Topic: Delete tracking lines in part of a video


I would like to know if we can do this with kinovea:

I have a video of 5 minutes and I want to draw a line and track it during min 2:30 and 3:00 Then I want to erase the line and continue with the video . At minute 4:11 I want to use to draw and track it again for 20secs and then stop the tracking and erase it again. Is this possible? Because every time I use the tracking for a line, polyline or spotlight it tracks it for all the lenght of the video.

Thank you very much

Re: Delete tracking lines in part of a video

You're right, at the moment it's not really possible to do this.

You can use start/stop tracking to prevent objects from being tracked after the section you are interested in.
When you start tracking, it automatically changes the visibility option from the default fading to "Always visible". (You can change it back but it might become invisible before the tracking section is over.).

In the next version there will be more control over each drawing's visibility/fading. In theory it will allow you to do this as you can keep a drawing visible for a set number of frames but it will be tedious to match duration manually. I'll check how to support such an option in a more friendly way.

Re: Delete tracking lines in part of a video

That would be great . or if you could do an option for frames to fade in and frames to fade out separately. To give you an example if I try to follow a line of 4 defenders during 5 seconds and i put a high number of frames to fade in/out in the line will start to appear very soon.

Hope this helps
Thanks and congrats for the software.

Re: Delete tracking lines in part of a video

This was addressed in version 0.9.2. The drawings are now opaque whenever they are tracked and they fade in/out around the tracked section(s). You can use the custom visibility options to change the maximum amount of opacity and the fading ramp.