mirrfreq.m

binDCT fron D.Tran used in Image compression

function mmf=mirrfreq(LOT);
%  mmf=mirrfreq(LOT);
% Function to calculate the FB attenuation at mirror frequencies 

% Trac D. Tran 
% ECE Department, The Johns Hopkins University
% 3400 North Charles Street, 105 Barton Hall,
% Baltimore, MD 21218
% E-mail: [e-mail]
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
% Copyright (c) 2000 Trac D Tran
% This program is Copyright (c) by Trac D Tran.
% It may not be redistributed without the consent of the copyright
% holders. In no circumstances may the copyright notice be removed.
% The program may not be sold for profit nor may they be incorporated
% in commercial programs without the written permission of the copyright
% holders. This program is provided as is, without any express or
% implied warranty, without even the warranty of fitness for a
% particular purpose.
%-----------------------------------------------------------------------

[M,L]=size(LOT);N=L/M;
tmp=kron(0:2*pi/M:pi,ones(L/2,1)).*kron((L-1:-2:1)/2,ones(M/2+1,1))';
tmp=sort(abs(LOT(1,1:L/2)*cos(tmp)));
mmf=20*log10(max(tmp(1:M/2))/tmp(M/2+1));