+The easiest way to select the required conversion is to choose one of
+DCP-o-matic's presets. DCP-o-matic knows how to convert from four
+common colourspaces: sRGB, Rec. 601, Rec. 709 and P3. If you do not
+know which preset you should use, refer to the suggestions in <xref
+linkend="tab-colour-conversion"/>.
+</para>
+
+<table id="tab-colour-conversion">
+<title>Suggested colour conversion settings</title>
+<tgroup cols='2' align='left' colsep='1' rowsep='1'>
+<colspec colwidth='1*'/>
+<colspec colwidth='5*'/>
+<tbody>
+<row>
+<entry>sRGB</entry><entry>Still images in RGB, e.g. photographs.</entry>
+</row>
+<row>
+<entry>Rec. 601</entry><entry>Standard-definition content (fewer than about 1000 pixels across) including DVD rips.</entry>
+</row>
+<row>
+<entry>Rec. 709</entry><entry>High-definition content including Blu-Ray rips.</entry>
+</row>
+<row>
+<entry>P3</entry><entry>Content explicitly graded to P3.</entry>
+</row>
+</tbody>
+</tgroup>
+</table>
+
+<para>
+For other required colour conversions, and if you know what you are
+doing, you can choose <guilabel>Custom</guilabel> which will open the full
+colour conversion editing dialogue box:
+</para>
+
+<figure id="fig-colour-conversion">
+ <title>Dialogue box for custom colour conversion</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/colour-conversion&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+Alternatively, choose <guilabel>None</guilabel> if your source files
+are already in the XYZ colour space and require no conversion.
+</para>
+
+<para>
+DCP-o-matic's colour conversion processes are discussed in much more
+detail in a separate document <ulink
+url="https://dcpomatic.com/manual/colour.pdf">colour.pdf</ulink>.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Other settings</title>
+
+<para>
+The <guilabel>crop</guilabel> settings can be used to crop your
+content, which is often used to remove black borders from the edges of
+the image. The specified number of pixels will be trimmed from each
+edge, and the content image in the right of the window will be updated
+to show the effect of the crop.
+</para>
+
+<para>
+The <guilabel>fade in</guilabel> and <guilabel>fade out</guilabel>
+settings can be used to apply linear fades into and out of a piece of
+content. Specify the time for each, clicking <guilabel>Set</guilabel>
+after making any changes.
+</para>
+
+<para>
+The <guilabel>Scale to</guilabel> option governs the shape that
+DCP-o-matic will scale the content's image into. Select the aspect
+ratio that your content should be presented in.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Video description</title>
+
+<para>
+At the bottom of the video tab is a short description of what will
+happen to your video with the current settings. In the example of
+<xref linkend="fig-video-tab"/>, DCP-o-matic is telling you that the
+video file is 2048x872 pixels and it has square pixels (a pixel
+aspect ratio of 1.00) hence its display aspect ratio is 2.35:1. Since
+the controls specify ‘2.35’ for the ratio, DCP-o-matic
+does not scale the image but pads it to the DCP's container ratio of
+1.85:1. For a 2K DCP this is 1998x1080 pixels.
+</para>
+
+<para>
+This description also gives the frame rate of the content and what
+will happen to it when it is played at the DCP's frame rate. See
+<xref linkend="ch-frame-rates"/> for details of DCP-o-matic's
+frame-rate conversion.
+</para>
+
+</section>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Audio</title>
+
+<para>
+The <guilabel>Audio</guilabel> tab controls properties of the sound, as shown in <xref linkend="fig-audio-tab"/>.
+</para>
+
+<figure id="fig-audio-tab">
+ <title>Audio settings tab</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/audio-tab&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<!-- ============================================================== -->
+<section>
+<title>The audio map</title>
+
+<para>
+The section at the bottom of the audio tab is the ‘audio
+map’. This governs how sound from the content will be arranged
+in the DCP.
+</para>
+
+<para>
+Down the left-hand side of the map is the list of audio channels in
+the currently-selected piece of content. These are labelled with two
+numbers; the first is the stream index within the content and the
+second is the channel number within that stream. Some content will
+have different streams for different languages or audio mixes. Along
+the top is each channel in the DCP. A green box means that the
+corresponding content channel will be copied into the corresponding
+DCP channel.
+</para>
+
+<para>
+When content channels are copied into DCP channels they can be done
+with variable gain. If, for example, you want to copy a channel
+as-is, you can set a gain of 0dB. Alternatively, if you want to mix
+two channels into one, you may want to use a gain of -6dB on each one
+to prevent clipping when the two channels are added.
+</para>
+
+<para>
+The green boxes of the audio mapping view tell you (very roughly) how
+much gain is applied to each channel. A full-height box means 0dB
+(i.e. unity) gain. Any less height indicates lower gain.
+</para>
+
+<para>
+To map one channel to another with 0dB gain, click in the empty box
+and it will turn green to reflect the mapping. A second click will
+turn the mapping back off. To set some other gain, right-click on the
+box to open the gain menu. This allows you to set
+<guilabel>Off</guilabel> (no mapping or negative infinity gain),
+<guilabel>Full</guilabel> (0dB gain), -6dB gain or
+<guilabel>Edit</guilabel> which allows you to set the required gain
+precisely.
+</para>
+
+<para>
+Consider, for example, the case in <xref linkend="fig-audio-map-eg1"/>.
+</para>
+
+<figure id="fig-audio-map-eg1">
+ <title>Audio map example 1</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/audio-map-eg1&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+Here, we have two channels in the source which are mapped to left and
+right, respectively, in the DCP. The full green boxes show that the
+mapping is at unity gain (0dB) in each case. Imagine that we modify
+the settings to those shown in <xref linkend="fig-audio-map-eg2"/>
+</para>
+
+<figure id="fig-audio-map-eg2">
+ <title>Audio map example 2</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/audio-map-eg2&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+We now have the content's streams mapped to left and right and also
+mixed together and placed in the DCP's centre channel. The smaller
+green boxes on the centre mappings show that those channels are added
+with some non-unity gain; you can see by hovering the mouse pointer
+over those boxes that the gain for content channels 1 and 2 is -6dB
+when being sent to the centre channel and 0dB when being sent to left
+and right.
+</para>
+
+<figure id="fig-audio-map-eg3">
+ <title>Audio map example 3</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/audio-map-eg3&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+As a final example, the map in <xref linkend="fig-audio-map-eg3"/>
+shows the mapping of a 5.1 source into a 5.1 DCP.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+ <title>Other controls</title>
+
+<para>
+The <guilabel>Use this DCP's audio as OV and make VF</guilabel>
+checkbox is only applicable if the selected content is an existing
+DCP. It allows you to make a VF DCP, using the audio content from the
+existing DCP by referencing it (rather than copying). See <xref
+linkend="sec-overlay"/>.
+</para>
+
+<para>
+<guilabel>Show graphs of audio levels</guilabel> will analyse the
+audio of the selected content and plot it on a graph. See <xref
+linkend="sec-show-audio"/> for more details.
+</para>
+
+<para>
+‘Audio Gain’ is used to alter the volume of the
+soundtrack. The specified gain (in dB) will be applied to each sound
+channel of your content before it is written to the DCP.
+</para>
+
+<para>
+If you use a sound processor that DCP-o-matic knows about, it can help
+you calculate changes in gain that you should apply. Say, for
+example, that you make a test DCP and find that you have to run it at
+volume 5 instead of volume 7 to get a good sound level in the screen.
+If this is the case, click the <guilabel>Calculate...</guilabel>
+button next to the audio gain entry, and the dialogue box in <xref
+linkend="fig-calculate-audio-gain"/> will open.
+</para>
+
+<figure id="fig-calculate-audio-gain">
+ <title>Calculating audio gain</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/calculate-audio-gain&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+For our example, put 5 in the first box and 7 in the second and click
+<guilabel>OK</guilabel>. DCP-o-matic will calculate the audio gain
+that it should apply to make this happen. Then you can re-make the
+DCP (this will be reasonably fast, as the video data will already have
+been done) and it should play back at the correct volume with 7 on
+your sound-rack fader.
+</para>
+
+<para>
+Current versions of DCP-o-matic only know about the Dolby CP650 and
+CP750. If you use a different sound processor, and know the gain
+curve of its volume control, <ulink url="mailto:carl@dcpomatic.com">get in
+touch</ulink>.
+</para>
+
+<para>
+<guilabel>Audio Delay</guilabel> is used to adjust the synchronisation
+between audio and video. A positive delay will move the audio later
+with respect to the video, and a negative delay will move it earlier.
+</para>
+
+</section>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Timed text (subtitles and closed captions)</title>
+
+<para>
+The timed text tab contains settings related to subtitles and closed captions in your
+content, as shown in <xref linkend="fig-timed-text-tab"/>.
+</para>
+
+<figure id="fig-timed-text-tab">
+ <title>Timed text settings tab</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/timed-text-tab&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+Depending on where timed text comes from it can sometimes be used as
+either an open subtitle (to be overlaid onto the cinema screen and
+seen by everybody) or as a closed caption (to be displayed to
+individual viewers using a special system such as the Doremi
+CaptiView™)
+</para>
+
+<para>
+DCP-o-matic can either:
+</para>
+
+<itemizedlist>
+ <listitem>Extract timed text that is embedded in video files, or</listitem>
+ <listitem>Use timed text from SubRip (<code>.srt</code>), SubStation
+ Alpha (<code>.ssa</code> or <code>.ass</code>) or DCP XML files. You may find the great
+ free program <ulink
+ url="http://www.nikse.dk/subtitleedit/">Subtitle Edit</ulink> useful
+ for creating such files.</listitem>
+</itemizedlist>
+
+<para>
+Embedded timed text is usually represented using a set of bitmaps,
+especially on files that have come from DVD or BluRay. Such text can
+be used as a subtitle, but not a closed caption (since the closed
+captioning system requires the text to be delivered as
+character codes rather than an image).
+</para>
+
+<para>In contrast, SubRip, SubStation Alpha or DCP text can be used as either a subtitle or a closed caption.</para>
+
+<para>
+With subtitles you have the further choice of whether to burn the
+subtitles into the image or include them as a separate subtitle
+‘asset’ within your DCP (in which case the projector
+overlays them onto the image on playback). The difference between
+burn-in and overlay is illustrated by <xref linkend="fig-burn-in"/>
+and <xref linkend="fig-discrete"/>.
+</para>
+
+<figure id="fig-burn-in">
+ <title>Burnt-in subtitles</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/burn-in&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<figure id="fig-discrete">
+ <title>Separate subtitles</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/discrete&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The advantage of separate subtitles is that the same video content can
+be used for DCPs in many different languages. This means that only a
+small text file needs to be changed for each target language, rather
+than a large video file. It also means that the time-consuming video
+encoding need only be done once for the project rather than once for
+every language.
+</para>
+
+<para>
+Select the <guilabel>Use as</guilabel> check-box to enable the timed
+text in the selected content, then choose what you want to use the
+text for: open subtitles or closed captions.
+</para>
+
+<para>
+Select the <guilabel>Burn subtitles into image</guilabel> check-box to
+burn subtitles into the image; if this is not ticked the
+subtitles will be included separately in the DCP to be rendered by the
+projector.
+</para>
+
+<para>
+The <guilabel>X Offset</guilabel> and <guilabel>Y Offset</guilabel>
+controls move subtitles around within the image. These controls have
+no effect for closed captions. The offsets are expressed as a
+percentage of the video frame size; 100% X offset is the entire width
+of the frame, and 100% Y offset is the entire height. Hence, to move
+the subtitles down by half the frame height you would use a Y offset
+of 50%.
+</para>
+
+<para>
+The <guilabel>X Scale</guilabel> and <guilabel>Y Scale</guilabel>
+controls scale subtitles. These controls have no effect for closed
+captions. Scale values of 1 make the subtitles the same size
+(relative to the size of the image) as they are on the original.
+Values lower than 1 make them smaller, and values higher make them
+larger. You can stretch the subtitles in either direction by
+specifying different values for X and Y scale. Subtitles from DVD and
+Blu Ray sources are frequently larger (relative to the video frame)
+than those typically used for DCP, so it is often useful to scale such
+subtitles down using these controls.
+</para>
+
+<para>
+The <guilabel>Line spacing</guilabel> control adjusts the line spacing
+of the subtitles. This only works for subtitles that did not come from bitmaps.
+</para>
+
+<para>
+The <guilabel>Stream</guilabel> control changes the subtitle stream
+that is used when the content has more than one.
+</para>
+
+<para>
+If you are using non-image (text) subtitles or closed captions you can see the
+subtitle text and timings by clicking the <guilabel>View...</guilabel>
+button, or specify the fonts that should be used by clicking <guilabel>Fonts...</guilabel>.
+</para>
+
+<para>
+With any subtitles you can click <guilabel>Appearance...</guilabel> to
+change how the subtitles look. Some of the controls in the
+<guilabel>Appearance</guilabel> only apply to burnt-in subtitles, as
+only limited control is available for subtitles rendered by the
+projection system.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Timing</title>
+
+<para>
+The timing tab contains settings related to the timing of your
+content, as shown in <xref linkend="fig-timing-tab-detail"/>.
+</para>
+
+<figure id="fig-timing-tab-detail">
+ <title>Timing settings tab</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/timing-tab&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+Most of the timing tab's entries are <emphasis>time-codes</emphasis>.
+These are expressed as four numbers, as shown in <xref
+linkend="fig-timecode"/>.
+</para>
+
+<figure id="fig-timecode">
+ <title>Timecode</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/timecode&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+<guilabel>Position</guilabel> is the time at which this piece of
+content should start within the DCP. In most cases, this will be
+<code>0:0:0:0</code> to make the content start at the beginning of the
+DCP.
+</para>
+
+<para>
+<guilabel>Full length</guilabel> is the length of the piece of
+content. This can only be set for still-image content: for video or
+sound content, it is fixed by the nature of the content file. If
+still-image content is being used you can set the length for which it
+should be displayed using this control.
+</para>
+
+<para>
+<guilabel>Trim from start</guilabel> specifies the amount that should
+be trimmed from the start of the content. You can set this amount to
+trim up to the current preview position by clicking <guilabel>Trim up
+to current position</guilabel>.
+</para>
+
+<para>
+<guilabel>Trim from end</guilabel> specifies the amount that should be
+trimmed from the end of the content. You can set this amount to trim
+after the current preview position by clicking <guilabel>Trim after to
+current position</guilabel>.
+</para>
+
+<para>
+<guilabel>Play length</guilabel> indicates how long this piece of
+content will be once the trims have been applied. This will be equal
+to the full length minus <guilabel>trim-from-start</guilabel> and minus <guilabel>trim-from-end</guilabel>.
+</para>
+
+<para>
+<guilabel>Video frame rate</guilabel> specifies the frame rate for
+still-image content. It can also be used to override the detected
+frame rate of other content if DCP-o-matic has got it wrong.
+</para>
+
+<para>
+Each timecode control has a <guilabel>Set</guilabel> which you should
+click when you have entered a new value for a timecode. The
+<guilabel>Set</guilabel> button will make DCP-o-matic take account of
+any changes to the corresponding timecode.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+ <title>Timeline</title>
+
+ <para>
+ The timeline window gives an overview of all the pieces of content
+ in your film, and how they are arranged. You can open the
+ timeline by clicking the <guilabel>Timeline...</guilabel> button
+ next to the content list. This will open a window like the one in <xref linkend="fig-timeline1"/>.
+ </para>
+
+ <figure id="fig-timeline1">
+ <title>Timeline</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/timeline1&scs;"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <para>
+ The horizontal axis represents time, and you can see the time codes (in
+ hours:minutes:seconds) along the bottom of the window. Pieces of
+ content are represented with rectangles in the main part of the
+ window. Content containing different types of data (e.g. a MP4
+ file with video, audio and subtitles) have a rectangle for each
+ type.
+ </para>
+
+ <para>
+ Within the timeline you can select content by clicking, and drag
+ it to change its position. Right-clicking a piece of content will
+ open the content menu.
+ </para>
+
+ <para>
+ The toolbar at the top of the window offers the following tools:
+ </para>
+
+ <itemizedlist>
+ <listitem>Select — to select and move content.</listitem>
+ <listitem>Zoom in — to drag out an area that you want to see more closely.</listitem>
+ <listitem>Zoom out — to zoom out so that the window shows the whole film.</listitem>
+ <listitem>Snap — when enabled, content will snap to other content when you drag it close.</listitem>
+ <listitem>Sequence — when enabled, content will be kept in sequence, without gaps, even if some content is removed.</listitem>
+ </itemizedlist>
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Video processing pipeline</title>
+
+<para>
+This section gives a little more detail about how DCP-o-matic process
+video as it takes it from a source and puts it into a DCP.
+</para>
+
+<para>
+Consider, as a somewhat over-the-top example, that we have a 720 x 576
+image which is letterboxed with 36 black pixels each at the top and
+bottom, and the video content within the letterbox should be presented
+in the DCP at ratio of 2.39:1 within a 1.85:1 frame (such as might
+happen with a trailer). The source image is shown in <xref
+linkend="fig-pipeline1"/>.
+</para>
+
+<figure id="fig-pipeline1">
+ <title>Example image to demonstrate video processing</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/pipeline1&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+DCP-o-matic runs through the following steps when preparing an image for a DCP:
+</para>
+
+<itemizedlist>
+<listitem>Crop</listitem>
+<listitem>Scale</listitem>
+<listitem>Place in container</listitem>
+</itemizedlist>
+
+<para>
+First, some amount of the image can be cropped. This is almost always
+used to remove black borders (letterboxing and/or pillarboxing) around
+images.
+</para>
+
+<para>
+In our example image, we would use 36 pixels of crop from the top and
+bottom. This would give the new image shown in <xref
+linkend="fig-pipeline2"/>.
+</para>
+
+<figure id="fig-pipeline2">
+ <title>Example image after cropping</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/pipeline2&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The next step is to scale the image. Since this content should be
+presented in a 2.39:1 (scope) aspect ratio inside a 1.85:1 (flat) DCP we would select
+<guilabel>Scope</guilabel> from the <guilabel>Scale to</guilabel>
+option in the <guilabel>Video</guilabel> tab and
+<guilabel>Flat</guilabel> from the <guilabel>Container</guilabel>
+option in the <guilabel>DCP</guilabel> tab.
+</para>
+
+<para>The <guilabel>Scale to</guilabel> option should always be set to
+the aspect ratio at which the content should be seen. The
+<guilabel>Container</guilabel> option should be set to the preset that
+you want to use on the projector. Of course, these two settings will
+often be the same.
+</para>
+
+<para>
+Given the scaling and container information, DCP-o-matic will look at
+the DCP's container size, and then scale the source image up until one
+or both of its dimensions (width, height or both) fits the size of the
+container, all the while preserving the desired aspect ratio.
+</para>
+
+<para>
+In our example here, the DCP's container is specified as 1.85:1 (so
+that the DCP will play back correctly using the projector's
+‘Flat’ preset). At 2K, 1.85:1 is 1998 pixels by 1080.
+Scaling the source up whilst preserving its 1.85:1 aspect ratio will
+result in the image hitting the sides of the container first, at a
+size of 1998 x 836. This gives us a new version of the image as shown
+in <xref linkend="fig-pipeline3"/>.
+</para>
+
+<figure id="fig-pipeline3">
+ <title>Example image after cropping and scaling</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/pipeline3&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The final step is to place the image into the DCP. In this case,
+since we have a 2.39:1 image that should be presented as a 1.85:1 DCP,
+we have set the <guilabel>container</guilabel> in the
+<guilabel>DCP</guilabel> tab to be Scope. Since the content has been
+scaled to 1998 x 836, and a Flat container is 1998 x 1080, there will
+be some black bars at the top and bottom of the image. DCP-o-matic
+shares out this black equally, as shown in <xref
+linkend="fig-pipeline3"/>.
+</para>
+
+<figure id="fig-pipeline4">
+ <title>Example image in the DCP</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="100" fileref="diagrams/pipeline4&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+</section>
+
+
+<section>
+ <title>Copy and paste settings</title>
+
+<para>
+Once you have set up a piece of content it is possible to copy the
+settings you have applied to another piece of content. To do this,
+select the content to copy from and choose <guilabel>Copy</guilabel>
+from the <guilabel>Edit</guilabel> menu. Then select the content to
+copy to and choose <guilabel>Paste</guilabel>. A dialogue box will
+open to allow you to choose which settings you want to copy. Clicking
+<guilabel>OK</guilabel> will apply the copied settings.
+</para>
+
+</section>
+
+
+<section>
+<title>Advanced content settings</title>
+
+<para>
+There are a few more content settings that you can change by right-clicking a piece of content in the list and choosing <guilabel>Advanced settings...</guilabel>
+This opens the dialogue box shown in <xref linkend="fig-advanced-content"/>.
+</para>
+
+<figure id="fig-advanced-content">
+ <title>Advanced content dialogue</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/advanced-content&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Video filters</title>
+
+<para>
+The <guilabel>Video filters</guilabel> setting allows you to apply various
+filters to the image. These may be useful to try to improve
+poor-quality sources like DVDs. You can set up the filters by clicking the
+<guilabel>Edit</guilabel> button next to the filters entry; this opens the filters selector
+as shown in <xref linkend="fig-filters"/>.
+</para>
+
+<figure id="fig-filters">
+ <title>Filters selector</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/filters&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+</section>
+
+
+<section>
+<title>Override frame rate</title>
+
+<para>
+The <guilabel>Override detected video frame rate</guilabel> setting has some different effects depending on the type of content
+you use it on.
+</para>
+
+<para>
+For video content, it sets the frame rate that DCP-o-matic will run the video at. This is useful if DCP-o-matic has mis-detected
+the video frame rate. For example, if DCP-o-matic says your content is 24fps when you know for a fact it's 25fps, you can set the
+override value to 25 to force DCP-o-matic to do the right thing.
+</para>
+
+<para>
+On audio, subtitle and caption content this setting behaves slightly differently. It sets the video frame rate that the content
+in question was intended to work with. As an example, consider a project with a 23.976fps video source and some separate audio files.
+Perhaps those audio files have been mastered alongside a 24fps version of your video. By default, DCP-o-matic will see the 23.976fps
+video file and decide to run it slightly fast at 24fps to fit the DCP standard. It will then also run the audio slightly fast so that
+it stays in sync with the video.
+</para>
+
+<para>
+In this case, though, that is not what you want, since the audio is already ‘fixed’ to work alongside 24fps video. If you
+override the video frame rate of the <emphasis>audio</emphasis> content to 24fps this will stop DCP-o-matic altering it.
+</para>
+
+<para>
+A similar situation can occur if you have video at one rate and a subtitle file that was prepared with its timing at a different rate.
+In that case, you should override the video frame rate of the <emphasis>subtitle</emphasis> content to the one that it was prepared for.
+This will mean that DCP-o-matic can get the relative timing right.
+</para>
+
+<para>
+Do <emphasis>not</emphasis> use this setting to change the DCP frame rate. Doing so will result in strange effects and sync problems.
+</para>
+</section>
+
+
+<section>
+<title>Video has burnt-in subtitles</title>
+<para>
+Details about subtitle language are stored in various places within the DCP metadata. If a piece of video content already has subtitles
+burnt into the image you can tell DCP-o-matic the language that they are in by clicking the <guilabel>Edit...</guilabel> button.
+</para>
+</section>
+
+
+<section>
+<title>Ignore this content's video</title>
+<para>
+Tick this if you have some content which includes video along with other things (such as audio or subtitles) and you do
+<emphasis>not</emphasis> want the video to appear in the DCP.
+</para>
+</section>
+
+
+</section>
+
+</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. 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>
+
+The up-mixers are not particularly advanced and should be used with care. You are strongly advised to check how the DCPs sound in a cinema if you have used one of DCP-o-matic's upmixers.
+
+<!-- ============================================================== -->
+<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 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 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. Higher quality files will, of course, be larger.
+ </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 an attacker 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, yielding the magic
+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>
+
+<para>
+It can be inconvenient to need a whole DCP-o-matic project just to
+create KDMs for its film. Perhaps you want to archive the project to
+save space, or create KDMs on a different machine. In such situations
+it is easier to use a DKDM. This is a normal KDM, but instead of
+being targeted at a projection system (to allow it to decrypt the
+content) it is targeted at a particular user's certificate. This
+means that the certificate owner can create new KDMs for other users.
+The DKDM holds everything that is required to create further KDMs.
+</para>
+
+<para>
+Sometimes it is useful to create DKDMs that can be used by
+DCP-o-matic. If you create such a DKDM you can keep it and then, at
+any point in the future, use DCP-o-matic's standalone KDM creator to
+make KDMs for the DKDM's film for any cinema.
+</para>
+
+<para>
+In other cases a DKDM is sent to a 3rd party so that they can create
+KDMs for your films. This can be useful if, for example, you have a
+distributor who provides 24-hour KDM support to cinemas and can create
+KDMs for anybody that requires them at short notice.
+</para>
+
+<para>
+To create a DKDM for DCP-o-matic, open your encrypted project and
+select <guilabel>Make DKDM for DCP-o-matic...</guilabel> from the
+<guilabel>Jobs</guilabel> menu. Select the CPL that you want to make
+the DKDM for and click <guilabel>OK</guilabel>. This DKDM will then
+be available in the KDM creator. This is a separate program which you
+can start from the same place that you start the ‘normal’
+DCP-o-matic. Its window is shown in <xref linkend="fig-kdm-creator"/>.
+</para>
+
+<figure id="fig-kdm-creator">
+ <title>The KDM creator</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata scale="30" fileref="screenshots/kdm-creator&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+To create KDMs, select the cinema(s) and/or screens that you want KDMs
+to be created for, the date range, the DCP that the KDMs are for and
+the destination for the KDMs and click <guilabel>Create
+KDMs</guilabel>.
+</para>
+
+<para>
+By default the <guilabel>DKDM</guilabel> list will list any DCPs for
+which you have clicked <guilabel>Make DKDM for
+DCP-o-matic</guilabel> in the main DCP-o-matic program. If you have
+other DKDMs you can add them by clicking <guilabel>Add...</guilabel> and
+specifying the file containing the DKDM.
+</para>
+
+<para>
+If another organisation wants to send you a DKDM they will ask you for
+a target certificate. You can get DCP-o-matic's target certificate by
+opening <guilabel>Preferences</guilabel> and clicking <guilabel>Export
+DCP decryption certificate...</guilabel> in the <guilabel>Keys</guilabel>
+tab.
+
+</para>
+
+</section>
+
+<section>
+<title>Encryption keys</title>
+
+<para>
+ You must be careful when using encryption not to lose important keys.
+</para>
+
+<para>
+If you are making KDMs from a DCP-o-matic film you
+<emphasis>must</emphasis> ensure that you have a backup of the
+<code>metadata.xml</code> file from the project, as well as the DCP
+itself.
+</para>
+
+<para>
+If you are using a DKDM you <emphasis>must</emphasis> ensure that you
+have a backup of DCP-o-matic's <code>config.xml</code> file, since it
+contains the only key which can decrypt the DKDM. The
+<code>config.xml</code> file location depends on your operating
+system; possible locations are listed in <xref linkend="ch-config"/>.
+</para>
+
+</section>
+
+<section>
+ <title>Should I encrypt?</title>
+
+ <para>
+ The question of whether encryption is appropriate for a given
+ project is a tricky one.
+ </para>
+
+ <para>
+ On the one hand, if you distribute an unencrypted DCP it is easy for
+ anybody to take it and do whatever they want with its contents.
+ They could use DCP-o-matic to convert it to a MP4, show it in
+ their cinema, or even edit and redistribute it in ways that you
+ do not like.
+ </para>
+
+ <para>
+ Encryption prevents this, but brings its own problems. It will be
+ impossible for a cinema to screen your DCP unless they have the
+ correct KDM. This is easy enough if things work as they should,
+ but problems can occur. For example, cinemas may substitute
+ broken playout servers with new ones without telling you: then the
+ KDM that you sent them will be invalid, and a new one required.
+ If the cinema can't get in touch with you, or somebody else who
+ can create a new KDM, they can't screen your DCP. Often these
+ problems are only discovered very close to showtime, with little
+ time for fixes.
+ </para>
+
+ <para>
+ If you are distributing encrypted DCPs widely it is worth thinking
+ about who will make the KDMs, and who will provide quick-response
+ technical support. It may be a good idea to engage a company who can
+ provide such services.
+ </para>
+
+</section>
+
+
+<section>
+<title>Encryption overview</title>
+
+<figure id="fig-encryption-overview">
+ <title>Overview of encryption</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="diagrams/crypt&dia;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+</section>
+</chapter>
+
+
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-preferences" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+<title>Preferences</title>
+
+<para>
+DCP-o-matic provides preferences which can be used to modify its
+behaviour. They are described in this chapter.
+</para>
+
+<para>
+Preferences can be edited by choosing
+<guilabel>Preferences...</guilabel> from the <guilabel>Edit</guilabel>
+menu. This opens a dialogue which is split into eleven tabs.
+</para>
+
+<!-- ============================================================== -->
+<section>
+<title>General</title>
+
+<para>
+The general tab is shown in <xref linkend="fig-prefs-general"/>.
+</para>
+
+<figure id="fig-prefs-general">
+ <title>General preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-general&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Language</title>
+
+<para>
+If you tick the <guilabel>Set Language</guilabel> checkbox and choose
+a language from the list, that language will be used for DCP-o-matic.
+You will need to restart DCP-o-matic to see the new language.
+</para>
+
+<para>
+The translations for DCP-o-matic have been contributed by helpful
+users. If your language is not on the last, head to <ulink
+url="https://dcpomatic.com/i18n.php">the DCP-o-matic website</ulink> to
+find out how to contribute a translation.
+</para>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+ <title>Interface complexity</title>
+
+ <para>
+ Choose <guilabel>Simple</guilabel> to see a cut-down, simplified
+ interface or <guilabel>Full</guilabel> to see DCP-o-matic's full
+ interface.
+ </para>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Number of threads DCP-o-matic should use</title>
+
+<para>
+When DCP-o-matic is encoding DCPs it can use multiple parallel threads
+to speed things up. Set this value to the number of threads
+DCP-o-matic should use. This should normally be the number of
+processors (or processor cores) in your machine. DCP-o-matic will try
+to set this up correctly when you run it for the first time.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Number of threads DCP-o-matic encode server should use</title>
+
+<para>
+This is the number of threads that the encode server should use when
+it is running and helping another copy of DCP-o-matic to speed up its
+encode.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Configuration file</title>
+
+<para>
+This is the location of DCP-o-matic's configuration file on disk. You
+can use this to share configuration between several copies of
+DCP-o-matic, across a network share, for instance.
+</para>
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Cinema and screen database file</title>
+
+<para>
+This option allows you to change the file that DCP-o-matic uses to
+store details of the cinemas and screens used to make KDMs.
+</para>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Play sound via</title>
+
+<para>
+The checkbox to the left of <guilabel>Play sound</guilabel> enables or
+disables DCP-o-matic use of sound. On some machines there will be
+multiple options in the drop-down menu to decide how the sound should
+be played.
+</para>
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Integrated loudness</title>
+
+<para>
+If <guilabel>Find integrated loudness, true peak and loudness range
+when analysing audio</guilabel> is ticked, DCP-o-matic will do extra
+work when analysing audio. Leave this ticked if the extra parameters
+are useful to you. If not, untick it and audio analysis will be
+faster.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Automatically analyse content audio</title>
+
+<para>
+If this checkbox is ticked an audio analysis will be run whenever content is added that contains sound.
+</para>
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Updates</title>
+
+<para>
+The <guilabel>Check for updates on startup</guilabel> option, if
+enabled, will tell DCP-o-matic to check on <ulink
+url="https://dcpomatic.com/">dcpomatic.com</ulink> to see if there any
+newer versions of DCP-o-matic then the one you are running. If so, a
+dialogue box will open with a link to download the new version.
+</para>
+
+<para>
+The <guilabel>Check for testing updates as well as stable
+ones</guilabel> option will also check for test updates as well as
+those that are formally ‘released’. This is useful if you
+like to live on the bleeding edge!
+</para>
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Issuer and creator</title>
+
+<para>
+With these controls you can set the issuer and creator strings that
+will be put into the DCPs which you create. The issuer is typically your name
+(or your organisation's name) and the creator is typically the name of the tool
+used to make the DCP (e.g. DCP-o-matic).
+</para>
+</section>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Defaults</title>
+
+<para>
+The defaults tab is shown in <xref linkend="fig-prefs-defaults"/>.
+</para>
+
+<figure id="fig-prefs-defaults">
+ <title>Defaults preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-defaults&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+The options in this tab simply allow you to set up default values for
+various properties of new films.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Servers</title>
+
+<para>
+The servers tab is shown in <xref linkend="fig-prefs-servers"/>.
+</para>
+
+<figure id="fig-prefs-servers">
+ <title>Servers preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-servers&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+If <guilabel>Use all servers</guilabel> is ticked DCP-o-matic will
+locate encoding servers automatically (see <xref
+linkend="ch-servers"/>).
+</para>
+
+<para>
+Instead of this (or in addition) servers can be specified explicitly.
+To add a server, click <guilabel>Add...</guilabel> and enter the host
+name or IP address of the server to use.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section xml:id="sec-prefs-keys">
+<title>Keys</title>
+
+<para>
+The Keys tab (shown in <xref linkend="fig-prefs-keys"/>) has controls
+related to the keys and certificates used in some parts of DCP
+creation.
+</para>
+
+<figure id="fig-prefs-keys">
+ <title>Keys preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-keys&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+<guilabel>Export KDM decryption certificate...</guilabel> allows you
+to save the certificate that DCP-o-matic uses when decrypting KDMs
+that you give it. Use this option if somebody wants to make a KDM for
+you and asks for your certificate.
+</para>
+
+<para>
+<guilabel>Export all KDM decryption settings...</guilabel> exports a
+file which contains all the DCP-o-matic settings related to the use of
+KDMs supplied by other people. Use this button and <guilabel>Import
+all KDM decryption settings...</guilabel> to transfer settings between
+different copies of DCP-o-matic so that they can both use the same
+KDMs.
+</para>
+
+<para>
+The two <guilabel>Advanced...</guilabel> buttons open advanced
+dialogue boxes for detailed manipulation of DCP-o-matic's certificate
+chains.
+</para>
+
+</section>
+
+<section>
+<title>Advanced keys settings</title>
+
+<para>
+At the top of the <guilabel>Advanced</guilabel> dialogue for signing
+DCPs and KDMs is the chain of certificates that will be used to sign
+DCPs and KDMs. DCP-o-matic creates a random chain when you first run
+it and if you are happy to use this chain you can ignore the
+preferences. Otherwise, you can add or remove certificates from the
+chain using the <guilabel>Add...</guilabel> and
+<guilabel>Remove</guilabel> buttons.
+</para>
+
+<para>
+If you want DCP-o-matic to re-create the certificate chain (using new,
+random certificates) click <guilabel>Re-make
+certificates and key...</guilabel> and specify your organisation and common
+names in the dialogue box that opens.
+</para>
+
+<para>
+Underneath the certificate chain is the private key that corresponds
+to the leaf certificate in the chain. You can specify your own
+private key by clicking <guilabel>Import...</guilabel>. You must do
+this if you change the leaf certificate, so that the leaf private key
+corresponds to the public key held in the leaf certificate.
+</para>
+
+<para>
+At the top of the <guilabel>Advanced</guilabel> dialogue for decrypting DCPs is the chain and key which is used by
+DCP-o-matic when you import an encrypted DCP as a piece of content.
+The leaf certificate of this chain contains the public key that should
+be used when targeting a KDM at DCP-o-matic.
+</para>
+
+<para>
+Clicking <guilabel>Export chain...</guilabel> will
+export the whole certificate chain.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section xml:id="sec-prefs-tms">
+<title>TMS</title>
+<titleabbrev xml:id="sec-prefs-tms-short">TMS preferences</titleabbrev>
+
+<para>
+The TMS tab (shown in <xref linkend="fig-prefs-tms"/>) gives some
+options for specifying details about your theatre management system
+(TMS). If you do this, and your TMS accepts SSH or FTP connections,
+you can upload DCPs directly from DCP-o-matic to the TMS using the
+<guilabel>Send DCP to TMS</guilabel> option in the
+<guilabel>Jobs</guilabel> menu.
+</para>
+
+<figure id="fig-prefs-tms">
+ <title>TMS preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-tms&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+<guilabel>Protocol</guilabel> should be set to SCP or FTP as
+appropriate for your TMS. We know that the Arts Alliance Media (AAM)
+and the Doremi ranges uses SCP connections, and that Dolby's TMSs use
+FTP. Do let us know if you use any other type of TMS with the
+<guilabel>Send DCP to TMS</guilabel> feature.
+</para>
+
+<para>
+<guilabel>TMS IP address</guilabel> should be set to the IP address of
+your TMS, <guilabel>TMS target path</guilabel> to the place that DCPs
+should be uploaded to (which will be relative to the home directory of
+the SSH or FTP user). Finally, the user name and password are the
+credentials required to log into the TMS via SSH or FTP.
+</para>
+
+<para>
+Note that for this to work on Doremi servers you will need to set the
+<code>PasswordAuthentication</code> option in your server's
+<code>sshd_config</code> to <code>yes</code>.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Email</title>
+
+<para>
+The Email tab is shown in <xref linkend="fig-prefs-email"/>.
+</para>
+
+<figure id="fig-prefs-email">
+ <title>Email preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-email&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+These settings are used when DCP-o-matic sends emails.
+</para>
+
+<para>
+ <guilabel>Outgoing mail server</guilabel> should be the host name of a mail (SMTP) server that DCP-o-matic can use. You can also specify the port that DCP-o-matic should use. <guilabel>User name</guilabel> and <guilabel>Password</guilabel> are the credentials that are required to send email through the server you have specified.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>KDM email</title>
+
+<para>
+The KDM email tab is shown in <xref linkend="fig-prefs-kdm-email"/>.
+</para>
+
+<figure id="fig-prefs-kdm-email">
+ <title>KDM email preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-kdm-email&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+This is a template for the email that is used to send KDMs out to
+cinemas. You can change it to say whatever you like. A few
+‘magic’ strings will be replaced by information from the
+KDM that is being sent; these strings are shown in <xref linkend="tab-kdm-magic"/>.
+</para>
+
+<table id="tab-kdm-magic">
+<title>‘Magic’ KDM strings</title>
+<tgroup cols='2' align='left' colsep='1' rowsep='1'>
+<tbody>
+<row>
+<entry><code>$CPL_NAME</code></entry><entry>DCP title</entry>
+</row>
+<row>
+<entry><code>$CINEMA_NAME</code></entry><entry>Cinema name</entry>
+</row>
+<row>
+<entry><code>$SCREENS</code></entry><entry>Name of screen or screens that KDMs are being generated for</entry>
+</row>
+<row>
+<entry><code>$START_TIME</code></entry><entry>The time from which the KDMs are valid</entry>
+</row>
+<row>
+<entry><code>$END_TIME</code></entry><entry>The time until which the KDMs are valid</entry>
+</row>
+</tbody>
+</tgroup>
+</table>
+
+<para>
+The <guilabel>Reset to default text</guilabel> will replace the current KDM email with DCP-o-matic's default.
+</para>
+
+</section>
+
+<!-- ============================================================== -->
+<section>
+<title>Notifications</title>
+
+<para>
+The Notifications tab is shown in <xref linkend="fig-prefs-notifications"/>.
+</para>
+
+<figure id="fig-prefs-notifications">
+ <title>Notifications preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-notifications&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+DCP-o-matic can notify the user when jobs have completed. These
+notifications can be either or both of a message box on-screen (if
+<guilabel>Message box</guilabel> is ticked) and email (if
+<guilabel>Email</guilabel> is ticked). If you enable email
+notifications you can fill in the details of the emails you want to
+send.
+</para>
+
+<para>
+The bottom box in the tab is the contents of the email that should
+be sent. DCP-o-matic will replace the ‘magic’ strings
+<code>$JOB_NAME</code> and <code>$JOB_STATUS</code> in the with the
+details of the job that has completed.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Cover sheet</title>
+
+<para>
+The DCP cover sheet configuration is shown in <xref linkend="fig-prefs-cover-sheet"/>.
+</para>
+
+<figure id="fig-prefs-cover-sheet">
+ <title>DCP cover sheet preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-cover-sheet&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+This is a template for the cover sheet that is written next to every DCP that DCP-o-matic creates. You can change it to say whatever you like. A few
+‘magic’ strings will be replaced by information from the
+DCP that has been made:
+</para>
+
+<table>
+<title>‘Magic’ cover sheet strings</title>
+<tgroup cols='2' align='left' colsep='1' rowsep='1'>
+<tbody>
+<row>
+<entry><code>$CPL_NAME</code></entry><entry>DCP title</entry>
+</row>
+<row>
+<entry><code>$TYPE</code></entry><entry>DCP content type (e.g. feature, trailer...)</entry>
+</row>
+<row>
+<entry><code>$CONTAINER</code></entry><entry>The container ratio (e.g. flat, scope...)</entry>
+</row>
+<row>
+<entry><code>$AUDIO</code></entry><entry>Details of the audio channels</entry>
+</row>
+<row>
+<entry><code>$AUDIO_LANGUAGE</code></entry><entry>Audio language</entry>
+</row>
+<row>
+<entry><code>$SUBTITLE_LANGUAGE</code></entry><entry>Subtitle language</entry>
+</row>
+<row>
+<entry><code>$LENGTH</code></entry><entry>DCP length in hours, minutes and seconds</entry>
+</row>
+<row>
+<entry><code>$SIZE</code></entry><entry>DCP size in gigabytes</entry>
+</row>
+</tbody>
+</tgroup>
+</table>
+
+<para>
+The <guilabel>Reset to default text</guilabel> will replace the current cover sheet with DCP-o-matic's default.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section xml:id="sec-prefs-advanced">
+<title>Advanced</title>
+<titleabbrev xml:id="sec-prefs-advanced-short">Advanced preferences</titleabbrev>
+
+<para>
+The advanced preferences are shown in <xref linkend="fig-prefs-advanced"/>.
+</para>
+
+<figure id="fig-prefs-advanced">
+ <title>Advanced preferences</title>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="screenshots/prefs-advanced&scs;"/>
+ </imageobject>
+ </mediaobject>
+</figure>
+
+<para>
+<guilabel>Maximum JPEG2000 bandwidth</guilabel> specifies the maximum
+bit-rate of JPEG2000 that DCP-o-matic will allow you to create. You
+are advised to leave this at 250Mbit/s in normal use for maximum DCP
+compatibility.
+</para>
+
+<para>
+<guilabel>Allow any DCP frame rate</guilabel> removes the limits on
+the DCP video frame rates that DCP-o-matic will create. This may be
+useful for experimentation. Again, you are strongly advised to leave
+this unticked for normal use.
+</para>
+
+<para>
+<guilabel>Only servers encode</guilabel> makes DCP-o-matic encode
+JPEG2000 data only on encoding servers and not on the host. We
+suggest you leave this unticked unless you have a good reason to do otherwise.
+</para>
+
+<para>
+With the filename format fields you can adjust the filenames that are
+used for metadata (CPL and PKL files) and assets (MXF and subtitle
+files). Below each field there is a list of the ‘magic’
+values that you can use in the format and an example of a filename
+that you might see with your current settings.
+</para>
+
+<para>
+The four checkboxes labelled <guilabel>Log</guilabel> control what
+sort of messages DCP-o-matic writes to its log file when creating a
+DCP. It is useful to leave <guilabel>General</guilabel>,
+<guilabel>Warnings</guilabel> and <guilabel>Errors</guilabel> ticked
+as this makes the log files useful for tracking down bugs.
+</para>
+
+<para>
+The <guilabel>Timing</guilabel> checkbox will enable extra log entries
+to allow developers to investigate and optimise the speed of
+DCP-o-matic. It will significantly increase the size of the log files
+that are generated, so in normal use it is best to leave this
+unticked.
+</para>
+
+</section>
+</chapter>
+
+<chapter xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en" xml:id="ch-frame-rates">
+<title>Frame rates</title>
+
+<para>
+In an ideal world, a DCP would be created using content at the same
+video frame and audio sampling rates as the DCP. This is not,
+however, always possible.
+</para>
+
+
+<!-- ============================================================== -->
+<section>
+<title>DCP frame rate limitations</title>
+
+<para>
+There are some limitations to video and audio frame rates in DCPs. This is
+complicated by the fact that not all projectors will play DCPs at the
+same frame rates. It is possible to create a DCP which one projector will
+play fine, but another (of a different type) will refuse to play.
+</para>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Guaranteed rates</title>
+
+<para>
+The only rates that are guaranteed to work on all DCI projectors are
+24 frames per second (fps) for video and 48kHz for audio. If you are
+sending DCPs to unknown places it is wise to consider using these
+rates if at all possible.
+</para>
+
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Other often-supported rates</title>
+<para>
+Many projectors now in the wild support additional video frame rates:
+25, 30, 48, 50 and 60 fps.
+</para>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Adapting content to fit the DCP rate</title>
+
+<para>
+DCP-o-matic has a few tricks to allow you to use content that is not
+in one of the ‘approved’ rates.
+</para>
+
+<para>
+Audio is easy: DCP-o-matic can resample to 48kHz from any source rate
+with minimal loss in quality.
+</para>
+
+<para>
+Video rate conversion is harder. DCP-o-matic's basic strategy to deal
+with a non-supported content rate is to run it at the wrong speed, and
+to adjust the audio to keep it in sync.
+</para>
+
+<para>Let us consider the example of a 25fps source for which you want
+to create a 24fps DCP. DCP-o-matic will put the frames from the
+source directly into the DCP without modification, but will tell the
+projector to play them back at 24fps. This means that the DCP's video
+will run slightly slower than the original.
+</para>
+
+<para>
+If DCP-o-matic did nothing else, the result of this would be that the
+audio would be running at the original speed with the video running
+slowly. Hence the audio would drift slowly out of sync. To avoid
+this, DCP-o-matic also resamples the audio such that the projector
+will play it too slow by the same amount. Hence it will sound
+slightly different but will remain in sync with the video.
+</para>
+
+<para>
+For very low or high frame rates, DCP-o-matic can also skip or duplicate frames.
+</para>
+
+</section>
+</section>
+
+
+<!-- ============================================================== -->
+<section>
+<title>Setting up</title>
+
+<para>
+The <guilabel>Frame Rate</guilabel> control in the
+<guilabel>DCP</guilabel> tab sets the video frame rate that the DCP
+will use. Clicking <guilabel>Use best</guilabel> sets the rate to
+what DCP-o-matic thinks is the best for your content. With this
+button, DCP-o-matic assumes that the most commonly-working frame rates (24,
+25 and 30fps) are allowed.
+</para>
+
+<para>
+After this, the <guilabel>Video</guilabel> tab for each piece of
+content will give a summary of what DCP-o-matic is doing with that
+content.
+</para>
+
+<para>
+If you want to experiment with other non-standard frame rates, you can
+do so by ticking the <guilabel>Allow any DCP frame rate</guilabel> in
+the <guilabel>Advanced</guilabel> tab of the preferences dialogue (see the
+<xref linkend="sec-prefs-advanced" endterm="sec-prefs-advanced-short"/>). You are strongly advised to
+use this only on your own equipment, and only for experimentation
+purposes.