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Hello,

I am working with 6 v100:R2 cameras situated in a (roughly) 4x4' box. I'm using the facial markers (3mm) to track an object.

My main problem is that when I open the data file some of the dots are shuffled in quick succession. For example, if I only had 3 dots, at some time in the recording (say some arbitrary 4 frames) the positions would be given by:
123
231
312
123

The only thing I can think of is that the dots are too small and too close together for the volume I'm using. I'm also having a problem with dots disappearing and reappearing. I'm only using 5 markers but sometimes the output jumps up to 8 points.

Any ideas?

P.S. Sometimes when the dots disappear and reappear again their new positions seem like they don't get tacked on to the end of the .csv file but instead are thrown in the middle of the frame information arbitrarily (while changing all point cloud marker id's). Is there any way to edit how the software arranges it's output?

Thanks.

What version of Tracking Tools are you using?

The CSV will always be arranged frame by frame. If there are dots appearing in the wrong spot, it may be a phantom marker. scrub your timeline to the frames around where it appeared and go forward/backward to see if a marker appears where there shouldn't be one.

Thanks for the reply.

I am using the newest version of tracking tools.

I think my post may have been confusing. I know the csv file is arranged frame by frame, the problem is that the dots get shuffled throughout the columns. Say I'm just looking at the position columns for the third dot, if I scroll through the frames I will have a long part which is truly the third dot. Then suddenly the first, second, and third dot positions will be shuffled frame by frame. Like so:

3
3
3
2
1
3
2
1
3
3
3

(each number represents three columns (x,y,z) for each dot).

I'm just not understanding why it would randomly output the positions this way instead of outputting in a consistent manner. I can't scrub the timeline because I have already output the csv file and I'm not sure how (or if) I can import the data back into TT to see what was actually happening.

I appreciate your help.

The order the point cloud markers are represented in isn't necessarily the same each time, because as they move, they change places in the list and attempting to identify markers and place them appropriately would add large amounts of overhead to the csv export function, as well as introduce issues with markers that appear or disappear through time.

The markers should present as X,Y,Z,ID, which allows you to parse the ID a bit more effectively and match markers. It is possible for the ID to change as time progresses due to a number of potential factors, but it's a good place to start.

You can't re-input the CSV into tracking tools, however it's entirely possible (and recommended) to save the timeline file so you can replay it later. Note, when saving the timeline file, make sure you also have a copy of the calibration as well.