sceneGet

Get scene parameters and derived properties 

     val = sceneGet(scene,parm,varargin)

 Scene properties are either stored as parameters or computed from those
 parameters. We generally store only unique values and to calculate all
 the derived values. 

  A '*' indicates that the syntax sceneGet(scene,param,unit) can be used, where
  unit specifies the spatial scale of the returned value:  'm', 'cm', 'mm',
  'um', 'nm'.  Default is always meters ('m').
 
 Examples
    scene = vcGetObject('scene');
    sceneGet(scene,'name')
    sceneGet(scene,'size);
    sceneGet(scene,'width','um')

 General parameters
      {'name'}     - name
      {'type'}     - always 'scene'
      {'filename'} - if derived from file, stored here
      {'rows'}     - number of row samples
      {'cols'}     - number of column samples
      {'size'}*    - scene size (rows,cols)
      {'height'}*  - height (meters), 
      {'width'}*   - width (meters) 
      {'heightandwidth'}*    - (height,width)
      {'diagonalsize'}*      - diagonal
      {'area'}*              - area (meters^2) 

 Optical and resolution properties
      {'objectdistance'}  - distance from lens to object
      {'wangular'}        - width angular field of view
      {'hangular'}        - height angular field of view
      {'diagonalfieldofview'} - diagonal field of view sqrt(h^2 + w^2)
      {'aspectratio'}     - row/col
      {'magnification','mag'}  -  Always 1.

 Radiance information
      {'data'}
        {'photons'}     - radiance data (photons) 
        {'datamax'}     - max radiance value
        {'datamin'}     - min radiance value
        {'compressbitdepth'}  - 16 bits, usually, of compression
        {'energy'}         - radiance data (energy)
        {'meanluminance'}  - mean luminance
        {'luminance'}      - spatial array of luminance

 Resolution parameters

      {'hspatialresolution'}*  - height spatial resolution (distance between pixels)
      {'wspatialresolution'}*  - width spatial resolution 
      {'spatialresolution'}*   - (height,width) spatial resolution
      {'samplespacing'}*       - (width,height) spatial resolution (do not use)
      {'distanceperdegree'}*   - sample spacing per deg of visual angle
      {'degreesperdistance'}   - degrees per unit distance, e.g.,  sceneGet(scene,'degPerDist','micron')
      {'spatialsupport'}       - spatial locations of points e.g., sceneGet(oi,'spatialsupport','microns')
      {'hangularresolution'}   - height degrees per pixel
      {'wangularresolution'}   - width degrees per pixel
      {'angularresolution'}    - (height, width) degrees per pixel
      {'frequencyresolution'}* - 
         % Default is cycles per degree
         % val = sceneGet(scene,'frequencyResolution',units);
      {'maxfrequencyresolution'}*
         % Default is cycles/deg.  By using
         % sceneGet(oi,'maxfreqres',units) you can get cycles/{meters,mm,microns}
         % 
      {'frequencysupport'}*
         % val = sceneGet(scene,'frequencyResolution',units);
      {'fsupportx'}*
         % val = sceneGet(scene,'frequencyResolution',units);
      {'fsupporty'}*
         % val = sceneGet(scene,'frequencyResolution',units);

  Wavelength parameters
      {'spectrum'}
        {'binwidth'}   - bin width of wavelength integration
        {'wavelength'} - column vector of wavelength sample
        {'nwave'}      - number of wavelength samples

 Auxiliary information
      {'illuminant'}         - HDRS multispectral data illuminant stored here (watts/sr/m^2/nm) 
        {'illuminantdata'}   - energy data
        {'illuminantwave'}   - wavelength samples
        {'illuminantcomment'}- comment

 Copyright ImagEval Consultants, LLC, 2003.