opticFlow with angular/circular data

2 次查看（过去 30 天）

Vishnu Sreekumar 2019-6-11

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/466519-opticflow-with-angular-circular-data

评论： Vishnu Sreekumar 2019-6-11

I'm trying to use opticFlowHS with angular data (phase data, -pi to pi). The trouble with using MATLAB's built-in opticFlow function is that gradients are calculated using normal differences whereas for angular data, you need to calculate circular differences when computing gradients. Otherwise, the algorithm will fail anytime there are phase slips. I learned this the hard way (realized it just before I was about to submit a journal article for publication).

Is there any workaround available? Is this something that the folks at MATLAB can help me with?

2 个评论
显示无隐藏无

Adam Danz 2019-6-11

I think you mean opticalFlowHS. Just curious, is it that you're computing optic flow from angular velocities or are you computing optic flow on a curved surface such as the retina?

Vishnu Sreekumar 2019-6-11

Yes, opticalFlowHS is indeed what I meant. Not from the retina, from the brain where the "pixel intensity" data I input are instantaneous phase values (wrapped from -pi to pi) from EEG time series.

请先登录，再进行评论。

请先登录，再回答此问题。