1Ppmtogif User Manual(0)                                Ppmtogif User Manual(0)
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NAME

6       ppmtogif - replaced by pamtogif
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8       This program is part of Netpbm(1).
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SYNOPSIS

12       ppmtogif was replaced in Netpbm 10.37 (December 2006) by pamtogif(1).
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14       pamtogif is mostly backward compatible with ppmtogif.
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DESCRIPTION

18       One  way  pamtogif  is not backward compatible with ppmtogif is that to
19       specify a transparency (alpha)  mask  with  ppmtogif,  you  supply  the
20       transparency  as a separate pseudo-PGM image and use the -alpha option,
21       whereas with pamtogif, you supply an input image that has the transpar‐
22       ency integrated into it, and there is no -alpha option.
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24       ppmtogif still exists as a separate program for backward compatibility,
25       but it runs pamtogif to do the essential work.  The compatibility  ppm‐
26       togif interprets an -alpha option by reading the transparency image and
27       combining it with the input image, then feeding pamtogif  the  combined
28       image  it  expects.   Other  than that, the compatibility ppmtogif just
29       passes input and options directly to pamtogif.
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31       You should not make any new use of ppmtogif and if you modify an exist‐
32       ing  use, you should upgrade to pamtogif.  But note that if you write a
33       program that might have to be used with old  Netpbm,  ppmtogif  is  the
34       only way to do that.
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36       Unless you use the -alpha option, you can simply change the name of the
37       program.  If you use -alpha, here is how to upgrade:
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39         $ ppmtogif -alpha=myalpha.pgm myinput.ppm >myoutput.gif
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41       becomes
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43         $ pamstack -tupletype=RGB_ALPHA myinput.ppm myalpha.pgm |  \
44             pamtogif >myoutput.gif
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Original Ppmtogif

49       If you are using Netpbm before 10.37, pamtogif doesn't  exist,  so  you
50       use  ppmtogif.   You can use the pamtogif manual for ppmtogif, with the
51       following exceptions.
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53       The current documentation of pamtogif documents all  versions  of  that
54       program.  Use the information for Version 10.37 only.
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56       ppmtogif before Netpbm 10.31 does not accept PAM input at all.
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58       ppmtogif does not accept PAM input with transparency information in it.
59       Instead, ppmtogif has an -alpha option.
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61       The syntax of the option is -alpha=pgmfile.  ppmtogif treats  the  con‐
62       tents of the named PGM file the same as pamtogif treats the alpha plane
63       of a PAM.  The PGM image must have the same  dimensions  as  the  input
64       file.   But unlike the PAM case, the alpha image need not have the same
65       maxval as the input.  ppmtogif interprets the alpha file using the  al‐
66       pha file's maxval.
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68       You cannot specify both -transparent and -alpha.
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DOCUMENT SOURCE

71       This  manual  page was generated by the Netpbm tool 'makeman' from HTML
72       source.  The master documentation is at
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74              http://netpbm.sourceforge.net/doc/ppmtogif.html
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76netpbm documentation                                   Ppmtogif User Manual(0)
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