Video signal recording apparatus and video signal recording and reproducing apparatus

Abstract

An apparatus for recording and reproducing a digital video signal on and from a common recording medium by using the head configuration common to the conventional one while maintaining exchangeability with the current analog VTR. An analog video and audio signals are recorded and reproduced on and from an video track and an underlying deep-layer track, respectively, by means of magnetic heads and magnetic heads. On the other hand, a digital video and audio signal is recorded and reproduced on and from two adjacent tracks by means of the magnetic heads for analog audio recording. During reproduction, an identification signal generating circuit generates an identification signal for discriminating a recorded signal, and a control signal is PWM modulated with the identification signal and recorded on a control track by means of a magnetic head.

What is claimed is:  
     
         1 . A recording apparatus for selecting either an analog video signal or a digital information signal like a digital video signal, and for recording said selected signal on a magnetic tape, comprising: 
 a first magnetic head mounted at a first position on a rotary drum, and having a first azimuth angle;    a second magnetic head mounted at a second position on said rotary drum 180°-opposite to said first position, and having a second azimuth angle of a polarity opposite to said first azimuth angle, said first and second heads recording an audio signal in a deep layer of said magnetic tape along first recording tracks prior to recording of said analog video signal;    a third magnetic head mounted at a third position on said rotary drum, and having a third azimuth angle;    a fourth magnetic head mounted at a fourth position on said rotary drum 180°-opposite to said third position, and having a fourth azimuth angle of a polarity opposite to said third azimuth angle, said third and fourth magnetic heads recording said analog video signal in a surface layer of said magnetic tape along said first recording tracks and in superposition on said previously recorded audio signal; and    a servo means for rotating said rotary drum at a first rotation speed and for running said magnetic tape at a first transportation speed while recording said analog video signal and said audio signal, 
 wherein said servo means rotates said rotary drum at a second rotation speed and runs said magnetic tape at a second transportation speed while recording said digital information signal; and  
 wherein said first and second magnetic heads record said digital information signal on said magnetic tape along second recording tracks.  
   
     
     
         2 . A recording apparatus according to  claim 1 , wherein said first and second magnetic heads are metal heads, and have a gap length being equal to or less than a half recording wavelength of said digital information signal or 0.3 μm.  
     
     
         3 . A recording apparatus according to  claim 1 , wherein a track pitch of said second recording tracks is equal to or less than 29 μm.  
     
     
         4 . A recording apparatus according to  claim 1 , wherein a track pitch of said second recording tracks is equal to or greater than 21 μm and equal to or less than 26 μm.  
     
     
         5 . A recording apparatus according to  claim 1 , wherein a head width of said first and second magnetic heads is equal to or greater than 20 μm and equal to or less than 32 μm.  
     
     
         6 . A recording apparatus according to  claim 1 , wherein a head width of said first and second magnetic heads is 3 μm greater than a track pitch of said second recording tracks.  
     
     
         7 . A recording apparatus according to  claim 1 , wherein said first rotation speed is equal to a frame frequency of said analog video signal such as 30/1.001 rps or 25 rps and said second rotation speed is equal to or greater than 30/1.001 rps.  
     
     
         8 . A recording apparatus according to  claim 1 , wherein said first rotation speed is equal to a frame frequency of said analog video signal such as 30/1.001 rps or 25 rps and said second rotation speed is equal to 30/1.001 rps or 30 rps.  
     
     
         9 . A recording apparatus according to  claim 1 , further comprising: 
 means for generating an identification signal indicating that said selected signal to be recorded is said digital information signal; and    a fifth magnetic head for recording a tracking control signal on a linear track of said magnetic tape, 
 wherein said fifth magnetic head records said tracking control signal directly while recording said analog video signal, or records said tracking control signal modulated by said identification signal while recording said digital information signal.  
   
     
     
         10 . A recording apparatus according to  claim 1 , further comprising: 
 means for encoding said digital information signal in accordance with a predetermined format, said encoded digital information signal having a predetermined recording bit rate; and    a fifth magnetic head mounted at a fifth position on said rotary drum close to and approximately same height as said first magnetic head, and having said second azimuth angle, 
 wherein said encoding means encodes a first digital information signal having a predetermined transmission bit rate in accordance with said predetermined format, or encodes a second digital information signal having a transmission bit rate 1/N (N is an integer more than 1) times said predetermined transmission bit rate in accordance with said predetermined format and temporally compresses to 1/N, each of said encoded first and second digital information signals has said predetermined recording bit rate;  
 wherein said servo means runs said magnetic tape at said second transportation speed while recording said first digital information signal, or runs said magnetic tape at a third transportation speed 1/N times said second transportation speed while recording said second digital information signal; and  
 wherein said first and second magnetic heads record said encoded first digital information signal on said magnetic tape along said second recording tracks, or said first and second magnetic heads or said first and fifth magnetic heads record said encoded second digital information signal on said magnetic tape along said second recording tracks.  
   
     
     
         11 . A recording apparatus according to  claim 1 , further comprising: 
 means for encoding said digital information signal in accordance with a predetermined format, said encoded digital information signal having a predetermined recording bit rate; and    a fifth magnetic head mounted at a fifth position on said rotary drum close to and approximately one track pitch of said second recording tracks higher than said first magnetic head, and having a fifth azimuth angle, 
 wherein said encoding means encodes a first digital information signal having a predetermined transmission bit rate in accordance with said predetermined format, or encodes a second digital information signal having a transmission bit rate 1/N (N is an integer more than 1) times said predetermined transmission bit rate in accordance with said predetermined format and temporally compresses to 1/N, each of said encoded first and second digital information signals has said predetermined recording bit rate;  
 wherein said servo means runs said magnetic tape at said second transportation speed while recording said first digital information signal, or runs said magnetic tape at a third transportation speed 1/N times said second transportation speed while recording said second digital information signal; and  
 wherein said first and second magnetic heads record said encoded first digital information signal on said magnetic tape along said second recording tracks, or said first and second magnetic heads or said first and fifth magnetic heads record said encoded second digital information signal on said magnetic tape along said second recording tracks.  
   
     
     
         12 . A recording apparatus according to  claim 10 , further comprising: 
 a sixth magnetic head mounted at a sixth position on said rotary drum, and having said first azimuth angle; and    a seventh magnetic head mounted at a seventh position on said rotary drum 180°-opposite to said sixth magnetic head, and having said first azimuth angle, 
 wherein said encoding means encodes a third digital information signal having a transmission bit rate twice greater than said predetermined transmission bit rate in accordance with said predetermined format and distributes to two channels, said distributed signals of two channels have said predetermined recording bit rate respectively;  
 wherein said servo means runs said magnetic tape at a fourth transportation speed twice faster than said second transportation speed while recording said third digital information signal; and  
 wherein said second, sixth, fifth and seventh magnetic heads record said encoded third digital information signal on said magnetic tape along said second recording tracks.  
   
     
     
         13 . A recording apparatus according to  claim 11 , further comprising: 
 a sixth magnetic head mounted at a sixth position on said rotary drum close to said second magnetic head and approximately one track pitch of said second recording tracks higher than said second magnetic head, and having a sixth azimuth angle, 
 wherein said encoding means encodes a third digital information signal having a transmission bit rate twice greater than said predetermined transmission bit rate in accordance with said predetermined format and distributes to two channels, said distributed signals of two channels have said predetermined recording bit rate respectively;  
 wherein said servo means runs said magnetic tape at a fourth transportation speed twice faster than said second transportation speed while recording said third digital information signal; and  
 wherein said first, fifth, second and sixth magnetic heads record said encoded third digital information signal on said magnetic tape along said second recording tracks.  
   
     
     
         14 . A recording and reproducing apparatus for selecting either an analog video signal or a digital information signal like a digital video signal, and for recording said selected signal on a magnetic tape and reproducing said recorded signal, comprising: 
 a first magnetic head mounted at a first position on a rotary drum, and having a first azimuth angle;    a second magnetic head mounted at a second position on said rotary drum 180°-opposite to said first position, and having a second azimuth angle of a polarity opposite to said first azimuth angle, said first and second heads recording an audio signal in a deep layer of said magnetic tape along first recording tracks prior to recording of said analog video signal and reproducing said recorded audio signal;    a third magnetic head mounted at a third position on said rotary drum, and having a third azimuth angle;    a fourth magnetic head mounted at a fourth position on said rotary drum 180°-opposite to said third position, and having a fourth azimuth angle of a polarity opposite to said third azimuth angle, said third and fourth magnetic heads recording said analog video signal in a surface layer of said magnetic tape along said first recording tracks and in superposition on said previously recorded audio signal and reproducing said recorded analog video signal; and    a servo means for rotating said rotary drum at a first rotation speed and for running said magnetic tape at a first transportation speed while recording and reproducing said analog video signal and said audio signal, 
 wherein said servo means rotates said rotary drum at a second rotation speed and runs said magnetic tape at a second transportation speed while recording and reproducing said digital information signal; and  
 wherein said first and second magnetic heads record said digital information signal on said magnetic tape along second recording tracks and reproduce said recorded digital information signal.  
   
     
     
         15 . A recording and reproducing apparatus according to  claim 14 , wherein said first and second magnetic heads are metal heads, and have a gap length being equal to or less than a half recording wavelength of said digital information signal or 0.3 μm.  
     
     
         16 . A recording and reproducing apparatus according to  claim 14 , wherein a track pitch of said second recording tracks is equal to or less than 29 μm.  
     
     
         17 . A recording and reproducing apparatus according to  claim 14 , wherein a track pitch of said second recording tracks is equal to or greater than 21 μm and equal to or less than 26 μm.  
     
     
         18 . A recording and reproducing apparatus according to  claim 14 , wherein a head width of said first and second magnetic heads is equal to or greater than 20 μm and equal to or less than 32 μm.  
     
     
         19 . A recording and reproducing apparatus according to  claim 14 , wherein a head width of said first and second magnetic heads is 3 μm greater than a track pitch of said second recording tracks.  
     
     
         20 . A recording and reproducing apparatus according to  claim 14 , wherein said first rotation speed is equal to a frame frequency of said analog video signal such as 30/1.001 rps or 25 rps and said second rotation speed is equal to or greater than 30/1.001 rps.  
     
     
         21 . A recording and reproducing apparatus according to  claim 14 , wherein said first rotation speed is equal to a frame frequency of said analog video signal such as 30/1.001 rps or 25 rps and said second rotation speed is equal to 30/1.001 rps or 30 rps.  
     
     
         22 . A recording and reproducing apparatus according to  claim 14 , further comprising: 
 means for generating an identification signal indicating that said selected signal to be recorded is said digital information signal;    a fifth magnetic head for recording a tracking control signal on a linear track of said magnetic tape and reproducing said recorded tracking control signal; and    means for detecting said identification signal from a signal reproduced by said fifth magnetic head and discriminating that a recorded signal is said digital information signal, 
 wherein said fifth magnetic head records said tracking control signal directly while recording said analog video signal, or records said tracking control signal modulated by said identification signal while recording said digital information signal.  
   
     
     
         23 . A recording and reproducing apparatus according to  claim 14 , further comprising: 
 means for encoding said digital information signal in accordance with a predetermined format, said encoded digital information signal having a predetermined recording bit rate;    means for decoding said reproduced digital information signal in accordance with said predetermined format and generating said original digital information signal; and    a fifth magnetic head mounted at a fifth position on said rotary drum close to and approximately same height as said first magnetic head, and having said second azimuth angle, 
 wherein said encoding means encodes a first digital information signal having a predetermined transmission bit rate in accordance with said predetermined format, or encodes a second digital information signal having a transmission bit rate 1/N (N is an integer more than 1) times said predetermined transmission bit rate in accordance with said predetermined format and temporally compresses to 1/N, each of said encoded first and second digital information signals has said predetermined recording bit rate;  
 wherein said servo means runs said magnetic tape at said second transportation speed while recording and reproducing said first digital information signal, or runs said magnetic tape at a third transportation speed 1/N times said second transportation speed while recording and reproducing said second digital information signal;  
 wherein said first and second magnetic heads record said encoded first digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded first digital information signal, or said first and second magnetic heads or said first and fifth magnetic heads record said encoded second digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded second digital information signal; and  
 wherein said decoding means decodes said reproduced first digital information signal in accordance with said predetermined format and generating said original first digital information signal, or decodes said reproduced second digital information signal in accordance with said predetermined format, expands by a factor N and generating said original second digital information signal.  
   
     
     
         24 . A recording and reproducing apparatus according to  claim 14 , further comprising: 
 means for encoding said digital information signal in accordance with a predetermined format, said encoded digital information signal having a predetermined recording bit rate;    means for decoding said reproduced digital information signal in accordance with said predetermined format and generating said original digital information signal; and    a fifth magnetic head mounted at a fifth position on said rotary drum close to and approximately one track pitch of said second recording tracks higher than said first magnetic head, and having a fifth azimuth angle, 
 wherein said encoding means encodes a first digital information signal having a predetermined transmission bit rate in accordance with said predetermined format, or encodes a second digital information signal having a transmission bit rate 1/N (N is an integer more than 1) times said predetermined transmission bit rate in accordance with said predetermined format and temporally compresses to 1/N, each of said encoded first and second digital information signals has said predetermined recording bit rate;  
 wherein said servo means runs said magnetic tape at said second transportation speed while recording and reproducing said first digital information signal, or runs said magnetic tape at a third transportation speed 1/N times said second transportation speed while recording and reproducing said second digital information signal;  
 wherein said first and second magnetic heads record said encoded first digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded first digital information signal, or said first and second magnetic heads or said first and fifth magnetic heads record said encoded second digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded second digital information signal; and  
 wherein said decoding means decodes said reproduced first digital information signal in accordance with said predetermined format and generating said original first digital information signal, or decodes said reproduced second digital information signal in accordance with said predetermined format, expands by a factor N and generating said original second digital information signal.  
   
     
     
         25 . A recording and reproducing apparatus according to  claim 23 , further comprising: 
 a sixth magnetic head mounted at a sixth position on said rotary drum, and having said first azimuth angle; and    a seventh magnetic head mounted at a seventh position on said rotary drum 180° C.-opposite to said sixth magnetic head, and having said first azimuth angle, 
 wherein said encoding means encodes a third digital information signal having a transmission bit rate twice greater than said predetermined transmission bit rate in accordance with said predetermined format and distributes to two channels, said distributed signals of two channels have said predetermined recording bit rate respectively;  
 wherein said servo means runs said magnetic tape at a fourth transportation speed twice faster than said second transportation speed while recording and reproducing said third digital information signal;  
 wherein said second, sixth, fifth and seventh magnetic heads record said encoded third digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded third digital information signal; and  
 wherein said decoding means decodes said reproduced third digital information signal in accordance with said predetermined format, combines said decoded data of two channels and generating said original third digital information signal.  
   
     
     
         26 . A recording and reproducing apparatus according to  claim 24 , further comprising: 
 a sixth magnetic head mounted at a sixth position on said rotary drum close to said second magnetic head and approximately one track pitch of said second recording tracks higher than said second magnetic head, and having a sixth azimuth angle, 
 wherein said encoding means encodes a third digital information signal having a transmission bit rate twice greater than said predetermined transmission bit rate in accordance with said predetermined format and distributes to two channels, said distributed signals of two channels have said predetermined recording bit rate respectively;  
 wherein said servo means runs said magnetic tape at a fourth transportation speed twice faster than said second transportation speed while recording and reproducing said third digital information signal;  
 wherein said first, fifth, second and sixth magnetic heads record said encoded third digital information signal on said magnetic tape along said second recording tracks and reproduce said recorded third digital information signal; and  
 wherein said decoding means decodes said reproduced third digital information signal in accordance with said predetermined format, combines said decoded data of two channels and generating said original third digital information signal.