[Shape from contours] Convex vs Visual Hull

[Shape from contours] Convex vs Visual Hull

by Adam Narozniak -
Number of replies: 1

Hello,

1. I don't understand how we get from the convex hull to the visual hull [slide 19 from the Shape from Contrours]. (what operations need to be taken to go from one state to the other and why). Also, I found that the visuall hull is directly obtained as the intersection of the silhouettes' cones on the Wikipedia article. [https://en.wikipedia.org/wiki/Visual_hull]

Could you please clarify that? Thanks in advance!

In reply to Adam Narozniak

Re: [Shape from contours] Convex vs Visual Hull

by Benoît Guillard -
Hello,
You do not "go" from convex hull to visual hull. As explained in the video (https://tube.switch.ch/videos/6WW7NAct33 at 23:00), this slide was just recapitulating the different levels of details: the bounding box of the object contains the convex hull, which contains the visual hull, which contains the object.
As explained on slide 17, you indeed take the intersections of the silhouettes' cones to get the visual hull.

Best,
Benoit