Range Disparity Feature

ynjiun

Before requesting support, please see: https://docs.luxonis.com/en/latest/pages/support/

I wonder if the current DepthAI can support "Range Disparity".

A Range Disparity is defined as: Given a range of disparity (d1,d2) of a pixel, the disparity computation will output the best match disparity within (d1, d2). That is the "Range Disparity" would only search the lowest cost disparity in the range of (d1, d2).

So let's define D1 and D2 map for left image. That is, D1 is same dimension as left image with different d1 value for each pixel. Likewise, D2 map has d2 value for each pixel.

Disparity = RangeDisparity(left, right, inputConfig, D1, D2)

The trivial case which the current DepthAI already support is the constant range for each pixel say from 0, to 96..

But for RangeDisparity, each pixel can have different (d1, d2) range.

Please let me know if you have any questions regarding the definition of Range Disparity.

Thank you for your help.

erik

Hi ynjiun ,
Maybe first start with the why - so why this would be useful 🙂

ynjiun

Hi erik

Most of disparity error come from the mismatching of the correspondent pixels from left and right due to noise, repetitive texture or lack of texture, occlusion, etc.

If we already know certain disparity range smaller than the default search range for a given pixel, then we can narrow the search range thus less susceptible to noise, repetitive texture, etc. Make sense?

erik

Hi ynjiun ,
Thanks for elaborating. Stereo matching block (silicon) on RVC2 doesn't allow that, but you can reduce disparity search to 64 pixels, API here. You could also use disparity shift.

ynjiun

I understand the hardware does not support that. But can we support it by our DepthAI pipeline by doing following things?

default range (0, 96)
hardware compute the cost volume (H,W,96)
output disparity using D1,D2 map assuming 0<= d1 < d2 <= 96

Make sense?

erik

ynjiun Yes, thanks for elaborating. Please write feature request to depthai-core repo directly.