Image de-noising has become an essential exercise in medical imaging especially the Magnetic Resonance Imaging (MRI). The classical problem in the field of biomedical signal or image processing is the de-noising of image naturally corrupted by noise. Additive random noise can easily be removed using simple threshold methods. This paper proposes a medical image denoising algorithm using Discrete Wavelet Transform (DWT). Numerical results show that the algorithm can obtained higher peak signal to noise ratio (PSNR) through wavelet based denoising algorithm for MR images corrupted with random noise.

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Biomedical Image Processing De-noising DWT MRI Thresholding Random Noise. PSNR MAE (mean absolute error) and MSE(mean square error)