Automatic quantification of regional left ventricular deformation in volumetric ultrasound data remains challenging. Many methods have been proposed to extract myocardial motion, including techniques using block matching, phase-based correlation, dif

% [db,mag,pha,grd,w] = freqz_m(b,a); % db = Relative magnitude in dB computed over 0 to pi radians % mag = absolute magnitude computed over 0 to pi radians % pha = Phase response in radians over 0 to pi radians % grd = Group delay over 0 to pi