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pfsstat(1) [debian man page]

pfsstat(1)						      General Commands Manual							pfsstat(1)

pfsstat - Show frame / image statistics SYNOPSIS
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 <>. pfsstat(1)

Check Out this Related Man Page

pfsclamp(1)						      General Commands Manual						       pfsclamp(1)

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 <> and Grzegorz Krawczyk <>. pfsclamp(1)

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