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diff --git a/pamtopfm.html b/pamtopfm.html new file mode 100644 index 00000000..5068c574 --- /dev/null +++ b/pamtopfm.html @@ -0,0 +1,108 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<HTML><HEAD><TITLE>Pamtopfm User Manual</TITLE></HEAD> +<BODY> +<H1>pamtopfm</H1> +Updated: 10 April 2004 + +<A HREF="#index">Table Of Contents</A> + +<A NAME="name"> </A> +<H2>NAME</H2> +pamtopfm - Convert Netpbm image to PFM (Portable Float Map) + +<A NAME="synopsis"> </A> +<H2>SYNOPSIS</H2> +<B>pamtopfm</B> +[<b>-endian=</b>{<b>big</b>|<b>little</b>}] +[<b>-scale=</b><i>float</i>] +[<I>imagefile</I>] + +<P>All options can be abbreviated to their shortest unique prefix. +You may use two hyphens instead of one. You may separate an option +name and its value with white space instead of an equals sign. + +<A NAME="description"> </A> +<H2>DESCRIPTION</H2> + +<p>This program is part of <a href="index.html">Netpbm</a>. + +<p><b>pamtopfm</b> reads a Netpbm image (PNM or PAM) and converts it +to a PFM (Portable Float Map) image. + +<p>The PFM (Portable Float Map) image format is a lot like PPM, but uses +floating point numbers with no maxval to achieve a High Dynamic Range +(HDR) format. That means it doesn't have a concept of absolute color +and it can represent generic light intensity information rather than +just visual information like PPM does. For example, two pixels that +are so close in intensity that the human eye cannot tell them apart +are not visually distinct, so a visual image format such as PPM would +have no reason to use different sample values for them. But an HDR format +would. + +<p>There are details of the PFM format in the <a href="pfm.html">PFM +Format Description</a>. + +<p><a href="http://www.debevec.org/HDRShop">USC's HDRShop +program</a> and a program called Lefty use it. + +<b>pamtopfm</b> creates a color PFM image if its input is RGB (PPM) +and a non-color PFM otherwise. + +<p>Use <a href="pfmtopam.html"><b>pfmtopam</b></a> to convert a PFM +image to Netpbm format. + + +<A NAME="options"> </A> +<H2>OPTIONS</H2> + +<DL COMPACT> +<DT><B>-scale=</b><i>float</i> + +<DD> + <P>This specifies the scale factor of the PFM image. + Scale factor is a component of the PFM format. + Default is 1.0. + +<DT><B>-endian=</b>{<b>big</b>|<b>little</b>} + +<DD> + <P>This specifies the endianness of the PFM image. The samples + in the raster of a PFM image are 4 byte IEEE floating point + numbers. A parameter of the IEEE format, and therefore the PFM + format, is endianness, i.e. whether the specified bytes are + ordered from low addresses to high addresses or vice versa. + + <p><b>big</b> means big endian -- the natural ordering; + <b>little</b> means little-endian, the Intel-friendly ordering. + + <p>Default is whichever endianness the machine on which <b>pamtopfm</b> + runs uses internally, which results in the faster execution. + +</DL> + +<A NAME="seealso"> </A> +<H2>SEE ALSO</H2> + +<B><A HREF="index.html">Netpbm</A></B>, +<B><A HREF="pfmtopam.html">pfmtopam</A></B>, +<B><A HREF="pam.html">pam</A></B> + +<A NAME="history"></a> +<h2>HISTORY</h2> + +<p><b>pamtopfm</b> was added to Netpbm in Release 10.22 (April 2004). + + +<HR> +<A NAME="index"> </A> +<H2>Table Of Contents</H2> +<UL> +<LI><A HREF="#name">NAME</A> +<LI><A HREF="#synopsis">SYNOPSIS</A> +<LI><A HREF="#description">DESCRIPTION</A> +<LI><A HREF="#options">OPTIONS</A> +<LI><A HREF="#seealso">SEE ALSO</A> +<LI><A HREF="#history">HISTORY</A> +</UL> +</BODY> +</HTML> |