pfsclamp(1) [debian man page]

pfsclamp(1)						      General Commands Manual						       pfsclamp(1)

NAME

       pfsclamp - Clamp color and luminance channel values to be within the specified range

SYNOPSIS

       pfsclamp [--min <minimum>] [--max <maximum>] [--percentile] [--zero] [--rgb]

DESCRIPTION

       Use  this command to clamp values of luminance and color channels to be within the specified range. I.e. if a value in the channel is above
       the specified maximum or below specified minimum, set the value to either minimum or maximum.

       The command operates directly on XYZ channels.

OPTIONS

       --min <val>

	      Lower bound for clamping. Default value: 0.0001 (10^-4)

       --max <val>

	      Upper bound for clamping. Default value: 100000000 (10^8)

       --percentile, -p

	      Treat given min and max values as a percentile.

       --zero, -z

	      Set values out of clamping range to zero, instead of setting to specified maximum and minimum.

       --rgb

	      Perform clamping in RGB space.

EXAMPLES

       pfsin memorial.hdr | pfsclamp | pfsout memorial_cl.hdr

	      Remove possible out-of-range values, for examples zeros, from memorial image.

       pfsin memorial.hdr | pfsclamp --max 0.95 -p | pfsout memorial_cl.hdr

	      Remove 5% of the brightest pixels from the original image.

SEE ALSO

       pfsin(1) pfsout(1)

BUGS

       Please report bugs and comments to Rafal Mantiuk <mantiuk@mpi-sb.mpg.de> and Grzegorz Krawczyk <krawczyk@mpi-sb.mpg.de>.

																       pfsclamp(1)

pfsstat(1)						      General Commands Manual							pfsstat(1)

NAME

       pfsstat - Show frame / image statistics

SYNOPSIS

       pfsstat

DESCRIPTION

       This command will show a short text statistic on each image in the pfs stream. In the statistics you can find:

       File - name of the input file

       Width, Height - image dimensions

       Minimum - minimum luminance of an image(*), given in linear
	      units (relative luminance in cd/m^2) and logarithmic units

       Maximum - maximum luminance of an image(*)

       Average - average luminance of an image(*)

       Mean - mean luminance of an image(*)

       (*) Before min, max, average, median and dynamic range is computed, the following processing is performed on an image: 1) negative and zero
       values are replaced with the smallest positive value (to compute logarithms); 2) the image is low-pass  filtered.  The  low-pass  filtering
       removes	few very dark or very bright pixels that can significantly influence estimation of the dynamic range. The percentile, instead of a
       low-pass filter, is sometimes used for the same purpose. However, a low-pass filter is preferred to the percentile in pfstools since,  tak-
       ing into account the processing that is happening in the human visual system, low-frequency band filter is more plausible.

       Note: This command requires GNU Octave.

EXAMPLES

       pfsin memorial.hdr | pfsstat

       Show statistics for the memorial image.

BUGS

       Please report bugs and comments to Rafal Mantiuk <mantiuk@mpi-sb.mpg.de>.

																	pfsstat(1)