Provided is an image processing apparatus for extracting a three-dimensional feature point from a depth image. The cylinders meet to form a common combustion chamber. Movement of the limb supports closer together and further apart may cause the limbs to pivot to and from positions. A method of making the acoustical panel includes making a slurry comprising calcium sulfate hemihydrate, polyethylene glycol, water and at least one of the group consisting of a lightweight aggregate, fibers and combinations thereof. The indication element is triggered when the first element moves to overlap the second element. Also described is a heat transfer system comprising the heat transfer fluid.