Quantization control for variable bit depth
US8548047B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2012 |
| Grant date | Oct 1, 2013 |
| Priority date | — |
| Expiry date | Aug 2, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The quantization parameter QP is well-known in digital video compression as an indication of picture quality. Digital symbols representing a moving image are quantized with a quantizing step that is a function QSN of the quantization parameter QP, which function QSN has been normalized to the most significant bit of the bit depth of the digital symbols. As a result, the effect of a given QP is essentially independent of bit depth a particular QP value has a standard effect on image quality, regardless of bit depth. The invention is useful, for example, in encoding and decoding at different bit depths, to generate compatible, bitstreams having different bit depths, and to allow different bit depths for different components of a video signal by compressing each with the same fidelity (i.e., the same QP).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.