Fast DWT-based intermediate video codec optimized for massively parallel architecture
US9451291B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Aug 31, 2015 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Aug 31, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for scalable symmetric data compression and decompression (codec), optimized for real-time processing of high-resolution continuous-tone 2D input, such as video and images. Following a dyadic n-level DWT decomposition of input, the coding of subbands is spatially partitioned to enable strong parallelism that maps into concurrent encoding threads, based on typical artifacts of H-bands on initial levels—large areas of contiguous zeros interspersed with sparse and highly redundant non-zero values. Variable length codewords of both non-zero values and their positions are mapped into a linear bitstream by a combined limited sequential and parallel procedure of at most log2 n iterations, with both lossless and lossy variants enabled. The compressed bitstream of self-delimiting entries is decoded in a symmetric iterative procedure that delivers to decoding threads the non-zero values and position codewords for final image restoration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.