Content overview

Questions on hardware and drivers 

• Supported video hardware 
• Recommended video hardware 
• Recording video with portable computers 
• USB Camera support 
• DV Device support

General questions 

• Video recording format 
• No user interaction possible with LECTURNITY Assistant after starting a video recording 
• Random Visible Scrolling in Player very slow 
• Very large video files (high datarate)

Questions on codecs

• General information on codecs 
• Compatibility of codecs and LECTURNITY
• Listing of installed codecs
• Recommended codecs
• Unrecommendable codecs
• Preinstalled Indeo Video 5
• Indeo Video 5 not selectable in Assistant
• iv50 not selectable despite being installed
• Compatibility of DivX and LECTURNITY
• Changing the codec after recording

Questions on DV (Digital Video) 

• General Assistant settings for DV
• Problem handling when recording with a DV camera
• General information on DV recording
• Type-1 and Type-2 DV Video

Question: Which video hardware is supported?

Any Windows Driver Model (WDM) compatible video source is supported.

Question: Which video hardware is recommended?

For professional results in video recording, the following hardware is recommended:

• Video capture card for the PCI bus, such as the Osprey-100 by ViewCast,
• Analog video cameras, connected to the capture card by S-VHS.

As an alternative, the following combination has been tested successfully as well:

• Digital video camera (DV),
• Performant computer (800 MHz upwards) with FireWire interface (also known as i-Link).

Question: How can I record videos with my notebook computer?

Solution: Various possibilities exist how a video can be recorded by means of a notebook computer and LECTURNITY:

• By using a USB Camera,
• By using a DV Camera and a FireWire interface,
• By using an external capture device, such as the Osprey-50 by ViewCast in combination with an analog video camera.

Please also read our Hardware recommendations.

The use of a DV camera or an external capture device with an analog video camera achieves the best results. For high-quality applications we do not recommend the use of USB cameras.

Question: Are USB cameras supported as well?

USB cameras are supported for the video recording by LECTURNITY, as long as they are compatible with the WDM (Windows Driver Model). This is the case for most cameras, also for the USB cameras by TerraTec.

With regard to USB cameras, it has to be taken into consideration that in the case of some camera models the data transfer from the USB bus to the LECTURNITY Assistant might need a very high processing performance so that optimal results cannot be achieved. The reason also lies in the confined transfer rate for the USB bus which is about 12 mbps (somewhat more than 1 MB per second).

This data is relevant for USB cameras according to the USB 1.1 specification. It might change for USB 2.0 cameras.

Question: Are DV devices supported as well?

Yes, DV devices are explicitly supported. LECTURNITY offers certain functions in order to code DV data directly with (almost) any codec.

See the section on DV configuration.

Question: In which format does LECTURNITY record videos?

LECTURNITY records videos in the standard video format "AVI" (Audio Video Interleaved).

Question: After starting a presentation recording including a video, the LECTURNITY Assistant does not react on user demands; in some cases only a restart of the computer helps. What have I done wrong?

For testing purposes, please produce a video recording with another capture program (e. g. AMCap). Please take care that the same settings are made as in LECTURNITY:

1. The recording works in the other program without problems. In this case, please contact the LECTURNITY Customer Service Center.
2. The same problems occur as with the recording by means of LECTURNITY.

If the same problem also occurs in the other program, then the following causes are possible:

• Image resolution too high: If the video image has a too high resolution, then the computer might not be able to compress the video in real-time. The problems described above are the consequence.
• Solution: Reduce the resolution with which the video is recorded.
• Inappropriate codec: Some video codecs (see also Questions on codecs) are not appropriate for the real-time compression of videos, or they are not set correctly.

Solution: Try to adapt the settings of the codec or to set a different video codec.

Question: In presentations it might happen that the "Random Visible Scrolling", i. e. the visual navigation in a LECTURNITY Presentation, becomes very slow. This might especially occur when a video is part of the presentation. What can I do about this?

There are various reasons for bad performance in combination with video:

• The computer is not powerful enough: The computer is not performant enough for the replay of a video parallel to the replay of the remaining presentation data.
• Keyframe distance too high: When the distance between keyframes during the recording is set on a too high level, then the visual navigation in a video becomes very low since the active image has to be generated from the keyframe and from each following frame to the current point of time. If the distance is of some 250 frames, then it might happen that up to 249 frames have to be calculated in order to generate one image of the video. A guideline for the distance between keyframes should be one keyframe per second or minimally every other second, i. e. at 25 fps, a maximum of 50.

Question: The video recorded with LECTURNITY is very large (considering its data size). How can I produce smaller videos?

The used codec is not appropriate and produces large amounts of data. Possibly, the recording was performed with an inappropriate codec setting. Alternatively the resolution of your recording is too large and thus produces large videos.

Solution: Use an appropriate codec already for recording, such as "Indeo Video 5" or "DivX". If you have already created a recording with a wrong codec resp. faulty setting, you may transcode the video by using the LECTURNITY Editor. Alternatively, you can use the third-party application VirtualDub. See also the section Changing the codec after recording.

Question: What is a codec?

A codec (encocoder-decoder) is a piece of software used for compressing raw video data during recording and for decompressing them during replay. A video recording is always made in the AVI format, but the video data in this avi file are compressed by a codec.

A video compressed or recorded by a certain codec can only be replayed on computers on which this precise codec is installed. It is thus possible that a computer can replay some videos in the AVI format, but others not. You cannot tell right away with which codec an AVI file was compressed.

A video file may also be uncompressed; then the raw video data are saved in an AVI file. Such videos have a very high data volume (many MB per second).

Question: Which codecs work with LECTURNITY?

LECTURNITY can record videos with any codec compatible with Windows Driver Model (WDM) and installed on Windows (cf. DirectShow codecs, which cannot be used in LECTURNITY).   Please keep in mind that the same codec has to be installed for replay (see above). Furthermore, it has to be noted that not all codecs are compatible with all entry formats (see below).

Question: How do I find out which codecs are installed on my system?

Solution: Under Windows, you have to open the system control ("Start", "Settings", "System control"). The codecs are found under:

• Windows 2000: "Sounds and Multimedia", "Hardware", "Video codecs", "Properties", "Properties"
• Windows XP: "Sounds and Multimedia", "Hardware", "Video codecs", "Properties", "Properties"

Question: Which codecs are recommended?

For video recording by LECTURNITY, we recommend the iv50 codec (Indeo Video v5.10 or v5.11). This codec has a good compression rate (i.e. a good relation of quality to data size), it is stable, freely available and, above all, preinstalled on most computers. This is the case for Windows 2000 and XP. On Windows XP SP1, however, the codec might have to be postinstalled. Please see Preinstalled Indeo Video 5 for further information.

 
For the use of the IV50 codec the setting of the "Quick Compress" mode is very important. Without it, a real-time compression is usually impossible. In order to set this mode, proceed as follows: look for the "Codec" in the Project Options, then click on the "Configure" button:

Figure 1: Codec options in the LECTURNITY Assistant

In continuation, make sure that in the codec setting dialog the checkbox "Quick Compress" is activated:

Figure 2: Configuration dialog of iv50 codec

Question: Which codecs are not recommended?

Among others, the following codecs are not recommendable, since they are not performant enough for the real-time compression of videos:

• cpak: Cinepak Codec by Radius Inc.
• mscv: Microsoft Video 1
• mrle: Microsoft RLE Video

This listing contains codecs which are installed on every Windows system, but which are exclusively provided due to compatibility reasons.

Question: On which systems is iv50 preinstalled?

On the following operating systems the codec iv50 (Indeo Video 5) is preinstalled: 

• Windows 2000,
• and Windows XP (non-SP1).

On the following operating systems Indeo Video 5 is not preinstalled and might have to be installed manually:

• Windows XP SP1

Solution: In order to install iv50 on your system, please continue as follows:
Windows XP SP1: If your system has been equipped directly with Windows XP SP1, i.e. SP1 has not been installed subsequently, then Indeo Video 5 is not installed. The codec, however, can be postinstalled by installing the Hotfix #327979 e.g. by using the Windows XP update functionality.

Question: In the LECTURNITY Assistant the codec iv50 (Indeo Video 5) cannot be selected. If you call the Online Help with the LECTURNITY Player, an error message appears that a required video codec has not been found. Why can't the codec been found?

The video codec iv50 is possibly not installed. Solution: Please check whether the iv50 codec is installed. To do so, proceed as described here. If the codec "Indeo Video 5" does not appear on the list, you may download it here and install it afterwards. 

Question: I cannot select the iv50 codec (or codec xyz) although it is definitely installed. Why?

Solution: The codec "Indeo Video 5" (iv50) can only work with RGB data as entry data, and not with any other coded streams such as YUV- or I420-coded video streams. Most video devices can deliver various formats; in the index "Video" of the Project settings in the LECTURNITY Assistant, click on the "Format" button and select an RGB format in the device dialog (24- or 15/16-Bit RGB). The selection of the video format depends on the device and is not part of LECTURNITY.

Figure 3: "Format" button for setting the Color model and Frame Rate

This is exactly how it happens that other codecs have problems with different entry formats. E. g. the well-known codec "DivX" can code RGB data in a 24-bit format as well as data in the i420 format, but not RGB data in the 16-bit format.

Question: Can I record videos with LECTURNITY and the DivX codec? 

Yes, videos can be recorded by LECTURNITY using the DivX codec, provided your computer is performant enough and the codec is correctly configured (fast compression). Please note the problem that the computers on which the video/the LECTURNITY Presentation will be replayed, must have the codec installed which was used for the video recording. At a video size of 320x240 pixels a setting of DivX to about 250-400 kbps and "1-pass Slowest Compression" provides good results, especially in case of relatively static scenarios (e. g. a lecturer in front of a still background).   Please note that the 5.0.3 version of DivX causes considerable problems. If you have this DivX version installed on your system, you should definitely install a version higher than or equal to 5.0.4.   Also note that DivX Networks claims to be downwards compatible with older versions of the DivX codec. This only applies in one direction: videos which were created with older versions of DivX are replayed correctly with newer DivX versions, but not always vice versa. Problems caused by this conflict may include blank videos and/or system crashes on systems using an older DivX version than the one which was used for recording.

Question: The video recording was made with a codec which is not installed on the target computers. This problem may also occur when a hardware codec (e. g. MJPG in some more expensive capture cards) is used for recording. How can I change the codec afterwards?

Solution: The video recording can be transcoded after recording by using the LECTURNITY Editor. Load the recording document into the Editor, select the wanted codec in the "Export and Preview Settings" and then export your project into a new recording document.
 
Please note that this may be a rather lengthy operation.
It is also possible to transcode the video by using the program VirtualDub, which is freely available. In addition, the orginal file has to be renamed; subsequently the transcoded variant is used for the presentation instead of the original.

Please note that the version 1.5.2 of VirtualDub is not appropriate for codec conversion!

Question: How should I set up the LECTURNITY Assistant in order to record a DV (Digital Video)?
     

Solution: Please follow these steps in order to record a DV with LECTURNITY:

1. Please make sure the DV camera is turned on (and installed on the system) before you start the LECTURNITY Assistant; otherwise the device cannot be recognized by the LECTURNITY Assistant,
2. Then activate the video recording by clicking on the checkbox "Record video",
3. By clicking on the button "Settings" you can change the settings of the DV device. Here, especially the "DV-RGB-Converter" is interesting: with this function, the DV data can be converted directly into an uncompressed (RGB) video format so that (almost) any codec can be used for compression. You can select four different video sizes (see Fig. 2).

Figure 4: Settings of the DV decoder

Turn on the recording on the DV camera before you start the LECTURNITY recording. Otherwise it might happen that the DV camera turns off during the LECTURNITY recording (power saving).

If you encounter problems while using a DV camera with LECTURNITY you might consider the following things:

• DirectX version: We recommend using a DirectX version of 9.0c or higher in order to use DV recording with LECTURNITY. Older versions especially version 8.0 can lead to problems as some cameras are not detected automatically and thus cannot be used by Windows and LECTURNITY.
• Driver: A DV camera does not need any additional drivers with Windows 2000 or Windows XP in order to work with LECTURNITY. If you already have installed drivers and are encountering problems we recommend that you de-install these drivers.
• Fixed audio-video offset: We had reports that a correct audio-video offset cannot be determined with the camera model Sony Digital Handycam DCR-VX 1000E.

You can download the newest DirectX from Microsoft here: DirectX at Microsoft.

Question: What should I generally keep in mind when recording DV video with LECTURNITY?
     

During the recording of video data by means of a DV camera very high data volumes are temporarily created. The transfer rate of DV is 3,6 MB/s (approximately 29 mpbs). If you use a different codec than the integrated DV codec, then the DV data have to be converted into a more common color space first before they can be recompressed. This is a very time-consuming arithmetic operation.

Therefore, as a minimum, your system has to fulfil the following system requirements:

• Large CPU capacity, e. g. Pentium 4 of 1.4 GHz or equivalent (AMD XP1600+),
• Fast hard disk
• During recording, no applications should be active in the background.
  
  

Only this way can a fluent and undisturbed video recording be guaranteed.

Question: What is the difference between a Type-1 DV AVI file and a Type-2 DV AVI file?

When storing DV video into an AVI file, there are two different possibilities of doing so: either you store all DV data into a single stream in the AVI file (Type-1, media type ivas), or you split the DV data into video and audio data (Type-2, media types auds and vids). Splitting audio and video is necessary for a large range of programs, including LECTURNITY.

By using the external utility DV Converter from ULead, you may convert Type-1 AVI files to Type-2 AVI files. The resulting video files can be imported into the LECTURNITY Editor without any restrictions.
 
If you want to use DV AVI files as video clips, please continue reading here.
 
The Customer Service Center further contains a how-to on how to import a DV video into a LECTURNITY presentation.