← Back to Patent Explorer
US4538187A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of and circuit arrangement for recording a color video signal

Assignee: US Philips Corp
•
Filing: 1982-09-10
•
Granted: 1985-08-27
•
Expires: 2002-09-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The invention relates to a method of and a circuit arrangement for recording color signals on a video recorder, the polarity of the color-difference signals being inverted in order to reduce noise in the darker colors such as red and blue caused by the tape-head characteristic.

Inventors

  • 👤 Karl H. Rehfeldt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 13:27
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/80; H04N9/81

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 116 words
A method for recording the information contained in a colour video signal, which signal comprises a luminance signal and two alternately transmitted colour-difference signals, on a record carrier, in particular a magnetic tape, by frequency modulation, recording being effected in the range of the falling portion of the frequency-amplitude transmission curve, including recording the colour-difference signals (R-Y) and (B-Y) with negative polarity in such a way that the amplitude values of bright colour such as a yellow, cyan and green are recorded at a higher frequency value and, consequently, at lower values of the frequency-amplitude transmission curve, and darker colours such as purple, red and blue are recorded at higher values of the frequency-amplitude transmission curve.
Claim 2
Independent Claim 116 words
A method for recording the information contained in a colour video signal, which signal comprises a luminance signal and two alternately transmitted colour-difference signals, on a record carrier, in particular a magnetic tape, by frequency modulation, recording being effected in the range of the falling portion of the frequency-amplitude transmission curve, including recording the colour-difference signals (R-Y) and (B-Y) with negative polarity in such a way that the amplitude values of bright colour such as a yellow, cyan and green are recorded at a higher frequency value and, consequently, at lower values of the frequency-amplitude transmission curve, and darker colours such as purple, red and blue are recorded at higher values of the frequency-amplitude transmission curve.
Claim 3
Dependent Claim 37 words
A method as claimed in claim 1, characterized in that before recording the polarity of the colour-difference signals are inverted and, as the case may be, the average value is additionally shifted towards the higher recording frequencies.
Claim 4
Dependent Claim 38 words
A method for reproducing a color signal from the information recorded by the method claimed in claim 1 or 2, including applying the colour-difference signals originating from the record carrier to a dematrixing circuit via a polarity-inverter stage.
Claim 5
Dependent Claim 84 words
A circuit arrangement for use in recording the information contained in a color video signal comprising matrix means for receiving said color video signal and producing in response thereto a luminance signal and two color difference signals, time compression and inverting means receiving said two color difference signals and processing them to produce two inverted time compressed color difference signals and adding means producing a composite signal by combining said luminance signal and said two compressed signals, said composite signal being suitable for recording.
Claim 6
Dependent Claim 84 words
A circuit arrangement for use in recording the information contained in a color video signal comprising matrix means for receiving said color video signal and producing in response thereto a luminance signal and two color difference signals, time compression and inverting means receiving said two color difference signals and processing them to produce two inverted time compressed color difference signals and adding means producing a composite signal by combining said luminance signal and said two compressed signals, said composite signal being suitable for recording.
Claim 7
Dependent Claim 85 words
A circuit arrangement for producing a color video signal from the composite signal produced by the arrangement of claim 4, including separating means receiving said composite signal and separating said luminance signal and said two compressed inverted color difference signals from each other, time expanding and inverting means processing said two inverted time compressed color difference signals and producing therefrom said two color difference signals and the matrixing means combining said luminance signal and said two color difference signals to produce said color video signal.

References Cited (Backward Citations)

US4242699A Cited
US4208671A Cited
US4359756A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-08-26 1989-02-25 1989-08-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-08-26 1993-02-25 1993-08-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-08-26 1997-02-25 1997-08-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag