function EffectiveBW = get_matching_rnd_bandwidth(IDM)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% EffectiveBW = get_matching_rnd_bandwidth(IDM)         %
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%         %
% Extracts Image effective bandwidth by its Image       % 
% Degradation Measure (IDM)                             %
%                                                       %
% Inputs - IDM                                          %
% Output - the image's effective bandwidth estimation   %
%                                                       %
% Note: The file needs the Q_rnd_vec1000.mat file to run%
% properly                                              %
%                                                       %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Writen by -Barak Fishbain                             %
% Faculty of Engineering - Tel-Aviv University          %
% www.eng.tau.ac.il/~barak                              %
% November 2007                                         %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    load Q_rnd_vec1000.mat
    index = find (Q_rnd_vec(:,2) < IDM);
    if (length(index) == 0)
        EffectiveBW = 1;
    else
        Wm = IDM - Q_rnd_vec(index(1),2);
        Wp = Q_rnd_vec(index(1)-1, 2) - IDM;
        
        EffectiveBW = (Wp*Q_rnd_vec(index(1),1) + Wm*Q_rnd_vec(index(1)-1,1)) / (Wp + Wm);
    end