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Methodology<br />

This has two stages, first is pre-processing of given MRI image and after that segmentation and<br />

then morphological operations.<br />

• Input image<br />

• Multiparameter Calculations<br />

• Segmentation o brain tumor using Region of Interest command<br />

Image Processing Techniques<br />

Median Filtering for Noise Removal<br />

Is a non-linear filtering technique used for noise removal. It is used to remove salt and pepper<br />

noise from the converted gray scale image. It replaces the intensity values of the center pixel with<br />

the median of the intensity values in the neighbourhood of that pixel. Median filters are particularly<br />

effective in the presence of impulse noise.<br />

Various De-noising Filters<br />

Mean Filter- Based on average value of pixels<br />

Median Filter – Based on the median value of pixels<br />

Wiener Filter – Based on inverse filtering in frequency<br />

Hybrid Filter – Combination of median and wiener filter<br />

Modified hybrid median filter – Combination of mean and median Filter<br />

Morphology Based De-noising- Based on Morphological opening and closing Operations.<br />

Image Enhancement<br />

Poor contrast is one of the defects found in acquired image. The effect of that defect has great<br />

impact on the contrast of image. When contrast is poor the contrast enhancement method plays an<br />

important role. The gray level of each pixel is scaled to improve the contrast. Contrast<br />

enhancements improve the visualization of the MRI image.<br />

Edge Detection<br />

Is an image processing technique for finding the boundaries of objects with in images. It works<br />

by detecting discontinuities in brightness. It is used for image segmentation and data extraction in<br />

areas such as image processing, computer vision, and machine vision.<br />

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