Patent ID: 8620030

Claim:
An apparatus comprising: a storage unit configured to store first signals and second signals extracted from a tracking area in first image data; and a detection unit configured to extract an area having signals in which are high correlation with the first signals from second image data and to update the tracking area with the extracted area; wherein when the detection unit cannot extract an area having signals in which are high correlation with the first signals from the second image data, the detection unit determines whether an area, having signals in which are high correlation with the second signals, can be extracted from the third image data, and if the area cannot be extracted, the detection unit resets the tracking area, and if the area can be extracted, the detection unit updates the tracking area with the extracted area, wherein, when the tracking area is updated, the storage unit updates the first signals with the first signals extracted from the updated tracking area, wherein, the detection unit extracts an area having signals in which are high correlation with the updated first signals from fourth image data, and, wherein the detection unit determines whether an area, having signals in which are high correlation with the second signals extracted from the first image, can be extracted from the fifth image data when the detection unit cannot extract the area having signals in which are high correlation with the updated first signals from fourth image data.