Knowledge Base

MediaRecorder with FaceReader

Offline video analysis in FaceReader means analyzing prerecorded videos. The videos created by MediaRecorder can be used for offline video analysis in FaceReader 4 or higher. No special settings are needed to use files from MediaRecorder in FaceReader. However, if you record videos to use with the Remote Photo Plethysmography (RPPG) module in FaceReader we advise to use FaceReader-RPPG as the Output Quality setting. With this setting the videos will only be slightly compressed. The file size of the resulting videos is huge, about 260 Mb/minute. For more information see Output settings.

You cannot simultaneously analyze live video signals in FaceReader and create video files in MediaRecorder. If you want to analyze and record videos simultaneously, record the videos in FaceReader.

Prevent Black Frames at the Start of Your Videos

To make sure that MediaRecorder waits for an I-frame before it starts recording, you can edit the VsSettings file that comes with MediaRecorder. If you do not edit this file, your videos may start with black frames and FaceReader will not be able to analyze them from the start.

The VsSettings file is installed together with MediaRecorder. You can find the file in C:\ProgramData\Noldus\MediaRecorder\6.

By default the ProgramData folder is a hidden folder. In Windows Explorer on the View tab select Hidden items in the Show/hide section to view the folder.

1. Right-click VsSettings.xml and select Copy. Right-click and select Paste to make a copy of the file. Keep this copy in case you want to go back to the original settings.
2. Open the VsSettings.xml file in Notepad or a similar text editor.
3. From the Edit menu select Find and type Wait in the search field.
4. To make sure that MediaRecorder waits for an I-frame before it starts recording, edit the file and change 0 into 1.
5. Save the file.

Troubleshooting

If you are having problems, please first read Specifications or Requirements of a custom computer, to check whether your system is compatible with MediaRecorder. Also check the items below to see if there is a known solution for your problem.

No Video Preview

If one of your video inputs is black with a warning triangle and the message No signal from Video [n] is shown, the video source was not turned on when MediaRecorder was started. Press the Refresh button in MediaRecorder to show the image from that camera. You also get a black screen with a warning triangle when you have not yet selected this camera in the Video settings window.

See also Save the camera settings in Record video.

You will also have a black video input if your computer does not have an Nvidia graphics card. By default, MediaRecorder records two cameras on CPU and two on the video card (GPU) if you record from four cameras simultaneously. Only Nvidia GPUs facilitate the use of the GPU as additional processing power for compression of MediaRecorder videos. Other graphics cards are not able to do that. If you ordered a computer with MediaRecorder from Noldus Information Technology, it has an Nvidia card. By default, MediaRecorder checks whether this card is available and if so, uses it.

If you purchased a PC elsewhere, it may have a different graphics card and with the default settings, your cameras may give black inputs in MediaRecorder. To prevent this, you can edit the VsSettings file that comes with MediaRecorder.

To check the graphics card of your computer, click the Windows button and type Device Manager. In the Device Manager window expand the Display adaptors section. The computer's graphics cards are listed here.

The VsSettings file is installed together with MediaRecorder. You can find the file in C:\ProgramData\Noldus\MediaRecorder\6.

By default the ProgramData folder is a hidden folder. In Windows Explorer on the View tab select Hidden items in the Show/hide section to view the folder.

1. Right-click VsSettings.xml and select Copy. Right-click and select Paste to make a copy of the file. Keep this copy in case you want to go back to the original settings.
2. Open the VsSettings.xml file in Notepad or a similar text editor.
3. From the Edit menu select Find and type GPU in the search field.
4. To make sure that MediaRecorder does not use the GPU, edit the file and change -1 into 0. You can also change the value into 1 if your computer has one (Nvidia) graphics card. With this value MediaRecorder will not check what graphics card is available, it will use the card that is installed.

Installation Problems

If you get an error message during installation of the Picolo card, it is most likely that the card is not correctly inserted into your computer. Turn the computer off and disconnect the power cable. Press the card gently but firmly into place.

Sound Problems

If you are playing back multiple videos in The Observer XT and you hear an echo on the sound track, turn the sound off on all but one of the video monitors.

If you hear no sound on your recording this could be because:

• The speakers of your computer are not plugged in, they are turned off or their volume is low.
• The Windows volume control is muted or turned low.
• You have selected Line-in for your audio device instead of Microphone.
• You do not have an audio source connected.

Insufficient Disc Space

If your output folder is on the C: drive it is possible that you will have insufficient file space. Most computers are configured with more file space on the D: drive, so select your output folder on the D: drive.

Missing Frames When Controlling Recording with External Programs

When you send commands to MediaRecorder from external programs like EthoVision XT or The Observer XT, there is a small delay in starting the actual recording with MediaRecorder. This results in some missing frames at the start of the video file. Allow enough time at the start of recording to compensate for this delay.

When the command Start Recording is given before MediaRecorder is open and has loaded the cameras, recording does not start.

To measure this delay, make for example a video of a digital clock and compare the time the command Start Recording is given with the time at the first frame of the video.

Problems Loading MediaRecorder

MediaRecorder opens using the configuration file Current settings.mrs. When problems occur with these settings, open MediaRecorder with the default settings and recreate camera settings. To do so:

1. Delete the file Current settings.mrs from the following folder: C:\Users\Public\Documents\Noldus\MediaRecorder
2. Re-open MediaRecorder.
3. Re-select the cameras. A new file Current Settings.mrs is created.

See also Save the camera settings in Record video.

Tools for Troubleshooting

VideoInspector

This free tool gives basic information about the video files you are trying to play (such as which codecs they were made with) and reports which codecs are installed on your computer. It is reasonably easy to use. It does not report details such as the I-frame rate.

http://www.kcsoftwares.com/?vtb

GSpot

Although GSpot has not been maintained since 2007, it is a powerful tool to get information about both your video file and your computer system. GSpot is a free tool. It is less easy to use than VideoInspector.

In addition to providing detailed information about the video file you have opened, GSpot can be used to adjust how Windows uses the codecs installed. This is an advanced function and you should only use it if you understand what you are doing, and carefully write down the changes you make. If several codecs are installed which can be used to play one format, Windows assigns a merit to each codec to determine its preference. You can use GSpot to change the merit of each codec and in that way select which one is used by Windows (and so by other software). This is a way in which you can solve problems of codecs conflicting with each other, for example a piece of software such as The Observer XT works best with a particular codec, but another installation has set the merit of an alternative codec higher.

http://gspot.headbands.com

MediaInfo

MediaInfo provides detailed information about media files. It has less information than GSpot, but at the publication date of this manual, it was maintained.

http://www.mediainfo.sourceforge.net/en

Windows System Information

This can be obtained in Windows with System and Security / System / Advanced System Settings, Dxdiag.exe, and the Device Manager (in the Control Panel).

For full system information, SIW is a useful tool.

http://www.gtopala.com

Support

Help Menu

MediaRecorder's Help menu contains the following options:

• Help topics - Opens the MediaRecorder Help. You can search and find help topics.
• Noldus Online - If your computer is connected to the Internet, you can choose this option to go to the MediaRecorder home page on the Noldus website or to the MyNoldus portal. On the MyNoldus portal you can download the latest version of the software and documentation, submit support cases and view your account information. If you encounter a problem with MediaRecorder, you can inform Noldus IT with the Report an Issue option.
• Upgrade - If you have purchased an upgrade of MediaRecorder, choose this option to type the new Upgrade Key number that you have received from Noldus.
• About MediaRecorder - Choose this option to see details of exactly which version of MediaRecorder you are using. Click User Info to see the registered user and license number of your software.

Technical Support

For questions about MediaRecorder or any other Noldus product, contact the Support department by opening the Help menu in MediaRecorder, select Noldus Online and subsequently Get Support. The help desk may ask for the MediaRecorder log file. You can find this file in the folder C:\Users\<login name>\AppData\Local\Temp.

Record at a Predefined Time

Use this procedure to schedule video recording. This is especially useful when you want to start recording in the middle of the night, or you do not want to disturb the test subjects by handling the video software.

IMPORTANT: The procedure below is an example of the possibilities of Windows Task Scheduler, which is a default program in Windows 10. Since Windows Task Scheduler is a Microsoft program, Noldus IT offers no support for this feature.

Procedure

1. Type Task Scheduler in the Apps window.
2. Choose Action > Create Task.
3. In the General tab, type a name in the Name field, for example MediaRecorder with Webcam.
4. Optionally enter other settings in this tab and open the Triggers tab.
5. Click the button New.
6. Select On a schedule from the list next to Begin the task.
7. Enter the start time of the command in the Start field and choose whether you want to send the command once, daily, weekly or monthly.
8. Optionally enter Advanced Settings and click OK.
9. Click the Actions tab and choose New.
10. Choose Start a program next to Action.
11. Browse to MRCmd.exe.
12. Enter the command in the Add arguments (optional) field. For example, to start MediaRecorder and load the configuration file for your webcam, type: /E /C=Configuration_webcam.mrs. If the configuration file is not located in the folder C:\Users\Public\Public documents\Noldus\MediaRecorder, you must type the full path. If the file name or path contains spaces, you must use quotation marks at both ends.
13. Optionally select or change any settings on the other tabs.
14. Similarly, you can create tasks to start and stop recording at a predefined time with the commands /R and /S and to close MediaRecorder with the command /X. Create a task for each command.

IMPORTANT: Allow enough time between the commands. If a command is sent before the previous one is carried out, the second command is not carried out. For example, if the command Start Recording is sent before MediaRecorder is completely open, recording does not start.

By default, the tasks are stored in the folder Task Scheduler Library. To edit or delete a task, click this folder in the tree on the left side and select the task in the window Task Scheduler Library. In the Actions pane, click Properties, or Delete.

Integration with The Observer XT

Set Up Analog Cameras

Choose the situation that applies to you:

• You ordered computer, cameras, and MediaRecorder at Noldus IT: The video capture card is already installed in the computer. MediaRecorder has also been set up to use with these cameras. You can connect your cameras and start recording. See Record video.
• You bought the computer and cameras somewhere else: Follow the procedure below.

Install the Picolo Alert PCIe Card

Use this procedure to install the card that digitizes the output of analog cameras.

Prerequisites:

• You use MediaRecorder with analog cameras.
• You did not buy a complete setup from Noldus IT. If you bought a complete setup from Noldus IT, the card has been installed in the computer and you can skip this topic.

1. Make sure your computer is turned off and the power cable is disconnected.
2. Open the computer.
3. Select a free PCIe expansion slot, and remove the corresponding extension cover. See PCIe slot properties for more information on different PCIe slots in a Dell computer.
4. Unpack the Euresys Picolo Alert PCIe card, place it into the slot, and press it carefully into position. If the card does not fit into place easily, remove it and repeat the operation. IMPORTANT: When touching the board, its electronic components can be damaged by static electricity. To avoid any such risk, make sure that you are grounded. You can ground yourself by putting on an earthing wristlet, and attaching its clip to the metal frame of the computer. If an earthing wristlet is not available, you can hold the metal frame with one hand while holding the card in your other hand. Ensure also that your clothing does not touch any components while handling the card.
5. Fix the card to the chassis and re-fit the computer's cover.
6. Close the computer.

PCIe Slot Properties

Different PCIe slots have different properties, resulting in different performances. When possible, choose the slot that gives maximum performance. Take note of the slot version to estimate performance. Do not use the graphic slots.

PCIe slot performance per lane (values should not be multiplied by the number of lanes in a slot, for example x4, since the card has a 1x connector):

• PCIe v1.x: 250 MB/s
• PCIe v2.x: 500 MB/s
• PCIe v3.0: approximately 1 GB/s
• PCIe v4.0: approximately 2 GB/s

Install the Drivers for the Picolo Alert Card

Use this procedure to install the software that allows communication between the Euresys card and the computer operating system.

Prerequisites:

• You use MediaRecorder with analog cameras.
• You did not buy a complete setup from Noldus IT.
• You installed the Euresys Picolo Alert card into the computer.

1. Insert the MediaRecorder installation USB stick into your computer.
2. If you have the Picolo Alert card, open the folder Drivers and Tools\Drivers\Euresys\Alert and double-click the file multicam-win10-6.15.1.3573.exe.
3. Follow the instructions on your screen.
4. When installation is finished, a message appears that the drivers were successfully installed. Click Close.

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Source: Media Recorder 6.5 Reference Manual