pfstmo_fattal02(1)					      General Commands Manual						pfstmo_fattal02(1)

NAME

       pfstmo_fattal02 - Gradient domain high dynamic range compression

SYNOPSIS

       pfstmo_fattal02 [--alpha <val>] [--beta <val>] [--saturation <val>] [--noise <val>] [--verbose] [--help]

DESCRIPTION

       This command implements a tone mapping operator as described in:

       Gradient Domain High Dynamic Range Compression R. Fattal, D. Lischinski, and M. Werman In ACM Transactions on Graphics, 2002.

       With  respect to the original paper, this program provides additional parameter which limits the amplification of noise. The noise is often
       starkly amplified because of division by zero in one of the equations in the paper. Extension contributed by Przemyslaw Bazarnik.

       Results of this TMO can be improved by using a gamma correction.

OPTIONS

       --alpha <val>, -a <val>

	      Set alpha parameter. <val> defines the threshold gradient value (luminance differents of adjacent pixels) below which the  gradients
	      are amplified (detail enhancement) and above which the gradients are attenuated (global contrast reduction).
	       Suggested  range  is  1	to 0.0001. It is reasonable to change parameters by orders of magnitude, so for instance trying 0.1, 0.01,
	      0.001 etc.  (see paper for details).

       --beta <val>, -b <val>

	      Set beta parameter. <val> sets the strength of gradient (local contrast) modification.  Suggested range is 0.8 to  0.96  (see  paper
	      for details).  Value of 1 does not change contrasts, values above 1 reverse the effect: global contrast is stretched and details are
	      attenuated.  Values below 0.5 lead to very strong amplification of small contrast, so consider  using  --noise  parameter  close	to
	      'alpha' value to prevent noise.

       --saturation <val>, -s <val>

	      Amount of color saturation. Suggested range is 0.4 to 0.8. Default value: 0.6.

       --noise <val>, -n <val>

	      Reduces  gradient  amplification value for gradients close to 0 and reduces noise in the result. <val> defines gradient value (lumi-
	      nance differents of adjacent pixels) which is treated as noise. Suggested range is 0.0 to the value of alpha. Default  value  calcu-
	      lated based on alpha: 0.001*alpha.

       --verbose

	      Print additional information during program execution.

       --help

	      Print list of command line options.

EXAMPLES

       pfsin memorial.hdr | pfstmo_fattal02 -v | pfsgamma -g 2.2 | pfsout memorial.png

	      Tone map image and save it in png format.

SEE ALSO

       pfsin(1) pfsout(1) pfsview(1)

BUGS

       Please report bugs and comments on implementation to Grzegorz Krawczyk <krawczyk@mpi-sb.mpg.de>.

																pfstmo_fattal02(1)