» CamShiftTracker (FreeFrame DShow9)
This site relies heavily on Javascript. You should enable it if you want the full experience. Learn more.

CamShiftTracker (FreeFrame DShow9)

Help
Author
Info This node comes with the addon pack. Get it here.

Here you are supposed to see an image (rendered with SVG) describing the pins of this node. However, this does not work with Internet Explorer. You may want to consider using another browser, like FireFox, Chrome, Safari or Opera that do support SVG.

Credits
Warnings
Bugs

related discussions

start a forum thread about this node

about CamShiftTracker (FreeFrame DShow9)

open source

usage

When you use CamShiftTracker the most important step is the fine tuning of the tracking parameters.

These are:

  • Size and orientation of initial ROI
  • Saturation min, Value min and max

To achieve an optimal tracking output, these parameters have to be adjusted to the lighting situation of the video scene (or vice versa).

If possible, turn off automatic gain control (AGC), automatic brighness ajustment etc. on your camera.

During fine tuning of the parameters you should have Show Backproject set to 1, so you can see which pixels of the image are considered as belonging to the object (i.e. those which are white). Also, set Show ROI to 1, to see the search frame.
When nearly all pixels in the area of the object are white and the rest of the image is black, you're done.

Like a good linear minimizer, adjust one parameter at a time, then continue with the next one. Playing around will give you a feeling for this...

Be sure that your object lies in or, ideally, fills the initial ROI when you initialise the tracker by banging Init Tracker. You will get the best results by using a white background. Since white (background) pixels have a very low saturation, you can kick 'em out by increasing the 'Saturation min' pin value.
Adjust Value min and Value max to the range of your object brightness:

OBJECT BRIGHTNESS VALUE MIN VALUE MAX
dark very low V1 (near 0.0) low V2
bright high very high V2 (near 1.0)
different shades low high

After each tuning step, init Tracker again to submit the tracking values and refine the object search.

If all that doesn't help, you might have to improve the lighting situation.
Think about illuminating the object with a lamp, or adding a diffuser if the video image is too dark and the colors don't come out right.

anonymous user login

Shoutbox

~42min ago

LineKernel: @evvvvil yes exactly what i was looking for.I had forgot the name, that's what happened when you dont use v4 for many years

~45min ago

evvvvil: @linekernel: plug your lfo into waveshaper with "shape pin" as SINE. Or ask your old lady to count from 0 to 1 with a smooth voice

~1h ago

LineKernel: dont remember in what i should put lfo to get something oscillating like sin instead of saw ?

~21h ago

metrowave: @elektro, very fresh! love it.

~2d ago

everyoneishappy: @ele that's very nice indeed

~2d ago

elektromeier: thanks! the markers are not really invisible, you can see them easily if you want but they are pretty unobtrusive.

~2d ago

vasilis: @elektromeier Amazing!! Keep up the good work

~2d ago

moco: @elektromeier nice one! are you using invisible IR markers?