NAME

       pamsharpmap - create map of sharpness in a PNM/PAM image

SYNOPSIS

       pamsharpmap [imagefile]

DESCRIPTION

       This program is part of Netpbm(1).

       pamsharpmap  reads  a Netpbm image (PNM or PAM) and produces an image that shows how sharp
       it is at each location.

       Sharpness is a measure of how suddenly (in space) colors change in the image.  pamsharpmap
       computes  the  sharpness of each component color (R, G, B) separately and produces a pixel
       whose intensity of each component color is directly proportional to the sharpness of  that
       component color at the same location in the input image.  Thus, at a point where the image
       is very sharp in its red and green components, but dull in its blue  component,  you  will
       see a yellow pixel in the output.

       pamsharpmap  computes  sharpness  at a point simply as the average difference in intensity
       between the pixel at that point and the 8 pixels surrounding it.

       At the edges of the image, where there are not 8 pixels surrounding a  pixel,  pamsharpmap
       assumes the image is extended with a black border.

       pamsharpmap  assumes  that  the  image  is  a PNM or PNM equivalent PAM.  If it isn't, the
       results are not necessarily meaningful.

       The output image is the same dimensions, depth, and tuple  type  as  the  input,  and  has
       maxval 255.

OPTIONS

       There  are no command line options defined specifically for pamsharpmap, but it recognizes
       the options common to all programs based on libnetpbm (See
        Common Options ⟨index.html#commonoptions⟩ .)

SEE ALSO

       pamsharpness(1), pammasksharpen(1), pamedge(1), pam(1), pnm(1)

HISTORY

       pamsharpmap was added to Netpbm in Release 10.21 (March 2004).  Bryan Henderson derived it
       from  the  program  pnmsharp  by  B.W.  van  Schooten  and  distributed  as  part  of  the
       Photopnmtools package.

DOCUMENT SOURCE

       This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The  master
       documentation is at

              http://netpbm.sourceforge.net/doc/pamsharpmap.html