Apparatus for correcting angular errors in color video signals

Claim 2

Apparatus for correcting effects of angular errors in a chrominance video signal accompanied by a reference signal affected by said angular errors, comprising in combination: means for processing said chrominance video signal including said reference signal to dispose modulation components of said chrominance video signal about a substantially stable carrier while substantially retaining phase and amplitude interrelationships of said modulation components; means connected to said processing means for separating the processed reference signal from the processed chrominance video signal; means connected to said separating means for deriving from said separated processed reference signal an error signal indicative of angular errors in said processed chrominance video signal; and means connected to said processing means for controlling said processing means in response to said error signal to correct effects of said angular errors.

Claim 3

Apparatus as claimed in claim 1, wherein said reference signal comprises color synchronizAtion bursts, and wherein: said signal processing means are constructed to process said chrominance video signal including said color synchronization bursts; said separating means include means for separating the precessed color synchronization bursts from the processed chrominance video signal; and said error signal-deriving means include means for deriving said error signal from said separated processed color synchronization bursts in said processed chrominance video signal.

Claim 4

Apparatus as claimed in claim 1, wherein at least part of each of said signal processing means, said separating means, said error signal-deriving means, and said controlling means are included in phase-lock loop means.

Claim 5

Apparatus as claimed in claim 1, wherein said processing means include modulator means.

Claim 6

Apparatus as claimed in claim 4, wherein said modulator means are of a balanced type.

Claim 7

Apparatus as claimed in claim 1, wherein: said processing means include modulator means driven by a further reference signal; said error signal-deriving means include means for providing a stable signal and means for providing said error signal from a comparison of said separated processed reference signal and said stable signal; and said means for controlling said processing means include phase-controlled reference generator means connected to said modulator means and said error signal-deriving means for providing said further reference signal and for varying the phase of said further reference signal in response to said error signal.

Claim 8

Apparatus for correcting effects of angular errors in a chrominance video signal accompanied by a reference signal affected by said angular errors, comprising phase-lock loop means having input means for receiving said chrominance video signal and said reference signal, and output means, and including in combination: means connected between said input means and said output means for processing said chrominance video signal including said reference signal to dispose modulation components of said chrominance video signal about a substantially stable carrier while substantially retaining phase and amplitude interrelationships of said modulation components; means for applying said processed chrominance video signal to said output means; means connected to said processing means for separating the processed reference signal from the processed chrominance video signal; means connected to said separating means for deriving from said separated processed reference signal an error signal indicative of angular errors in said processed chrominance video signal; and means connected between said error signal-deriving means and said processing means for controlling said processing means in response to said error signal to correct effects of said angular errors.

Claim 9

Apparatus for correcting effects of angular errors in a chrominance video signal accompanied by a reference signal affected by said angular errors, comprising phase-lock loop means having input means for receiving said chrominance video signal and said reference signal, and output means, and including in combination: means connected between said input means and said output means for processing said chrominance video signal including said reference signal to dispose modulation components of said chrominance video signal about a substantially stable carrier while substantially retaining phase and amplitude interrelationships of said modulation components; means for applying said processed chrominance video signal to said output means; means connected to said processing means for separating the processed reference signal from the processed chrominance video signal; means connected to said separating means for deriving from said separated processed reference signal an error signal indicative of angular errors in said processed chrominance video signal; and means connected between said error signal-deriving means and said processing means for controlling said processing means in response to said error signal to correct effects of said angular errors.

Claim 10

Apparatus as claimed in claim 7, wherein said reference signal comprises color synchronization bursts, and wherein: said signal processing means are constructed to process said chrominance video signal including said color synchronization bursts; said error signal-deriving means include means for deriving said error signal from said separated processed color synchronization bursts in said processed chrominance video signal.

Claim 11

Apparatus as claimed in claim 7, wherein: said processing means include modulator means having a modulating signal input connected to said input means, a further input in said phase-lock loop means for a further reference signal, and an output in said phase-lock loop means, and filter means connected between said modulator output and said output means of said phase-lock loop means for extracting said modulation components of said processed radio frequency signal from said modulator output; and said means for controlling said processing means include phase-controlled reference generator means connected to said further modulator input and said error signal-deriving means for providing said further reference signal foR said modulator means and for controlling the phase of said further reference signal in response to said error signal.

Claim 12

Apparatus as claimed in claim 9, wherein said error signal-deriving means include means for providing a stable reference signal, and means connected in said phase-lock loop means between said output means of said phase-lock loop means and said phase-controlled reference signal generator means, and connected to said stable reference signal providing means for detecting phase differences between said separated processed reference signal and said stable reference signal.

Claim 13

Apparatus for correcting effects of angular errors in a video signal including luminance information and chrominance information accompanied by a reference signal affected by said angular errors, comprising in combination: means for deriving from said video signal and said reference signal a first signal component including luminance information within a first frequency spectrum, and a second signal component including chrominance information and luminance information within a second frequency spectrum and including said reference signal; means for processing said second signal component including said reference signal to dispose modulation components including said chrominance information and said luminance information in said second signal component about a substantially stable carrier; means connected to said processing means for separating the processed reference signal from the processed chrominance and luminance information; means connected to said separating means for deriving from said separated processed reference signal an error signal indicative of angular errors in said processed video signal component; means connected to said processing means for controlling said processing means in response to said error signal to correct effects of said angular errors; and means for recombining said first signal component and said processed second signal component into a composite video signal.

Claim 14

Apparatus for correcting effects of angular errors in a video signal including luminance information and chrominance information accompanied by a reference signal affected by said angular errors, comprising in combination: means for deriving from said video signal and said reference signal a first signal component including luminance information within a first frequency spectrum, and a second signal component including chrominance information and luminance information within a second frequency spectrum and including said reference signal; means for processing said second signal component including said reference signal to dispose modulation components including said chrominance information and said luminance information in said second signal component about a substantially stable carrier; means connected to said processing means for separating the processed reference signal from the processed chrominance and luminance information; means connected to said separating means for deriving from said separated processed reference signal an error signal indicative of angular errors in said processed video signal component; means connected to said processing means for controlling said processing means in response to said error signal to correct effects of said angular errors; and means for recombining said first signal component and said processed second signal component into a composite video signal.

Claim 15

Apparatus as claimed in claim 11, including means connected between said processing means and said recombining means for inverting the spectrum of said luminance information in said processed second video signal component.

Claim 16

Apparatus as claimed in claim 11, wherein said reference signal comprises color synchronization bursts, and wherein: said signal component deriving means include means for deriving said first signal component and a second signal component including said chrominance information and luminance information within a second frequency spectrum and including said color synchronization bursts; said signal processing means are constructed to process said second signal component including said color synchronization bursts; said separating means include means for separating the processed color synchronization bursts from the processed chrominance and luminance information; and said error signal-deriving means include means for deriving said error signal from said separated color synchronization bursts.

Claim 17

Apparatus as claimed in claim 11, wherein said separating means are connected to said processing means by way of said recombining means for separating the processed reference signal from said recombined composite video signal.

Claim 18

Apparatus as claimed in claim 12, wherein said reference signal comprises color synchronization bursts, and wherein: said signal component deriving means include means for deriving said first signal component and a second signal component including said chrominance information and luminance information within a second frequency spectrum and including said color synchronization bursts; said signal processing means are constructed to process said second signal component including said color synchronization bursts; said separating means include means connected to said processing means by way of said recombining means for separating the processed color synchronization bursts fRom said recombined composite video signal; and said error signal-deriving means include means for deriving said error signal from said separated color synchronization bursts.

Claim 19

Apparatus as claimed in claim 11, wherein said processing means, said separating means, said error signal-deriving means and said controlling means are connected in a phase-lock loop.

Claim 20

Apparatus as claimed in claim 1, wherein: said error signal-deriving means include means for providing a stable reference signal, and means connected to said separating means and said stable reference signal providing means for deriving said error signal from said separated processed reference signal and from said stable reference signal.

Claim 21

Apparatus as claimed in claim 1, wherein: said error signal-deriving means include means for providing a stable reference signal, means connected to said separating means and said stable reference signal providing means for providing a phase error signal by comparing said separated processed reference signal and said stable reference signal; said controlling means include means connected to said comparing means for providing a further reference signal including a stable frequency component and a variable component varying in phase in response to said phase error signal; and said processing means include means for processing said chrominance video signal including said reference signal with the aid of said further reference signal including said stable frequency component and said variable frequency component.