1. A method for detecting moving objects, comprising: identifying a plurality of feature points based on a plurality of video frames; selecting from the plurality of feature points first and second groups of feature points based on correlations between the plurality of feature points; identifying in at least one video frame two segments based on the first and the second groups of feature points, respectively, as detected moving objects, where a correlation between two feature points comprises a distance component and a movement difference component, where the distance component is related to a distance between the two feature points, and the movement difference component is related to a difference between corresponding movements of the two feature points; determining that the first and the second groups have a common feature point; identifying a first base point from the first group that represents the feature points of the first group; identifying a second base point from the second group that represents the feature points of the second group; and classifying the common feature point into the first group in response to determining that the first base point of the first group has a larger correlation with the common feature point than the second base point of the second group.