GB1267267A - - Google Patents
Info
- Publication number
- GB1267267A GB1267267A GB1267267DA GB1267267A GB 1267267 A GB1267267 A GB 1267267A GB 1267267D A GB1267267D A GB 1267267DA GB 1267267 A GB1267267 A GB 1267267A
- Authority
- GB
- United Kingdom
- Prior art keywords
- signal
- circuit
- phase
- component
- sin
- 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.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/44—Colour synchronisation
- H04N9/455—Generation of colour burst signals; Insertion of colour burst signals in colour picture signals or separation of colour burst signals from colour picture signals
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Processing Of Color Television Signals (AREA)
- Color Television Systems (AREA)
Abstract
1,267,267. Colour television. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 27 Jan., 1970 130 Jan., 1969; 8 Aug., 1969; 18 Dec., 1969], No. 3874/70. Heading H4F. In a PAL colour television chrominance signal component demodulator, -to reduce the influence of differential phase error between the subcarrier generated from the separated 'burst signals and the colour information in the chrominance signal, the generated subcarrier is phase corrected in response to a signal derived from the output of the demodulator circuit which contains components which are a measure of the magnitude and direction of the differential phase error. As shown, Fig. 1, the outputs of the chrominance signal synchronous demodulators 37 and 43 are fed via time selection circuits 57 and 59 (see later) and low-pass filters 63, 65 and 67, 69 to a non-linear signal handling circuit 75 (see later), the output of which is fed via a low-pass filter 79, 81 to a phase correction circuit 29 which corrects the phase of the subcarrier from the chrominance subcarrier generator 13, the frequency and phase of which is fixed relative to the mean frequency and phase of the swinging burst signal by means of a control loop including synchronous detector 9 and a D.C./A.C. component separator circuit 17. The outputs of the demodulators 37 and 43 each have a component of constant sign and a component of alternating sign, i.e. (B-Y) cos #Œ(R-Y) sin # and Œ(R-Y) cos # - (B-Y) sin # The sin # component in each signal is proportional to the differential phase error. The components of constant sign are fed to the non- linear handling circuit 75 which either forms the product or the quotient thereof which is used after filtering as the control signal. Time selection circuits 57 and 59 may be provided to ensure that the mean value of the signal is determined only over a portion, e.g. 5-20%, of each line period. These circuits being rendered conducting only during a portion of each line period by means of a pulse derived from a line flyback pulse and delayed by a delay circuit 83 which may -be controlled by a sine or sawtooth generator having a low frequency. A control signal dependent on (R-Y) and not (B-Y) may be derived-by passing both the demodulator outputs first through 180 degrees phase shifters operated by half-line-frequency switching voltages before they -are applied to the non-linear handling circuit. Both control signals may be used simultaneously in which case even when one of (R-Y) or (B-Y) is zero a control signal is formed. A non-linear handling circuit is described with reference to Figs. 2 and 3 (not shown), in which the effect of the polarity of the colour difference signals is nullified, the control signal always comprising - (B-Y sin #. A quotient forming non-linear handling circuit is described with reference to Fig. 4 (not shown) which comprises two logarithmic transfer circuits, the outputs of which are subtracted and passed to an anti-logarithmic transfer circuit and a sign correction circuit.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19691904528 DE1904528B1 (en) | 1969-01-30 | 1969-01-30 | Method and circuit arrangement for color television receivers to compensate for phase errors in a PAL chrominance signal |
DE19691940563 DE1940563C3 (en) | 1969-01-30 | 1969-08-08 | Color television receiver circuitry for compensating for phase deficiencies in a PAL signal |
DE19691963464 DE1963464A1 (en) | 1969-01-30 | 1969-12-18 | Television receiver circuitry to compensate for phase errors |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1267267A true GB1267267A (en) | 1972-03-15 |
Family
ID=27181760
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1267267D Expired GB1267267A (en) | 1969-01-30 | 1970-01-27 |
Country Status (8)
Country | Link |
---|---|
JP (1) | JPS4814611B1 (en) |
BE (1) | BE745184A (en) |
DE (2) | DE1940563C3 (en) |
ES (1) | ES375980A1 (en) |
FR (1) | FR2029720A1 (en) |
GB (1) | GB1267267A (en) |
NL (1) | NL7001029A (en) |
SE (1) | SE348353B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1755347A3 (en) * | 2005-08-17 | 2008-05-28 | SNELL & WILCOX LIMITED | Colour error correction |
-
1969
- 1969-08-08 DE DE19691940563 patent/DE1940563C3/en not_active Expired
- 1969-12-18 DE DE19691963464 patent/DE1963464A1/en active Pending
-
1970
- 1970-01-24 NL NL7001029A patent/NL7001029A/xx unknown
- 1970-01-27 SE SE99670A patent/SE348353B/xx unknown
- 1970-01-27 GB GB1267267D patent/GB1267267A/en not_active Expired
- 1970-01-28 ES ES375980A patent/ES375980A1/en not_active Expired
- 1970-01-29 BE BE745184D patent/BE745184A/en unknown
- 1970-01-30 JP JP806870A patent/JPS4814611B1/ja active Pending
- 1970-01-30 FR FR7003311A patent/FR2029720A1/fr not_active Withdrawn
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1755347A3 (en) * | 2005-08-17 | 2008-05-28 | SNELL & WILCOX LIMITED | Colour error correction |
Also Published As
Publication number | Publication date |
---|---|
SE348353B (en) | 1972-08-28 |
NL7001029A (en) | 1970-08-03 |
BE745184A (en) | 1970-07-29 |
DE1940563A1 (en) | 1971-02-11 |
FR2029720A1 (en) | 1970-10-23 |
DE1940563B2 (en) | 1978-03-30 |
JPS4814611B1 (en) | 1973-05-09 |
DE1940563C3 (en) | 1978-11-30 |
ES375980A1 (en) | 1972-06-16 |
DE1963464A1 (en) | 1971-07-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1436877A (en) | Video colour signal recovery | |
JPS56109087A (en) | Digital color encoder | |
GB1361274A (en) | Selective tint correction circuits | |
GB1435954A (en) | Compatible stereoscopic colouer television system | |
GB1267267A (en) | ||
US4000511A (en) | Device for the compensation of drop-outs in a angle-velocity modulated signal | |
US3688019A (en) | Demodulator circuit for color television-receiver | |
CA1241435A (en) | Television receiver including a circuit arrangement for demodulating an ntsc-coded colour signal | |
ES391550A1 (en) | Chroma processing circuitry with selectable color correction mode | |
US2830112A (en) | Color television | |
US2734939A (en) | Color television | |
CA1239198A (en) | Am synchronous detecting circuit | |
US4549143A (en) | F.M. Demodulator with waveform correction circuit | |
US3761606A (en) | Color television receiver for use in pal system | |
JPS5912075B2 (en) | Method for generating switching information based on hue position from encoded color video signal | |
US4101940A (en) | Circuit for delaying a composite video signal by a line duration, particularly for use with a video record player | |
GB1220550A (en) | Pal identification circuit | |
EP0399758B1 (en) | FM-demodulating apparatus | |
US5132782A (en) | Interleave detector of composite video signal | |
GB1359192A (en) | Tint correction circuits | |
JPS5816393B2 (en) | color television simulator | |
GB1141752A (en) | Colour television transmitting apparatus | |
GB1077946A (en) | Improvements in and relating to special effects apparatus for television | |
JPS63309088A (en) | Acc circuit for digital color television receiver | |
JPH01221091A (en) | Digital hue adjusting circuit |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |