Research On Image Enhancement Technique For Enhancing Lung Nodules In Medical Chest X-Rays

Image enhancement is a basic image preprocessing tool, which have an important role in improving the quality of the original image and visual effects, Image enhancement methods for lung nodule in chest X-rays are researched in the paper, new image enhancement methods for enhancing lung nodules in chest X-rays is proposed in the paper. The content of the paper are summarized up as follows:Based on the characteristica of chest X-ray images and lung nodule images, the enhancement based on Laplace of Gaissian filter is firstly presented, The result show that the algorithm can efficiently enhance lung nodules in chest X-rays, but the method can not ehance lung nodule in chest X-rays by lung nodules in the physiongical characterstics in differrnt directions and the structures of lung nodules, so that ehanced ling nodules lose many detail imformation. Based on these drawbacks, the paper improves the conventional methods, A Laplacian of Gaussian Filter technique based on visual perception and directional scale for enhancing lung nodules in chest X-rays is proposed in this paper., The implementation of the proposed method is based on the modification of classical Laplacian of Gaussian (LoG) filter operation by assigning different scale values in different directions and consider visual factor to complete vision correction. Experiments show that the technique proposed in this paper can effectively enhance the lung nodules in the chest radiograph.Based on Mathematical Morphology method is proposed, which is employed to ehance lung nodules in chest X-rays, the result shows that the method can enhance lung nodules, but ehanced lung nodules and the backgrounds have poorly contrast., so a novel image enhancement method for enhancing lung nodules in chest X-rays based on morphological Top-Bottom-hat filter and Laplacian of Gaussian Filter with directional scale is proposed in this paper. First, the peak value image and the valley value image of a chest X-Ray image are computed by using morphological Top-hat and Bottom-hat filter, respectively. Then the image areas with spherical structure in the peak value image are then enhanced by using LoG filter with directional scale. In order to remove the effect of Gaussian smooth on visual effect of the chest X-Ray image, a visual correct factor is introduced into above mentioned operation. Finally, Top-hat and Bottom-hat are further combined and used for enhancing contrast of the whole chest X-Ray image. The experimental results illustrate the efficiency of the proposed algorithm.