US 12,266,082 B2
2D recursive de-banding
Jeroen Maria Kettenis, Geldern (DE)
Assigned to V-Silicon Semiconductor (Hefei) Co., Ltd, Hefei (CN)
Filed by V-Silicon Semiconductor (Hefei) Co., Ltd, Hefei (CN)
Filed on Jan. 28, 2022, as Appl. No. 17/587,936.
Prior Publication US 2023/0245286 A1, Aug. 3, 2023
Int. Cl. G06T 5/20 (2006.01); G06T 1/60 (2006.01); G06T 5/70 (2024.01); H04N 19/117 (2014.01)
CPC G06T 5/20 (2013.01) [G06T 1/60 (2013.01); G06T 5/70 (2024.01); G06T 2207/20012 (2013.01); G06T 2207/20032 (2013.01); H04N 19/117 (2014.11)] 15 Claims
OG exemplary drawing
 
1. A method of recursive filtering of image data, comprising:
receiving sequentially a plurality of original pixel values;
multiplying an original pixel value of a current pixel of the plurality of pixel values by a dynamically varying recursion coefficient;
generating a drift signal, low pass filtering the generated drift signal, and adding the filtered drift signal to recursively filtered pixel values for the current pixel;
adding the recursively filtered pixel values with drift signal from left and right neighbors of the current pixel, retrieved from a memory buffer holding filtered pixel data from a previous image line;
multiplying the added recursively filtered pixel values by 1 minus the dynamically varying recursion coefficient;
adding the two multiplication results together to yield a filtered pixel value for the current pixel;
writing the filtered pixel value for the current pixel back into the memory buffer;
detecting a detail comprising detail pixels and bypassing the recursive filtering of the detail pixels;
generating a residue signal from the bypassed detail pixels and adding the residue signal to the filtered pixel value; and
displaying the filtered pixel value with the residue signal on a display.