# The Playback Control window

Show/hide the Playback Control window

Click the Show/Hide button on the toolbar and select Playback Control to show/hide the Playback Control window.

Use the Playback Control to:

▪Start and stop trials, and add/skip trials in your list.

▪Position video files on the frame you require (when you track from video files).

Playback functions

For the description of the playback control buttons, see Playback Control, Acquisition and Visualization.

note Clicking the playback control buttons does not result in acquiring data!

DDS (Detection determines speed)

Detection determines speed is only available if you track from video. When you select this option, during acquisition images from the video file are analyzed at the maximum speed that the processor can handle. EthoVision varies the speed depending on how much data it has to process at each frame.

We recommend to keep this option selected, so that video frames are not missed with high processor load.

important Do not select DDS when you score behaviors manually or determine thresholds.

Why use Detection determines speed?

▪To track faster when EthoVision XT can process images at a speed higher than the regular playback speed.

If you select this option, the program tracks at a speed higher than normal (1x). For example, when you use a fast detection method such as Gray scaling.

▪To ensure that no sample is missed when tracking is very demanding.

If you select this option, when EthoVision cannot keep up with the regular playback speed it tracks at a speed lower than normal (1x) in order not to miss any sample. For example, when you track from high resolution video, in many arenas and with a high sample rate combined with a detection method that requires significant processor time.