Abstract
In recent years, adoption of a rear monitor camera is increasing for a blind spot monitor when reversing. If approaching vehicles can be recognized using this camera, a rear obstacle warning system can be realized at low cost. However, this camera is fitted with a wide-angle lens, thus it is difficult to recognize the approaching vehicles due to the image quality. Selected fundamental algorithms and newly created ones were used for the recognition. As a result, robust recognition performance under various environments is obtained. For the covering abstract see ITRD E134653.