Institute for Language Sciences Labs


How to (re)code videos offline in the Babylab

Last updated on 28 November 2017 by W.J. Doedens

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This page aims to give you a step-by-step description of how to recode videos that have been recorded in the Babylab.


If you have any questions or comments after reading this how-to, please contact our babylab manager Desiree Capel.
If you encounter problems with executing the steps in this how-to, please refer to the frequently asked questions page for this topic first.

Step-by-step guide to (re)coding videos offline in the Babylab

Support and opening hours

  • Access to the Babylab is restricted. Contact Desiree Capel for details.
  • Back-up all your video files. Make sure the files you will be working with are not the only versions you have.
  • For details on opening hours of the labs, see this page.
  • For converting and coding videos, VLC and Java 1.6 (or later) are required.

Shuttling scripts and data to other computers

The Babylab is primarily meant for running experiments; you are expected to do some of your experiment preparation, and all of your data analysis, on computers outside the lab or in room K.06. Use the ILS Labs data server to move your data to other PCs, and to safely store it.

Most videos are compatible with the video coding software, but you might encounter a video that is not compatible, especially if it has been recorded in the Babylab (K.11). The software automatically performs a software check. If you receive a notice that the video is not compatible, you should convert your video. If you receive a notice that the video compatibility could not be checked, you should check for the compatibility manually. See this how-to for instructions on how to check the video compatibility manually.

Take this step very seriously. Video’s that are not compatible will give the wrong video time information, meaning the results will be off by a long way

If you have to convert a video, check the video converting how-to

The ILS Labs Video Coding System can be run on both Windows and Linux computers. Apple products are not supported.


If you have a Windows computer, the easiest way to get the program running, is by installing it. If you don’t have install rights, jump to Running the program if you have no install rights.

To install the software on your computer, download the file ils-OTS_VideoCodingSystem_Installer.exe from our GitHub page. The link to the file is located at the bottom of the page.
Click the file to download it, then double click the downloaded file to launch it. Just follow the instructions, and the program will be installed to your computer automatically. Afterwards, you can start it from the start menu or from your desktop (it’s called ILS Labs Video Coding System)

Running the program if you have no install rights

If you are using a computer that doesn’t have VLC installed (in the regular way) and to which you can’t install new software, you can use the launcher file.
This will most likely be the case if you are working on University computers that aren’t situated in our lab.
Go to our GitHub page, scroll to the bottom and click the file UiL-OTS_VideoCodingSystem_PortableLauncher.exe by clicking it. Then double click the downloaded file. This will automatically set up everything you need to start the program (it may, however, take a while, so don’t shut the computer down if nothing seems to happen at first).

Java is still required to be pre-installed. This is the case for all University computers, but if you are working on a computer that doesn’t have Java installed, you need to find another computer, or use the installer if you can. If you’re not sure if Java is installed, just download the installer or the launcher, and if Java is not installed, the computer will tell you.

The old fashioned way

If you don’t want to use the exe files, download the VideoCodingilsOTS.jar file from our GitHub page (at the bottom of the page) and save it to your disk.

  • Double click on the .jar file.
  • If you get an error message:
    • Click on ‘I already have VLC’
    • Click on ‘Specify VLC path’
    • Look up C:/Program Files(x86)/VideoLAN/VLC (if you installed VLC in a different location, you have to provide that location. See the instructions in the warning dialog).
    • Click on ‘OK’
    • Click on ‘Okay, I’ve got it’
    • Double click on the .jar file again. The program should now start without issues.


If you have a debian based Linux distribution (e.g. Ubuntu), you can use the debian package to install the software to your computer. For 64 bit computers, download the amd64.deb file from the GitHub page, for 32 bit computers, download the i386.deb file. If you are unsure which to pick, download the i386.deb version.

On some computers, you can double click the downloaded debian package and it will open software which helps you install. Just wait till “ILS Labs Video Coding System” is shown and click “Install” (or “Upgrade” if you have an older version installed).

If that does not work, you can use the command line. Open a terminal and navigate to the location where you saved the debian file. (Using 32bit version 2.1.3 as an example,) type:

dpkg -i ilsOTSVideoCodingSystem-2.1.3-i386.deb

In the window that opens, you can create a new project, or open an existing one. To create a new project, fill out the required information:

  • Project name (the project will be saved under this name, with the .ils extension, so you can open the project later on)
  • Project location (where to save the project)
  • Video (Click the text field and select the video you want to code in the window that then opens)
  • Experiment name/Experiment ID/Researcher ID/Participant ID
    • Tick the box if you want this to be included in the output .csv file
    • These are not required, and you can change them later on
  • Timeout
    • Tick the box if you want a trial to time out after a certain number of msec. Fill out the number of msecs (default is 2000 msec. Timeout will be registered as soon as a child has looked away from the target at least the amount of msec provided).
  • Click “Create new project”

Once you’ve created a project, a new window opens where you can start coding. Press the spacebar or “play” to start the video.

The area on the top of the screen is where the video plays. Below that, you have a row of buttons for playing and pausing the video, and to go back or forward one frame at the time. To the right of the video buttons are the trial/look buttons. Below that is a timeline, that indicates where you are in the video, and where the trials and looks that you have previously created are. These trials and looks appear as boxes on the timeline, which you can zoom in to and scroll over, and which provide quick access to all kinds of manipulations to the trials and looks and where you can see the duration of a look or the total look time of a trial. If a comment is present, that is also displayed in the box for that item. If you want to see this information without zooming in, simply hold your mouse on the trial or look you wish to study.

You can move forward and backward in the video by pressing play/spacebar, using the arrows on your keyboard and moving the indicator on the bar.

  • Press “new trial” to start a new trial
  • Press “new look” to start a new look within a trial
  • Press “end look” to end a look.
  • Press “end trial” to end a trial.

If a look is created inside a trial more than the number of milliseconds provided as the timeout after the previous look is created, this look and all subsequent looks are tagged as a timeout. Looks that are a timeout are ignored when calculating the total look time for a trial. The timeout can be disabled, enabled or changed manually.

You can add a comment/tag to a look or trial as well:

  • Click on the trial or look in the timeline with the right mouse button
  • Click on “Add a comment” in the menu that appears
  • Enter the comment in the text field that appears to add a comment, or change or delete the text to alter the comment

Several features that may be useful during coding are:

  • Removing a trial or look: You can remove a certain look or trial if it is incorrect, or you can remove all looks inside a trial, without removing the trial, if you want to recode that specific trial. Click on the trial or look you wish to delete (or alter) with the right mouse button and click the menu item that indicates what you want to do. Note: removing a trial also removes all looks inside that trial.
  • Go to a trial or look: You can go to the start of a look or trial, by clicking with the right mouse button on the specific look or trial in the time line, and selecting “Go to beginning…”
  • Show data preview: In the menu, go to Project –> Show overview (Ctrl + O) to show an overview of the data you gathered so far. This overview shows all the looks and trials you coded, including the duration of each look, and the total time of all looks in a trial. If you have timeout enabled, all looks that come after the first timeout are ignored in calculating the total look time
  • Change meta information: In the menu, go to Project –> Experiment Settings (Ctrl + E) to change the meta data (such as the name of the experiment, the ID’s of the experiment, researcher, participant) and to enable, disable or change the timeout.
  • Change quick keys: You can use keyboard shortcuts for playing and pausing the video, going back or forward a single frame and creating and ending trials and looks. If you want to check what those shortcuts are, or change them, use the menu to go to Help –> Quick Keys. Click the shortcut you wish to change and hit the keyboard button you want to replace it with.
  • Export your project to CSV: By clicking the File menu and then Export Project to CSV (Ctrl + Alt + E) you can export your project to CSV, for further processing the data. There are two options provided in the export window: CSV File (Project) and CSV File (Overview).
    • Project: The project option generates a CSV file where each trial is on a single line. The total look time (of valid, not timed out looks) is given for each trial, but the looks itself are not exported
    • Overview: The overview option generates a CSV file much like the Show overview window displays. Each trial and look is exported, with start- and end times for each trial and look, the total time of each look and the total look time (of all valid, not timed out looks) for each trial. If you want more detailed data for analysis, use this option.

To cite the ILS Labs Video Coding System, you can use the following format (APA style).

De Mooij, A.J. (year). The ILS Labs Video Coding System (Version version) [Computer software]. Institute for Language Sciences, Utrecht University. Available from

The version you are using can be found under help –> about.