Simple red dot tracking in Ae doesn't work

[clement-montreal]

Trying to make a very simple red dot tracking in After effect 22.5.0 Build 53, but the tracker doesn't follow the point at all, even though it looks super simple to do. ?

I made a video to show what i'm doing: simple transform tracking , 2D,

Any advice ?

[P.M.B]

The tracker works by following a point of pixel contrast  (or something like that).

Instead of putting the entire dot inside the tracker view,

try moving it over an edge of the dot so there is both red and grey.

 

[Mylenium]

Check the "Options" button in the tracker panel. By default AE tracks luminance, not color and your grey and the red dot have pretty much the same values or at least not enough contrast.

Mylenium

[clement-montreal]

Thanks for the advice, I followed both of yuors, but none works ..

See video

[Mylenium]

Then perhaps it's those pesky hardware acceleration issues striking again, which would apply to ProRes in particular since there are additional bugs. As a test, try a different format and see if it works. Also turn off hardware acceleration in AE in case this is somehow related to drawing the widget overlays and the display pipeline.

Mylenium

[clement-montreal]

Mystery remains.. I disabled HW acceleration, rebooted the entire pc, re-encoded my Pre Ros into regular H264 / mp4, but still the same problem 😞

I provide the source file just in case someone would like to reproduce

[Josie_]

I did similar a similar project recently, except mine was a cube.

Try using a black solid layer bg first, for contrast. 

and then remove solid after track hopefully successfully done.

[Josie_]

To add further, you could try slowing down the clip also before tracking. 

and then back to normal speed after finished.

[Rick Gerard]

The feature tracker, not it's not a point tracker, has a feature region, the inner box, and a search area, the outer box. The search area must be big enough to find the detail area in the next and previous frame. The Feature must have some detail. A fairly large red dot against a gray background does not have much detail. Your feature region should include the dot and about the same amount of background. The search area should be a fair bit bigger than the maximum movement of the dot.  I got a near-perfect track with this setup:

The project file is included. Understanding how the Feature tracker works helps you figure out which shots it will work on. This is one of the few shots where Feature Tracking work better than Planer tracking in Mocha AE. 

[clement-montreal]

Many thanks for the explanation Rick, I tried expanding the search area as well as including the entire red dot inside the feature area helped, but it still doesn't seem to follow accurately .

My project is actually about following pointer from a Powerpoint presentation ( so that i can change the abckground , loing story)

Enclosed is the video showing the type of tracking I need to do . With a laser pointer moving quite fast sometimes, is it at all possible , even if I let Ae time to process the tracking for a while ?

[Rick Gerard]

You will have trouble tracking the movement of the laser pointer moves as fast as the red dot in your sample video. The search area will have to be so big that it will be hard to find the dot. You might try tracking until the track fails, expand the search area and track one frame at a time to see if the tracker can catch up, then reduce the search area again. In all likelihood, you will have to edit some of the points manually. This is much easier if you open preferences and temporarily turn off viewing the keyframe paths. 

I'm still not completely clear about what you are trying to do. Adding a virtual laser pointer is much easier than tracking one, then putting it in another scene. 

You would be better off animating the pointer than trying to track an existing o e. You can create masks or shape layer paths, set a path keyframe, cut it (Ctrl/Cmnd + x), then set a position keyframe for your pointer layer (Alt/Option + p), then Paste (Ctrl/Cmnd + v). 

Animate the speed graph to get the timing the way you want it, and your pointer is perfect and will respond very well to motion blur. 

Your sample video looks like a composite of a moving shape layer or masked layer on top of a background. It does not look like a pointer in a PowerPoint presentation video. You might want to consider removing the little red dot if you have a laser pointer in a PowerPoint video that was recorded with a video camera. There are several ways to do that.