+</chapter>
+
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-dcp" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+<title>DCP settings</title>
+
+<para>
+This chapter describes the settings that apply to the whole DCP. The
+controls for these settings are in the <guilabel>DCP</guilabel> tab of
+the main window, as shown in <xref linkend="fig-dcp-tab"/>.
+</para>
+
+<figure id="fig-dcp-tab">
+ <title>DCP settings tab</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/dcp-tab&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The first thing here is the name. This is generally set to the title
+of the film that is being encoded. If <guilabel>Use ISDCF
+name</guilabel> is not ticked, the name that you specify will be used
+as-is for the name of the DCP. If <guilabel>Use ISDCF name</guilabel>
+is ticked, the name that you enter will be used as part of a
+ISDCF-compliant name.
+</para>
+
+<para>
+Underneath the name field is a preview of the name that the DCP will
+get. To use a ISDCF-compliant name, tick the <guilabel>Use ISDCF
+name</guilabel> check-box. The ISDCF name will be composed using details
+of your content's soundtrack, the current date and other things that
+can be specified in the ISDCF name details dialogue box, which you can
+open by clicking on the <guilabel>Details</guilabel> button.
+</para>
+
+<para>
+If you want to take the ISDCF-compliant name that DCP-o-matic
+generates and modify it, click <guilabel>Copy as name</guilabel> and
+the ISDCF name will be copied into the <guilabel>Name</guilabel> box.
+You can then edit it as you wish. The DCP name should not matter (in
+that it should not affect how the DCP ingests or plays) but
+projectionists will appreciate it if you use the standard naming
+scheme as it makes it easier to identify details of the content.
+</para>
+
+<para>
+The <guilabel>Content Type</guilabel> option can be
+‘feature’, ‘trailer’ or whatever; select the
+required type from the drop-down list. On some projection systems
+this will affect where your content appears in the projector's server
+user interface, so take care to select an appropriate type.
+</para>
+
+<para>
+The <guilabel>Signed</guilabel> check-box sets whether or not the DCP
+is signed. This is rarely important; if in doubt, tick it.
+</para>
+
+<para>
+The <guilabel>Encrypted</guilabel> check-box will set whether the DCP
+should be encrypted or not. If this is ticked, the DCP will require a
+KDM to play back. Encryption is discussed in <xref
+linkend="ch-encryption"/>.
+</para>
+
+<para>
+If you use encryption DCP-o-matic will generate a random encryption
+key for you. To specify your own key, click the
+<guilabel>Edit..</guilabel> button next to the key.
+</para>
+
+<para>
+The <guilabel>Reels</guilabel> and <guilabel>Reel length</guilabel>
+controls specify how the DCP will be split up into
+‘reels’. See <xref linkend="sec-reels"/>.
+</para>
+
+<para>
+The <guilabel>Standard</guilabel> option specifies which of the two
+DCP standards DCP-o-matic should use. If in doubt, use SMPTE (the
+more modern of the two).
+</para>
+
+<para>
+Ticking the <guilabel>Upload DCP to TMS after it is made</guilabel>
+will ask DCP-o-matic to copy the finished DCP to your configured TMS (see <xref linkend="sec-prefs-tms"/>).
+</para>
+
+<para>
+At the bottom of the DCP tab are a further two tabs, one each to
+contain the settings for the DCP's video and audio parts.
+</para>
+
+<para>
+The <guilabel>Container</guilabel> option sets the ratio of the image
+in the DCP. If this ratio is different to the ratio used for any
+content, DCP-o-matic will pad the content with black. In simple cases
+this should be set to the same ratio as that for the the primary piece
+of video content. Alternatively, you might want to pillarbox a small
+format into a Flat container: in this case, select the small format
+for the content's ratio and ‘Flat’ for the DCP.
+</para>
+
+<para>
+The <guilabel>Frame Rate</guilabel> control sets the frame rate of
+your DCP. This can be a little tricky to get right. Ideally, you
+want it to be the same as the video content that you are using. If it
+is not the same, DCP-o-matic must resort to some tricks to alter your
+content to fit the specified frame rate. Frame rates are discussed in
+more detail in <xref linkend="ch-frame-rates"/>.
+</para>
+
+<para>
+The <guilabel>Use best</guilabel> button sets the DCP video frame rate
+to what DCP-o-matic thinks is the best given the content that you have
+added.
+</para>
+
+<para>
+The <guilabel>3D</guilabel> button will set your DCP to 3D mode if it
+is checked. A 3D DCP will then be created, and any 2D content will be
+made 3D compatible by repeating the same frame for both left and right
+eyes. A 3D DCP can be played back on many 3D systems (e.g. Dolby 3D,
+Real-D etc.) but not on a 2D system.
+</para>
+
+<para>
+The <guilabel>Resolution</guilabel> tab allows you to choose the
+resolution for your DCP. Use 2K unless you have content that is of
+high enough resolution to be worth presenting in 4K.
+</para>
+
+<para>
+The <guilabel>JPEG2000 bandwidth</guilabel>; setting changes how big
+the final image files used within the DCP will be. Larger numbers
+will give better quality, but correspondingly larger DCPs. The
+bandwidth can be between 50 and 250 megabits per second (Mbit/s).
+Most commercial DCPs use bit rates between 75 and 125 Mbit/s.
+</para>
+
+<para>
+<guilabel>Re-encode JPEG2000 data from input</guilabel> governs
+whether or not JPEG2000-encoded data from a piece of content (usually
+a DCP) will be re-used in the output data as-is or whether it will be
+decoded and re-encoded by DCP-o-matic. If the option is enabled
+DCP-o-matic will decompress any JPEG2000 data it finds and re-encode
+it. This is useful if you want to reduce the bitrate of a DCP.
+Usually you will achieve better quality and quicker results by leaving
+this option switched off.
+</para>
+
+<para>
+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. One process is 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>
+</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 or changeovers)
+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 to 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 has a file size limit. 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 to the feature's existing data.
+</listitem>
+</itemizedlist>
+
+<para>
+DCP-o-matic offers three options for setting up the reels in your DCP:
+<guilabel>single reel</guilabel>, <guilabel>split by video content</guilabel> or <guilabel>custom</guilabel>.
+</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.
+</para>
+
+<para>
+The following settings from the <guilabel>DCP</guilabel> tab are saved
+in templates:
+</para>
+
+<itemizedlist>
+ <listitem>“Use ISDCF name” checkbox</listitem>
+ <listitem>Content type (FTR, TLR etc.)</listitem>
+ <listitem>Container</listitem>
+ <listitem>Resolution</listitem>
+ <listitem>JPEG200 bandwidth</listitem>
+ <listitem>Video frame rate</listitem>
+ <listitem>Signed and encrypted checkboxes</listitem>
+ <listitem>Audio channels</listitem>
+ <listitem>Standard (Interop / SMPTE)</listitem>
+ <listitem>Audio processor</listitem>
+ <listitem>Reel type and length</listitem>
+ <listitem>Upload after make DCP checkbox</listitem>
+</itemizedlist>
+
+<para>
+In addition to this, the settings (but not the filenames) of any
+content in the template are stored, as discussed above. The status of
+the <guilabel>Keep video and subtitles in sequence</guilabel> checkbox
+from the timeline is also preserved.
+</para>
+
+</chapter>
+
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-export" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+ <title>Export</title>
+
+ <para>
+ As well as creating DCPs from the content you specify, DCP-o-matic
+ can also export projects to ProRes and MP4 files. This is most
+ often useful to convert DCPs to a file that is smaller and easier to play back.
+ </para>
+
+ <para>
+ To convert a DCP to ProRes or MP4, the first step is start a new
+ project and import the DCP (see <xref
+ linkend="ch-manipulating-existing-dcps"/>). Then, choose
+ <guilabel>Export...</guilabel> from the <guilabel>Jobs</guilabel>
+ menu to open the export dialogue, as shown in <xref linkend="fig-export"/>.
+ </para>
+
+ <figure id="fig-export">
+ <title>Export dialogue</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/export&scs;"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <para>
+ From this dialogue you can select the required output format,
+ output file and, in the case of MP4, the quality of the output
+ file (by setting the <ulink url="https://trac.ffmpeg.org/wiki/Encode/H.264#crf">CRF value</ulink>).
+ </para>
+
+ <para>
+ The useful range of CRF values is from 17 (high quality but large file size) to 28 (smaller file size and still reasonable quality).
+ </para>
+
+ <para>
+ The time needed to export, and the resulting size, depend partly on the DCP resolution set in the project. To change that, see chapter <xref linkend="ch-dcp"/>.
+ </para>
+
+ <para>
+ You can also choose whether to mix down multichannel sources to stereo and whether you want to write separate reels to separate files.
+ </para>
+</chapter>
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-encryption" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+<title>Encryption</title>
+
+<para>
+DCP's do not have to be encrypted, but they can be. This
+chapter discusses the basic principles of DCP encryption, and how
+DCP-o-matic can create encrypted DCPs and KDMs for them.
+</para>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Basics</title>
+
+<para>
+DCPs can be encrypted. This means that the picture and sound data are
+encoded in such a way that only cinemas ‘approved’ by the
+DCP's creators can read them. In particular, this means copies of the
+DCP can be distributed by insecure means: if a bad person called
+Mallory obtains a hard drive containing an encrypted DCP, there is no
+way that he can play it. Only those cinemas who receive a correct key
+delivery message (KDM) can play the DCP.
+</para>
+
+
+<!-- ============================================================== -->
+<section>
+<title>How it works</title>
+
+<para>
+This section attempts to summarise how DCP encryption works. You can
+skip it if you like. You may need some knowledge of encryption
+methods to understand it.
+</para>
+
+<para>
+We suppose that we are trying to send a DCP to
+Alice's cinema without a third party called Mallory being able to
+watch it himself.
+</para>
+
+<para>
+There are two main families of encryption techniques. The first,
+symmetric-key encryption, allows us to encode some data using some
+numeric key. After encoding, no-one can decode the data unless they
+know the key.
+</para>
+
+<para>
+The first step in a DCP encryption is to encode its data with a random key
+using symmetric-key encryption. The encrypted DCP can then be sent
+anywhere, safe in the knowledge that even if Mallory got hold of a
+copy, he could not decrypt it.
+</para>
+
+<para>
+Alice, however, needs to know the key so she can play the DCP in her
+cinema. A simple approach might be for us to send Alice the key.
+However, if Mallory can intercept the DCP, he might also be able to
+intercept our communication of the key to Alice. Furthermore, if Alice
+happened to know Mallory, she could just send him a copy of the key.
+</para>
+
+<para>
+The clever bit in the process requires the use of public-key
+encryption. With this technique we can encrypt a block of data using
+some ‘public’ key. That data can then only be decrypted
+using a corresponding private key which is
+<emphasis>different</emphasis> to the public key. The private and
+public keys form a pair which are related mathematically, but it is
+extremely hard (or rather, virtually impossible) to derive the private
+key from the public key.
+</para>
+
+<para>
+Public-key encryption allows us to distribute the DCP's key to Alice
+securely. The manufacturer of Alice's projector generates a public
+and private key. They hide the private key inside the projector where
+no-one can read it. They then make the public key available to anyone
+who is interested.
+</para>
+
+<para>
+DCP-o-matic has a similar arrangement except that it stores its
+private keys in the user's configuration file. See <xref
+linkend="sec-decrypting"/> for details of how to share DCP-o-matic's
+certificate so that others can make encrypted DCPs for DCP-o-matic.
+</para>
+
+<para>
+We take our DCP's symmetric key and encrypt it using the public key of
+Alice's projector. We send the result to Alice over email (using a
+format called a Key Delivery Message, or KDM). Her projector then
+decrypts our message using its private key, giving the
+symmetric key which can decrypt the DCP.
+</para>
+
+<para>
+If is fine if Mallory intercepts our email to Alice, since the only
+key which can decrypt the message is the private key buried inside
+Alice's projector. The projector manufacturer is very careful that
+no-one ever finds out what this key is. Our DCP is secure: only Alice
+can play it back, since only her projector knows the key (even Alice
+does not).
+</para>
+
+</section>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Encryption using DCP-o-matic</title>
+
+<para>
+There are two steps to distributing an encrypted DCP. First, the
+DCP's data must be encrypted, and secondly KDMs must be generated for
+those cinemas that are allowed to play the DCP.
+</para>
+
+<para>
+The first part is simple: ticking the <guilabel>Encrypted</guilabel>
+box in the <guilabel>DCP</guilabel> tab will instruct DCP-o-matic to
+encrypt the DCP that it makes using a random key that DCP-o-matic
+generates. The key will be written to the film's metadata file, which
+should be kept secure.
+</para>
+
+<para>
+A DCP that is generated with the <guilabel>Encrypted</guilabel> box
+ticked will not play on any projector as-is (it will be marked as
+‘locked’, or whatever the projector manufacturer's term
+is).
+</para>
+
+<para>
+The second part of distributions is to generate KDMs for the cinemas
+that you wish to allow to play your DCP. There are two approaches to
+this within DCP-o-matic: using the project, or using a DKDM. These
+approaches are now described in turn.
+</para>
+
+<section>
+<title>Creating KDMs from a DCP-o-matic project</title>
+
+<para>
+You can create KDMs from inside a DCP-o-matic project using the
+<guilabel>Make KDMs</guilabel> option on the <guilabel>Jobs</guilabel>
+menu. This will open the KDM dialogue box, as shown in <xref
+linkend="fig-kdm"/>.
+</para>
+
+<figure id="fig-kdm">
+ <title>KDM dialog</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="35" fileref="screenshots/kdm&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+In order to generate KDMs for a particular projector, you need to know
+its <emphasis>certificate</emphasis>. These are usually made
+available by the projector manufacturers as text files with a
+<code>.pem</code> extension.
+</para>
+
+<para>
+DCP-o-matic can store these certificates along with details of their
+cinemas and screens within those cinemas. Each screen has a
+certificate for its projector (and optionally certificates for other
+trusted devices, such as the sound processor). DCP-o-matic can
+generate KDMs for any screens that it knows about.
+</para>
+
+<para>
+To add a cinema, click <guilabel>Add Cinema...</guilabel>. This opens
+a dialogue box into which you can enter the cinema's name, and
+optionally an email address. This email address can be used to
+get DCP-o-matic to deliver KDMs via email.
+</para>
+
+<para>
+Once you have added a cinema, select it by clicking on its name, then
+click <guilabel>Add Screen...</guilabel>. The resulting dialogue
+allows you to enter a name for the screen and load in its certificate
+from a file. The certificate should be in SHA256 PEM format.
+</para>
+
+<para>
+Alternatively, certificates for projection systems made by some
+manufacturers can be downloaded from databases provided by the
+manufacturer. Currently this is supported for Doremi, Dolby, Barco,
+Christie and GDC equipment (through downloading Barco, Christie or GDC
+certificates requires you to have an appropriate account set up in
+DCP-o-matic's preferences). If you are targeting a screen with
+equipment by one of these manufacturers you can click
+<guilabel>Download</guilabel> then enter the serial number of the
+server in the screen and click <guilabel>Download</guilabel> again
+and, all being well, the certificate will be fetched. Most cinema
+projection or technical departments will know these serial numbers.
+</para>
+
+<para>
+Note that the reliability of the manufacturers' certificate databases
+cannot be guaranteed. It is vital that KDMs are tested by the
+destination cinema will in advance of show time to identify any
+problems.
+</para>
+
+<para>
+Once you have set up all the screens that you need KDMs for, select
+the CPL that you want to create the KDM for. You can use the
+drop-down list to select the CPLs in the current film project, or load
+a CPL from somewhere else. Select the cinemas and/or screens that you
+want KDMs for and fill in the start and end dates and times.
+</para>
+
+<para>
+You must also select the type of KDM that you want to generate. If in
+doubt, use <guilabel>Modified Transitional 1</guilabel>.
+</para>
+
+<note>
+The differences between the three KDM types are fairly subtle.
+<guilabel>DCI Specific</guilabel> and <guilabel>DCI Any</guilabel> add
+a <code><ContentAuthenticator></code> tag to the KDM which
+allows the exhibitor to check that the DCP and KDM have come from a
+bona-fide source. In addition, <guilabel>DCI Specific</guilabel> adds
+information on trusted devices to the KDM. This allows the KDM
+creator to specify devices (such as sound processors) that are allowed
+to use keys delivered by the KDM. At present it is not clear how
+widely the <guilabel>DCI Specific</guilabel> and <guilabel>DCI
+Any</guilabel> features are supported (or even tolerated) by servers
+so you are advised to use <guilabel>Modified Transitional
+1</guilabel>.
+</note>
+
+<para>
+Finally, choose what you want to do with the KDMs. They can be
+written to disk, to a location that you can specify by clicking
+<guilabel>Browse</guilabel>. Alternatively, if you choose
+<guilabel>Send by email</guilabel> the KDMs will be zipped up and
+emailed to the appropriate cinema email addresses. Click
+<guilabel>Make KDMs</guilabel> to generate the KDMs.
+</para>
+
+</section>
+
+<section>
+<title>Creating KDMs using a DKDM</title>
+</section>