Image processing and display apparatus and method for tone resolution expansion of digital images
US7643180B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2006 |
| Grant date | Jan 5, 2010 |
| Priority date | — |
| Expiry date | Dec 9, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/407
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A tone step detector detects whether the tone of n-bit input image data varies gradually, and generates a tone processing control signal indicating that a tone step is contained. A bit shifter bit-shifts the n-bit input image data to the left by α bits, to generate (n+α)-bit image data. A tone processor smoothes the image data of the (n+α)-bit image data generated by the bit shifter, in the region where the tone processing control signal indicates that a tone step is contained, to generate (n+α)-bit image data having been smoothed in the above-mentioned region. Because of the selective smoothing, degradation in the image quality due to quantization is reduced even when an analog image signal whose tone varies gradually is input.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.