Knowledge Base

Observe Live and Analyze with FaceReader

Aim

Integrating FaceReader with The Observer XT achieves the following:

• When you start an observation, FaceReader starts analyzing with the selected settings and records a video of the test participant's face.
• When you stop an observation, FaceReader stops analyzing.
• The FaceReader analysis results are automatically imported into The Observer XT and synchronized with the events.
• The recorded video is automatically linked to the observation and synchronized with the events and FaceReader analysis results.

Prerequisites

• You have FaceReader 8 or higher. For earlier versions, the procedure may be different; consult the documentation of that version.
• The Observer XT, FaceReader, and N-Linx Server are installed on computers that are in the same network.
• Your license for The Observer XT includes the External Data Module.
• FaceReader is open.
• You created a project with at least one participant in FaceReader.
• You selected a default camera in FaceReader and selected to record video.
• In the FaceReader Data Export Settings, you selected Enable N-Linx and entered the IP address or computer name of the computer with N-Linx Server.
• If FaceReader, N-Linx Server, and The Observer XT do not all run on the same computer, you created exceptions in Windows Firewall for the default port 5672 on all computers. If you chose another port, you created exceptions in Windows Firewall for that port.
• If FaceReader and The Observer XT run on different computers, you made sure that the computer with The Observer XT can access the FaceReader video files. See Access the Video Files on Another Computer.

Procedure in Short

The detailed procedure to set up FaceReader with The Observer XT is present in the topic FaceReader with The Observer XT in the FaceReader Help. Press F1 in FaceReader to open it.

In The Observer XT

1. Choose File > Preferences > N-Linx Settings.
2. Select Use N-Linx Server to connect with other applications.
3. In the N-Linx Server address field, enter the IP address of the computer with N-Linx Server. Leave the default entry Localhost if N-Linx Server is on the same computer as The Observer XT.
4. In the N-Linx Server port field, leave the default port 5672. Ask your system administrator for assistance if this port is used by another program.
5. Click Test Connection. If connection with N-Linx is found, the Status will change to Connected. If not, enter the correct settings and click Test Connection again.
6. Click OK.
7. Choose Setup > Project Setup.
8. Select Live Observation. The Devices window now opens. If not, click the Devices button.
9. Select the checkbox in front of FaceReader - [computer name] and click Edit Settings.
10. Select the FaceReader settings for your experiment. Optionally, enter a name in the Identify Device As field. This name will be added to the Coding Scheme as Subject and allows you to control multiple instances of FaceReader running on different computers with The Observer XT.
11. Click OK and select the checkbox in front of the line FaceReader - [computer name].

In FaceReader

1. Choose File > Set Default Camera, choose your camera, and select the option Record.
2. Choose File > Settings > Data Export.
3. Under External Communication (N-Linx), select Enable N-Linx.
4. If FaceReader and N-Linx Server run on the same computer, leave the default address Localhost in the N-Linx Server Address field. If the programs run on different computers, enter the IP address or computer name of the computer with N-Linx Server. To find that name, open the Control Panel and choose System.
5. In the N-Linx Server Port field, leave the default port 5672. Ask your system administrator for assistance if this port is in use by another program.
6. Under Export (Detailed Log, ODX, N-Linx and API), choose which data to send to The Observer XT.

Carry Out Observation

When you carry out an observation, FaceReader analysis starts. You can follow the data transfer in the N-Linx Data Transfer window.

When you stop the observation, the FaceReader data are imported into the observation. The name entered in the Identify Device As field is imported as Subject in the Coding Scheme. The video is also imported into The Observer XT automatically.

The N-Linx Data Transfer Window

Each row in the window represents a data stream with the following columns:

• Stream: The name given in the Identify Device As field combined with the name of the data stream.
• Messages: The number of times information was sent from FaceReader to The Observer XT.
• Error: An error can occur when a package contains data that The Observer XT cannot handle, for example when time information in the package is incorrect. Check the setup if many errors occur.
• Last Error: The last time an error occurred.

Notes

• See the FaceReader documentation for details on how FaceReader data are imported into The Observer XT.
• Consider entering the name of the test participants in the Independent Variables list instead of defining it as Subject. See Independent Variables.
• When you enter a name in the Identify Device As field, this name is added as a subject to the Coding Scheme. When manually scoring events, The Observer XT expects that for each event you first score a subject and then a behavior. Define a subject in the Coding Scheme, then choose Setup > Project Settings > Scoring Options and select Auto-Record Subject. You then only need to score the subject once at the start of the test.