This paper compares theKHandKJsign images in the context of the zero-thresholding at single and multiple scales. A function in the real number field is given for implementing the transformation from theKHcoordinate to the KJ coordinate. It is shown that the consistent zero-thresholding inequalityεK≥2H-εH+ε2Hmaintains effectiveness for both KH and KJ sign images. Therefore

from the viewpoint of zero-thresholding

theKHsign image is virtually a better choice for surface segmentation.