Which of the following are true, and which are false? 

a. Finding corresponding points in stereo images is the easiest phase of the stereo depthfinding process. 

b. Shape-from-texture can be done by projecting a grid of light-stripes onto the scene.

c. Lines with equal lengths in the scene always project to equal lengths in the image. 

d. Straight lines in the image necessarily correspond to straight lines in the scene.