Source adaptive system and method for 2D iDCT
US7366236B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 2001 |
| Grant date | Apr 29, 2008 |
| Priority date | — |
| Expiry date | Sep 14, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention discloses a fast two-dimensional inverse Discrete Cosine Transform (iDCT) that adapts to compressed video source statistics to reduce execution time. iDCT algorithms for sparse blocks eliminate calculations for some zero coefficients and are implemented with quad-word parallel single-instruction-multiple-data (SIMD) multimedia instructions. It is observed that end-of-block marker value histograms vary little within single shots. An adaptive control mechanism is proposed that selects the optimal set of iDCTs to prepare for an entire shot from its first frames (to reduce software overheads and penalties). This introduces no degradation of decoded video quality as compared with a conventional SIMD 8×8 iDCT implemented with Intel MMX instructions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.