# VOA feature reference

Source: https://forum.modalai.com/topic/260/voa-feature-reference
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2021-06-01 10:05:25 UTC by shlee853
Replies: 2 · Views: 640

## shlee853 · 2021-06-01 10:05:25 UTC

Hi dev,

I'm looking for references of VOA feature using stereo vision.

I also investigated how to calculate distance from stereo vision in voa_manager.c.

But, I didn't find how to get point cloud and R_stereo_to_level/T_stereo_wrt_level.

I may not understand this way from conventional computer vision to find disparity using stereo camera.

Could you please let me know references doc or website applied this vision processing?

Thanks,

## Reply by Chad Sweet (ModalAI staff) · 2021-06-02 04:05:45 UTC

You are referring to depth from stereo, you can see a reference of that here:  https://gitlab.com/voxl-public/modal-pipe-architecture/voxl-dfs-server/-/tree/dev and how to use that point cloud for VOA here: https://gitlab.com/voxl-public/modal-pipe-architecture/voxl-vision-px4/-/blob/dev/src/voa_manager.c

## Reply by shlee853 · 2021-06-04 21:25:16 UTC (in reply to Chad Sweet)

@Chad-Sweet voxl-dfs-server is for voxl-vision-px4 ver 0.8.1.

version 0.6.8 is not used voxl-dfs-server.

could you please let me know based of voxl-vision-px4 ver 0.6.8?

Thanks,