Knowledge Base

MediaRecorder 6.5 - Technical Specifications

MediaRecorder is Noldus' recording tool for FaceReader and The Observer XT. It allows you to record from USB and IP cameras as well as screen capture devices.

Video Formats

Video recordings contain a lot of idle information, making uncompressed video streams extremely inefficient and difficult to handle. Therefore, MediaRecorder uses the modern common video compression standards of MPEG 4 H.264.

MPEG-4, H.264 - IP Camera

• Video encoding: MPEG-4 Part 10
• Audio encoding: AAC Audio
• Container: MP4
• Approximate file size: At least 0.5 GB/hr

These files can be used in The Observer XT 15 and higher and FaceReader 8 and higher.

Please note that H.264 is a video compression format. Although often used in combination with High Definition resolution videos, it is not a synonym for HD.

How to Choose Your Camera

Which camera is best suited for your project may depend on a lot of factors. Noldus has tested several different camera types. As there is a wide variety of cameras available on the market today, not all possible cameras could be tested. The cameras tested are indicated by their connection type: USB and IP.

Recommended Cameras for Recording Media Files

To record media files from video inputs for later use in The Observer XT or FaceReader, suitable cameras include:

• 1-2 Logitech Brio webcams
• 1-4 IP cameras (Axis P5525, Axis M1065), or successors

Recommended Devices for Screen Capture

To make a screen capture and record an image of the test subject, suitable combinations of devices include:

• Axis P5525 / M1065 IP camera + Epiphan Nano Broadcaster
• Logitech Brio Webcam + DVI2USB 3.0

Combining Cameras and Devices

Noldus does not recommend recording from mixed source types. However, there are a few exceptions and special set-ups listed below. Other combinations are not recommended, at least not without extensive testing on synchronicity.

Stationary Usability Lab

The Stationary Usability Lab contains an Epiphan Nano Broadcaster for screen capture and 1 or more Axis P5525 IP cameras connected to a Dell Precision 3660 desktop.

• Manufacturers: Epiphan Nano Broadcaster, Axis P5525 IP camera
• Resolution / frame rate per second:
  • DVI: 1920x1080 / 30 fps
  • Axis: 1980x1080 / 30 fps
• Number of devices: 4 (i.e. 1 screen capture + 3 cameras)
• Max. recording duration: 3 hours
• Remarks: Separate microphone over line-in or over RTSP

Portable Usability Lab

The Portable Usability Lab is a set-up of an Epiphan DVI2USB 3.0, a screen capture device, and 1 Logitech Brio USB camera connected to a Dell Precision 3570 laptop.

• Manufacturers: Epiphan DVI2USB 3.0, Logitech Brio Webcam
• Resolution / frame rate per second:
  • 1920x1080 / 30 fps
  • 1920x1080 / 30 fps
• Number of devices: 2-4
• Max. recording duration: 1 hour
• Remarks: Microphone via USB webcam or separate microphone over line-in or over RTSP

Portable Observation Lab

The Portable Observation Lab is a set-up of two Logitech Brio webcams connected to a Dell Precision 3570 laptop.

• Manufacturer: Logitech Brio Webcam
• Resolution / frame rate per second: 1920x1080 / 30 fps
• Number of devices: 2-4
• Max. recording duration: 1 hour
• Remarks: Microphone via USB webcam or separate microphone over line-in or over RTSP

Using the Right Computer

MediaRecorder is thoroughly tested on a Dell Precision 3660 workstation and a Dell Precision 3570 laptop. The number of cameras that can be used simultaneously depends on the processor speed of your computer, the Graphical Processor Unit (GPU, also called video card), the type of camera used, and the camera settings. Programs running in the background also influence the speed of your computer and may affect the number of cameras that can be used simultaneously in sync. For example, virus scanners are well known for delaying computer performance and thus causing a recording to be out of sync with another recording or with the audio.

It is possible to buy a consumer-range computer with a high processor speed and more than 4 GB of memory, but in order to remain competitive regarding price, manufacturers often economize on the underlying system architecture. That means those computers are suitable for home use, but not for running professional scientific software. It is advisable to select a computer intended for professional use or labelled by the manufacturer as a workstation. If you use an older workstation, it should have a 2.6 GHz processor speed and at least 4 GB of memory (8 GB is recommended) as well as a separate video card supporting Direct3D acceleration.

MediaRecorder is tested on Windows 11, 64 bit.

MediaRecorder with The Observer XT

External Commands

In The Observer XT, you can control MediaRecorder by using the program Noldus N-Linx command. Setup is very easy and the exact procedure and commands can be found in the MediaRecorder manual.

Automatic Linking

Using N-Linx to communicate between The Observer XT and MediaRecorder, the recorded videos are automatically transferred to The Observer XT.

Download the original PDF: Media Recorder 6.5 - Technical Specifications (PDF)