[gimp-help-2] Add basic docs on the Sepia filter

[Alexandre Prokoudine <aprokoudine src gnome org>]

commit 4b1f6b7e6d8ed11b55e5721628259dd3e7159f38
Author: Alexandre Prokoudine <alexandre prokoudine gmail com>
Date:   Sun Jan 29 04:42:08 2017 +0300

    Add basic docs on the Sepia filter

 images/C/filters/examples/color-taj-sepia.jpg |  Bin 0 -> 32325 bytes
 images/C/menus/colors/desaturate/sepia.png    |  Bin 0 -> 32896 bytes
 src/menus/colors.xml                          |   19 +++---
 src/menus/colors/desaturate/sepia.xml         |   90 +++++++++++++++++++++++++
 src/menus/colors/filters.xml                  |    3 +
 5 files changed, 103 insertions(+), 9 deletions(-)
---
diff --git a/images/C/filters/examples/color-taj-sepia.jpg b/images/C/filters/examples/color-taj-sepia.jpg
new file mode 100644
index 0000000..e9d98eb
Binary files /dev/null and b/images/C/filters/examples/color-taj-sepia.jpg differ
diff --git a/images/C/menus/colors/desaturate/sepia.png b/images/C/menus/colors/desaturate/sepia.png
new file mode 100644
index 0000000..2ccd60b
Binary files /dev/null and b/images/C/menus/colors/desaturate/sepia.png differ
diff --git a/src/menus/colors.xml b/src/menus/colors.xml
index a3078f3..2c3b05e 100644
--- a/src/menus/colors.xml
+++ b/src/menus/colors.xml
@@ -41,16 +41,17 @@
   <xi:include href="colors/components/compose.xml"/>
   <xi:include href="colors/components/decompose.xml"/>
   <xi:include href="colors/components/recompose.xml"/>
+  <xi:include href="colors/desaturate/sepia.xml"/>
   <xi:include href="colors/map.xml"/>
-    <xi:include href="colors/map/rearrange-colormap.xml"/>
-    <xi:include href="colors/map/set-colormap.xml"/>
-    <!-- -->
-    <xi:include href="colors/map/alienmap2.xml"/>
-    <xi:include href="colors/map/exchange.xml"/>
-    <xi:include href="colors/map/gradientmap.xml"/>
-    <xi:include href="colors/map/palettemap.xml"/>
-    <xi:include href="colors/map/rotate-colormap.xml"/>
-    <xi:include href="colors/map/sample-colorize.xml"/>
+  <xi:include href="colors/map/rearrange-colormap.xml"/>
+  <xi:include href="colors/map/set-colormap.xml"/>
+  <!-- -->
+  <xi:include href="colors/map/alienmap2.xml"/>
+  <xi:include href="colors/map/exchange.xml"/>
+  <xi:include href="colors/map/gradientmap.xml"/>
+  <xi:include href="colors/map/palettemap.xml"/>
+  <xi:include href="colors/map/rotate-colormap.xml"/>
+  <xi:include href="colors/map/sample-colorize.xml"/>
   <xi:include href="colors/info.xml"/>
   <xi:include href="colors/info/histogram.xml"/>
   <xi:include href="colors/info/borderaverage.xml"/>
diff --git a/src/menus/colors/desaturate/sepia.xml b/src/menus/colors/desaturate/sepia.xml
new file mode 100644
index 0000000..736efd8
--- /dev/null
+++ b/src/menus/colors/desaturate/sepia.xml
@@ -0,0 +1,90 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE sect2 PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+                       "http://www.docbook.org/xml/4.3/docbookx.dtd";>
+
+<sect2 id="plug-in-sepia">
+  <title>Sepia</title>
+
+  <indexterm>
+    <primary>Colors</primary>
+    <secondary>Desaturate</secondary>
+    <tertiary>Sepia</tertiary>
+  </indexterm>
+  <indexterm>
+    <primary>Sepia</primary>
+  </indexterm>
+
+  <sect3>
+    <title>Overview</title>
+    <figure>
+      <title>Example for the <quote>Sepia</quote> filter</title>
+      <mediaobject>
+        <imageobject>
+          <imagedata format="JPG"
+            fileref="images/filters/examples/taj_orig.jpg"/>
+        </imageobject>
+        <caption>
+          <para>Original image</para>
+        </caption>
+      </mediaobject>
+      <mediaobject>
+        <imageobject>
+          <imagedata format="JPG"
+            fileref="images/filters/examples/color-taj-sepia.jpg"/>
+        </imageobject>
+        <caption>
+          <para><quote>Sepia</quote> filter applied</para>
+        </caption>
+      </mediaobject>
+    </figure>
+    <para>
+      The Sepia filter imitates sepia toning to produce a black-and-white 
+      picture with a warm brown-ish tone.
+    </para>
+  </sect3>
+
+  <sect3>
+    <title>Activate the filter</title>
+    <para>
+      You can find this command through
+      <menuchoice>
+        <guimenu>Colors</guimenu>
+        <guisubmenu>Desaturate</guisubmenu>
+        <guimenuitem>Sepia</guimenuitem>
+      </menuchoice>.
+    </para>
+  </sect3>
+
+  <sect3>
+    <title>Options</title>
+    <figure>
+      <title><quote>Sepia</quote> options</title>
+      <mediaobject>
+        <imageobject>
+          <imagedata fileref="images/menus/colors/desaturate/sepia.png" format="PNG"/>
+        </imageobject>
+      </mediaobject>
+    </figure>
+    <variablelist>
+      <varlistentry>
+        <term>Effect strength</term>
+        <listitem>
+          <para>
+            This handle lets you control how much the effect blends into 
+            the original image. 0.000 is no effect at all, 1.000 is 
+            completely replacing the image with its sepia-toned version.
+          </para>
+        </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term>sRGB</term>
+        <listitem>
+          <para>
+            This checkbox allows you processing the image in either sRGB 
+            gamma-corrected or linear color space.
+          </para>
+        </listitem>
+      </varlistentry>
+    </variablelist>
+  </sect3>
+</sect2>
diff --git a/src/menus/colors/filters.xml b/src/menus/colors/filters.xml
index e4bc7a5..36707ed 100644
--- a/src/menus/colors/filters.xml
+++ b/src/menus/colors/filters.xml
@@ -28,6 +28,9 @@
         <para><xref linkend="plug-in-hot"/></para>
       </listitem>
       <listitem>
+        <para><xref linkend="plug-in-sepia"/></para>
+      </listitem>
+      <listitem>
         <para><xref linkend="plug-in-max-rgb"/></para>
       </listitem>
       <listitem>