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US4707737A Expired / Lapsed US ⏱️ 0.0 years remaining

Band compression apparatus for a video signal

Assignee: Mitsubishi Electric Corp
•
Filing: 1986-07-09
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Granted: 1987-11-17
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Expires: 2006-07-09
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Abstract

Abstract A band compression apparatus for transmitting a video signal having three color component signals sampled at a sampling frequency of 2Fs and a gradation of N bits per picture element by a transmission path of a gradation of N bits per sample and a sample transmission frequency 2Fs includes a prefilter for restricting the band of each color component signal; a sub-sample circuit for compressing the respective band restricted color component signal to a sampling frequency Fs; a signal separation switching circuit for separating data of 3n bits comprising the upper n bits of the sub-sampled color component signals 3n=2N+k (k<N) into two main signals as transmission samples of N bits and a fraction signal of k bits; a fraction signal storage RAM for storing one line video signal portions of said fraction signal; and a signal outputting switching circuit for outputting said stored fraction signal to the transmission path by time compressing the same into a signal of N bits as a first transmission sample during the horizontal blanking period of the video signal, or outputting said sub-sampled signal of N bits as a second transmission sample during the video signal period.

Inventors

  • 👤 Mitsunori Adachi
  • 👤 Satoru Tomita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 13:20
CPC Classifications
H; H04; H04N; H04N11/00; H04N11/04; H04N11/042; H04N11/048

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 193 words
A band compression apparatus for transmitting a video signal comprising three color component signals sampled at a sampling frequency of 2Fs and a gradation of N bits per picture element, through a transmission path of a gradation of N bits per sample and a sample transmission frequency of 2Fs comprising: a prefilter for restricting the band of each color component signal; sub-sampling means for compressing the respective band restricted color component signal to a sampling frequency Fs; signal separation means for separating data of 3n bits comprising the upper n bits of the sub-sampled color component signals 3n=2N+k (k<N) into two main signals as transmission samples of N bits and a fraction signal of k bits; fraction signal storage means for storing one line video signal portions of said fraction signal; and signal outputting means for outputting said stored fraction signal to the transmission path by time compressing said fraction signal into a signal of N bits as a first transmission sample during a horizontal blanking period of the video signal, or outputting said sub-sampled signal of N bits as a second transmission sample during the video signal period of the video signal.
Claim 2
Dependent Claim 193 words
A band compression apparatus for transmitting a video signal comprising three color component signals sampled at a sampling frequency of 2Fs and a gradation of N bits per picture element, through a transmission path of a gradation of N bits per sample and a sample transmission frequency of 2Fs comprising: a prefilter for restricting the band of each color component signal; sub-sampling means for compressing the respective band restricted color component signal to a sampling frequency Fs; signal separation means for separating data of 3n bits comprising the upper n bits of the sub-sampled color component signals 3n=2N+k (k<N) into two main signals as transmission samples of N bits and a fraction signal of k bits; fraction signal storage means for storing one line video signal portions of said fraction signal; and signal outputting means for outputting said stored fraction signal to the transmission path by time compressing said fraction signal into a signal of N bits as a first transmission sample during a horizontal blanking period of the video signal, or outputting said sub-sampled signal of N bits as a second transmission sample during the video signal period of the video signal.
Claim 3
Dependent Claim 26 words
The apparatus defined in claim 1, wherein said sub-sampling means comprises a latch for sub-sampling the band restricted color component signals at a frequency of Fs.
Claim 4
Dependent Claim 42 words
The apparatus defined in claim 2, wherein said signal separation means comprises a switch for switching the sub-sampled color component signals from the latch into two signals of an N bit color component signal and a k bit fractional color component signal.
Claim 5
Dependent Claim 15 words
The apparatus defined in claim 1, wherein said fraction signal storage means comprises a RAM.

References Cited (Backward Citations)

US4323916A Cited
US4396937A Cited
US4589110A Cited
US4468708A Cited
US4602333A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-16 1991-05-18 1991-11-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-16 1995-05-18 1995-11-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-16 1999-05-18 1999-11-17 $7700.00 Window Closed / Lapsed

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