Adaptive noise reduction for digital display panels
AssigneeThomson Licensing
InventorsSebastien Weitbruch, Rainer Zwing, Carlos Correa
Life of this patent
Estimating the term…
Abstract
A plasma display panel is a pure linear display and does not provide a non-linear gamma behaviour like a CRT so that an artificial gamma function has to be applied to the signal in digital form. This gamma function increases the quantization steps in the dark areas whereas the quantization steps will be reduced in the luminous areas. The basic idea is to apply an adaptive noise filtering after the gammatization process. The adaptive filtering is a specific filtering which is adapted to the gammatization quantization noise. In other words, the filtering will be maximum for dark areas and its efficacy will be automatically decreased when the luminance of the area is increasing.
Claims13
1-12. (canceled)
Method for reducing noise caused by a quantization procedure during the signal processing of a display device with digitally driven pixels by digitally filtering a signal charged with said noise with a digital filter having a plurality of filter coefficients, said signal including a video level for each pixel of said display device,
- wherein
- varying at least one of said filter coefficients in dependence on the video level of the current pixel of said signal to be filtered.
Method according to claim 20, wherein, the function is the following:
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Device for reducing noise caused by a quantisation during the signal processing of a display device with digitally driven pixels including digital filter means for digitally filtering a video signal charged with said noise, said filter means having a plurality of filter coefficients, and said signal including a video level for each pixel of said display device,
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- controlling means connected to said digital filter means for varying at least one of said filter coefficients in dependence on the video level of the current pixel of said signal to be filtered.
Dependencies are inferred from the claim text.