Interframe coding apparatus
US4047221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1976 |
| Grant date | Sep 6, 1977 |
| Priority date | — |
| Expiry date | Sep 30, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In interframe coding apparatus in which an input signal is encoded by an interframe coder and its output code is written in a buffer memory, and is read out therefrom at a constant bit rate, a variable characteristics comb filter is provided at a stage preceding the interframe coder. The period of the frequency characteristics of the comb filter is selected to be the frame period of the input signal. By a controller, the occupancy of the buffer memory is detected to control either one or both of the attenuation in the elimination band and high frequency cut-off characteristics of the comb filter detected value to prevent an overflow from the buffer memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.