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Camcorder Element

Modified on 2016/05/08 11:51 by Maria Categorized as Data Collection, Elements

Element Icon Camcorder
Category: Monitoring AddIn: Base Elements
Creator: OkazoLab Team Scope: Global
Owns Snippets: no Usage: Background

Element actions aligned with different epochs of the parent event

InitializedThe element starts capturing video/audio
RunningThe captured video is streamed into a file
DeinitializedThe element stops capturing video/audio


Generic Properties

NameDescriptionConstraintsValue TypeUpon Change
Video DeviceDefines a video device for capturing. A drop-down selection list shows all devices available in the system. String
Device SettingsOpens a window with OS settings of the selected video device.
Audio DeviceDefines an audio device for capturing. A drop-down selection list shows all devices available in the system.String
Output FolderOpens the dialog for selecting a local folder that will hold all recorded videos. If no or relative path is defined, the videos will be saved relative to the location of the experiment file.

Custom Settings
Use Custom SettingsDefine whether custom frame size and framerate are used for video capturing. The custom settings are only applied, if the resolution and framerate values are supported by the selected video device. Otherwise, the device's default settings are used.Boolean
ResolutionDefine the resolution of a captured video. The video frames can be scaled to any size in rendering, but choosing a larger resolution improves rendering quality with a cost in performance.clSize
Frame RateDefine the custom framerate of video capturing, in frames per secondInt32
Runtime Status
Save Marker NowRuntime snippet action that that adds a sync text marker into the recorded video. Use the action in the code snippets, e.g. 'SaveMarkerNow=\"Trial Onset\";'. In order to end the marker, save an empty string: 'SaveMarkerNow=\"\";' String
Actual SettingsReturns the actual resolution and framerate of the current video capture. The property is updated at the start of every experiment run.String

+=== Properties inherited from clElement === Inherited properties of clElement
NameDescriptionConstraintsValue TypeUpon Change
Is EnabledIf set to false the element is completely omitted when the experiment is run.Boolean
TitleTitle of the element.String

Camcorder element allows synchronized video recording using any computer video device, e.g. web-camera, at the background of experiment.


The camcorder element streams a video into a file (one per experiment run) together with custom text markers that can denote experiment events or carry other information. Use Windows Media Player for playback of recorded videos to unsure visibility of the markers.

Practical Use

  1. Add new Camcorder element to any event in your experiment
  2. Click on the Camcorder element and select video and audio devices for capturing.
  3. Select a local folder for storing the captured videos via the 'Output Folder' property of the Camcorder element
  4. If you want to add custom text markers in a captured video at runtime, add a proxy variable to the 'Save Marker Now' property of the Camcorder element
  5. Captured video will be streamed in a new file each time as you run your experiment. The file name is composed of the run time and title of the experiment, e.g. "2014-04-11 01_52-camcorder.wmv"
  6. In order to record a marker into the video file, assign a custom text value to the 'Save Marker Now' proxy at the selected moment in your experiment (see the code example below).

SaveMarkerNow="Fixation Event | Trial"+TrialNumber;


  • We recommend to use Windows Media Player for viewing recorded video files because other video players may not be able to show the embedded text markers.

  Name Size
- CamcorderIcon.png 3.40 KB

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