function r = dfftwav(wavfile)

%% settings
spectrumwidth = 96;
spectrumkeep = 24;
normcutoff = 5;

lumpwidth = 128;
lumpkeep = 32;


% get ready
[numsamples numchannels] = wavread(wavfile,'size');

samplespersecond = 44100;
chunkspersecond = 20;
samplesperchunk = samplespersecond / chunkspersecond;

numchunks = numsamples / samplesperchunk;

lumpsize = chunkspersecond * 30;
numlumps = numchunks / lumpsize;

pos = 1;

% walk thru wav
all = [];

for l = 1:numlumps
  lump = [];
  for i = 1:lumpsize
    last = pos + samplesperchunk - 1;
    if last > numsamples
      last = numsamples;
    end

%  [pos last]
    bit = wavread(wavfile,[pos,last]);

    % fft
    y = fft(bit,spectrumwidth*2);
    pyy = y.* conj(y) / spectrumwidth / 2;
    rpyy = pyy(1:spectrumkeep,:)';
    lump = [ lump ; rpyy ];

%    rpyy

    pos = pos + samplesperchunk;
  end

  % normalize lump
  [h w] = size(lump);
  for col = 1:normcutoff
    lump(:,col) = lump(:,col) / (normcutoff + 1 - col);
  end

  % fft lump
  y = fft(lump,lumpwidth*2);
  pyy = y.* conj(y) / lumpwidth / 2;
  rpyy = pyy(1:lumpkeep,:)';

  [w h] = size(rpyy);
  row = reshape(rpyy,[1 w*h]);

  all = [ all ; row ];

%  [l numlumps]

end

r = all';