"Digital Image Processing"--threshold threshold value of image segmentation--Shuangfeng method

In 1996, Prewitt proposed the histogram Shuangfeng method, that is, if the gray level histogram is obvious Shuangfeng, then the gray level of the valley between two peaks is chosen as the threshold value.

Note: The use of gray histogram Shuangfeng method to split the image, also requires a certain image prior knowledge, because the same histogram can correspond to a number of different images, the histogram only shows how many pixels in each gray level in the image, does not describe any of these pixel location information.

This method is not suitable for large and flat images of Shuangfeng differences or Shuangfeng between the histogram and the single-peak histogram.

In the early 70, the research work focused on the histogram transformation, but both histogram and histogram transform method only considered histogram gray information and neglected the spatial information of the image.