solidity concept in labeled components

can anyone tell me the solidity concept in simple words?

Answer 1

[Image Analyst]

Solidity is area fraction of the region as compared to its convex hull. The convex hull is what you'd get if you wrapped a rubber band around your region. So solidity is what fraction of the actual area your region is. For any convex object it's 1. An asterisk might have a solidity of around 0.5, while a thin "L" shape (or T or E, etc.)would have a very low solidity. The more bays, nooks, and crannies it has, the lower the solidity.

[Nurzamal Islam]

can you please explain the solidity taking any image as an example?

[Image Analyst]

I don't know how to explain it any better than what I already did above. It's the ratio of the actual blob area to the convex hull (rubber band) area. What is not understandable about that?

Answer 2

[Sean de Wolski]

Solidity: Area / Convex Hull Area

A rectangle will have a solidity of 1 because it is convex and thus its area is the convex area. A pacman will have a solidity of a little more than 0.75 since its area is about 3/4 of the almost circle that is its convex hull.

http://www.pacmangame.net/pacman-chart.gif

Note the convex hull would not include the circle segment between the top and bottom of its mouth