» 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

~39min ago

AndyC: Can anyone recommend things to do here in Berlin in the next 10 days?

~1h ago

catweasel: mrboni I suggest on having matrox crap software on 1 pc, config on that one and just plug it into a charger when in use

~2h ago

esnho: https://www.youtube.com/watch?feature=player_detailpage&v=c9gBcPWh0pU#t=3 now also the change while moving works. thanks vux for the insipiring patches

~4h ago

antokhio: it's on matrox website

~9h ago

mrboni: arrrrg! th2go requesting firmware update on win 8.1 cant find new firmware anywhere. anyone experienced this?..

~9h ago

nothingtolose: how to use gesture,circlegesture,swipegesture

~14h ago

joreg: how ql is that: on the downloads/alphas page you now get a list of changes for each build..

~22h ago

rrrr: @fleg German resident or German citizen?