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)