audio and video signals to be displayed on a monitor.   
     
     
       2. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 1 , wherein said marker is placed on a transport-private-data field within said bit strips. 
     
     
       3. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 2 , wherein said marker is comprised of a copy prevention information area recorded with said copy prevention information for preventing said illegal copy, and a control word area recorded with said control word for descrambling. 
     
     
       4. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 3 , wherein said marker is formed of 8 bytes. 
     
     
       5. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 4 , wherein said copy prevention area is formed of one byte. 
     
     
       6. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 4 , wherein said control word area is formed of four bytes. 
     
     
       7. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 3 , wherein said copy prevention information is formatted by including a generational copy control field for restricting the number of permitting said copy of a program. 
     
     
       8. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 7 , wherein said generational copy control field comprises:
 an allowable generational field for restricting the copy number of said program; and   a current generational field representing a current generation of a duplicated program.   
     
     
       9. A copy prevention-method of a digital magnetic recording/reproducing system as claimed in  claim 1 , wherein said audio and video transmitting process comprises:
 an audio and video bit-strip encoding step of encoding said audio and video bit strips;   a control word generating step of generating said control word for scrambling;   a scrambling step for scrambling said encoded audio and video bit strips by means of said generated control word;   a copy prevention information generating step of generating said copy prevention information for preventing said illegal copy;   a marker generating and encrypting step of generating said marker by means of said generated control word and copy prevention information and encrypting said marker by means of said encoded key; and   a multiplexing and transmitting step of multiplexing to transmit said scrambled audio and video bit strips and encrypted marker.   
     
     
       10. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 1 , wherein said audio and video signal receiving/recording process comprises:
 a marker detecting step of demultiplexing said transmitted bit strips to detect said marker, and decrypting said marker by means of said encoded key;   a marker analyzing step of analyzing said detected marker to determine whether said copy is permitted or not, and detecting said control word;   an audio and video decoding step of descrambling and decoding said transmitted audio and video bit strips by means of said detected control word, and outputting said audio and video signals; and   a marker inserting step of updating said detected marker and encrypting said updated marker by means of said encoded key to insert the result when it is determined that said copy is permitted after analyzing said marker.   
     
     
       11. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 10 , wherein said marker analyzing step comprises:
 a copy prevention information detecting step of detecting said copy prevention information for preventing said illegal copy from said detected marker;   a copy number restricting step of comparing an allowable generation of said allowable generational field and a current generation of said current generational field representing said current generation for restricting the number of permitting said copy of said program within said detected copy prevention information, and determining whether said copy is permitted or not-to process the result; and   a control word detecting step of detecting said control word for descrambling from said detected marker.   
     
     
       12. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 11 , wherein said copy number restricting step comprises:
 comparing said allowable generation of said allowable generational field with said current generation of said current generational field to determine whether said allowable generation is below said current generation;   inhibiting said copy when it is determined that said allowable generation is below said current generation; and   permitting said copy when it is determined that said allowable generation is-not below said current generation, and proceeding to said marker inserting step.   
     
     
       13. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 12 , wherein said step of inhibiting said copy is performed by destructing said control word or impeding an output of said control word to block a reproduction after recording. 
     
     
       14. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 10 , wherein said control word is periodically changed. 
     
     
       15. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 14 , wherein said control word is changed in the interval of 0.6 second. 
     
     
       16. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 14 , wherein said marker is placed on said transport-private-data field within said bit strips whenever said control word is changed. 
     
     
       17. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 16 , wherein said marker inserting step comprises the steps of:
 updating said marker when the analysis of said marker determines to permit said copy;   encrypting said updated marker by means of said encoded key; and   replacably inserting said encrypted marker with a succeeding marker.   
     
     
       18. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 1 , wherein said encoded key is transported via a separate transmission line to be stored. 
     
     
       19. A copy prevention method of a digital magnetic recording/reproducing system as claimed in  claim 18 , wherein said encoded key is transported via said separate transmission line for a prescribed time interval. 
     
     
       20. A copy prevention apparatus of a digital magnetic recording/reproducing system comprising:
 an encrypted marker detecting and inserting part for detecting a marker from input bit strips, and inserting an updated marker to said bit strips to output the result;   a marker analyzing and processing part for decrypting and analyzing the encrypted marker from said marker detecting and inserting part by means of an encoded key, outputting a control word for descrambling said bit strips, and updating and encrypting the decrypted marker by means of said encoded key to output the result;   a buffer part for buffering said control word and updated and encrypted marker from said marker analyzing and processing part, and inserting said updated and encrypted marker in said marker detecting and inserting part; and   a descrambler for descrambling said bit strips provided via said marker detecting and inserting pant by means of said control word from said buffer part.   
     
     
       21. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 20 , wherein said encoded key is transported via a separate transmission line to be stored. 
     
     
       22. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 21 , wherein said encoded key is transported via said separate transmission line for a prescribed time interval. 
     
     
       23. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 20 , wherein said marker is placed on a transport-private-data field within said bit strips whenever said control word is changed. 
     
     
       24. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 23 , wherein said marker is comprised of a copy prevention information area recorded with said copy prevention information for preventing said illegal copy, and a control word area recorded with said control word for descrambling. 
     
     
       25. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 24 , wherein said marker is formed of 8 bytes. 
     
     
       26. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 25 , wherein said copy prevention area is formed of one byte. 
     
     
       27. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 25 , wherein said control word area is formed of four bytes. 
     
     
       28. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 24 , wherein said copy prevention information is formatted by including a generational copy control field for restricting the copy number of a program. 
     
     
       29. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 28 , wherein said generational copy control field comprises:
 an allowable generational field for restricting the number of permitting the copy of a program; and   a current generational field representing a current generation of a duplicated program.   
     
     
       30. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 20 , wherein said control word is periodically changed. 
     
     
       31. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 30 , wherein said control word is changed in the interval of 0.6 second. 
     
     
       32. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 30 , wherein said marker is placed on a transport-private-data field within said bit strips whenever said control word is changed. 
     
     
       33. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 30 , wherein said marker detecting and inserting part replacably inserts said updated marker with a succeeding marker. 
     
     
       34. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 20 , wherein said marker detecting and inserting part comprises:
 a marker detecting section for detecting to output said encrypted marker from said input bit strips to said marker analyzing and processing part, outputting a marker detection flag signal for informing of the position of said encrypted marker within said bit strips to said descrambler to be used as a reference signal of initializing said descrambler, and outputting said bit strips; and   a marker inserting section for inserting said updated and encrypted marker from said buffer part to said bit strips from said marker detecting section in accordance with said marker detection flag signal from said marker detecting section to output the result to said descrambler.   
     
     
       35. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 24 , wherein said marker analyzing and processing part comprises:
 a marker decoding section for decrypting said encrypted marker from said marker detecting and inserting part by means of said encoded key;   a marker analyzing section for analyzing said copy prevention information within said marker from said marker decoding section, and outputting said control word to said buffer part and a control signal for updating said marker when said copy is permitted; and   a marker updating and encoding section for updating said marker from said marker decoding section in accordance with said control signal from said marker analyzing section, and encrypting said updated marker by means of said encoded key to output the result to said buffer part.   
     
     
       36. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 35 , wherein said marker analyzing and processing part further comprises an encoded key storage section for storing said encoded key to output it to said marker analyzing section and marker updating and encoding section. 
     
     
       37. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 35 , wherein said marker analyzing section compares an allowable generation of an allowable generational field with a current generation of a current generational field representing a current generation of a duplicated program to determine whether said copy is permitted or not. 
     
     
       38. A copy prevention apparatus of a digital magnetic recording/reproducing system as claimed in  claim 20 , wherein said buffer part comprises:
 a marker buffer for temporally storing said updated and encrypted marker from said marker analyzing and processing part, and outputting the result to said marker detecting and inserting part; and   a control word buffer for temporally storing said control word from said marker analyzing and processing part, and outputting the result to said descrambler.   
     
     
       39. A method of transmitting digital data using a data processing apparatus including a scrambler, the method comprising:
 generating control data for initializing the scrambler;   initializing the scrambler based on the control data directly input into the scrambler;   scrambling, using the same initialized scrambler and the same control data, both digital audio data and digital video data;   generating a first 188 byte data block including a header with the control data used to initialize the scrambler and a scrambled data portion including the scrambled digital audio and/or digital video data;   generating at least a second 188 byte data block including the scrambled digital audio and digital video data and not including the control data;   determining if a minimum of a multiple of four 188 byte data blocks have been scrambled;   determining if a timing point that includes a decimal fraction of 0.66 control words per second (CW/s) has passed since a previous initialization of the scrambler;   re-initializing the scrambler based on a new control word when the determining steps determine either the minimum of the multiple of four 188 byte data blocks have been scrambled or the timing point that includes the decimal fraction of 0.66 control words per second (CW/s) has passed since the previous initialization of the scrambler; and   transmitting, by the data processing apparatus, the generated first data block and the at least second data block.    
     
     
       40. The method of claim 39, wherein the scrambling step does not scramble the header in the first 188 byte data block.  
     
     
       41. The method of claim 43, further comprising
 identifying the number of times the digital data has been copied and/or the number of times permitted to copy the digital data, based on copy prevention information included in the header of the first data block, wherein the copy prevention information includes at least one of current generation information and allowable generation information, the current generation information indicating the number of times the digital data has been copied and the allowable generation information indicating the number of times permitted to copy the digital data.    
     
     
       42. An apparatus for transmitting digital data, comprising:
 a processor; and   a memory connected to the processor and including executable instructions that when executed by the processor, cause the processor to perform:   generating control data for initializing the scrambler; initializing the scrambler based on the control data;   scrambling, using the same initialized scrambler and the same control data, both digital audio data and digital video data;   generating a first 188 byte data block including a header with the control data used to initialize the scrambler and a scrambled data portion including the scrambled digital audio and/or digital video data;   generating at least a second 188 byte data block including the scrambled digital audio and digital video data and not including the control data;   determining if a minimum of a multiple of four 188 byte data blocks have been scrambled;   determining if a timing point that includes a decimal fraction of 0.66 control words per second (CW/s) has passed since a previous initialization of the scrambler;   re-initializing the scrambler based on a new control word and based on the determination that either the minimum of the multiple of four 188 byte data blocks have been scrambled or the timing point that includes the decimal fraction of 0.66 control words per second (CW/s) has passed since the previous initialization of the scrambler; and   transmitting the generated first 188 byte data block and the at least second 188 byte data block.    
     
     
       43. The apparatus of claim 42, wherein the executable instructions further cause the processor to perform:
 not scrambling the header in the first 188 byte data block.    
     
     
       44. The apparatus of claim 42, wherein the executable instructions further cause the processor to perform:
 identifying the number of times the digital data has been copied and/or the number of times permitted to copy the digital data, based on copy prevention information included in the header of the first data block, the copy prevention information including at least one of current generation information and allowable generation information, the current generation information indicating the number of times the digital data has been copied and the allowable generation information indicating the number of times permitted to copy the digital data.    
     
     
       45. The apparatus of claim 42, wherein the executable instructions further cause the processor to perform:
 determining whether the digital data requires a copy prevention function based on identification information included in the header of the first data block, the identification information indicating whether or not at least a portion of the digital data has a data structure for copy prevention, and the controller is further configured to detect copy prevention information for controlling the copy prevention function from the digital data according to a result of this determination.    
     
     
       46. The method of claim 39, further comprising:
 determining whether the digital data requires a copy prevention function based on identification information included in the header of the first data block, the identification information indicating whether or not at least a portion of the digital data has a data structure for copy prevention; and   detecting copy prevention information for controlling the copy prevention function from the digital data according to a result of this determining step.