Video information recording and reproducing methods and apparatus

Abstract

Methods and apparatus for recording and subsequently reproducing video signals including video and synchronization information initially record the video signals and first control information distinct from said video and synchronization information on a recording medium. The video signals are subsequently reproduced with the aid of second control information being distinct from said video and synchronization information for controlling the reproduction of the video signals from the recording medium. The mentioned first control information is rendered incapable as recorded of controlling the reproduction of the video signals upon reproduction of the first control information, and the second control information is provided by reproducing the recorded first control information from the recording medium and converting at least part of the reproduced first control information to the second control information.

Claims

We claim:

1. In a method of recording and subsequently reproducing video signals including video and synchronization information, the improvement comprising in combination the steps of:

recording said video signals and first control information distinct from said video and synchronization information on a recording medium;

reproducing said video signals with the aid of second control information being distinct from said video and synchronization information for controlling the reproduction of said video information from said recording medium;

said first control information being rendered incapable as recorded of controlling the reproduction of said video signals upon reproduction of said first control information; and

said second control information being provided by reproducing said recorded first control information from said recording medium and converting at least part of said reproduced first control information to said second control information.

2. A method as claimed in claim 1, wherein:

said first control information is composed of a first part and a second part;

both said first and second parts of said control information are recorded and are subsequently reproduced; and

only said first part of the reproduced first control information is converted to said second control information for controlling the reproduction of said video information.

3. In a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard, the improvement comprising in combination the steps of:

providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

recording said video signals and said substandard control information on a recording medium;

reproducing said substandard control information with said reproduction equipment from said recording medium;

converting said reproduced substandard control information to control information conforming to said predetermined standard; and

reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

4. A method as claimed in claim 3, wherein:

said substandard control information is composed of a first part capable of being converted to control information conforming to said predetermined standard, and a second part for concealing the nature of said first part;

both said first and second parts of said substandard control information are recorded and are subsequently reproduced; and

only said first part of the reproduced substandard control information is converted to said standard control information for controlling continued reproduction of said recorded video information.

5. In a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring second control information distinct from said video and synchronization information and having at least a predetermined number of pulses per second, the improvement comprising in combination the steps of:

providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second;

recording said video signals and said first control information on a recording medium;

reproducing said first control information from said recording medium;

generating said second control information having at least said predetermined number of pulses per second with said reproduced first control information; and

reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with said generated second control information.

6. A method as claimed in claim 5, wherein:

said first control information is composed of a first signal for controlling generation of said second control information, and a second signal for concealing the nature of said first signal; and

both said first and second signals of said first control information are recorded and are subsequently reproduced.

7. In a method of recording video signals including video and synchronization information for subsequent reproduction with the aid of second control information for controlling the reproduction of said video signals, the improvement comprising in combination the steps of:

providing first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals but being convertible to said second control information;

recording said video signals and first control information distinct from said video and synchronization information; and

recording with said first control information a supplemental signal for concealing the nature of said first control information.

8. In a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination the steps of:

providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

recording said video signals and said substandard control information distinct from said video and synchronization information on a recording medium; and

recording with said substandard control information a supplemental signal for concealing the nature of said substandard control information.

9. In a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring second control information having at least a predetermined number of pulses per second, the improvement comprising in combination the steps of:

providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second for controlling generation of said second control information upon reproduction; and

recording said video signals and said first control information distinct from said video and synchronization information.

10. A method as claimed in claim 9, including the steps of:

composing said first control information of a first signal for controlling generation of said second control information upon reproduction, and a second signal for concealing the nature of said first signal; and

recording both said first and second signals of said first control information.

11. In a method of reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and being incapable of controlling the reproduction of said video signals, the improvement comprising in combination the steps of:

composing said recorded first control information of a recorded first part and a recorded second part for concealing the nature of said recorded first part;

reproducing both said recorded first and second parts of said first control information;

distinguishing said reproduced first part of said first control information from said reproduced second part;

converting said distinguished reproduced first part of said first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium; and

reproducing said video signals and controlling continued reproduction of said video signals from said recording medium with said second control information.

12. In a method of reproducing video signals including video and synchronization information having been recorded on a recording medium together with substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video signals from said recording medium, the improvement comprising in combination the steps of:

composing said recorded standard control information of a recorded first part capable of being converted to said standard control information and a recorded second part for concealing the nature of said first part;

reproducing both said recorded first and second parts of said substandard control information;

distinguishing said reproduced first part from said reproduced second part;

converting said reproduced first part of said substandard control information to said standard control information; and

reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information.

13. In a method of reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and having an insufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium, the improvement comprising in combination the steps of:

reproducing said first control information having said insufficient number of pulses per second;

generating with said reproduced first control information second control information having a sufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium; and

reproducing said video signals and controlling continued reproduction of said video signals from said recording medium with said generated speed control information.

14. A method as claimed in claim 13, wherein:

said first control information is composed of a first signal for controlling generation of said second control information, and a second signal for concealing the nature of said first signal;

both said first and second signals are reproduced from said recording medium; and

only said reproduced first signal is employed for generation of said second control information.

15. In apparatus for recording and subsequently reproducing video signals including video and synchronization information on and from a recording medium, the improvement comprising in combination:

means for recording said video signals and first control information distinct from said video and synchronization information on said recording medium;

means for reproducing said video information with the aid of second control information being distinct from said video and synchronization information for controlling the reproduction of said video signals from said recording medium;

said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the reproduction of said video signals upon reproduction of said first control information; and

said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said recording medium and means for converting at least part of the reproduced first control information to said second control information.

16. An apparatus as claimed in claim 15, wherein:

said apparatus includes means for composing said first control information of a first part and a second part;

said recording means include means for recording both said first and second parts of said control information;

said apparatus include means for reproducing said first and second control information parts; and

said second control information providing means include means for converting only said first part of the reproduced first control information to said second control information for controlling the reproduction of said video signals.

17. In apparatus for recording video signals including video and synchronizing information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

means for recording said video signals and said substandard control information on said recording medium;

means for reproducing said substandard control information with said reproduction equipment from said recording medium;

means connected to said control information reproducing means for converting said reproduced substandard control information to control information conforming to said predetermined standard;

means for reproducing said video signals; and

means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

18. An apparatus as claimed in claim 17, wherein:

said apparatus includes means for composing said substandard control information of a first part capable of being converted to control information conforming to said predetermined standard, and a second part for concealing the nature of said first part;

said recording means include means for recording both said first and second parts of said substandard control information;

said converting means include means for converting only said first part of the reproduced substandard control information to said standard control information for controlling continued reproduction of said recorded video signals.

19. In apparatus for recording video signals including video and synchronization information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring second control information having at least a predetermined number of pulses per second, the improvement comprising in combination:

means for providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second;

means for recording said video signals and said first control information on said recording medium;

means for reproducing said first control information from said recording medium;

means connected to said reproducing means for generating said second control information having at least said predetermined number of pulses per second with said reproduced first control information; and

means for reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with said generated second control information.

20. An apparatus as claimed in claim 19, wherein:

said apparatus includes means for composing said first control information of a first signal for controlling generation of said second control information, and a second signal for concealing the nature of said first signal; and

said recording means include means for recording both said first and second signals of said first control information.

21. In apparatus for recording video signals including video and synchronization information for subsequent reproduction with the aid of second control information for controlling the reproduction of said video information, the improvement comprising in combination:

means for providing first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video information but being convertible to said second control information:

means connected to said control information providing means for recording said video signals and first control information; and

means for recording with said first control information a supplemental signal for concealing the nature of said first control information.

22. In apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

means connected to said control information providing means for recording said video signals and said substandard control information on said recording medium; and

means for recording with said substandard control information a supplemental signal for concealing the nature of said substandard control information.

23. In apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring second control information having at least a predetermined number of pulses per second, the improvement comprising in combination:

means for providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second for controlling generation of said second control information upon reproduction; and

means connected to said control information providing signals for recording said video signals and said first control information.

24. An apparatus as claimed in claim 23, including:

means for composing said first control information of a first signal for controlling generation of said second control information upon reproduction, and a second signal for concealing the nature of said first signal; and

means for recording both said first and second signals of said first control information.

25. In apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information, being incapable and being composed of a recorded first part and a recorded second part for concealing the nature of said recorded first part, the improvement comprising in combination:

means for reproducing both said recorded first and second parts of said first control information;

means connected to said reproducing means for converting said reproduced first part of said first control information to second control information distinct from said video and synchronization information for controlling reproducing of said video signals from said recording medium;

means for reproducing said video signals; and

means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information.

26. In apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video information from said recording medium, said substandard control information being composed of a first part capable of being converted to said standard control information and a second part for concealing the nature of said first part, the improvement comprising in combination:

means for reproducing both said first and second parts of said substandard control information;

means connected to said reproducing means for converting said reproduced first part of said substandard control information to said standard control information;

means for reproducing said video signals; and

means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information.

27. In apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and having an insufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium, the improvement comprising in combination:

means for reproducing said first control information having said insufficient number of pulses per second;

means connected to said reproducing means for generating with said reproduced first control information second control information having a sufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium; and

means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information.

28. In apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied, in a first case, by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals and, in a second case, by second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals, the improvement comprising in combination:

means for reproducing said first control information in said first case and said second control information in said second case;

means connected to said reproducing means for converting in said first case at least part of said reproduced first control information to third control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium;

means for reproducing said video signals; and

means for controlling reproduction of said video signals from said recording medium in said first case with said third control information, and in said second case with said second control information.

29. An apparatus as claimed in claim 28, including:

means connected to said control information reproducing means for distinguishing the presence of reproduced second control information from the presence of reproduced first control information; and

means connected to said distinguishing means and to said converging means for inhibiting the function of said converting means during the presence of reproduced second control information.

30. In apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals, the improvement comprising in combination:

means for reproducing said first control information;

means for reproducing said video signals from said recording medium including rotary reproducing means and means for rotating said video signal reproducing means relative to said recording medium;

means connected to said control information reproducing means for converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium;

means connected to said converting means for modifying a phase of said second control information in accordance with an operation of said rotating video signal reproducing means; and

means for controlling reproduction of said video signals from said recording medium with said phase modified second control information.

31. An apparatus as claimed in claim 30, wherein:

said first control information comprises a number of first pulses being insufficient to effect control of said reproduction of the video signals;

said converting means include means for providing said second control information with a number of second pulses sufficient to effect control of said reproduction of the video signals; and

said modifying means include means for shifting the phase of said second pulses into correspondence with an operation of said video signal providing means.

32. An apparatus as claimed in claim 30 wherein:

said modifying means include means for shifting the phase of said second control information to the phase of said reproduced first control information.

33. In apparatus for recording and subsequently playing back video signals including video and synchronization information on and from a recording medium, the improvement comprising in combination:

means for recording said video signals and first control information distinct from said video and synchronization information on said recording medium;

playback means for effecting a playback of said video information from said recording medium;

means connected to said playback means for controlling the playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information;

said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the playback of said video signals upon reproduction of said first information; and

said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said recording medium and means for converting at least part of the reproduced first control information to said second control information.

34. In apparatus for recording video signals including video and synchronization information on a recording medium and subsequently playing back said video signals with playback equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

means for recording said video signals and said substandard control information on said recording medium;

mean for playing back said substandard control information with said playback equipment from said recording medium;

means connected to said control information playback means for converting said played back substandard control information to control information conforming to said predetermined standard;

playback means for playing back said video signals; and

means connected to said converting means for controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

35. In a method of recording and subsequently reproducing video signals including video and synchronization information, the improvement comprising in combination the steps of:

establishing on the same recording medium a record of said video signals including said video and synchronization information and a further record of control information distinct from said video and synchronization information;

reproducing said video signals with the aid of second control information being distinct from said video and synchronization information;

said first control information as present in said further record being incapable of controlling the reproduction of said video signals upon reproduction of said first control information; and

said second control information being provided by reproducing said recorded first control information from said further record and converting at least part of said reproduced first control information to said second control information.

36. In a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard, the improvement comprising in combination the steps of:

providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

establishing on the same recording medium a record of said video signals and a further record of said substandard control information;

reproducing said substandard control information with said reproduction equipment from said recording medium;

converting said reproduced substandard control information to control information conforming to said predetermined standard; and

reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

37. In a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination the steps of:

providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard; and

establishing on the same recording medium a record of said video signals including said video and synchronization information, and a further record of said substandard control information distinct from said record of said video signals including video and synchronization information on a recording medium.

38. In a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals, the improvement comprising in combination the steps of:

reproducing said first control information from said second record on said recording medium;

converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium; and

reproducing said video signals including said video and synchronization information from said first record on said recording medium and controlling continued reproduction of said video signals from said first record on said recording medium with said second control information.

39. In a method of recording and subsequently reproducing video signals including video and synchronization information, the improvement comprising in combination the steps of:

establishing on the same recording medium a record of said video signals and a further record of first control information distinct from said video and synchronization information;

effecting a playback of said video signals from said recording medium and controlling said playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information;

said first control information as recorded in said further record being incapable of controlling the playback of said video signals upon reproduction of said first control information; and

said second control information being provided by reproducing said recorded first control information from said further record or said recording medium and converting at least part of said reproduced first control information to said second control information.

40. In a method of recording video signals including video and synchronization information and subsequently playing back said video signals with playback equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard, the improvement comprising in combination the steps of:

providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

establishing on the same recording medium a record of said video signals and a further record of said substandard control information;

effecting a playback of said substandard control information with said playback equipment from said further record on said recording medium;

converting said played back substandard control information to control information conforming to said predetermined standard; and

effecting a playback of said video signals and controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

41. In apparatus for recording and subsequently reproducing video signals including video and synchronization information on and from a recording medium, the improvement comprising in combination:

means for establishing on said recording medium a record of said video signals including said video and synchronization information and, on the same recording medium, a further record of first control information distinct from said video and synchronization information;

means for reproducing said video information with the aid of second control information being distinct from said video and synchronization information;

said apparatus including means for rendering said first control information as present in said further record incapable of controlling the reproduction of said video signals upon reproduction of said first control information; and

said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said further record and means for converting at least part of the reproduced first control information to said second control information.

42. In apparatus for recording video signals including video and synchronization information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, said control information providing means including means for rendering said substandard control information incapable, prior to its conversion to control information conforming to said predetermined standard, of controlling reproduction of said recorded video signals from said recording medium;

means for establishing on said recording medium a record of said video signals and a further record of said substandard control information;

means for reproducing said substandard control information with said reproduction equipment from said further record on said recording medium;

means connected to said control information reproducing means for converting said reprodced substandard control information to control information conforming to said predetermined standard;

means for reproducing said video signals; and

means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

43. In apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, said control information providing means including means for rendering said substandard control information incapable, prior to its conversion to control information conforming to said predetermined standard, of controlling reproduction of said recorded video signals from said recording medium; and

means connected to said control information providing means for recording said video signals and said substandard control information on said recording medium.

44. In apparatus for recording and subsequently playing back video signals including video and synchronization information on and from a recording medium, the improvement comprising in combination:

means for establishing on said recording medium a record of said video signals and on the same recording medium a further record of said first control information distinct from said video and synchronization information;

playback means for effecting a playback of said video information from said recording medium;

means connected to said playback means for controlling the playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information;

said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the playback of said video signals upon reproduction of said first control information; and

said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said further record on said recording medium and means for converting at least part of the reproduced first control information to said second control information.

45. In apparatus for recording video signals including video and synchronization information on a recording medium and subsequently playing back said video signals with playback equipment requiring control information conforming to a predetermined standard, the improvement comprising in combination:

means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard;

means for establishing on the same recording medium a record of said video signals and a further record of said substandard control information;

means for playing back said substandard control information with said playback equipment from said further record on said recording medium;

means connected to said control information playback means for converting said played back substandard control information to control information conforming to said predetermined standard;

playback means for playing back said video signals; and

means connected to said converting means for controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

46. In a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals, the improvement comprising in combination the steps of:

reproducing said first control information from said second record on said recording medium;

converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium; and

reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium; and

controlling the velocity of said playback head means with said second control information.

47. In a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video signals from said recording medium, the improvement comprising in combination the steps of:

reproducing said substandard control information from said second record on said recording medium;

converting said reproduced substandard control information to said standard control information; and

reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium; and

controlling the velocity of said playback head means with said second control information.

48. In apparatus for reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals, the improvement comprising in combination:

means for reproducing said first control information from said second record on said recording medium;

means connected to said reproducing means for converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium;

means for reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium; and

means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information, said controlling means including means for controlling the velocity of said playback head means with said second control information.

49. In apparatus for reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video information from said recording medium, the improvement comprising in combination:

means for reproducing said substandard control information from said second record on said recording medium;

means connected to said reproducing means for converting said reproduced substandard control information to said standard control information;

means reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium; and

means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information, said controlling means including means for controlling the velocity of said playback head means with said second control information.

50. In apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied, in a first case, by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals and, in a second case, by second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals, the improvement comprising in combination:

means for reproducing said first control information in said first case and said second control information in said second case;

means connected to said reproducing means for converting in said first case at least part of said reproduced first control information to third control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium;

means for reproducing said video signals with playback head means moving relatively to said recording medium; and

means for controlling reproduction of said video signals from said recording medium in said first case with said third control information, and in said second case with said second control information, said reproduction controlling means including means for controlling the velocity of said playback head means with said third control information in said first case, and with said second control information in said second case.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject invention relates to methods and apparatus for recording and reproducing video information and, more specifically, to such methods and apparatus wherein theft, unauthorized reproduction and/or unauthorized copying of video recordings are substantially impeded.

2. Description of the Prior Art

The problem of theft, unauthorized reproduction and/or unauthorized copying of video recordings has become acute with the proliferation of video recording and/or reproduction equipment.

Unfortunately, video signal scrambling techniques of the type employed in video signal transmission are not suitable to adaptation to the video recording field, as such techniques tend to degrade the recorded and reproduced video signal, render the recording and reproduction equipment too complex and expensive and increase down time and service problems.

By way of example, reference is made to the television scrambling system disclosed in U.S. Pat. No. 3,460,161, by P. J. Waller et al, issued Aug. 5, 1969. In that and similar prior-art systems, scrambling is practiced on the television signal itself, by deliberately degrading the horizontal synchronization signal and introducing spurious signals that will disturb the video synchronization process in the receiver. Practice of that system also involves a distrubance of the video information, in that the picture waveforms are shifted in time and cut off on one side.

SUMMARY OF THE INVENTION

It is a general object of this invention to overcome the above mentioned disadvantages.

It is a more specific object of this invention to provide video recording and reproducing methods and apparatus which employ improved techniques and equipment for impeding theft, unauthorized reproduction and unauthorized copying of video recordings.

It is a germane object of this invention to provide improved video recording and reproducing methods and apparatus which do not resort to degradation or modification of the picture signal or synchronization information but still provide effective protection against theft, unauthorized reproduction and unauthorized copying of video recordings.

It is also an object of this invention to exploit every area of utility for which the methods and apparatus herein disclosed are suitable with or without modifications and variations within the spirit and scope of the subject invention.

Other objects will appear in the further course of this disclosure.

From one aspect thereof, the invention resides in a method of recording and subsequently reproducing video signals including video and synchronization information. The invention according to this aspect resides, more, specifically, in the improvement comprising in combination the steps of recording said video signals and first control information distinct from said video and synchronization information on a recording medium, reproducing said video signals with the aid of second control information being distinct from said video and synchronization information for controlling the reproduction of said video information from said recording medium, said first control information being rendered incapable as recorded of controlling the reproduction of said video signals upon reproduction of said first control information, and said second control information being provided by reproducing said recorded first control information from said recording medium and converting at least part of said reproduced first control information to said second control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, recording said video signals and said substandard control information on a recording medium, reproducing said substandard control information with said reproduction equipment from said recording medium, converting said reproduced substandard control information to control information conforming to said predetermined standard, and reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring second control information distinct from said video and synchronization information and having at least a predetermined number of pulses per second. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second, recording said video signals and said first control information on a recording medium, reproducing said first control information from said recording medium, generating said second control information having at least said predetermined number of pulses per second with said reproduced first control information, and reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with said generated second control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent reproduction with the aid of second control information for controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals but being convertible to said second control information, recording said video signals and first control information distinct from said video and synchronization information, and recording with said first control information a supplemental signal for concealing the nature of said first control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, recording said video signals and said substandard control information distinct from said video and synchronization information on a recording medium, and recording with said substandard control information a supplemental signal for concealing the nature of said substandard control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring second control information having at least a predetermined number of pulses per second. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second for controlling generation of said second control information upon reproduction, and recording said video signals and said first conntrol information distinct from said video and synchronization information.

From another aspect thereof, the invention resides in a method of reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and being incapable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of composing said recorded first control information of a recorded first part and a recorded second part for concealing the nature of said recorded first part reproducing both said recorded first and second parts of said first control information, distinguishing said reproduced first part of said first control information from said reproduced second part, converting said distinguished reproduced first part of said first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium, and reproducing said video signals and controlling continued reproduction of said video signals from said recording medium with said second control information.

From another aspect thereof, the invention resides in a method of reproducing video signals including video and synchronization information having been recorded on a recording medium together with substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video signals from said recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of composing said recorded substandard control information of a recorded first part capable of being converted to said standard control information and a recorded second part for concealing the nature of said first part, reproducing both of said recorded first and second parts of said substandard control information, distinguishing said reproduced first part from said reproduced second part, converting said reproduced first part of said substandard control information to said standard control information, and reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information.

From another aspect thereof, the invention resides in a method of reproducing video signals including video and symchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and having an insufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of reproducing said first control information having said insufficient number of pulses per second, generating with said reproduced first control information second control information having a sufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium, and reproducing said video signals and controlling continued reproduction of said video signals from said recording medium with said generated second control information.

From another aspect thereof, the invention resides in apparatus for recording and subsequently reproducing video signals including video and synchronization information on and from a recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for recording said video signals and first control information distinct from said video and synchronization information on said recording medium, means for reproducing said video information with the aid of second control information being distinct from said video and synchronization information for controlling the reproduction of said video signals from said recording medium, said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the reproduction of said video signals upon reproduction of said first control information, and said apparatus including means for providing said second control information, said second control signal providing means including means for reproducing said recorded first control information from said recording medium and means for converting at least part of the reproduced first control information to said second control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, means for recording said video signals and said substandard control information on said recording medium, means for reproducing said substandard control information with said reproduction equipment from said recording medium, means connected to said control information reproducing means for converting said reproduced substandard control information to control information conforming to said predetermined standard, means for reproducing said video signals, and means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring second control information having at least a predetermined number of pulses per second. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second, means for recording said video signals and said first control information on said recording medium, means for reproducing said first control information from said recording medium, means connected to said reproducing means for generating said second control information having at least said predetermined number of pulses per second with said reproduced first control information, and means for reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with said generated second control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information for subsequent reproduction with the aid of second control information for controlling the reproduction of said video information. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video information but being convertible to said second control information, means connected to said control information providing means for recording said video signals and first control information, and means for recording with said first control information a supplemental signal for concealing the nature of said first control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, means connected to said control information providing means for recording said video signals and said substandard control information on said recording medium, and means for recording with said substandard control information a supplemental signal for concealing the nature of said substandard control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring second control information having at least a predetermined number of pulses per second. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing first control information distinct from said video and synchronization information and having less than said predetermined number of pulses per second for controlling generation of said second control information upon reproduction, and means connected to said control information providing signals for recording said video signals and said first control information.

From another aspect thereof, the invention resides in apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information, being incapable of controlling the reproduction of said video signals and being composed of a recorded first part and a recorded second part for concealing the nature of said recorded first part. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing both said recorded first and second parts of said first control information, means connected to said reproducing means for converting said reproduced first part of said first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium, means for reproducing said video signals, and means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video information from said recording medium, said substandard control information being composed of a first part capable of being converted to said standard control information and a second part for concealing the nature of said first part. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing both said first and second parts of said substandard control information, means connected to said reproducing means for converting said reproduced first part of said substandard control information to said standard control information, means for reproducing said video signals, and means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information.

From another aspect thereof, the invention resides in apparatus for reproducing video signals including video and synchronization information having been recorded on a recording medium together with first control information distinct from said video and synchronization information and having an insufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said first control information having said insufficient number of pules per second, means connected to said reproducing means for generating with said reproduced first control information second control information having a sufficient number of pulses per second for controlling the reproduction of said video signals from said recording medium, and means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied, in a first case, by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals and, in a second case, by second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said first control information in said first case and said second control information in said second case, means connected to said reproducing means for converting in said first case at least part of said reproduced first control information to third control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium, means for reproducing said video signals, and means for controlling reproduction of said video signals from said recording medium in said first case with said third control information, and in said second case with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said first control information, means for reproducing said video signals from said recording medium including rotary reproducing means and means for rotating said video signal reproducing means relative to said recording medium, means connected to said control information reproducing means for converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium, means connected to said converting means for modifying a phase of said second control information in accordance with an operation of said rotating video signal reproducing means, and means for controlling reproduction of said video signals from said recording medium with said phase modified second control information.

From another aspect thereof, the invention resides in apparatus for recording and subsequently playing back video signals including video and synchronization information on and from a recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for recording said video signals and first control information distinct from said video and synchronization information on said recording medium, playback means for effecting a playback of said video information from said recording medium, means connected to said playback means for controlling the playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information, said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the playback of said video signals upon reproduction of said first control information, and said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said recording medium and means for converting at least part of the reproduced first control information to said second control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information on a recording medium and subsequently playing back said video signals with playback equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, means for recording said video signals and said substandard control information on said recording medium, means for playing back said substandard control information with said playback equipment from said recording medium, means connected to said control information playback means for converting said played back substandard control information to control information conforming to said predetermined standard, playback means for playing back said video signals, and means connected to said converting means for controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information for subsequent playback with the aid of second control information for controlling the playback of said video information. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing first control information distinct from said video and synchronization information and incapable of controlling the playback of said video information but being convertible to said second control information for controlling the playback of said video signals from a recording medium, and means connected to said first control information providing means for recording said video signals and first control information.

From another aspect thereof, the invention resides in a method of recording and subsequently reproducing video signals including video and synchronization information. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of establishing on the same recording medium a record of said video signals including said video and synchronization information and a further record of control information distinct from said video and synchronization information, reproducing said video signals with the aid of second control information being distinct from said video and synchronization information, said first control information as present in said further record being incapable of controlling the reproduction of said video signals upon reproduction of said first control information, and said second control information being provided by reproducing said recorded first control information from said further record and converting at least part of said reproduced first control information to said second control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information and subsequently reproducing said video signals with reproduction equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, establishing on the same recording medium a record of said video signals and a further record of said substandard control information, reproducing said substandard control information with said reproduction equipment from said recording medium, converting said reproduced substandard control information to control information conforming to said predetermined standard, and reproducing said video signals and controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent reproduction with the aid of second control information for controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals but being convertible to said second control information, and establishing on the same recording medium a record of said video signals including said video and synchronization information and a further record of said further control information distinct from said video and synchronization information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, and establishing on the same recording medium a record of said video signals including said video and synchronization information, and a further record of said substandard control information distinct from said record of said video signals including video and synchronization information on a recording medium.

From another aspect thereof, the invention resides in a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of reproducing said first control information from said second record on said recording medium, converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium, and reproducing said video signals including said video and synchronization information from said first record on said recording medium and controlling continued reproduction of said video signals from said first record on said recording medium with said second control information.

From another aspect thereof, the invention resides in a method of recording and subsequently reproducing video signals including video and synchronization information. The invention according to this aspect resides, more specifically in the improvement comprising in combination the steps of establishing on the same recording medium a record of said video signals and a further record of first control information distinct from said video and synchronization information, effecting a playback of said video signals from said recording medium and controlling said playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information, said first control information as recorded in said further record being incapable of controlling the playback of said video signals upon reproduction of said first control information, and said second control information being provided by reproducing said recorded first control information from said further record on said recording medium and converting at least part of said reproduced first control information to said second control information.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information and subsequently playing back said video signals with playback equipment requiring control information distinct from said video and synchronization information and conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, establishing on the same recording medium a record of said video signals and a further record of said substandard control information, effecting a playback of said substandard control information with said playback equipment from said further record on said recording medium, converting said played back substandard control information to control information conforming to said predetermined standard, and effecting a playback of said video signals and controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in a method of recording video signals including video and synchronization information for subsequent playback with the aid of second control information for controlling the playback of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of providing first control information distinct from said video and synchronization information and incapable of controlling the playback of said video signals but being convertible to said second control information for controlling the playback of said video signals from a recording medium, and establishing on the same recording medium a record of said video signals including said video and synchronization information, and a further record of said first control information distinct from said record of said video signals including video and synchronization information.

From another aspect thereof, the invention resides in apparatus for recording and subsequently reproducing video signals including video and synchronization information on and from a recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for establishing on said recording medium a record of said video signals including said video and synchronization information and, on the same recording medium, a further record of first control information distinct from said video and synchronization information, means for reproducing said video information with the aid of second control information being distinct from said video and synchronization information, said apparatus including means for rendering said first control information as present in said further record incapable of controlling the reproduction of said video signals upon reproduction of said first control information, and said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said further record and means for converting at least part of the reproduced first control information to said second control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information on a recording medium and subsequently reproducing said video signals with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, said control information providing means including means for rendering said substandard control information incapable, prior to its conversion to control information conforming to said predetermined standard, of controlling reproduction of said recorded video signals from said recording medium, means for establishing on said recording medium a record of said video signals and a further record of said substandard control information, means for reproducing said substandard control information with said reproduction equipment from said further record on said recording medium, means connected to said control information reproducing means for converting said reproduced substandard control information to control information conforming to said predetermined standard, means for reproducing said video signals, and means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information for subsequent reproduction with reproduction equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, said control information providing means including means for rendering said substandard control information incapable, prior to its conversion to control information conforming to said predetermined standard, of controlling reproduction of said recorded video signals from said recording medium, and means connected to said control information providing means for recording said video signals and said substandard control information on said recording medium.

From another aspect thereof, the invention resides in apparatus for recording and subsequently playing back video signals including video and syncrhonization information on and from a recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for establishing on said recording medium a record of said video signals and on the same recording medium a further record of said first control information distinct from said video and synchronization information, playback means for effecting a playback of said video information from said recording medium, means connected to said playback means for controlling the playback of said video signals from said recording medium with second control information being distinct from said video and synchronization information, said apparatus including means connected to said recording means for rendering said first control information incapable as recorded of controlling the playback of said video signals upon reproduction of said first control information, and said apparatus including means for providing said second control information, said second control information providing means including means for reproducing said recorded first control information from said further record on said recording means and means for converting at least part of the reproduced first control information to said second control information.

From another aspect thereof, the invention resides in apparatus for recording video signals including video and synchronization information on a recording medium and subsequently playing back said video signals with playback equipment requiring control information conforming to a predetermined standard. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for providing substandard control information distinct from said video and synchronization information and capable of being converted to control information conforming to said predetermined standard, means for establishing on the same recording medium a record of said video signals and a further record of said substandard control information, means for playing back said substandard control information with said playback equipment from said further record on said recording medium, means connected to said control information playback means for converting said played back substandard control information to control information conforming to said predetermined standard, playback means for playing back said video signals, and means connected to said converting means for controlling continued playback of said recorded video signals from said recording medium with the latter control information conforming to said predetermined standard.

From another aspect thereof, the invention resides in a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of reproducing said first control information from said second record on said recording medium, converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium, and reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium, and controlling the velocity of said playback head means with said second control information.

From another aspect thereof, the invention resides in a method of reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video signals from said recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising in combination the steps of reproducing said substandard control information from said second record on said recording medium, converting said reproduced substandard control information to said standard control information, and reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium, and controlling the velocity of said playback head means with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said first control information from said second record on said recording medium, means connected to said reproducing means for converting at least part of said reproduced first control information to second control information distinct from said video and synchronization information for controlling reproduction of said video signals from said recording medium, means for reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium, and means connected to said converting means for controlling reproduction of said video signals from said recording medium with said second control information, said controlling means including means for controlling the velocity of said playback head means with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing recorded video signals including video and synchronization information from a first record on a recording medium bearing also a second record of substandard control information distinct from said video and synchronization information and capable of being converted to standard control information for controlling reproduction of said video information from said recording medium. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said substandard control information from said second record on said recording medium, means connected to said reproducing means for converting said reproduced substandard control information to said standard control information, means reproducing said video signals from said first record on said recording medium with playback head means moving relatively to said recording medium, and means connected to said converting means for controlling continued reproduction of said recorded video signals from said recording medium with the latter standard control information, said controlling means including means for controlling the velocity of said playback head means with said second control information.

From another aspect thereof, the invention resides in apparatus for reproducing from a recording medium recorded video signals including video and synchronization information and being accompanied, in a first case, by first control information distinct from said video and synchronization information and incapable of controlling the reproduction of said video signals and, in a second case, by second control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals. The invention according to this aspect resides, more specifically, in the improvement comprising, in combination, means for reproducing said first control information in said first case and said second control information in said second case, means connected to said reproducing means for converting in said first case at least part of said reproduced first control information to third control information distinct from said video and synchronization information and capable of controlling the reproduction of said video signals from said recording medium, means for reproducing said video signals with playback head means moving relatively to said recording medium, and means for controlling reproduction of said video signals from said recording medium in said first case with said third control information, and in said second case with said second control information, said reproduction controlling means including means for controlling the velocity of said playback head means with said third control information in said first case, and with said second control information in said second case.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become more readily apparent from the following detailed description of preferred embodiments thereof, illustrated by way of example in the accompanying drawings, in which:

FIG. 1 is a diagrammatic top view of essential parts of a tape recording and playback apparatus as may be employed in the practice of the subject invention;

FIGS. 2 and 3 constitute a circuit diagram of servo control equipment that may be employed in the apparatus of FIG. 1;

FIG. 4 is a diagrammatic showing of part of a tape recording produced by the apparatus of FIG. 1;

FIGS. 5 and 6 constitute a logic circuit diagram of a control signal encoder in accordance with a preferred embodiment of the subject invention;

FIGS. 7 and 8 constitute a logic circuit diagram of a control signal decoder in accordance with a further preferred embodiment of the subject invention;

FIGS. 9a, 9b and 9c are diagrammatic representations of waveforms explaining the operation of part of the equipment herein disclosed;

FIGS. 10, 11 and 12 show how the FIGS. 2 and 3, 5 and 6, and 7 and 8, respectively, are to be juxtaposed;

FIGS. 13 and 14 constitute a logic circuit diagram of a control signal encoder in accordance with a further preferred embodiment of the subject invention;

FIGS. 15, 16, 17 and 18 constitute a logic circuit diagram of a control signal decoder in accordance with a further preferred embodiment of the subject invention;

FIG. 19 shows how FIGS. 13 and 14 are to be juxtaposed; and

FIG. 20 shows how FIGS. 15 to 18 are to be juxtaposed.

DESCRIPTION OF PREFERRED EMBODIMENTS

In order to disclose the subject invention within the frame work of one of its possible settings and in order to set forth the best mode presently contemplated of carrying out this invention, the subject matter of FIGS. 1 and 2 has been developed with reference to the videocassette recorder type VO-1600, manufactured by Sony Corporation. In this connection, reference may, for instance, be had to the Sony Service Manual VO-1600, published 1972.

FIG. 1 diagrammatically shows a head drum assembly of a video tape recording and reproducing apparatus 11. The head drum assembly 10 has a rotary support 12 for a pair of video recording and playback heads 13 and 14. Recording tape 15 from a tape cassette or other tape supply and takeup means (not shown) is guided by rollers 16 to the head drum assembly and by rollers 17 from the head drum assembly. Some of these rollers may be part of conventional tape threading equipment as, for instance, disclosed in the above mentioned Service Manual.

The head support 12 and heads 13 and 14 are rotated by a conventional drive (not shown). The tape is advanced by a nip roller and capstan assembly 19 which is also driven by conventional means (not shown).

As is well known in the video recording art, equipment of the type shown in FIG. 1 records the video signal in a slant-track pattern on the video tape 15. By way of example, such a slant-track pattern for the video information is shown at 21 in FIG. 4.

In this type of video recorder, it is also customary to record signals for control purposes on the tape. This is typically done in a separate control track as shown, by way of example, at 23 in FIG. 4. A magnetic recording and playback head for recording and playing back control signals from the track 23 is shown at 24 in FIG. 1. One or more conventional recording and playback heads (not shown) may also be employed in accordance with standard practice for recording and reproducing audio signals onto and from one or more audio tracks 25.

A representative type of servo control for the above mentioned type of video recording and playback equipment is shown by way of example in FIGS. 2 and 3 which should be juxtaposed as shown in FIG. 10. In this connection, reference may again be had to the above mentioned Service Manual or videocassette recorder.

By way of general comment, the recording and playback equipment herein under consideration employs a braking-type servo system to control the velocity of the video recording and playback head rotation. In addition to the control signal recording and playback head 24 shown in FIGS. 1 and 2, there are two further magnetic pickup devices 28 and 29 shown below the control signal head 24 in FIG. 2.

The devices 28 and 29 pick up the position of the video heads 13 and 14, respectively. These pickup devices are of a conventional type and, in a conventional manner, generate a pulse whenever they are passed by a magnetically active vane or other rotating conventional device (not shown) which is located on the rotating head assembly to indicate video head position.

Upon playback, the servo control shown in FIGS. 2 and 3 compares the control signals played back by the head 24 with the signals generated by the pickup devices 28 and 29. If this comparison indicates that the video head velocity is too high, the braking current in a conventional braking device 31 is increased so as to retard the video head position. On the other hand, the braking current is lessened in response to an indication that the video heads 13 and 14 lag the desired velocity.

In the recording mode, seprated sync signals obtained from the video signal serve as timing reference for the illustrated servo system.

In the servo control shown in FIGS. 2 and 3, a terminal 41, jumper 42 and terminal 43 connect the control signal head 24 to a preamplifier 45 including transistors 46, 47 and 48. The output pulses of the preamplifier 45 are applied via terminal 51, jumper 52 and terminal 53 to a lead 54.

When a tracking control switch 56 shown in FIG. 3 is in its off position, the output pulses of the preamplifier 45 are applied to a monostable multivibrator 57. These output pulses are also applied to a multivibrator 58 of a variable delay system that provides variable tracking. This variable delay system includes the multivibrator 58 and a multivibrator 59 connected in cascade. The RC network that determines the duration of the unstable state of the multivibrator 59 is returned to a variable bias source at a transistor 61, whose emitter voltage is controlled by a voltage divider that includes the variable resistor 62 of a tracking control.

In the on position of the tracking control switch 56, delayed played-back tracking control pulses are applied to the above mentioned multivibrator 59. This multivibrator generates a pulse to be formed into a sampling ramp in the succeeding stage. The multivibrator 57 is connected to a Miller integrator 63 that generates a negative-going ramp. The amplitude of this ramp is sampled by a sampling hold gate 64 which is turned on by a delayed pulse generated by the pickup device 28 upon each pass made by the video head 13. A capacitor 65 is charged to the value of the ramp and holds its charge until the next pulse is picked up.

In this manner, the voltage stored across the capacitors 65 is determined by instantaneous head position. If the video heads are early, the ramp is sampled at a higher amplitude and the voltage across the capacitor 65 increases. This, in turn, will result in increased braking current generated by a power amplifier 66 which includes transistors 67, 68 and 69 and which is connected to the sampling hold gate 64.

In the recording mode of the illustrated equipment, vertical sync signals derived from the video signal being recorded is applied via an input terminal 71 to trigger the multivibrator 56 of the ramp generator.

In the playback mode, the servo system reaches equilibrium when the video heads 13 and 14 track precisely over the prerecorded tracks 21 on the tape 15.

In the operation of the system, an amplifier 73 amplifies the delayed head position pulse to drive the sampling hold gate 64. The transistors 67 and 68 are connected in a Darlington configuration to prevent loading of the sampling hold capacitor 65. The transistor 69 provides the brake current.

The brake 31 may operate as a squirrel cage motor with a stationary field. An increase in the braking current acts to brake the rotor that is secured to the shaft of the rotory head drum assembly.

The pulses generated by the head position pickup 28 are amplified at 75 and are applied to a pair of delay multivibrators 76 and 77. The multivibrator 77 is set to place the delayed head position pulse at the correct position on the sampling ramp.

The latter position is adjusted with the aid of a variable resistor 81 which receives a variable voltage signal va a lead 82. The voltage of the latter signal is determined by a closed loop system that acts to integrate jitter in the playback control track pulses due to residual vow and flutter in the tape transport.

To this effect, a pulse is derived from the multivibrator 77 by a lead 83 and is integrated by a resistor 84 and a capacitor 85. The integrated pulse is applied as a steep ramp to a sampling hold gate 86. This gate is switched on by the control track pulse found at the input of the multivibrator 57.

In consequence, a capacitor 87 is charged and stores a direct-current signal proportional to control track pulse jitter. The capacitor 87 is quite large so that the jitter component is integrated over a long time interval.

The voltage across the capacitor 87 is buffered at 88 to control the delay of the head position indicating pulses in the multivibrator 77 via the lead 82. The requisite sampling hold pulse is amplified at 89.

In this manner, head position indicating pulses are delayed to coincide with the average position of the control track pulses and the effects of rapid jitter are minimized.

The head position pickup 29 is mounted 180.degree. from the pickup 28 and serves to generate a pulse as the video head 14 enters the tape path. This pulse may be used in a conventional manner to trigger head switching equipment (not shown) and to generate the blanking pulse for a conventional dropout compensator (not shown).

To this end, the output of the pulse amplifier 91 is applied by a lead 92 to a delay and dropout compensator multivibrator 93 which controls video head switching and, at an output 94, generates a 60 Hz blanking pulse that disables the dropout compensator during the head switching interval. It will be noted that a lead 96 applies pulses derived from the pickup 28 to a second input of the multivibrator 93.

During recording, control signal pulses derived via a lead 98 are amplified by a recording amplifier 99 and are applied via the terminals 41 and 43 and jumper 42 to the control signal recording head 24 for magnetic recording in the control track 23 on the tape 15.

By way of example, in a servo system of the type so far described, control pulses 100 schematically shown in FIG. 4 are recorded in the track 23 at 33 ms intervals. Upon playback, the servo system needs the control pulses conforming to this standard in order to control the reproduction of the video information or signal from the tape 15 in a manner known per se.

A representative waveform illustrating the conventionally recorded and played back control signal pulses 100 is shown in FIG. 9a.

If several of the control pulses 100 are missing from the played back control signal, so that longer intervals occur between succeeding control pulses, conventional servo systems, such as the system described so far with reference to FIGS. 2 and 3, are not capable of controlling the reproduction of the video signal from the tape 15. Accordingly, the prior art always has carefully avoided any dropout of control signal pulses in the control signal as recorded and played back.

By fundamental contrast, the subject invention, for the purposes herein disclosed employs control signals which the prior art would have rejected as substandard.

According to the illustrated preferred embodiment of the subject invention, the jumper 42 shown in FIG. 2 is removed and the encoder shown in FIGS. 5 and 6 is inserted therefor during recording of the control signals by the control head 24.

As shown in FIG. 5, the encoder has an input terminal 102 connected to the terminal 43 shown also in FIG. 2. As shown in FIG. 6, the encoder has an output terminal 103 connected to the terminal 41 which, as shown in FIG. 2, is connected to the control signal recording head 24.

The input terminal of the encoder receives the control signal pulses 100 as generated by the servo system shown in FIGS. 2 and 3 and as amplified by the recording amplifier 99.

Pulse amplifiers 104 and 105 apply the control signal pulses 100 to an inverter 106 and an input 107 of a binary register 108.

The inverter 106 applies its output signal to the B input of a monostable multivibrator 110 to trigger the multivibrator into its time period and to lock out further input pulses during that time period.

The multivibrator 110 generates at its Q output a pulse whose duration corresponds to the prolonged pulse intervals that are desired in the generated substandard control signal. This pulse is applied to the B input of a monostable multivibrator 112 which generates a pulse of a given duration which typically is several times shorter than the duration of the pulse generated by the multivibrator 110.

The Q output pulse of the multivibrator 110 is also applied to the B input of a multivibrator 113 which, at its Q output, generates a narrow strobe pulse which is employed to clock the D-type edge-triggered flip-flop elements 115, 116 and 117 of the binary register 108.

The D inputs of the flip-flop elements 115 to 117 are connected by way of switches 121, 122 and 123 to the register input 107 to receive the generated and amplified control pulses 100.

More specifically, the switches 121 to 123 are double-throw switches which, in one position, connect the associated D input of the particular flip-flop to a positive potential and, in their other position, connect such D input to the pulse amplifier 105 which provides the generated and amplified control pulses 100.

The flip-flop elements 115, 116 and 117 generate one, two or four pulses for each strobe pulse depending on whether the switch 121, 122 or 123 is in a position to connect the corresponding flip-flop element to the input 107. Combinations of generated pulses may be provided by combining any two or all three switches 121 to 123.

The Q and Q outputs of the flip-flop elements 115 to 117 of the binary register 108 shown in FIG. 5 are connected to inputs of NAND elements 125 to 130 of a comparator 131. Other inputs of the NAND elements 125 to 130 of the comparator 131 are connected to a pulse counter 132 also shown in FIG. 6. A line 134 connects the Q output of the multivibrator 112 of the clock input of a J-K master-slave flip-flop element 135 of the pulse counter 132. Further J-K flip-flop elements 136 and 137 of the pulse counter 132 are clocked by the Q output of the preceding flip-flop element. The flip-flop elements 135 to 137 of the pulse counter 132 are cleared by the trailing edge of the Q output pulse of the multivibrator 110. That trailing edge also presets the flip-flop elements 115 to 117 of the binary register 108.

Q and Q outputs of the flip-flop elements 135 to 137 are connected to the NAND elements 125 to 130 of the comparator 131, as shown in FIG. 6. This comparator further includes three inverters 141, 142, and 143 connected to outputs of the NAND element 125 and 126, 127 and 128, and 129 and 130, respectively.

An inverter 145 has an input connected to the outputs of the inverters 141 to 143, and an output connected to an input of a NAND element 146. The other input of the NAND element 146 is connected to the Q output of a monostable multivibrator 148.

The multivibrator 148 has its B input connected to a source of positive potential, and its A.sub.1 and A.sub.2 inputs to the Q output of the multivibrator 112. The Q output of that multivibrator is connected via pulse shaper and voltage level amplifiers 151 and 152 to the output of the encoder shown in FIGS. 5 and 6 and hence to the terminal 41 shown in FIG. 2 at the control signal recording and playback head 24.

The playback amplifier 99 shown in FIG. 2 will apply a video head position indicating pulse 100 (see FIG. 9a) generated in the manner described above with reference to FIGS. 2 and 3, or generated in another conventional manner, to the terminal 43 and hence to the encoder input terminal 102 shown in FIG. 5. That pulse signal will be applied via the pulse amplifiers 104 and 105 to the input 107 of the binary register 108 and, further to the inverter 106 and to the B input of the multivibrator 110.

In response to such pulse, the binary register 108 will provide the comparator 131 with one or more pulses, the number of which is determined by the setting of the switches 121 to 123.

Further pulses 100 generated by the servo system and occurring during the time period of the multivibrator 110 are locked out by the multivibrator 110 and will thus not reach the output 103 of the encoder or otherwise influence its operation. The rising edge of the Q output pulse generated by the multivibrator 110 triggers the multivibrator 112 into generating output pulses which are applied via the lead 134 to the pulse counter 132. This pulse counter counts the pulses generated by the multivibrator 112.

The comparator 131 compares the pulses provided by the binary register 108 and the pulses counted by the pulse counter 132. Upon the determination of an identity of these two sets of pulses, the output of the NAND element 146 inhibits further generation of pulses by the multivibrator 112, provided the Q output of the multivibrator 148 permits such an inhibition at that time.

The pulses thus generated by the encoder shown in FIGS. 5 and 6 are illustrated at 154 in FIG. 9b. After the latter inhibition of the multivibrator 112 by the comparator 131, no further pulses will be provided at the encoder output 103 until the particular time period of the multivibrator 110 has expired. At that instant, the primary register 108 is preset and the pulse counter 132 is cleared by the trailing edge of the Q output pulse of the multivibrator 110.

The first video head position indicating pulse 100 occurring after the latter event will again trigger the multivibrator 110 and will repeat the pulse generating cycle just described with reference to FIGS. 5 and 6. A second series of pulses 154 is then generated by the encoder, as also indicated in FIG. 9b.

As mentioned above, the encoder shown in FIGS. 5 and 6 is connected between the terminals 43 and 41 in lieu of the jumper 42 in the servo system shown in FIGS. 2 and 3. In consequence, the control signal recording head 24 will not record the video head position indicating pulses 100 in the recording track 23 of the tape 15, but rather the substitute pulses 154, as indicated in a section of FIG. 4.

Within the intended scope of the subject invention, only one pulse 154 need be recorded in the control track 23 for each of the pulses 100 which is able to trigger the multivibrator 110 shown in FIG. 5. However, in accordance with a preferred embodiment of the subject invention, two or more pulses 154 are recorded in response to each such pulse 100. In practice, this helps to conceal the nature of the pulses 154, since it will give an unauthorized user or intended duplicator of the video recording the impression that he will need to build a control that responds to the several pulses 154 in the same group. In addition, the number of pulses 154 generated in each pulse group may be varied by changing the setting of the switches 121 to 123 shown in FIG. 5, whereby to provide for an identification of various tape recordings. Moreover, the several pulses 154 in each set of pulses 154 may be employed to help confuse the servo control of unauthorized playback equipment. For this purpose, the pulses 154 may be spaced differently than the pulses 100.

Of course, the subject invention does not exclude the utilization of all of the pulses in each group of pulses 154 in the control of the reproduction of the video recording from the tape 15.

The substitute control signals 154 are picked up by the control signal recording and playback head 24 upon playback of the tape 15 in the machine illustrated in FIG. 1. If the servo control of the playback apparatus is of a conventional type, it will not be able to control the playback of the video recording with the pulses 154. Rather, the servo control will drift off and provide either a garbled playback or, more typically, no displayable playback of the video signal at all. In this manner, unauthorized reproduction and/or unauthorized copying of the video recordings are inhibited, and further theft of video recordings is severely discouraged if not practically excluded in most instances.

Authorized duplication of the video recordings is, however, made possible by the techniques and equipment of the subject invention.

A decoder for regenerating the video head position indicating pulses 100 from the substitute pulses 154 played back by the control track head 24 is shown in FIGS. 7 and 8.

The decoder of FIGS. 7 and 8 is connected between the terminals 51 and 53 of the servo control shown in FIGS. 2 and 3 in lieu of the jumper 52. In particular, the decoder has an input terminal 161 connected to the output terminal 51 of the playback amplifier 45, so as to receive the played back substitute signals 154 from the control track 23 of the tape 15.

These played-back substitute control signals are applied to an input of a NOR element 162 which form part of a pulse latch 163.

The latch further includes a NOR element 164 interconnected with the NOR element 162 as shown in FIG. 7. The latch 163 is reset when the energizing power of the equipment is turned on. To this end, the NOR element 164 has a reset input connected to the output of an inverter 166. The input of that inverter is connected to the collector of a transistor 167. The transistor 167 is connected between ground 168 and a power supply line 169, in order to pull the input of the inverter 166 to ground when the power of the equipment has been turned on. To this end, the base of the transistor 167 is connected via a diode 171 to an RC network 172 connected between ground 168 and power lead 169 in order to introduce a predetermined delay in the operation of the transistor 167. A terminal 173 connects the power lead 169 to a source of direct-current power (not shown). A filter capacitor 174 is connected between the power lead 169 and ground. A terminal 176 connects the power lead 169 to the equipment to be energized in a conventional manner.

In response to a played-back substitute control pulse 154, the latch 163 triggers a monostable multivibrator 177 via a line 178. The multivibrator 177 and a multivibrator 179 are connected back to back and form a clock generator 181.

The latch 163 works only on the first pulse 154 of a group or cluster of played-back substitute control pulses. Accordingly, subsequent pulses in the same series or cluster are ignored by the decoder according to the illustrated preferred embodiment of the invention.

A line 182 applies the output of the clock 181 to the clock input of a J-K master-slave flip-flop element 183 which, together with other J-K flip-flop elements 184, 185 and 186, forms a clock divider counter 187.

Each of the flip-flop elements 184 to 186 has its clock input connected to the Q output of the preceding flip-flop elements.

In the illustrated preferred embodiment, the clock divider counter 187 applies an output pulse to the B input of a monostable multivibrator 189. This presupposes that there are eight clock pulse periods between the leading edge of a head position identifying pulse 100 coinciding with the first pulse 154' of a cluster of pulses 154 and the leading edge of the next pulse 100 coinciding with the first pulse 154' of the next cluster of pulses 154.

When the multivibrator 189 has been triggered by the Q output of the flip-flop element 186, it provides a clock signal via a line 191 to the clock input of a J-K master-slave flip-flop element 192. The flip-flop element 192 and further J-K flip-flop elements 193 and 194 provide a pseudo pulse counter 196.

From the point of view of the decoder, the pulses required to provide all the omitted pulses 100 from the position indicating signal are viewed as pseudo pulses, since they are, in accordance with the subject invention, not recorded in the control track, but have to be reconstructed upon playback from the recorded and reproduced substitute control pulses 154 or at least from predetermined ones of these substitute control pulses.

A NAND element 198 is connected to the flip-flop elements 192 to 194 of the pseudo pulse counter 196, in order to determine when the requisite number of pseudo head position indicating pulses has been regenerated by the decoder.

At that instant, the NAND element 198 provides in a line 199 a reset signal for the latch 163. Accordingly, the next arriving played-back substitute control pulse 154 is able to start a further pseudo pulse generation cycle, which proceeds in the same manner as the cycle just disclosed.

Clear signals for the flip-flop elements 192 to 194 are derived by a line 200 from the output of the NOR element 162 in the latch 163. These clear signals are applied to an input of a NOR element 201, the other input of which is connected to the Q output of the multivibrator 189. A clear signal for the flip-flop elements 183 to 186 is derived by an inverter 203 from the output of the NOR element 201.

As indicated above, the multivibrator 189 generates a pseudo pulse for each eight periods of the clock signal generated at 181.

A line 206 connects the Q output of the multivibrator 189 to the B input of a monostable multivibrator 207 employed for time period shaping purposes. Depending on the requisite phase of the reproduced head position pulses, either the Q output or the Q output of the multivibrator 207 is connected to the output 209 of the decoder.

The decoder output 209, in turn, is connected to the terminal 53 of the servo control shown in FIGS. 2 and 3, with the jumper 52 having been removed as mentioned above.

The waveform of the pulses appearing at the terminals 209 and 53 is illustrated in FIG. 9c. This waveform is the same as the waveform of the head position indicating pulses 100 originally generated in the servo system wherefore the pulses of the waveform of FIG, 9c are provided with the same reference numeral as the pulses of the waveform of FIG. 9a.

The reconstructed head position indicating pulses 100 shown in FIG. 9c are applied via the line 54 to the variable delay multivibrator 58 as if they had been played back from the control track 23 in a conventional video tape recording and playback system. The remainder of the operation of the servo control is thus the same as described above with reference to FIGS. 2 and 3.

Tests with prototypes of preferred embodiments of the subject invention have shown excellent performance of the methods and equipment of this invention.

In particular, no degradation or impairment of the recorded and reproduced video signals was noted when the techniques and equipment according to the subject invention were employed. On the other hand, reproduction and display of recorded video information deteriorated materially as head position indicating pulses 100 were omitted from the recorded control signal. Eventually, no video reproduction at al was possible. This typically occurred when some six position indicating pulses 100 were omitted.

Surprisingly, even an omission of that many head position indicating pulses in succession did not render impossible a perfect reproduction of the video information in accordance with the subject invention. This was very surprising, since it could not have been foreseen that severl pseudo pulses generated upon playback by a decoder in response to only one played-back control pulse at a time would be capable of sustaining the operation of the servo system. Rather, prior-art thinking would have indicated that the servo system needs a recording and reproduction of all or nearly all real head position indicating pulses for a perfect operation of the system. However, the subject invention and its practical manifestations disprove such prior-art belief.

Accordingly, the subject invention records the video information and first control information 154 on the recording tape 15. Upon playback, the video heads 13 and 14 and the servo control of FIGS. 2 and 3 reproduce the video information with the aid of second control information 100 (FIG. 9c) for controlling the reproduction of the video information from the recording medium.

The first control information 154 derived from the originally generated head position indicating pulses 100 (FIG. 9a) is rendered incapable as recorded of controlling the reproduction of the video information upon reproduction of the first control information 154. The requisite second control information 100 (FIG. 9c) is provided by reproducing the recorded first control information 154 from the control track 23 of the tape 15 and converting at least part of the reproduced first control information 154 to the second control information 100 (FIG.