initial commit

doc/user/eppm/index.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0"?>
+
+<!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
+	"file:///usr/share/xml/docbook/schema/dtd/4.4/docbookx.dtd">
+
+<chapter id="user-eppm"><title>Extended PPM (EPPM) Files</title>
+
+<p>EPPM is an extension to the PPM file format that allows specification of
+metadata.  The header of an EPPM file conforms to the following template:</p>
+
+<pre>P6#E
+# Tag1: Value
+# Tag2: Value
+# Tag3: Value
+# .
+# .
+# .
+Width Height Maxval
+Data
+</pre>
+
+<p>Tags recognized by ALE are outlined below.</p>
+
+<s><t>Black level</t>
+
+<p>The black level tag specifies a value that should be subtracted from
+all pixels in order to achieve linearity.  A modified version of dcraw (<a
+href="/darcs/dcraw">darcs repository</a>) can be used to generate files
+containing this tag.</p>
+
+<pre># Black-level: &lt;value&gt;
+</pre>
+
+</s><s><t>Exposure tags</t>
+
+<p>Exposure tags can be used for determining tonal registration through
+specification of shutter speed, aperture, and ISO sensitivity (or gain).</p>
+
+<pre># Shutter: &lt;value&gt;
+# Shutter: 1/&lt;value&gt;
+# Aperture: &lt;f-number&gt;
+# ISO: &lt;value&gt;
+# Gain: &lt;value&gt;
+</pre>
+
+</s>
+
+
+</chapter>