公开(公告)号：US20180270479A1

公开(公告)日：2018-09-20

申请号：US15918646

申请日：2018-03-12

Applicant: MEDIATEK INC.

Inventor： Ching-Yeh CHEN ,  Tzu Der CHUANG ,  Chih-Wei HSU ,  Yu-Wen HUANG

IPC: H04N19/117 ,  H04N19/154 ,  H04N19/182 ,  H04N19/172 ,  H04N19/82 ,  H04N19/119 ,  H04N19/597

CPC classification number: H04N19/117 ,  H04N19/119 ,  H04N19/14 ,  H04N19/154 ,  H04N19/17 ,  H04N19/172 ,  H04N19/176 ,  H04N19/182 ,  H04N19/597 ,  H04N19/82

Abstract: Aspects of the disclosure provide a method for non-local adaptive loop filtering. The method can include receiving reconstructed picture, dividing the picture into current patches, forming patch groups each including a current patch and a number of reference patches, determining a noise level for each of the patch groups, and denoising the patch groups with a non-local denoising technology. The determining a noise level for each of the patch groups can include calculating a pixel variance for a respective patch group, determining a pixel standard deviation (SD) of the respective patch group according to the calculated pixel variance by searching in a lookup table that indicates mapping relationship between patch group pixel SDs and patch group pixel variances, and calculating a noise level for the respective patch group based on a compression noise model that is a function of the pixel SD.