Adaptive picture image compression system
US4580162A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 18, 1983 |
| Grant date | Apr 1, 1986 |
| Priority date | — |
| Expiry date | Nov 18, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image compression system wherein the image is arranged in a block 1 of elements which are Hadamard transformed 2 and then quantized 3 into sequences. The DC component is prediction 4 into a DC error prediction term and all the sequences are then encoded 5 into a variable length code depending on the combination of the sequences. The variable length codes are written into a buffer memory 6 at an input bit rate and read therefrom at an output bit rate asynchronously with the writing. A counter 10 keeps track of the amount of unused space in the buffer memory and a quantization characteristic selector 9 uses this amount to determine the quantization level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.