OpenCV で Non-local Means フィルタ

nonlocal-means.py

import cv2
import numpy as np

def nlmeans(i, o, h=10, hColor=10, templateWindowSize=9, searchWindowSize=27):
    img = cv2.imdecode(np.frombuffer(open(i, "rb").read(), np.uint8), cv2.IMREAD_COLOR | cv2.IMREAD_ANYDEPTH)
    denoised = cv2.fastNlMeansDenoisingColored(img, h=h, hColor=hColor, templateWindowSize=templateWindowSize, searchWindowSize=searchWindowSize)
    ok, bin = cv2.imencode(".png", denoised, [cv2.IMWRITE_PNG_COMPRESSION, 9])
    assert ok
    open(o, "wb").write(bin.tobytes())

nlmeans("input.png", "output.png", 10, 10, 9, 27)