maskEllipse

PURPOSE ^

Creates a binary image of an ellipse.

SYNOPSIS ^

function mask = maskEllipse( mrows, ncols, varargin )

DESCRIPTION ^

 Creates a binary image of an ellipse.

 Creats a binary image of size (mrows x ncols), with all pixels off except
 inside of the specified ellipse.  The ellipse is given by 5 parameters, a
 semimajor axis of ra, a semminor axis of radius rb, angle phi (in
 radians), centered at (crow,ccol).An alternative method of specifying the
 ellipse parameters is in terms of the parameters of a 2d gaussian.  For
 more information on how a gaussian relates to an ellipse see
 gauss2ellipse.
 
 USAGE
  mask = maskEllipse( mrows, ncols, crow, ccol, ra, rb, phi )
  mask = maskEllipse( mrows, ncols, mu, C, [rad] )

 INPUTS [version 1]
  mrows   - number of rows in mask
  ncols   - number of columns in mask
  crow    - the row location of the center of the ellipse
  ccol    - the column location of the center of the ellipse
  ra      - semi-major axis length (in pixels) of the ellipse
  rb      - semi-minor axis length (in pixels) of the ellipse
  phi     - rotation angle (in radians) of semimajor axis to x-axis

 INPUTS [version 2]
  mrows   - number of rows in mask
  ncols   - number of columns in mask
  mu      - 1x2 vector representing the center of the ellipse
  C       - 2x2 cov matrix
  rad     - [2] Number of std to create the ellipse to

 OUTPUTS
  mask    - created image mask

 EXAMPLE
  mask = maskEllipse(  200, 200, 40, 100,  20, 15, pi/4 );
  figure(1); im(mask); [mu,C] = imMlGauss( mask, 0, 2 );

 See also PLOTELLIPSE, GAUSS2ELLIPSE, MASKCIRCLE, MASKGAUSSIANS, IMMLGAUSS

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:
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