function dout = phase_correction(din,c);%PHASE_CORRECTION: Apply a constant Phase correction to seismic%                  data. The opimal correction can be determined%                  via the examination of the Kurtosis.%              %  see:  Longbottom, J., Walden, A.T. and White, R.E. (1988) Principles and %        application of maximum kurtosis phase estimation. Geophysical %        Prospecting, 36, 115-138.%%  [dout] = phase_correction(din,c);%%  IN   din:      Seismic data (traces in columns);%       c:        Constant Phase rotation in degrees%%  OUT  dout:     data after correction%%  Example: Make a 90.deg rotated wavelet and correct%           it back to 0.deg.  %%%      dt = 4./1000; fl=4, fh=30, c=90;%      [w,t] = make_a_rotated_wavelet(dt,fl,fh,c);%      [wout] = phase_correction(w,-c);%      plot_area(t,[w,wout],2,-40);%%%  Author(s): M.D.Sacchi (sacchi@phys.ualberta.ca)%  Copyright 1988-2005 SeismicLab%  Revision: 1.2  Date: Ago/2005%%  Signal Analysis and Imaging Group (SAIG)%  Department of Physics, UofA  c = c*pi/180;  [nt,nx]=size(din);  nf = 2^nextpow2(nt);  [nt,nx]=size(din);  Din = fft(din,nf,1);  Phase = exp(-i*[0;-c*ones(nf/2-1,1);0;c*ones(nf/2-1,1)]);   for k=1:nx;     Din(:,k) = Din(:,k).*Phase;   end dout = ifft(Din,nf,1); dout = real(dout(1:nt,:));