+The <guilabel>Audio Channels</guilabel> control sets the number of
+audio channels that the DCP will have. If the DCP has any channels
+for which there is no content audio they will be replaced by silence.
+You can only set an even number of channels here, since that is
+required by the DCI standard. If you want an odd number of channels,
+set the DCP channel count to one greater than you need and the
+unused channel will be filled with silence.
+</para>
+
+<para>
+The <guilabel>Processor</guilabel> control allows you to select a
+process to apply to the audio before it goes into the DCP. Three processes are currently provided:
+</para>
+
+<itemizedlist>
+<listitem>Mid-side decode — this will take a L/R
+stereo input and extract the common part (corresponding to the
+‘Mid’ in a mid-side signal) into the DCP's centre channel.
+The remaining L/R parts will be kept in the L/R channels of the DCP.
+This may be useful to make near-field L/R mixes more compatible with
+cinema audio systems.</listitem>
+<listitem>Stereo to 5.1 up-mixer A — this will take a stereo input and up-mix it to ‘fake’ 5.1. The input L/R are treated as follows:
+<itemizedlist>
+<listitem>DCP L is input L bandpass-filtered between 1.9kHz and 4.8kHz.</listitem>
+<listitem>DCP R is input R bandpass-filtered between 1.9kHz and 4.8kHz.</listitem>
+<listitem>DCP C is input L mixed with input R, taken down by 3dB and then bandpass-filtered between 150Hz and 1.9kHz.</listitem>
+<listitem>DCP Lfe is input L mixed with input R, taken down by 3dB and then bandpass-filtered between 20Hz and 150Hz.</listitem>
+<listitem>DCP Ls is input L bandpass-filtered between 4.8kHz and 20kHz.</listitem>
+<listitem>DCP Rs is input R bandpass-filtered between 4.8kHz and 20kHz.</listitem>
+</itemizedlist>
+<para>
+This upmixing algorithm is due to Gérald Maruccia.
+</para>
+</listitem>
+<listitem>Stereo to 5.1 up-mixer B — this uses a different approach:
+<itemizedlist>
+ <listitem>DCP L is input L.</listitem>
+ <listitem>DCP R is input R.</listitem>
+ <listitem>DCP C is input L + input R taken down by 3dB.</listitem>
+ <listitem>DCP Lfe is DCP C bandpass filtered between 20Hz and 150Hz.</listitem>
+ <listitem>DCP Ls and Rs are input L - input R with a 20ms delay.</listitem>
+</itemizedlist>
+</listitem>
+</itemizedlist>
+
+<!-- ============================================================== -->
+<section xml:id="sec-reels">
+<title>Reels</title>
+
+<para>
+A ‘reel’ in a DCP is a subsection of the DCP, in the same
+way as a 35mm reel is a section of a film. A DCP can be split up into
+any number of reels and the joins (the equivalent to 35mm splices)
+between the reels are seamless.
+</para>
+
+<para>
+There is no reason why you can't just use a single reel for the whole
+of your DCP, as there is no limit on their length. Many people choose
+to do this.
+</para>
+
+<para>
+There are, however, some possible advantages of splitting things up
+into reels:
+</para>
+
+<itemizedlist>
+<listitem>
+The picture, sound and subtitle data of the DCP will be
+split up into more smaller files on disk, rather than fewer larger
+files. This can be useful if the DCP is to be transferred on storage
+that have file size limits. The FAT32 filesystem, for example, can
+only hold files smaller than 4Gb. A 6Gb DCP with a single reel could
+not be transferred using a FAT32-formatted disk. If that DCP were
+split up into two 3Gb reels it could be transferred.
+</listitem>
+<listitem>
+It is easier to re-use DCP components if they are in reels. Consider,
+for example, a film company who wants to put a 5 second ident onto the
+beginning of DCPs that they distribute. If they receive a feature
+film DCP they can modify it to add their ident as a separate reel.
+This is easier than attaching the picture data in the DCP.
+</listitem>
+</itemizedlist>
+
+<para>
+DCP-o-matic offers three options for setting up the reels in your DCP:
+single reel, split by video content or custom.
+</para>
+
+<para>
+<guilabel>Single reel</guilabel>, as its name suggests, keeps the whole DCP as one reel.
+This is a perfectly good option if you have no particular reason to
+need reels.
+</para>
+
+<para>
+<guilabel>Split by video content</guilabel> puts each piece of source
+video content in its own reel, as shown in <xref linkend="fig-reels-by-video"/>.
+</para>
+
+<figure id="fig-reels-by-video">
+<title>Making reels using split by video content</title>
+<mediaobject><imageobject><imagedata scale="100" fileref="diagrams/reels-by-video&dia;"/></imageobject></mediaobject>
+</figure>
+
+<para>
+Here we have three video files (<code>ident.mp4</code>,
+<code>feature.ts</code> and <code>cred.mov</code>). With
+<guilabel>split by video content</guilabel> DCP-o-matic makes a new
+reel to hold each video file.
+</para>
+
+<para>
+<guilabel>Custom</guilabel> splits reels by the size of the files that
+will make up their video content. With <guilabel>Custom</guilabel>
+you must specify a reel length in Gb. Then no file in the DCP will be larger than this reel length.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section xml:id="sec-show-audio">
+<title>Show audio</title>
+
+<para>
+The <guilabel>Show Audio</guilabel> button will instruct DCP-o-matic
+to examine the audio in your content and plot a graph of its level
+over time. This can be useful for getting a rough idea of how loud
+the sound will be in the cinema auditorium. A typical plot is shown
+in <xref linkend="fig-audio-plot"/>
+</para>
+
+<figure id="fig-audio-plot">
+ <title>Audio plot</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/audio-plot&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The plot gives the audio level (vertical axis, in dB) with time
+(horizontal axis). 0dB represents full scale, so if there is anything
+near this you are in danger of clipping the projector's audio outputs.
+</para>
+
+<para>
+There are two plot types: the peak level and the RMS, which can be
+shown or hidden using the check-boxes on the right hand side of the
+window.
+</para>
+
+<para>
+The channel check-boxes will show or hide the plot(s) for
+the corresponding channels in the DCP.
+</para>
+
+<para>
+The smoothing slider applies a variable degree of temporal smoothing
+to the plots, which can make them easier to read in some cases.
+</para>
+
+<para>
+Obviously the audio plot is no substitute for listening in an
+auditorium, but it can be useful to get levels in the right rough area.
+</para>
+
+</section>
+
+</chapter>
+
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-templates" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+<title>Templates</title>
+
+<para>
+If you frequently make DCPs with similar settings you may find it
+useful to use templates.
+</para>
+
+<para>
+Say, for example, you often make 4K feature DCPs from video files in
+’scope at 25fps. You can speed up this process by following
+these steps:
+</para>
+
+<itemizedlist>
+ <listitem>Create a film with any content and set it up how you like;
+ in our example, set the content to scale to DCP, the DCP resolution
+ to 4K, and so on.</listitem>
+ <listitem>Choose <guilabel>Save as template...</guilabel> from the <guilabel>File</guilabel> menu.</listitem>
+ <listitem>Enter a name for your template.</listitem>
+</itemizedlist>
+
+<para>
+Then in the future you can create a new film, tick the
+<guilabel>Template</guilabel> box and choose your previously-saved
+template. The basic film's settings will come from your template, and
+when you add some content it will take on the settings of the
+first similarly-typed piece of content in your template.
+</para>
+
+<para>
+For example if the template has a piece of video content and some
+subtitles, any video that you add to the new film will take on the
+settings of the video in the template. Similarly, any subtitles that
+you add will take on the settings of the subtitles from the template.