Fig. 1
From: Lung nodule pre-diagnosis and insertion path planning for chest CT images
Lung parenchyma segmentation. Typical categories for pulmonary nodules: a juxta-pleural pulmonary nodule. b Juxta-vascular pulmonary nodule. c Solitary pulmonary nodule. An example of chest CT image, d original image, e gray histogram. The numbers represent as below: 1-outside visual field, 2-air, 3-lung parenchyma, 4-other lung tissues such as muscle, fat, trachea, vessels, etc., and 5-bone. f Workflow diagram of lung parenchyma segmentation. g Flow chart of preliminary segmentation with adaptive thresholding method