1. A projection control method for a projector connected to an image capturing device, the method comprising: predetermining hand gestures, assigning an operation function of an input device to each of the predetermined hand gestures; receiving an image of a speaker captured by the image capturing device when an electronic file is projected onto a screen by the projector; identifying whether a hand gesture of the speaker matches one of the predetermined hand gestures; and upon the condition that the hand gesture matches one of the predetermined hand gestures, executing a corresponding assigned operation function.