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Pamsharpmap User Manual(0)                          Pamsharpmap User Manual(0)



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 loca-
       tion.

       Sharpness is a measure of how suddenly (in space) colors change in the image.  pamsharpmap computes the  sharp-
       ness  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  necessar-
       ily meaningful.

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


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.



netpbm documentation           07 February 2004     Pamsharpmap User Manual(0)