function c = FastDCTAnalysis(x, fineness, par2, par3) % FastDctAnalysis -- Analysis operator for (overcomplete) dct dictionary % Usage % c = FastDCTAnalysis(x, fineness) % Inputs: % x the signal % fineness how many times finer the dictionary is compared to the % standard one, eg: 1, 2, 4, 8 ... % Output: % c the coefs % See Also: % FastDCTSynthesis, dct_iv % n = length(x); m = n*fineness; f = (1:(m-1))'; const = [n; .5 * (n + sin(2*pi*f/fineness) ./ (2*sin(pi*f/m)))]; const = const .^ .5; n2 = 2*n; m = n * fineness; y = zeros(4*m,1); y(2:2:n2) = x(:); z = fft(y); c = real(z(1:m)) ./ const;