diff options
| author | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2014-11-26 03:12:52 +0000 |
|---|---|---|
| committer | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2014-11-26 03:12:52 +0000 |
| commit | 2c37964394a4433c5324ff032c406e0e935b95ac (patch) | |
| tree | 0fde51b0ad938b663be1276fa2a3e597300c8f84 /ppmtoarbtxt.html | |
| parent | 34e2be30fbaa648d3ca1c76249d3d3f00287bb11 (diff) | |
| download | netpbm-mirror-2c37964394a4433c5324ff032c406e0e935b95ac.tar.gz netpbm-mirror-2c37964394a4433c5324ff032c406e0e935b95ac.tar.xz netpbm-mirror-2c37964394a4433c5324ff032c406e0e935b95ac.zip | |
miscellaneous update
git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@2326 9d0c8265-081b-0410-96cb-a4ca84ce46f8
Diffstat (limited to 'ppmtoarbtxt.html')
| -rw-r--r-- | ppmtoarbtxt.html | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/ppmtoarbtxt.html b/ppmtoarbtxt.html index 2fafbb8c..d6e97ddb 100644 --- a/ppmtoarbtxt.html +++ b/ppmtoarbtxt.html @@ -3,7 +3,7 @@ <BODY> <H1>ppmtoarbtxt</H1> <BR> -Updated: 27 April 2003 +Updated: 26 November 2014 <BR> <A HREF="#index">Table Of Contents</A> @@ -36,9 +36,16 @@ pixel, to stdout. The substitutions are as follows: <DT><B>#(ired</B><I> format blackref whiteref</I><B>)</B> <DD>generates an integer in the range <I>blackref</I> to -<I>whiteref</I> using <I>format</I> representing the red intensity of -the pixel. A red intensity of 0 becomes <I>blackref</I>; a red -intensity of maxval becomes <I>whiteref</I>. +<I>whiteref</I> in a format specified by <I>format</I> representing the red +intensity of the pixel. A red intensity of 0 becomes <I>blackref</I>; a red +intensity of maxval becomes <I>whiteref</I>, with the rest linearly +interpolated in between. + +<p><i>format</i> is a printf-like format specifier like "%d". +<b>ppmtoarbtxt</b> uses as the entire format string to a <b>fprintf</b> POSIX +library call whose only other argument is the red itensity as an integer data +type. <b>ppmtoarbtxt</b> does not verify that your format string makes sense; +there are values you could specify that could even crash the program. <p><B>#(ired)</B> is equivalent to <B>#(ired %d 0 255)</B>. @@ -60,8 +67,10 @@ intensity of maxval becomes <I>whiteref</I>. <DD>Same as <B>#(ired...</B>, but generates a floating point number instead of an integer. -<p> -<B>#(fred)</B> is equivalent to <B>#(fred %f 0.0 1.0)</B>. +<p>In this case, the second argument to the <b>fprintf</b> that uses +<i>format</i> has a double precision floating point data type. + +<p><B>#(fred)</B> is equivalent to <B>#(fred %f 0.0 1.0)</B>. <DT><B>#(fgreen</B><I> format blackref whiteref</I><B>)</B> |