A pedestrian starts to cross the street after the "Don't Walk" signal begins to flash. The pedestrian is in the middle of the street when your signal light changes to green. You should:

At a green light, you must give the right-of-way to any vehicle, bicyclist, or pedestrian in the intersection. If a pedestrian begins crossing the street after the traffic signal light starts flashing, wait until they have crossed the street before proceeding.
DMV Writen Test