Method and apparatus for prestoring dequantization information for DCT VLC decoding
US5784494A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 1995 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | Apr 18, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A DCT VLC decoding method substantially lessens the computational burden of picture dequantization. The method of decoding variable length code (VLC) data includes the step of receiving a bitstream sequence organized into a hierarchy of levels including, in order, a sequence layer, a group of pictures layer, a picture layer, a slice layer, a macroblock layer, and a block layer. In the sequence layer, the method defines a quantization matrix. In a macroblock layer, the method defines a quantizer scale parameter in the macroblock layer, multiplies the quantization matrix times the quantizer scale parameter and stores the product in a quantization multiplication factor. In the block layer, the method parses an encoded data bitstream to detect a VLC code in the block layer and dequantizes the VLC code by multiplying the VLC code times the quantization multiplication factor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.