Efficient de-quantization in a digital video decoding process using a dynamic quantization matrix for parallel computations
US6507614B1 · kind B1 · utility
Assignees
Inventor
Key dates
| Filing date | Oct 19, 1999 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Oct 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An efficient digital video (DV) decoder process that utilizes a specially constructed quantization matrix allowing an inverse quantization subprocess to perform parallel computations, e.g., using SIMD processing, to efficiently produce a matrix of DCT coefficients. The present invention utilizes a first look-up table (for 8×8 DCT) which produces a 15-valued quantization scale based on class number information and a QNO number for an 8×8 data block (“data matrix”) from an input encoded digital bit stream to be decoded. The 8×8 data block is produced from a deframing and variable length decoding subprocess. An individual 8-valued segment of the 15-value output array is multiplied by an individual 8-valued segment, e.g., “a row,” of the 8×8 data matrix to produce an individual row of the 8×8 matrix of DCT coefficients (“DCT matrix”). The above eight multiplications can be performed in parallel using a SIMD architecture to simultaneously generate a row of eight DCT coefficients. In this way, eight passes through the 8×8 block are used to produce the entire 8×8 DCT matrix, in one embodiment consuming only 33 i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.