CN1063984A - The guard method of copyright of video tape and device - Google Patents
The guard method of copyright of video tape and device Download PDFInfo
- Publication number
- CN1063984A CN1063984A CN 91100781 CN91100781A CN1063984A CN 1063984 A CN1063984 A CN 1063984A CN 91100781 CN91100781 CN 91100781 CN 91100781 A CN91100781 A CN 91100781A CN 1063984 A CN1063984 A CN 1063984A
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- CN
- China
- Prior art keywords
- signal
- video tape
- videotape
- microprocessor
- recorded
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 11
- 239000013078 crystal Substances 0.000 claims 1
- 239000010453 quartz Substances 0.000 claims 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims 1
- 230000000694 effects Effects 0.000 description 4
- 230000003534 oscillatory effect Effects 0.000 description 2
- 241000406668 Loxodonta cyclotis Species 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
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- Television Signal Processing For Recording (AREA)
Abstract
The present invention relates to guard method and device that a kind of copyright that prevents videotape is invaded.When recording videotape; the device of being made up of microprocessor, sync separator, triple gate buffer and clock reference element goes round and begins again in field preface of the vision signal of being recorded is spaced apart 8,4,2,1 field blanking and exports a random signal; record amplifier output through video tape recorder; be recorded on the tape by write head; when videotape is replicated; duplicated subband can't be reset, and reaches the purpose of practical protection copyright.
Description
The present invention relates to guard method and device that a kind of copyright that prevents videotape is invaded.
The making of videotape often relates to the protection problem of copyright; at present; it still is not enough that copyright protection relies on the Copyright Law merely; be necessary the protection of taking suitable technological means practical in addition to the copyright of videotape; invaded with the copyright that really prevents videotape, realized that all rights reserved, the random effect of pirate recordings.The present invention develops a kind of guard method and device that prevents that copyright of video tape from being invaded according to the principle of video tape recorder recording playback elephant.
The present invention adds a random signal when recording videotape in the field synchronization blanking interval of vision signal, make the videotape pirate recordings after, the tape of newly recording can't be reset, and reaches the purpose of protection copyright.
Parts-servo system that one key is arranged in video recorder system, the precision of this system is very high, directly has influence on the quality of the record and replay of vision signal.But the source of this system its reference signal when record and replay is inequality.When record, reference signal is from the field sync signal in the quilt vision signal of recording; And at playback time, reference signal is but from the oscillatory system of video tape recorder itself.The present invention utilizes this difference creation and comes out.
The Copyright Protection principal contradiction of videotape is aspect record; when therefore the present invention records videotape exactly to the guard method of copyright; in the vertical blanking period of the vision signal of being recorded, add a random signal; promptly not in the vertical blanking period of each, all to add, add but be interrupted aperiodically.Certainly; it is best that field preface by 8,4,2,1 adds effect at interval; promptly be in the vertical blanking period of the 8th vision signal, to add a random signal; add one again every four vision signals, again every one of two adding, add one again later on every one; so go round and begin again; the random signal that is added can be used square wave, and this signal is called copyright protection signal, and it is recorded in the video master tape.
General video tape recorder is from the field sync signal of being recorded in the servo reference signal of recording state lower drum; when the people wants copying magnetic tapes; owing to have the copyright protection random signal in the master tape, the reference signal that makes video tape recorder under the recording state give servo system becomes not benchmark.But, can make effect not too obvious because the inertia of magnetic drum has the ability of opposing enchancement factor.In order to enlarge this effect, add by 8,4,2,1 relation, will make the magnetic drum rotating speed produce shake.Under the normal situation of tape running, make the video track that is recorded on the tape different in size, each is variant.Under playback mode, reference signal comes from the oscillatory system of video tape recorder itself, and the subband after recording carries out playback time, and the capable field frequencies range of outputting video signal changes, and it is seriously asynchronous that television set is produced, and can't watch.Even therefore master tape is replicated, there have not been much meanings yet, copyright of video tape is protected conscientiously.
Implement device of the present invention and method of attachment as shown in Figure 1, wherein be the connection layout of equipment therefor of the present invention in the frame of broken lines.In Fig. 1,1 is the vision signal input, can be taken from video tape recorder the input of vision signal jack by recording video signal, also can take from the inner separated in synchronization output of video tape recorder; 2 is the video tape recorder recording channel; 3 are video tape recorder record output amplifier; 4 is write head.In dashed rectangle, the used device of this method comprises microprocessor 5 and ancillary equipment-sync separator 6, triple gate buffer 7 and clock reference element 9, and the switch pulse 10 of 25Hz magnetic head can be from the servo system output pulse of video tape recorder, its decline
Must cause that microprocessor interrupts,, magnetic head be switched light relation computing time so that field system chronizing impulse cooperates with the 25Hz pulse; CTL recording playback control signal 11 can be implemented the recording playback conversion to this device from system's control output of video tape recorder, makes system unsettled when not inserting copyright protection signal; CTL signal 12 during record offers microprocessor 5 by the output of video tape recorder record, makes it judge odd field and even field relation.Enter microprocessor 5 from video input 1 synchronizing signal that obtains through sync separator 6; time identification signal as the copyright protection signal adding; produce by microprocessor 5 in 8,4,2,1 the vertical blanking period at interval and the copyright protection signal 8 of output enters the input of the record output amplifier of video tape recorder through the triple gate buffer in recording process midfield preface, again through write head typing tape.
Claims (3)
1, a kind of guard method of copyright of video tape adds a random signal in the vertical blanking period of the vision signal that is recorded when it is characterized in that recording videotape, and by the field preface that is recorded vision signal 8,4,2,1 adding that goes round and begins again at interval.
2, the used device of a kind of copyright of video tape guard method as claimed in claim 1; it is characterized in that this device is made up of microprocessor 5 and ancillary equipment-sync separator 6, triple gate buffer 7 and clock reference element 9; CTL signal 12 can offer microprocessor 5 by video tape recorder when 25Hz magnetic head switch pulse 10, CTL recording playback control signal 11, record, and the copyright protection signal 8 that is produced and exported by microprocessor 5 enters the input that video tape recorder writes down output amplifier 3 through triple gate buffer 7.
3, a kind of device as claimed in claim 2 is characterized in that the clock reference element can adopt the quartz crystal component of 6MHz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 91100781 CN1063984A (en) | 1991-02-04 | 1991-02-04 | The guard method of copyright of video tape and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 91100781 CN1063984A (en) | 1991-02-04 | 1991-02-04 | The guard method of copyright of video tape and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1063984A true CN1063984A (en) | 1992-08-26 |
Family
ID=4904810
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 91100781 Pending CN1063984A (en) | 1991-02-04 | 1991-02-04 | The guard method of copyright of video tape and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1063984A (en) |
-
1991
- 1991-02-04 CN CN 91100781 patent/CN1063984A/en active Pending
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C01 | Deemed withdrawal of patent application (patent law 1993) | ||
| WD01 | Invention patent application deemed withdrawn after publication |