1. A method of recognizing a touch gesture to be performed by an apparatus for recognizing a touch gesture, the method comprising: obtaining, by a processor included in the apparatus, a depth image in which a touch object and a background area are captured; detecting, by the processor, from the depth image, a touch input applied by the touch object to the background area in a touch detection area; and recognizing, by the processor, a touch gesture associated with the touch input by tracking a change in the touch input, wherein the background area is learned based on whether a touch event is present in a touch detection area of a learning depth image, wherein the touch event is determined to be present in the touch detection area of the learning depth image when a curvature of a background area satisfies a predetermined learning condition based on a change of the curvature, and wherein the curvature of the background area is determined to satisfy the predetermined learning condition when the change of the curvature is more than a curvature threshold.