1Pamdepth User Manual(0)                                Pamdepth User Manual(0)
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NAME

6       pamdepth - change the maxval in a Netpbm image
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SYNOPSIS

10       pamdepth newmaxval [netpbmfile]
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DESCRIPTION

14       This program is part of Netpbm(1).
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16       pamdepth  reads  a  Netpbm image as input, scales all the pixel values,
17       and writes out the image with the new maxval.  Scaling the colors  down
18       to a smaller maxval will result in some loss of information.
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20       This program works on multi-image streams.
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22       Be  careful  of  off-by-one  errors  when choosing the new maxval.  For
23       instance, if you want the color values to be five bits wide, use a max‐
24       val of 31, not 32.
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26       One  important  use  of pamdepth is to convert a new format 2-byte-per-
27       sample PNM file to the older 1-byte-per-sample  format.   Before  April
28       2000,  essentially  all raw (binary) format PNM files had a maxval less
29       than 256 and one byte per sample, and many programs may rely  on  that.
30       If  you specify a newmaxval less than 256, the resulting file should be
31       readable by any program that worked with PNM files before April 2000.
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SEE ALSO

35       pnm(1), pam(1), pnmquant(1), ppmdither(1) ppmbrighten(1) pamfunc(1)
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HISTORY

39       pamdepth  was  new  in  Netpbm  10.32  (February  2006).   It  replaced
40       pnmdepth,  by  Jef  Poskanzer.   pamdepth  is  backward compatible with
41       pnmdepth and adds the ability to process arbitrary PAM images  and  the
42       ability  to  process  multi-image input streams.  pnmdepth handled only
43       PNM images and ignored all but the the first in any stream.
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47netpbm documentation             08 April 2000         Pamdepth User Manual(0)
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