otsu自适应阈值分割 用于图像分割二值化-otsu adaptive thresholding segmentation for image binarization

Niblack, (Efficient computation of adaptive threshold surfaces for image binarization)

The implemented Sauvola method uses integral images for fast computation of the threshold function. The Sauvola method is described in: J. Sauvola and M. Pietikainen, Adaptive document image binarization, Pattern Recognition 33, 2000. - ht