Block-based noise estimation using adaptive Gaussian filtering

We propose a fast noise estimation algorithm using a Gaussian pre-filter. The coefficients of the Gaussian filter are selected according to the standard deviation of the Gaussian noise estimated from an input noisy image. The standard deviation is estimated from the difference image between the noisy input image and its filtered image. This algorithm can be applied to noise reduction in commercial image- or video-based applications such as digital cameras and digital television (DTV) for its performance and simplicity.