Abstract

• In clinical surgery, the quality of endoscopic image is degraded by noise. Bloods, illumination changes, specular reflection and other factors contributes to noise affect doctor’s judgement, and cause high operation risk. In this research, degraded image is restored by using linear and non linear methods to make better enhancement. For noise removal, arithmetic mean, harmonic mean, contraharmonic mean and median filters are used. Unsharp masking filter is used to make sharping image. Gamma correction method is used for color enhancement and tone-mapping. The simulation programs are written using MATLAB. Both linear and non-linear filters are analyzed for specific image processing. The results of these two classes of filter are compared by Image Quality Assessment (IQA). This research assists the physicians to determine the diseases by applying linear and non-linear filter over the endoscopic image that have degraded factors.