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)