OFO algorithm

[yoyochan]

Hi,

I am learning the optical flow algorithm recently.And have several problems.I hope someone can help me. Thanks!

In ArduEye_OFO_v1,ArduEyeOFOClass::IIA_Plus_2D ,using a simplified version of Mandyam Srinivasan's. I haved read the algorithm,and know the scale in the program refers the △xref.

But why in the program ArduEye_stonymanUnoRocket .cpp scale=200? I have checked the pixels distant in Stonyman is 25um.

Also have the questions in LK algorithm.In opencv,the algorithm is used to calculate the speed,

and in the ArduEye_stonymanUnoRocket.cpp it's used to calculate the distance.So why scale is also 200? Shouldn't scale refers to time?

[yoyochan]

I also want to ask .Dose the scale means Magnification ?

[Geoffrey L. Barrows]

Yes- that is it.

[Geoffrey L. Barrows]

Yoyo,

The "scale" variable is a basic scaling parameter. It was selected so that reasonable values could be obtained when using fixed-point arithmetic, which is faster than floating point arithmetic especially on an Arduino. It really doesn't have any meaning beyond that. You can change it to a different value or, if speed is not an issue, move to all floating point arithmetic.

Geof

[yoyochan]

I got it.So what is the unit of the result which is calculated by IIA_Plus_1D? I found the background affects the result .