초록 ▼

The visibility of mosquito and blocking artifacts in a video compression system (200) are effectively suppressed by calculating a post-processed pixel intensity. A post-processed pixel intensity is determined (100) using a predetermined noise variance, a predetermined autocorrelation coefficient, an

The visibility of mosquito and blocking artifacts in a video compression system (200) are effectively suppressed by calculating a post-processed pixel intensity. A post-processed pixel intensity is determined (100) using a predetermined noise variance, a predetermined autocorrelation coefficient, and a local neighborhood of pixels that includes a plurality of previously post-processed pixel intensities and a plurality of original pixel intensities. This eliminates the dependency on local signal and noise power estimates.

대표청구항 ▼

[ I claim:] [1.] A method for obtaining a post-processed pixel intensity, for a frame in a decompressed video sequence residing in memory, using a filter which suppresses a visibility of a mosquito artifact and a blocking artifact based on a predetermined noise variance and a predetermined autocorre

[ I claim:] [1.] A method for obtaining a post-processed pixel intensity, for a frame in a decompressed video sequence residing in memory, using a filter which suppresses a visibility of a mosquito artifact and a blocking artifact based on a predetermined noise variance and a predetermined autocorrelation coefficient, comprising the steps of:A) creating a local neighborhood of pixels, in a memory unit, based on the decompressed video sequence, wherein the local neighborhood of pixels includes a plurality of previously post-processed pixel intensities and a plurality of decompressed pixel intensities;B) estimating a signal variance based on the local neighborhood of pixels;C) calculating an optimal filter gain based on the signal variance, the predetermined noise variance, and the predetermined autocorrelation coefficient; andD) determining, using a summer, the post-processed pixel intensity based on the predetermined autocorrelation coefficient, the local neighborhood of pixels, and the optimal filter gain,wherein the post-processed pixel intensity is further based on an estimate of an intensity of a selected pixel,wherein the estimate of the intensity of the selected pixel is a function of the predetermined autocorrelation coefficient, a decompressed pixel intensity of a next pixel relative to a predetermined scanning, and direction, and an immediately previously post-processed pixel intensity,wherein the estimate of the intensity of the selected pixel is determined by using an equation of the form: ]EQU5 ] where y.sub.a (n) is the estimate of the intensity of the selected pixel, .zeta. is the predetermined autocorrelation coefficient, x(n+1) is a decompressed pixel intensity of a next pixel relative to a predetermined scanning direction, and y.sub.b (n-1) is an immediately previously post-processed pixel intensity.