SwisTrack/The Timeline

At at the bottom of the main window, SwisTrack displays a timeline with an evolution of its state (running, not running, productive mode, normal mode) and the frame processing steps. This not only allows you to see at a glance what Swistrack is doing, but also to find out where your CPU power is burnt.

By default, SwisTrack records all important events for approximately one second, and displays them afterwards. Hence, what you see in the timeline corresponds to what SwisTrack was doing one second ago.

Elements on the Timeline

edit

The following elements are drawn on the timeline:

  • The ruler in the background indicates the milliseconds (ms) from the time recording of that particular timeline has started.
  • While SwisTrack is running (Run button pressed), the otherwise white background changes to light gray.
  • The lower third of the bar indicates whether SwisTrack is in testing mode (gray) or productive mode (green).
  • The blue boxes in the middle represent the steps. Each box corresponds to the processing time of one component. The box of the selected component is highlighted in red.
  • Black vertical lines indicate leap times, but only few components set leap times.

Changing View and Update Rate

edit

The context menu that appear if you right-click on the timeline allows you zoom in and out. This is useful to check out the timings more precisely. You can also drag the timeline left and right with your mouse pointer.

The same context menu also allows you to choose between three update rates: 10 seconds, 1 second (default) and manual update. The 10 second update rate is useful when working with low trigger frequencies. The manual update option allows you to define start and end of an acquisition by double-clicking (anywhere) on the timeline. Double-clicking actually stops the acquisition to displays the acquired events, and starts a new acquisition at the same time.

Note that SwisTrack only records the first 1000 events per acquisition. Hence, when using long slow update rates, SwisTrack may display a "Timeline memory exhausted." message in the timeline.

Saving the Timeline

edit

To save the timeline, right-click on the timeline and choose "Save timeline as ...". The timeline is stored as a text file, with one event per line. Each event contains the following information, separated by tabs:

  1. Time (seconds from acquisition start, double precision)
  2. Type of event (string)
  3. Component name (string), if the event is associated with a component

Speed Considerations

edit

Recording events has a very low CPU overhead and therefore cannot be switched off. If you want to switch off drawing the timeline, simply switch to manual update mode.