The invention discloses a 
pulmonary nodule edge rebuilding and partitioning method based on a 
computed tomography (CT) image. According to the 
pulmonary nodule edge rebuilding and partitioning method, the image is subjected to 
spatial transformation by using a transformation method which has a sparse representation ability on gradient characteristics; a 
high energy transformation coefficient is reserved through shrinkage of a transformation domain; the image is rebuilt through inverse transformation to realize strengthening of the gradient characteristics; and amplification of small signals of the gradient characteristics is realized through multistage strengthening of the signals, a 
pulmonary nodule edge is rebuilt, and important edge information is provided for subsequent partitioning. The pulmonary nodule edge rebuilding and partitioning method provides a clustering-based pulmonary nodule partitioning 
algorithm, does not have the process of a training classifier, has a self-training ability, and can be used for strengthening 
edge detection, overcoming partitioning difficulty caused by uneven gray levels, and eliminating influence by 
speckle noise. The pulmonary nodule edge rebuilding and partitioning method can also be used for establishing a CT image partitioning 
algorithm evaluation system and combining contours drawn manually by different clinical medical experts into optimum partitioning standards so that the partitioning 
algorithm can be compared systematically, and the effectiveness of the partitioning algorithm can be revealed.