A comprehensive guide to Analyzer’s Video Add In for simultaneous EEG and video playback
by Dr.-Ing. Kidist Mideksa
(Brain Products Scientific Consultant & User Application Test Manager)
Acquiring video with EEG provides insights into the interplay between neurophysiological responses and behavior, commonly used in infant and child research, sleep research, epilepsy research, and mobile EEG applications.
The Video Add In for BrainVision Analyzer 2 facilitates seamless parallel navigation of synchronously acquired video-EEG data.
This article provides a comprehensive overview of the Video Add In to help you get started easily.
Overview
- How can I install the Video Add In?
- How do I check if my dongle contains the video add-on license?
- What are the supported video file formats?
- Do I need separate codecs to play back the different video files?
- How do I import the video files into Analyzer 2?
- How to simultaneously navigate the EEG and video data
How can I install the Video Add In?
The video module is part of the Analyzer 2 software and is automatically included when installing Analyzer. It can be accessed under the Add Ins tab (see Figure 1). It is important to note that this module requires a dedicated license. Consequently, the module will only be visible and accessible if the corresponding add-on license has been purchased.
Figure 1: Accessing the Video Add In.
How do I check if my dongle contains the video add-on license?
Navigate to the Help tab and select About Analyzer. A new window will appear, displaying various details about your current Analyzer version and licensing information. If you have purchased the video add-on license, you will be able to see Analyzer 2 Video under the Add-on Licenses section (see Figure 2).
Figure 2: About BrainVision Analyzer – add-on license information.
The integration of the video license varies based on the specific dongle technology.
- 1
For the latest Sentinel technology: the purchased add-on license is already integrated and does not require further activation.
- 2
For the legacy HASP HL technology: the purchased add-on license needs to be installed and activated on every machine where Analyzer 2 is installed and where the Video Add In is needed. The steps for installing a license activation file are provided here.
From version 2.2.1, legacy HASP HL dongles are no longer supported. See here for more information on the steps required to upgrade your dongle in case you have not done so far.
You can easily identify your dongle’s technology by following the steps in our quick start documentation for single-user and network license dongles.
What are the supported video file formats?
The Video Add In supports two video file formats, namely:
- 1
.asf video files generated using the network camera solution. This format is officially supported from Analyzer version 2.3.0 onwards. In earlier versions, if the PC does not have the required codecs (see the codecs section below), it was necessary to install it from the Recorder video package.
- 2
.VisionVideo files generated using the legacy integrated/USB/Firewire camera solution. This format continues to be supported in the latest Analyzer versions to ensure backward compatibility.
Update to the latest version of Analyzer 2 to benefit from the enhanced Video Add In.
Do I need separate codecs to play back the different video files?
Depending on the type of the video files you are working with, dedicated video component installations are required.
- 1
.asf video files require manual installation of the Axis Media Control SDK, AxisAAC decoder, and AxisH264 decoder. The installers can be found on our website or in the Brain Products Application Suite USB (Components\Video_Components\Axis_asf).
- 2
.VisionVideo files require manual installation of the Lead codec. The installer can be found on our website or in the Brain Products Application Suite USB (Components\Video_Components\Legacy_VisionVideo).
How do I import the video files into Analyzer 2?
- 1
Store the video files and the configuration files (*.videoconfig) in the raw files folder together with the EEG files.
- 2
Open Analyzer and create a workspace as described in the User Manual (cf. Getting started and handling the program), to import the EEG data into Analyzer. We invite you to watch one of our webinars for a quick introduction to Analyzer concepts.
- 3
Open the simultaneously acquired EEG data and select the Video Add In (via Add Ins > Plug In > Analyzer Video).
Due to the large size of the video files, it might be necessary to store video files separately from the corresponding EEG files. In such cases, you can use the configuration file to indicate the file path of the video. Simply open the configuration file (*.videoconfig) in any text editor and provide the corresponding information as illustrated in Figure 3.
Figure 3: Specifying the video file location in configuration file.
The visualization window, will, by default, contain the video panel at the top and the EEG waveform at the bottom. You can, however, right-click on the video’s title bar and choose Float from the context menu, so that you can resize the panel as desired (see Figure 4).
Figure 4: Synchronized video and EEG view, with the floating video panel and their respective navigation sliders. The test data demonstrates synchronized playback of video-EEG, with the EEG displaying an artifact when the participant touches the electrodes (see the timestamps in the video panel and at the status bar).
How to simultaneously navigate the EEG and video data?
You can seamlessly navigate the EEG and/or video data using either of the sliders (see Figure 4). You can use the Play and Stop buttons to play, pause, stop, and re-play the video data.
If the EEG is Master checkbox is enabled: navigating through the EEG waveform involves clicking within the EEG view and dragging the EEG slider (indicated by the vertical blue line in Figure 4). Instead of dragging with the mouse, you can also use the keyboard’s left and right arrow keys. This action simultaneously adjusts and updates the position of the video slider (located within the video panel as depicted in Figure 4) to correspond with the current EEG position.
If the Video is Master checkbox is enabled: navigating through the video data involves dragging the video slider (located within the video panel as depicted in Figure 4). This action simultaneously adjusts and updates the position of the EEG slider (indicated by the vertical blue line in Figure 4) to correspond with the current video position.
If you accidentally drag the slider when the corresponding checkbox is disabled (i.e., dragging the video slider while the Video is Master checkbox is disabled or dragging the EEG slider while the EEG is Master checkbox is disabled), the current position of the EEG and video sliders will be out of sync. You can re-synchronize by clicking on the Sync. EEG button
.
.You can complement the functionality of the Video Add In by incorporating another Add In called Marker Navigation (via Add Ins > Tools > Marker Navigation). This allows you to easily jump to a specific EEG marker position and inspect the corresponding video data at that same moment. You only need to specify the Marker Type/Description and use the next (>) or previous (<) buttons (see Figure 5). This avoids the manual process of scrolling through the EEG.
Figure 5: Navigate to the desired marker position using the Marker Navigation Add In.
We hope that this overview serves as a solid foundation for your journey into the combined video-EEG analysis. Should you have questions about functionality of the Video Add In or questions around data analysis, please don’t hesitate to reach out to us at support@brainproducts.com. We will be happy to help!