Steinberg Nuendo 4 Manual

							461
Synchronization
Synchronization
Before you proceed, you need to make sure that the clock 
signals on your ASIO cards are synchronized correctly. 
This is essential when cabling any kind of digital audio 
system, not just VST System Link.
The Clock Mode or Sync Mode is set up in the ASIO con-
trol panel of the audio hardware. Proceed as follows:
1.Pull down the Devices menu and open the Device Set-
up dialog.
2.On the VST Audio System page, select your audio in-
terface from the “ASIO Driver” pop-up menu.
In the Devices List, the name of the audio interface is displayed below 
the VST Audio System entry.
3.Select your audio interface in the Devices list to the 
left.
4.Click the Control Panel button.
The ASIO control panel appears.
5.Open the ASIO control panel on the other computer 
as well.
If you are using another VST System Link host application on that com-
puter, check its documentation for details on how to open the ASIO con-
trol panel.
6.Now, you need to make sure that one audio card (and 
only one!) is set to be the Clock Master, and all the other 
cards are set to listen for the clock signal coming from the 
Clock Master i.e. they must be Clock Slaves.
The naming and procedure for this differs depending on the audio hard-
ware – consult its documentation if required. If you are using Steinberg 
Nuendo ASIO hardware, all cards default to the “AutoSync” setting – in 
this case you must set one of the cards (and only one) to “Master” in the 
Clock Mode section of the control panel.
Typically, the ASIO control panel for an audio card con-
tains some indication of whether the card receives a proper 
sync signal or not, and the sample rate of that signal.
This is a good indication that you have connected the cards and set up 
clock sync properly. Check your audio hardware’s documentation for de-
tails.
The only exception to this procedure is if you are using an 
external clock – which could be from a digital mixing desk 
or special Word Clock synchronizer for example. If so, you 
must leave all your ASIO cards in Clock Slave or Auto-
Sync mode, and make sure that each of them is listening 
for the signal coming from the synchronizer, usually 
passed through your ADAT cables or Word Clock con-
nectors in a daisy chain fashion.
VST System Link and latency
The general definition of latency is the amount of time it 
takes any system to respond to whatever messages are 
sent to it. For example, if your system’s latency is high and 
you play VST instruments in real time, you will get a no-
ticeable delay between when you press a key and when 
you hear the sound of the VST instrument. Nowadays, 
most ASIO-compatible audio cards are capable of operat-
ing with very low latencies. Also, all VST applications are 
designed to compensate for latency during playback, 
making the playback timing tight.
However, the latency time of a VST System Link network 
is the total latency of all the ASIO cards in the system 
added together. Therefore it’s extra important to minimize 
the latency times for each computer in the network.
ÖThe latency does not affect the synchronization – its 
always perfectly in time. But it can affect the time it takes 
to send and receive MIDI and audio signals, or make the 
system seem sluggish.
To adjust the latency of a system, you adjust the size of the 
buffers in the ASIO control panel – the lower the buffer 
size, the lower the latency. It’s best to keep to fairly low la-
tencies (buffer sizes) if your system can handle it – about 
12 ms or less is usually a good idea.
!All digital audio cables by definition always carry a 
clock signal as well as audio signals, so you dont 
have to use a special Word Clock input and output 
for this (although you may find that you get a slightly 
more stable audio system if you do, especially when 
using multiple computers).!It’s very important that one and only one card is the 
clock master, otherwise the network cannot function 
correctly. Once you have set this up, all the other 
cards in the network will take their clock signal from 
this card automatically. 
						

							462
Synchronization
Setting up your software
Now it’s time to set up your programs. The procedures 
below describe how to set things up in Nuendo; if you are 
using another program on the other computer, please re-
fer to its documentation.
Setting the sample rate
The projects in both programs must be set to use the 
same sample rate. Select “Project Setup…” from the 
Project menu and make sure the sample rate is the same 
in both systems.
Streaming digital audio between applications
1.Create input and output busses in both applications 
and route these to the digital inputs and outputs.
The number and configuration of the busses depends on your audio hard-
ware and on your needs. If you have a system with eight digital i/o channels 
(such as an ADAT connection), you could create several stereo or mono 
busses or a surround bus together with a stereo bus, or any combination 
you need. The important thing is that you should have the same configura-
tion in both applications – if you have four stereo output busses on com-
puter 1, you want four stereo input busses on computer 2, etc.
2.Set things up so that computer 1 plays back some au-
dio.
You could for example import an audio file and play this back in Cycle 
mode.
3.In the Inspector or mixer, make sure the playing audio 
channel is routed to one of the digital output busses you 
set up.
4.In computer 2, open the mixer and locate the corre-
sponding digital input bus.
The audio being played back should now “appear” in the program run-
ning on computer 2. You should see the input bus level meters moving.
5.Reverse this procedure so that computer 2 plays back 
and computer 1 “listens”.
Now you have verified that the digital connection works as 
it should.
ÖFrom this point on in this chapter, we refer to the bus-
ses connected to the digital inputs and outputs as “VST 
System Link busses”.
Settings for the audio hardware
When you send VST System Link data between comput-
ers, it is important that the digital information isn’t changed 
in any way between the programs. Therefore, you should 
open the control panel (or additional application) for your 
audio hardware and make sure that the following condi-
tions are met:
If there are additional “format settings” for the digital 
ports that you use for VST System Link data, make sure 
these are turned off.
For example, if you are using an S/PDIF connection for VST System Link, 
make sure that “Professional format”, Emphasis and Dithering are turned 
off.
If your audio hardware has a mixer application allowing 
you to adjust the levels of digital inputs and outputs, make 
sure that this mixer is disabled or that the levels for the 
VST System Link channels are set to (± 0 dB).
Similarly, make sure no other forms of DSP (pan, ef-
fects, etc.) are applied to the VST System Link signal.
Notes for Hammerfall DSP users
If you are using RME Audio Hammerfall DSP audio hard-
ware, the Totalmix function allows for extremely complex 
signal routing and mixing in the audio hardware. This can 
in some situations lead to “signal loops” in which case the 
VST System Link won’t work. If you want to make abso-
lutely sure this won’t cause any problems, select the de-
fault or “plain” preset for the Totalmix function. 
						

							463
Synchronization
Activating VST System Link
Before you proceed you need to make sure that VST Sys-
tem Link is set as Timecode Source in the Synchronization 
dialog and that the desired Sync options are activated, 
see “Timecode Preferences” on page 454.
After setting up the inputs and outputs, you now need to 
define which input/output should carry the actual VST 
System Link information.
The System Link networking signal is carried on only one 
bit of one channel. This means that if you have an ADAT 
based system which normally carries eight channels of 
24-bit audio, once you activate VST System Link you will 
have seven channels of 24-bit audio and one channel of 
23-bit audio (the least significant bit of this last channel 
will be used for networking). In practice this makes no dis-
cernible difference to the audio quality, since you will still 
have around 138dB headroom on this channel.
To set things up, open the VST System Link panel:
1.Open the Device Setup dialog on the Devices menu.
2.Select VST System Link in the Devices list to the left.
3.Use the ASIO Input and ASIO Output pop-up menus 
to define which channel should be the networking channel 
(and thus become a 23-bit audio channel, in our example).
Quite often you will be able to leave these pop-ups the way they are. 
4.Click the Active checkbox at the top of the panel.
5.Repeat the steps above for every computer on the net-
work. As the computers are made active, you should see the 
small Transmitting and Receiving indicators flashing on 
each active computer, and the name of each computer 
should appear in the list at the bottom of the pane. Each 
computer is assigned a random number – dont worry 
about this, its just so the network knows internally which 
one is which.
You can double-click on the name in bold (which is the 
name of the computer you’re currently working on) and set 
it to whatever other name you wish.
This name will appear in the System Link window of every computer on 
the network.
ÖIf you dont see the name of each computer appearing 
once you have made it active, you may have to check your 
settings. 
Go through the procedure above again and make sure that all ASIO 
cards are listening to the digital clock signals correctly, and that each 
computer has the correct inputs and outputs assigned to the System 
Link network.
Putting the network online
After each computers name you will see whether it is on-
line or not. When a computer is online, it will receive trans-
port and timecode signals, and its sequencer application 
can be started and stopped by remote control. If it is off-
line, it can only be started from its own keyboard – it is ef-
fectively an independent machine, although it is still on the 
network.
ÖNote that any computer can control any and all of the 
others – VST System Link is a peer-to-peer network and 
there is no absolute “master” computer.
However, most users do like to think of one machine as the master (in a 
one person/two computer network, this would be the machine you actu-
ally sit behind most of the time). 
For now, lets put all computers online:
1.Activate the Online checkbox in the VST System Link 
panel for all computers. 
2.Check that the system is working by pressing Play on 
one computer – all computers should start almost instantly 
and play perfectly in time, with sample-accurate precision.
The Receiving and 
Sending indicators 
						

							464
Synchronization
The Offset Samples setting allows you to adjust whether 
one machine will play back slightly ahead or behind the rest.
This is normally not needed, but occasionally with some hardware you 
may find that the lock is a few samples out. In that case you can adjust 
the lock with the Offset value. For now, leave it set to 0 – it will most likely 
be what you want.
The Transfer Bits setting allows you to specify whether 
you want to transfer 24 or 16 bits. This allows you to use 
older audio cards which do not support transfer of 24 bits.
VST System Link sends and understands all transport 
commands, so you can play, stop, fast forward, rewind 
etc. the entire network from one computer without a prob-
lem – try it! If you jump to a locator point on one machine, 
all other machines will also instantly jump to that locator 
point. You can even scrub on one computer and have the 
video and audio on another computer actually scrub right 
along with you.
Using MIDI
As well as supplying transport and sync control, VST Sys-
tem Link also supplies up to 16 MIDI ports, each with 16 
channels. You set this up as follows:
1.Use the MIDI Inputs and Outputs value boxes to spec-
ify the number of MIDI ports you need.
The default value is 0 MIDI In and 0 MIDI Out ports.
2.Create a MIDI track in the Project window and open 
the Inspector (top section).3.If you now pull down the Input or Output Routing pop-
up menus, you will find the specified System Link ports 
added to the list of MIDI Inputs and Outputs.
This allows you to route MIDI tracks to VST instruments 
running on another computer, as described in the applica-
tion examples (see “Using one computer for VST instru-
ments” on page 466).
The “Active ASIO Ports for Data only” setting
If you are sending huge amounts of MIDI data at once, 
there is a small possibility that you might run out of band-
width on your VST System Link network. This will manifest 
itself by notes “choking” or timing becoming erratic.
If this happens, you can devote more bandwidth to MIDI 
by activating “Active ASIO Ports for Data only” in the VST 
System Link Setup panel. When this is activated, the VST 
System Link information will be sent on the entire channel 
instead of just one bit, more than enough for all the MIDI 
you could ever hope to use. The downside is that you can 
no longer use this ASIO channel for audio transfer (do not 
connect it to a speaker!), thus leaving you only 7 channels 
of audio in our ADAT cable example. Depending on how 
you work this might be a reasonable compromise.
!Make sure that all computers have their tempos set 
to the same value, otherwise your synchronization 
will be seriously skewed. 
						

							465
Synchronization
Hearing the network audio
If you are using an external mixing desk, hearing your audio 
really isnt an issue – just plug the outputs of each computer 
into the desired channels on the external mixing desk, press 
Play on one of the computers, and youre good to go.
However, many people prefer to mix internally inside the 
computer and just use a desk for monitoring (or maybe not 
use any external mixer at all). In this case youll need to se-
lect one computer to be your “main mix computer” and 
send the audio from your other computers into this.
In the following example, we assume you are using two 
computers, with computer 1 as your main mix computer 
and computer 2 running two additional stereo audio 
tracks, an FX channel track with a reverb plug-in and a 
VST instrument plug-in with stereo outputs.
1.First you want to set things up so that you can listen to 
the audio playback from computer 1.
In other words, you need an unused set of outputs, e.g. an analog stereo 
output, connected to your monitoring equipment.
2.Go to computer 2 and route each of the two audio 
tracks to a separate output bus.
These should be busses connected to the digital outputs – let’s call 
them Bus 1 and 2.
3.Route the FX channel track to another VST System 
Link bus (Bus 3).
4.Route the VST instrument channel to yet another bus 
(Bus 4).
5.Go back to computer 1 and check the corresponding 
four VST System Link input busses.
If you start playback on computer 2, the audio should “appear” on the in-
put busses on computer 1. However, to mix these audio sources you 
need actual mixer channels:
6.Add four new stereo audio tracks on computer 1 and 
route these to the output bus you use for listening, e.g. to 
the analog stereo outputs.
7.For each of the audio tracks, select one of the four in-
put busses.
Now, each computer 2 bus is routed to a separate audio channel on 
computer 1.
8.Activate monitoring for the four tracks.If you now start playback, the audio from computer 2 will 
be sent “live” to the new tracks on computer 1, allowing 
you to hear them together with any tracks you play back 
on computer 1.
For more information about Monitoring, see “About moni-
toring” on page 17.
Adding more tracks
OK, but if you have more audio tracks than you have VST 
System Link busses (physical outputs)? Then you just use 
the computer 2 mixer as a submixer: Route several audio 
channels to the same output bus and adjust the output 
bus level if needed.
Note also that if your audio cards have multiple sets of in-
put and output connections you can link up e.g. multiple 
ADAT cables and send audio via any of the busses on any 
of the cables.
Internal mixing and latency
One problem with mixing inside the computer is the la-
tency issue we mentioned earlier. The VST engine always 
compensates for record latencies, but if you are monitor-
ing through computer 1 you will hear a processing delay 
while you listen to signals coming from your other comput-
ers (not on your recording!). If your audio card in computer 
1 supports ASIO Direct Monitoring you should definitely 
turn this on – youll find the setting in the VST Audio Sys-
tem Device Setup panel (see “ASIO Direct Monitoring” on 
page 72). Most modern ASIO cards support this function. 
If yours doesnt you may want to change the Offset value 
in the VST System Link Setup panel to compensate for 
any latency issues. 
						

							466
Synchronization
Setting up a larger network
This is not much more difficult than a two computer net-
work. The main thing to remember is that VST System Link 
is a daisy chain system. In other words, the output of com-
puter 1 goes to the input of computer 2, the output of 
computer 2 goes to the input of computer 3, and so on 
around the chain. The output of the last computer in the 
chain must always go back into the input of computer 1, to 
complete the ring.
Once youve done this, the transmission of all the trans-
port, sync, and MIDI information to the whole network is 
handled pretty much automatically. However, where you 
may run into confusion in a large network is in the trans-
mission of audio signals back to a central mix computer.
If you have lots of hardware inputs and outputs on your 
ASIO cards you dont need to send audio via the chain at 
all, but can transmit it directly to the master mix computer 
via one or more of its other hardware Inputs. For example, if 
you have a Nuendo Digiset interface or 9652 card on com-
puter 1 you could use ADAT cable 1 for networking, ADAT 
cable 2 as a direct audio input from computer 2, and ADAT 
cable 3 as a direct audio input from computer 3.
You can also transmit audio via the ring system if you dont 
have enough hardware I/Os for direct audio transmission. 
For example, in a four computer scenario you could send 
audio from computer 2 into a channel in the mixer in com-
puter 3, and from there to a channel in the mixer in com-
puter 4, and from there back to the master mixer in 
computer 1. This can certainly be tricky to set up, so gen-
erally it is recommended that if you want to set up a com-
plex network, you should make sure to use ASIO cards 
with at least three separate digital I/Os. 
Application examples
Using one computer for VST instruments
In this example, one computer will be used as main record 
and playback machine, and another computer as a virtual 
synth rack.
1.Record a MIDI track into computer 1.
2.Once you have finished recording, route the MIDI out-
put of that track to System Link MIDI port 1.
3.Now go to computer 2, open up the VST Instrument 
rack and assign an instrument to the first slot in the rack.
4.Route the VST Instrument channel to the desired out-
put bus.
If you are using computer 1 as your main mixing computer, this would be 
one of the VST System Link output busses, connected to computer 1.
5.Create a new MIDI track in the Project window of 
computer 2, and assign the MIDI output of the track to the 
VST Instrument you created. 
6.Assign the MIDI input of the track to be VST System 
Link port 1.
Now, the MIDI track on computer 1 is routed to the MIDI track on com-
puter 2, which in turn is routed to the VST Instrument.
7.Now activate monitoring for the MIDI track on com-
puter 2, so that it will listen and respond to any MIDI com-
mands coming in.
In Nuendo, you would click the monitor button in the Track list or Inspec-
tor.
8.Press play on computer 1.
It will now send the MIDI information on the track to the VST Instrument 
loaded on computer 2.
Even with a slow computer you should be able to stack a 
whole bunch of extra VST Instruments this way, expanding 
your sound palette considerably. Dont forget that VST 
System Link MIDI is also sample-accurate, and thus has 
much tighter timing than any hardware MIDI interface ever 
invented! 
						

							467
Synchronization
Creating a virtual effect rack
The effect sends for an audio channel in Nuendo can ei-
ther be routed to an FX channel track or to any activated 
Group or output bus. This allows you to use a separate 
computer as a “virtual effect rack”, by setting things up in 
the following way:
1.Go to computer 2 (the machine you will use as effect 
rack) and add a new stereo audio track.
You cannot use an FX channel track in this case, since the track must 
have an audio input.
2.Add the desired effect as an insert effect for the track.
Let’s say you add a high-quality reverb plug-in.
3.In the Inspector, select one of the VST System Link 
busses as input for the audio track.
You want to use a separate System Link bus, which will only be used for 
this purpose.
4.Route the channel to the desired output bus.
If you are using computer 1 as your main mixing computer, this would be 
one of the VST System Link output busses, connected to computer 1.
5.Activate monitoring for the track.
6.Now, go back to computer 1 and select a track to 
which you want to add some reverb.
7.Bring up the effect sends for the track, in the Inspector 
or the mixer.
8.Pull down the send routing pop-up menu for one of 
the sends, and select the VST System Link bus assigned 
to the reverb in step 3.
9.Use the send slider to adjust the amount of effect as 
usual.
The signal will be sent to the track on computer 2 and pro-
cessed through its insert effect, without using any proces-
sor power on computer 1.
You can repeat the steps above to add more effects to the 
“virtual effect rack”. The number of effects available this 
way is only limited by the number of ports used in the VST 
System Link connection (and of course by the perfor-
mance of computer 2, but given that it won’t have to han-
dle any recording or playback, you should be able to use 
quite a lot of effects).
Getting extra audio tracks
All computers on a VST System Link network are locked 
with sample-accuracy. Therefore, if you find that the hard 
drive on one computer isn’t fast enough to run as many 
audio tracks as you need, you can record new tracks on 
one of the other computers instead. This would create a 
“virtual RAID system”, with several disks all operating to-
gether. All tracks will remain locked together just as tightly 
as if they were all running on the same machine. This 
means that you effectively have an unlimited track count! 
Need another 100 tracks? Just add another computer.
Dedicated Video Playback
Playback of high-resolution video can be taxing on a sys-
tem’s CPU. By dedicating one computer for video play-
back via System Link, you can free up resources on your 
main CPU for audio and MIDI processing. Since all trans-
port commands will respond on the System Link comput-
ers, scrubbing video is possible even when it is coming 
from another computer. Spotting sound effects to picture 
in Edit Mode will work the same way as it does on one 
computer. This is a viable and economic alternative to 
dedicated hard disk video systems like the Doremi V1. 
						

							36
Video 
						

							469
Video
Background
Nuendo plays back video films in a number of formats. 
Under Windows, video playback can be done using the 
playback engines DirectShow, DirectX Video or Quick-
Time. 
Under Mac OS X, QuickTime is always used as playback 
engine.
There are several ways to play back video:
Without any special hardware.
While this will be fine in many situations it does put a limit on the size of 
the internal video window as well as the quality of the image.
Using FireWire (Mac OS X only).
Using a FireWire port, you can play back video on an external monitor us-
ing a DV-to-analog converter or a DV camera.
This is valid for DV video and QuickTime is used for playback. This can 
reduce the CPU load since the external device is decoding the DV video 
stream.
Using Graphics cards (Windows only).
Multi-head graphics cards which support overlay functionality can be 
used to display the video picture on an external monitor. As of this writ-
ing, the following manufacturers have working solutions available: nVIDIA 
and Matrox.
Using Video cards.
Video cards can also be used to display the video on an external monitor. 
Please note that this utilizes some of the CPU to process the video data. 
As of this writing, e. g. the “Decklink” card (Blackmagic) can be used.
Before you start
When working on a project involving a video file, there are 
several points to bear in mind:
The playback engine is used not only for playback of the 
video file, but also to provide file information in Nuendo. To 
make sure that you have chosen the right player for a par-
ticular type of video file, check the file information dis-
played in Nuendo (e. g. in the Import Video dialog or the 
Pool) prior to trying to import or playing back the file.When this information reads “0x0 pixel”, “0.000 s” and “0 
Frames”, the video file is either corrupt, or the format is not 
supported by the codecs available to the selected video 
playback engine. You will either have to change the video 
playback engine, or install the required codec. 
ÖAs a general rule, Nuendo should be able to use a cer-
tain video file, if the native video player on your system 
(Windows Media Player on the PC or QuickTime Player 
on the Mac) can play this file.
ÖYou can expect most Windows hardware to work with 
DirectShow and DirectX Video.
On a Windows system, the DirectShow and DirectX Video players are 
provided by the operating system, you don’t have to install any additional 
software. Make sure you are using the latest version of DirectX software 
available from the Microsoft web site.
ÖFor the QuickTime playback method to be available, 
you must have QuickTime 7.1 installed on your computer.
If you don’t have QuickTime, or if a version lower than 7.1 is installed, 
QuickTime playback will not be available in Nuendo. There is a freeware 
version (a QuickTime installer is included on the Nuendo DVD if required, 
or you can download it from www.quicktime.com) and a “pro” version, 
which offers additional video cutting options. The player engine is the 
same in both versions, so for mere playback in Nuendo there is no need 
to purchase the “pro” version.
!Trying to import or play back a file not supported by 
the selected video player will lead to unpredictable 
results – if no information on the number of frames, 
the length and the pixel resolution is available (e. g. in 
the Import Video dialog), you cannot import/play this 
file properly with this particular video player.
!Under Mac OS X, there is only one standard player 
option. The QuickTime playback engine is always 
used, supporting the formats AVI, MPEG, QuickTime 
and DV. If your system has a FireWire port, there is 
also a FireWire option – see “Playing back a video 
file via FireWire (Mac OS X only)” on page 473. 
						

							470
Video
Selecting the video playback engine 
(Windows only)
When using Nuendo on a Windows system, you can se-
lect the playback engine in the Device Setup dialog (Video 
Player page).
Which playback engine to select depends largely on 
which type of video system you are using, as well as on 
the file format and codec of the video files you want to 
work with.
When you have changed the video playback engine, 
make sure to remove any previously imported video file 
from the Pool, and re-import it.
A note on editing
Nuendo allows you to cut, copy, paste and trim video 
events, i. e. your video track may contain more than one 
video event. Make sure that these video files are of the 
same file format and resolution in order for them to play 
properly. 
ÖWindows only: When using the DirectShow video 
playback engine, you may find that only the first event on 
the video track is played back correctly. In such a case 
make sure that the video track contains no more than one 
video event. When you need to edit your video files (i.e. 
cut, copy, paste or trim video events), it is therefore rec-
ommended to use the DirectX Video player.
ÖWindows only: If you find that you are unable to edit a 
video file copied from a CD, this might be due to the fact 
that files copied from CD are write-protected by default. 
Right-click the file, and deactivate the “Read-Only” option 
in the File Properties dialog.
When you have a video file in a format not supported by 
Nuendo, use an external application to convert it to a for-
mat that Nuendo can import.
Operations
Importing a video file
Video files are imported in the same manner as audio files.
By using the File menu (Import Video File).
By using drag and drop from the Windows Explorer, the 
Mac OS Finder, the Pool or the Media Bay.
By importing to the Pool first and then dragging to the 
Project window (see the chapter “The Pool” on page 296 
for details).
Note:
 To be able to play back the video, you must add a video track 
(by using the Add Track submenu on the Project menu or Quick 
menu). You can only have one video track in each project.
 You can have multiple video files on the track but all files must 
be of the same size and compression format.
 You may trim video files in the project window as needed, ad-
justing the event boundaries as you would for an audio event.
 The Import dialog has an option for extracting the audio from a 
video file (see “Extracting audio from a video file” on page 472) 
and for generating a thumbnail cache file for the video file, see 
below.
Video import preferences
In the Preferences dialog (Editing–Video page), there are 
two options that affect the import of video files:
Extract Audio on Import Video File
When this is activated, the audio will automatically be extracted and im-
ported into the project when you import a video file. This way, the audio 
will also be included when you insert a video e.g. by using drag and drop. 
When you import video files by using the File menu, you can activate this 
option separately for each imported video file on the Import dialog.
Generate Thumbnail Cache on Import Video File
When this is activated, a thumbnail cache file will be created automati-
cally when you import a video file. This is handy, as a cache file will also 
be created when you import a video file using drag and drop. When you 
import video files by using the File menu, you can activate this option 
separately for each imported video file on the Import dialog, see below.