1. A video surveillance method using an integrated circuit comprised in a portable terminal, the video surveillance method comprising: photographing, by an image sensor, a predetermined place and generating, by the integrated circuit, an image signal corresponding to the predetermined place; detecting a change in the image signal by calculating, by the integrated circuit, a difference between a current frame and a previous frame of the generated image signal; and generating alarm information, by the integrated circuit, corresponding to the detected change of a configured point of interest in the image signal in order to alarm a user, the point of interest being set by the user, wherein the detecting comprises generating a learned background image model, obtaining a background image from the learned background image model, and subtracting the background image from the generated image signal to extract changed pixels, and detecting the change in the image signal based on the changed pixels.