This function implements the Inertia Moment (IM) [1] method, only on a pixel-by time, 
  with the normalization of the co-occurrence matrix (COM) proposed by 
  CARDOSO, R.R. et al. [2]. The function returns the graphic IM method.
  Use as input data a 3D matrix created grouping NTIMES intensity matrices I(k)
  1<=k<=NTIMES

  I(k)=DATA(:,:,k)

  $GIM=\frac{1}{NTIMES-1}\sum\limits_{k=1}^{NTIMES-1}(I(k)-I(k+1))^2 \approx E[(I(k)-I(k+1))^2]$

  References:
  [1]  ARIZAGA, R. et al. Speckle time evolution characterization by the 
       co-occurrence matrix analysis. Optics and Laser Technology, Amsterdam, 
       v. 31, n. 2, p. 163-169, 1999.
  [2]  R.R. Cardoso, R.A. Braga, Enhancement of the robustness on dynamic speckle 
       laser numerical analysis, Optics and Lasers in Engineering, 
       Volume 63, December 2014, Pages 19-24, ISSN 0143-8166, 
       http://dx.doi.org/10.1016/j.optlaseng.2014.06.004.
 

  After starting the main routine just type the following command at the
  prompt:
  GIM = graphim(DATA);
    
  Input:
  DATA is the speckle data pack. Where DATA is a 3D matrix created grouping NTIMES 
       intensity matrices with NLIN lines and NCOL columns. When N=size(DATA), then
       N(1,1) represents NLIN and
       N(1,2) represents NCOL and
       N(1,3) represents NTIMES.
  SHOW [Optional] If SHOW is equal to string 'off', then do not plot the result.

  Output:
  GIM  returns the Generalized Difference matrix.


  For help, bug reports and feature suggestions, please visit:
  http://nongnu.org/bsltl

Package: bsltl