1IM_HISTPLOT(3)             Library Functions Manual             IM_HISTPLOT(3)
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NAME

6       im_histplot - graph an image of one horizontal or vertical line
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SYNOPSIS

9       #include <vips/vips.h>
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11       int im_histplot(in, out)
12       IMAGE *in, *out;
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DESCRIPTION

16       im_histplot(3)  plots  a  graph  of a horizontal or vertical image file
17       with one line. It is suitable for displaying the  output  of  histogram
18       functions such as im_histgr(3) and for displaying line profiles.
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20       Note  that  if  you try to directly plot the result of im_histgr(3) you
21       will often get a very, very large image, since im_histplot(3) will draw
22       an  image  as high (or as wide) as the largest pixel value in the image
23       (potentially huge). Use im_histnorm(3) to normalise the histogram maxi‐
24       mum before plotting.
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26       The  input  image should be either one horizontal line (Ysize=1) or one
27       vertical line (Xsize=1).  If the image is FMTUCHAR, the graph is  drawn
28       as  256  by  line-length  pixels. For all other unsigned integer types,
29       im_histplot(3) finds the image maximum, and draws the graph as  max  by
30       line-length pixels.
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32       For  signed  integer  types,  im_histplot(3) finds minimum and maximum,
33       moves min up to zero, and draws the graph as min +  max  by  line-lenth
34       pixels.
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36       For  float  types, im_histplot(3) finds minimum and maximum, and scales
37       the image range so as to make  the graph square.
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RETURNED VALUE

41       The function returns 0 on success and -1 on error.
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SEE ALSO

44       im_histgr(3), im_histnorm(3), im_extract(3).
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47       National Gallery and Birkbeck College, 1995
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51                                  10 May 1991                   IM_HISTPLOT(3)
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