Apparatus for recording a video signal sampled at frequency f.sub.s and reproducing the video signal as a signal essentially sampled at frequency 2f.sub.s
US4682250A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 13, 1984 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Jun 13, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/797
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal recording and reproducing apparatus comprises a first sampling circuit for sampling a recording video signal which has a band with an upper limit frequency f.sub.a and is to be recorded by a sampling signal having a frequency f.sub.s, where the frequencies f.sub.a and f.sub.s satisfying a relation f.sub.a <f.sub.s <2f.sub.a and an equation f.sub.s =(2n+1)f.sub.H /2, n is an integer, and f.sub.H is a horizontal scanning frequency of the recording video signal, a recording and reproducing circuit for recording an output signal of the first sampling circuit on a recording medium and for reproducing the signal from the recording medium, a delay circuit for delaying the signal which is reproduced from the recording medium by the recording and reproducing circuit by a delay time of one horizontal scanning period, a second sampling circuit for alternately sampling input and output signals of the delay circuit by a sampling signal having the frequency f.sub.s, and an adding circuit for adding alternately sampled signals from the second sampling circuit, and for obtaining a reproduced output signal which has essentially been sampled at a frequency of 2f.sub.s.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.