function [delta1, delta2] = db2delta(Rp, As)

% -------------------------------------------------

% Converts dB specs Rp and As into

%   absolute specs delta1 and delta2

%  [delta1, delta2] = delta2db(Rp, As)

%  delta1 = passband tolerance ( or ripple), absolute specs

%  delta2 = stopband tolerance ( or ripple), absolute specs

%      Rp = passband ripple in dB

%      As = stopband attenuation in dB

%

temp = 10^(-Rp/20);

delta1 = (1-temp) / (1+temp);

delta2 = (1+delta1)*(10^(-As/20));

function [Rp, As] = delta2db(delta1, delta2)

% -------------------------------------------------

% Converts absolute specs delta1 and delta2 into

%   dB specs Rp and As

%  [Rp, As] = delta2db(delta1, delta2)

%  delta1 = passband tolerance ( or ripple), absolute specs

%  delta2 = stopband tolerance ( or ripple), absolute specs

%      Rp = passband ripple in dB

%      As = stopband attenuation in dB

%

Rp = -20 * log10( (1-delta1)/(1+delta1));

As = -20 * log10( delta2 / (1+delta1));