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US5206907A Expired / Lapsed US ⏱️ 0.0 years remaining

Television signal scrambling method and apparatus

Assignee: Pioneer Corp
•
Filing: 1991-04-30
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Granted: 1993-04-27
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Expires: 2011-04-30
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Abstract

Abstract A video signal from a video-audio source is converted to a digital signal, and stored in a memory. A read clock or a write clock for the memory is temporarily suspended to elongate or shorten a corresponding part of the digital signal. The elongated/shortened digital signal is converted to an analog video signal; and finally sync/blanking signal portions are compressed by a predetermined amount. The elongating operation may be continued and a one horizontal period part of the digital signal may be deleted when an accumulated elongation time has reached or exceeded one horizontal period.

Inventors

  • 👤 Takashi Hashimoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 00:16
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/167; H04N7/169

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 148 words
A scrambling apparatus of a television signal including a video signal and an audio signal, comprising: analog-to-digital conversion means for converting a first video signal to a digital signal; memory means for storing the digital signal; timing generating means for providing a write clock and a read clock to the memory means to write the digital signal to and read the digital signal from the memory means, the provision of the read clock or write clock being temporarily suspended so that a corresponding part of the read-out digital signal is elongated or shortened, respectively, to change the length of a line of the video signal; digital-to-analog conversion means for converting the digital signal output from the memory means to a second video signal; and scrambling means for compressing a horizontal sync signal portion and/or a vertical blanking interval portion of the second video signal by a predetermined amount.
Claim 2
Dependent Claim 148 words
A scrambling apparatus of a television signal including a video signal and an audio signal, comprising: analog-to-digital conversion means for converting a first video signal to a digital signal; memory means for storing the digital signal; timing generating means for providing a write clock and a read clock to the memory means to write the digital signal to and read the digital signal from the memory means, the provision of the read clock or write clock being temporarily suspended so that a corresponding part of the read-out digital signal is elongated or shortened, respectively, to change the length of a line of the video signal; digital-to-analog conversion means for converting the digital signal output from the memory means to a second video signal; and scrambling means for compressing a horizontal sync signal portion and/or a vertical blanking interval portion of the second video signal by a predetermined amount.
Claim 3
Dependent Claim 48 words
The apparatus according to claim 1, wherein the part of the read-out digital signal is elongated or shortened with a unit period longer than one field length, said unit period being a repetition period in which an accumulated elongation time returns to zero or reaches a one-line period.
Claim 4
Dependent Claim 21 words
The apparatus according to claim 2, wherein a temporary suspension time of the write and read clocks is varied with time.
Claim 5
Dependent Claim 21 words
The apparatus according to claim 1, wherein the part of the read-out digital signal is elongated/shortened according to a predetermined pattern.
Claim 6
Dependent Claim 42 words
The apparatus according to claim 1, wherein the part of the read-out digital signal continues to be elongated, and a one horizontal period part of the digital signal is deleted when an accumulated elongation time has reached or exceeded one horizontal period.
Claim 7
Dependent Claim 22 words
The apparatus according to claim 5, wherein the accumulated elongation time is made substantially zero every integer multiple of the field length.
Claim 8
Dependent Claim 29 words
The apparatus according to claim 5, wherein a temporary suspension time of the write and read clocks is an integer multiple of the period of the color burst signal.
Claim 9
Dependent Claim 14 words
The apparatus according to claim 5, wherein the memory means is a two-line memory.
Claim 10
Dependent Claim 47 words
The apparatus according to claim 1, wherein the scrambling means further superposing on the audio signal a key signal at a position corresponding to the horizontal sync signal portion and timing mode data indicating a positional relationship between the horizontal sync signal portion and the key signal.
Claim 11
Independent Claim 77 words
A method for scrambling a television signal including a video signal and an audio signal, comprising the steps of: converting a first video signal to a digital signal; elongating/shortening a part of the digital signal to change the length of a line of the video signal; converting the elongated/shortened digital signal to a second video signal; compressing a horizontal sync signal portion and/or a vertical blanking interval portion of the second video signal by a predetermined amount.
Claim 12
Independent Claim 77 words
A method for scrambling a television signal including a video signal and an audio signal, comprising the steps of: converting a first video signal to a digital signal; elongating/shortening a part of the digital signal to change the length of a line of the video signal; converting the elongated/shortened digital signal to a second video signal; compressing a horizontal sync signal portion and/or a vertical blanking interval portion of the second video signal by a predetermined amount.
Claim 13
Dependent Claim 36 words
The method according to claim 10, wherein the part of the digital signal is elongated or shortened by temporarily suspending a read operation or a write operation on a memory for storing the digital signal, respectively.
Claim 14
Dependent Claim 47 words
The method according to claim 10, wherein the part of the digital signal is elongated or shortened with a unit period longer than one field length, said unit period being a repetition period in which an accumulated elongation time returns to zero or reaches a one-line period.
Claim 15
Dependent Claim 21 words
The method according to claim 12, wherein a temporary suspension time of the write and read clocks is varied with time.
Claim 16
Dependent Claim 20 words
The method according to claim 10, wherein the part of the digital signal is elongated/shortened according to a predetermined pattern.
Claim 17
Dependent Claim 41 words
The method according to claim 10, wherein the part of the digital signal continues to be elongated, and a one horizontal period part of the digital signal is deleted when an accumulated elongation time has reached or exceeded one horizontal period.
Claim 18
Dependent Claim 22 words
The method according to claim 15, wherein the accumulated elongation time is made substantially zero every integer multiple of the field length.
Claim 19
Dependent Claim 29 words
The method according to claim 15, wherein a temporary suspension time of the write and read clocks is an integer multiple of the period of the color burst signal.

References Cited (Backward Citations)

US4901349A Cited
US5034981A Cited
US5058157A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-04-26 1996-10-26 1997-04-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-04-26 2000-10-26 2001-04-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-04-26 2004-10-26 2005-04-27 $7700.00 Window Closed / Lapsed

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