Knowledge Base

Acquiring and Managing Trials

Re-Enable a Skipped Trial

1. Locate the trial and change its Acquisition status from To Skip to Planned. Make sure that you do this for all the arenas you want to use in that trial.
2. Go to the Acquisition module and carry out the trials as usual. After that, its Acquisition status changes from Planned to Acquired.

Notes

• To skip a trial other than the current one in the Acquisition screen, open the Trial List. Click the Show/Hide button on the toolbar, select Variables and make sure Acquisition status is selected in the Show Variables window. Locate the trial you want to skip, and change the Acquisition status for that trial from Planned to To Skip.
• You can also skip arenas within a trial.

Acquire Data for Some Arenas, Not Others

Use this procedure to acquire data only in the arenas that contain subjects. For example, for Trial 32, a few arenas in a well plate are empty, but you want to track the subjects in the remaining arenas.

1. In the Experiment Explorer, click Trial List.
2. Locate the Acquisition status column. If it is not present, click the Show/Hide button on the toolbar, select Variables and select Acquisition status.
3. Locate the trial for which you want to skip arenas, and change the Acquisition status for those arenas from Planned to To Skip.
4. Carry out the trials as usual.

Notes

• After acquisition, the Acquisition status of the skipped arenas changes from To Skip to Skipped.
• You can no longer acquire data for the skipped arenas because the trial itself has been acquired. To acquire data for those arenas, add a new trial and acquire data anew.

Redo a Trial

Use this procedure to record video or track data once again for a trial previously acquired.

Important: When you redo a trial, you remove the tracks, the events scored manually and the trial control event data (including hardware device data) recorded during that trial.

1. In the Acquisition Settings window, under Options next to Clear and redo a trial, click the Select button.
2. In the Redo Trial window, select the trial that you want to redo.
3. Select one of the options, then click OK.

   When tracking from video files:

   • Clear tracks. The tracks are deleted. Choose this option if you want to redo the trial using a video file different from the current one.
   • Clear tracks but re-use the video reference. As above, however the link to the video file is retained. You can open Acquisition to track from that video file.

   When tracking live:

   • Clear tracks. The tracks are deleted. This option is available if you acquired tracks without saving video.
   • Clear tracks but re-use the video. Deletes the tracks but not the video file used to acquire those tracks. You can then track again from the video file.
   • Clear tracks and video. Deletes the tracks and the associated video so you can redo the trial anew.
   • Clear video. Clears a trial that has video only. You can then record a new video and acquire tracks. This is the only option available if you acquire data by saving the video first.
4. In the Acquisition Settings pane, under Method:
   • If you cleared a trial that used a video file not made with EthoVision XT, choose Track next planned trial. This is the option for redoing the trial from that existing video file.
   • If you cleared a trial with a video file made with EthoVision XT and deleted that video file, choose Track next planned trial. Alternatively, choose Save video only, track later to record a new video file for that trial without tracking.
   • If you cleared a trial with a video file made with EthoVision XT but kept the video file, choose Track next saved video file. With this option you redo the trial for that video file.
   • Choose Track all planned trials if you have a list of planned trials and you want to acquire data for all of them in one go.
5. Under Settings, next to Trial, verify the number of the trial you are about to acquire. The Video box shows either Live video or the video file you will track from, depending on the options chosen above.
6. If necessary, click the button next to Video and select the video file to track from.
7. Click the Start Trial button in the Playback Control window to start the trial.

Notes

• The options available next to Select action vary depending on how you acquire the trials. For example, if you track from pre-recorded video files, then only the first two options Clear tracks and Clear tracks but re-use the video reference are available.
• Before redoing a trial, always check in the Acquisition Settings pane under Method which option is selected, and under Settings the video file you are going to acquire the trial from.
• If you track from video recorded with programs other than EthoVision XT and you want to delete the video file corresponding to the trial you want to redo, you must delete the video manually.

Rename or Delete a Trial

To Rename a Trial

Trials are given default names depending on the order they are added in your Trial List: Trial 1, Trial 2, etc. (first column of the Trial List). To rename your trials, edit the Trial name variable in the Trial List.

1. Choose Setup > Trial List.
2. Click the Show/Hide button on the toolbar and select Variables. In the Show Variables window, select Trial name.
3. In the Trial name column, double-click the cell corresponding to the trial you want to rename, then enter the new name.
4. The name under Trial is changed automatically, matching what is entered under Trial name.

To Delete a Trial

Deleting a trial removes all the tracks and external data files (if these have been imported in EthoVision XT) from your PC. To delete a trial, in the Trial List, click a trial and press Delete, or right-click a trial and select Delete Trials.

Notes

• If you have tracked from video files generated with EthoVision XT, you are asked whether you want to keep the video file associated with the trial or delete it too.
• If you have tracked from video files generated with programs other than EthoVision, the video file associated with the trial is kept on your PC.
• To delete multiple trials, select the trials in the first column of the Trial List, then press Delete or right-click and select Delete Trials.
• In a multiple-arena experiment, you cannot delete tracks acquired in some arenas within a trial. You can only delete all tracks, that is, the entire trial.
• If you delete a trial and then add a new one, it is not given the name of the deleted trial. For example, if you have 10 trials in your Trial List and you delete Trial 4, when adding a new trial it is named Trial 11. To avoid this, do not delete the trial but clear it: right-click the trial in the Trial List and select Clear Trials.

Rename or Delete a Generated Video File

Video files recorded within EthoVision XT are given the same name as the corresponding trial: Trial 1.mpg, Trial 2.mpg, etc. If you want to rename or delete a video file, you must first delete the corresponding trial. If you want to rename a video file without deleting its trial, make a copy of the video file with File Explorer and give this copy the new name.

1. Choose Setup > Trial List.
2. In the Trial List, right-click the row corresponding to the video you want to delete and select Delete.
3. In the window that appears:
   • Choose Rename generated video files for backup if you want to rename the file and delete the trial.
   • Choose Delete generated video files if you want to delete the video file and the trial.

   Important: In either case, the tracks and the external data files associated with that trial will be deleted.

4. Click Yes to confirm.

Use a Remote Control to Start and Stop Acquisition

Use this procedure to start and stop data acquisition when standing far from the EthoVision XT computer. You need a remote control with Page-up (<) and Page-down (>) buttons, such as those typically used for PowerPoint presentations.

1. Close EthoVision XT.
2. Browse to my.noldus.com, log in or register. Click Downloads, then EthoVision XT, then Drivers and Tools, and download the file for remote control. Save remote_control.zip to your EthoVision XT computer.
3. Extract and double-click the remote_control.reg file. When a message appears, click Yes. You can now use the remote control.
4. Switch on and connect the remote control. This is usually done by plugging a USB receiver into the EthoVision XT computer.
5. Start EthoVision XT and choose Acquisition > Open Acquisition.
6. To start a trial, press Page-up (<) on the remote control.
7. To stop a trial, press Page-down (>) on the remote control.

Notes

• Signals from the remote control will only be recognized:
  • While acquiring data, and if the trial is not finished yet.
  • When you are not entering independent values.
  • When you are not browsing through the video.
• For earlier versions, download the full installation package and look for the Remote Control folder under Utilities.
• If your PC is connected to a network through Wi-Fi, you could control EthoVision XT from a smartphone using one of the apps available, provided that the network's security settings allow communication.
• If you have the USB-IO box and the TTL Port Tester PTTB-001x, you could have EthoVision XT start tracking when you press the button on the TTL Port Tester. To do so, connect the TTL Port Tester to a TTL port of the USB-IO box. In the Trial Control Settings, create a condition based on the TTL Port Tester that becomes true when button 1 is pressed. Place the condition box between the Start Trial box and the Start Track box. Note that with this solution you must click the Start Trial button in EthoVision XT, which then waits for the button press.

Export Track Data Live

Use this procedure to create a sample interface that exports track samples in real time during data acquisition.

To enable external data export, you can write a DLL (COM DLL, also known as COM component) in C++. The DLL should implement the sample interface and should include instructions for processing the samples, for example:

• Write the sample data to a local file.
• Send the sample data over the network to an external application.

If you need help writing the code for your DLL, please contact Noldus.

Notes

• The sample interface is specific to the EthoVision XT version you are using.