Modified nonlinear complex diffusion filter (MNCDF).
BACKGROUND
Speckle noise removal is the most important step in the processing of echocardiographic images. A speckle-free image produces useful information to diagnose heart-related diseases. Images which contain low noise and sharp edges are more easily analyzed by the clinicians. This noise removal stage is also a preprocessing stage in segmentation techniques.


METHODS
A new formulation has been proposed for a well-known nonlinear complex diffusion filter (NCDF). Its diffusion coefficient and the time step size are modified to give fast processing and better results. An investigation has been performed among nine patients suffering from mitral regurgitation. Images have been taken with 2D echo in apical and parasternal views.


RESULTS
The peak signal-to-noise ratio (PSNR), universal quality index (Qi), mean absolute error (MAE), mean square error (MSE), and root mean square error (RMSE) have been calculated, and the results show that the proposed method is much better than the previous filters for echocardiographic images.


CONCLUSIONS
The proposed method, modified nonlinear complex diffusion filter (MNCDF), smooths the homogeneous area and enhances the fine details.
Department of Electrical Engineering, Indian Institute of Technology Roorkee, A-28/1 Subhash Nagar, Roorkee, 247667, Uttarakhand, India. kal_2312@rediffmail.com.
Kalpana
K
Saini
Department of Electrical Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India.
M L
ML
Dewal
Department of Cardiology, Advanced Cardiac Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
Manojkumar
M
Rohit
Blurring; Diffusion coefficient; Echocardiographic images; Mitral regurgitation; Nonlinear complex diffusion; Speckle