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multiple rgbs - Aug 17 at 11:31PM
alex ng
2 Posts

Hello,

thank you for creating this software, it is amazing.

I would like to ask if it is possible to export multiple rgb regions (locations and pixel radius), so that i can import them to another tracker file. They are 29 regions and i am having a tough time creating them from scratch for each file. They are in all videos more or less at the same position.

At the same topic, it would be great if a next version could have in plot view a "compare with" multiple selection, unless there is a way to do it, that i haven't figured out. I am using this to export the lumas of all the 29 regions.

Another thing i would like to ask is, if there is a workaround to the following. I have noticed that when autotracker tracks items that have high rotation and movement along x axis, there is a slight drag of the target and also the trails are somewhat aliased. I understand the latter must be from the square pixel arrangement of the images. Is there a workaround for this? Or is my marker the culprit, not having a clear right hand side to track?

I have attached an image showing two trails, the left one being ok, the right one suffering from the above description.

Thank you in advance for your time.

best
alexandros

Post edited August 17, 2017 at 11:34 PM EST.

Attached File: Capture.JPG


Replies to multiple rgbs

Re: multiple rgbs - Aug 20 6:10PM
Douglas Brown Avatar
Douglas Brown
161 Posts

Yes you can export multiple RGB regions and import them into another tab. To export, choose File|Export|Tracker File and in the dialog select all the items you want to export, then OK. Note  that if all your videos share the same coordinate system (same camera position, etc), you can avoid having to calibrate the videos separately by also exporting the coordinate system. In the tab with the new video, choose File|Import|Tracker File and select everything. I think this will do exactly what you want.

I like your suggestion to be able to select multiple tracks when selecting "Compare with..."   I'll add that to the next release!

Re the autotracker "drag" and "alias" (is this a reference to the scatter in the trail?), I'm afraid the only thing I can suggest is to experiment with (a) the size and shape of the template image and (b) the evolution rate (try both higher and lower rates). Autotracking a rotating object is tricky...

Hope this helps.  Doug

> Re: multiple rgbs
>
> Hello,
>
> thank you for creating this software, it
> is amazing.
>
> I would like to ask if it is possible
> to export multiple rgb regions (locations and pixel
> radius), so that i can import them to another tracker
> file. They are 29 regions and i am having a tough
> time creating them from scratch for each file. They
> are in all videos more or less at the same position.
>
>
> At the same topic, it would be great if a next version
> could have in plot view a "compare with" multiple
> selection, unless there is a way to do it, that i
> haven't figured out. I am using this to export the
> lumas of all the 29 regions.
>
> Another thing i would
> like to ask is, if there is a workaround to the following.
> I have noticed that when autotracker tracks items
> that have high rotation and movement along x axis,
> there is a slight drag of the target and also the
> trails are somewhat aliased. I understand the latter
> must be from the square pixel arrangement of the images.
> Is there a workaround for this? Or is my marker the
> culprit, not having a clear right hand side to track
>
>
> I have attached an image showing two trails, the
> left one being ok, the right one suffering from the
> above description.
>
> Thank you in advance for your time
>
>
> best
> alexandros
>
> Post edited August 17, 2017 at
> 11:34 PM EST.



Re: Re: multiple rgbs - Aug 24 6:17PM
alex ng
2 Posts

oh yes, i feel embarrassed. It was rigth there in export, yet somehow i managed to miss.

thank you for your reply. I leave the coordinate system as is by default, because i manage all orientation, tranformations scale etc in another software.

Now exporting these like you suggested made the workflow tons faster. Thank you for considering the select addition. I believe it will come in handy for many users.

Yes the drag and aliasing is like you said the scatter in the trail. The autotracker "travels", gets dragged away from target due the square pixels, when strong rotation along with xy axis movement takes place. In the end, the best results came out with 5% evolution rate and many keyframes.

By aliasing i mean the same concept as found in 3d renders where jagged edges appear in non horizontal or vertical edges of objects. To bypass this there are some anti aliasing algorithms that make these edges smoother. Though digital cameras have built antialising, so i guess there is not much one can do, since although edges are smooth, they keep changing position and orientation. An algorithm, like the look ahead, that would give more weight to the diagonal-rotation aspect of tracking, rather than the exact pixel matching, would give better results, but have not found any relevant algorithm.

thank you again for your help.

best
alexandros

Post edited August 24, 2017 at 6:19 PM EST.



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