Patent ID: 7620263

Claim:
A signal processing method for enhancing a digital signal, comprising: enhancing pixels in the digital signal to generate an enhanced digital signal; and performing anti-clipping on the enhanced digital signal to generate an output signal, whereby one or more pixel values in the enhanced digital signal are adjusted to be within a selected lower and upper bounds, without introducing prominent unwanted artifacts in the output signal, wherein performing anti-clipping further includes: generating an alpha coefficient as a function of the current enhanced digital signal value, the corresponding digital signal value, a lower bound and an upper bound, wherein the alpha coefficient represents an amount of adjustment for the current enhanced digital signal value; filtering the alpha coefficient to generate a refined coefficient for the current enhanced digital signal value subtracting the digital signal from the enhanced digital signal to generate a first signal; multiplying the refined coefficient to the first signal to generate a second signal; and adding the second signal to the digital signal to generate said output signal; wherein the digital signal and the enhanced digital signal represent digital images.