Modularized architecture for rendering scaled discrete cosine transform coefficients and inverse thereof for rapid implementation
US5649077A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1996 |
| Grant date | Jul 15, 1997 |
| Priority date | — |
| Expiry date | Apr 15, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T9/007
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention describes a circuit for performing high speed forward Scaled Discrete Cosine Transform (SDCT) and inverse Scaled Discrete Cosine Transform (ISDCT) in pipeline architecture which is ideally, but not exclusively, used for compressing and decompressing large volume image data in real time. A high throughput of image data transform and inverse transform is achieved with a relatively slow internal clock. The four stage pipeline architecture of the present invention requires no more than five multipliers in rendering either the forward SDCT or inverse SDCT coefficients. The lower-order SDCT's for either the forward or the inverse direction are imbedded in the higher-order forward SDCT or inverse SDCT respectively. By taking advantage of the recursive properties of the SDCT's, a larger size SDCT can be always implemented by using a combination of variants of smaller size SDCT. The scaling effects of the coefficients is restored as the compressed image data undergoes the inverse quantization stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.