NAME

       falsecolor - make a false color RADIANCE picture

SYNOPSIS

       falsecolor  [  -i input ][ -p picture ][ -cb | -cl | -cp ][ -e ][ -s scale ][ -l label ][ -n ndivs ][ -lw
       lwidth ][ -lh lheight ][ -log decades ][ -m mult ][ -pal palette ][ -r redv ][ -g grnv ][ -b bluv ]

       falsecolor -palettes

DESCRIPTION

       Falsecolor produces a false color picture for lighting analysis.  Input is a rendered Radiance picture.

       By default, luminance is displayed on a linear scale from 0 to 1000 cd/m2, where dark  areas  are  purple
       and  brighter  areas move through blue, green, red to yellow.  A different scale can be given with the -s
       option.  If the argument given to -s begins with an "a" for "auto," then the maximum is used for  scaling
       the  result.   The  default multiplier is 179, which converts from radiance or irradiance to luminance or
       illuminance, respectively.  A different multiplier can be given  with  -m  to  get  daylight  factors  or
       whatever.   For a logarithmic rather than a linear mapping, the -log option can be used, where decades is
       the number of decades below the maximum scale desired.

       A legend is produced for the new image with a label given  by  the  -l  option.   The  default  label  is
       "cd/m2",  which  is  appropriate  for standard Radiance images.  If the -i option of rpict(1) was used to
       produce the image, then the appropriate label would be "Lux".

       If contour lines are desired rather than just false color, the -cl option can be used.  These  lines  can
       be  placed  over  another  Radiance  picture using the -p option.  If the input picture is given with -ip
       instead of -i, then it will be used both as the source of values and  as  the  picture  to  overlay  with
       contours.   The  -cb  option produces contour bands instead of lines, where the thickness of the bands is
       related to the rate of change in the image.  The -cp option creates a posterization effect where  colours
       are  banded without the background image showing through.  The -n option can be used to change the number
       of contours (and corresponding legend entries) from the default value of 8.  The -lw and -lh options  may
       be used to change the legend dimensions from the default width and height of 100x200.  A value of zero in
       either eliminates the legend in the output.

       The  -e  option  causes  extrema  points  to  be printed on the brightest and darkest pixels of the input
       picture.

       The -pal option provides different color palettes for falsecolor.  The current choices are spec  for  the
       old  spectral  mapping, hot for a thermal scale, and pm3d for a variation of the default mapping, def.  A
       Radiance HDR image of all available palettes can be created with the  -palettes  option.   The  remaining
       options,  -r,  -g, and -b are for changing the mapping of values to colors.  These are expressions of the
       variable v, where v varies from 0 to 1.  These options are not recommended for the casual user.

       If no -i or -ip option is used, input is taken from the standard  input.   The  output  image  is  always
       written to standard output, which should be redirected.

EXAMPLES

       To create a false color image directly from rpict(1):

         rpict -vf default.vp scene.oct | falsecolor > scene.hdr

       To create a logarithmic contour plot of illuminance values on a Radiance image:

         rpict -i -vf default.vp scene.oct > irrad.hdr
         rpict -vf default.vp scene.oct > rad.hdr
         falsecolor -i irrad.hdr -p rad.hdr -cl -log 2 -l Lux > lux.hdr

AUTHOR

       Greg Ward
       Axel Jacobs (Perl translation and -pal options)

ACKNOWLEDGEMENT

       Work on this program was initiated and sponsored by the LESO group at EPFL in Switzerland.

SEE ALSO

       getinfo(1),  pcomb(1),  pcompos(1),  pextrem(1),  pfilt(1),  pflip(1),  protate(1),  psign(1),  rpict(1),
       ximage(1)

RADIANCE                                            12/12/11                                       FALSECOLOR(1)