| 摘要 |
PROBLEM TO BE SOLVED: To greatly reduce a calculation load of optical flow in a correlation computing method for allowing recognition of a moving body with a large relative speed to own vehicle. SOLUTION: As to each frame image, a plurality of calculation points are determined on each of radial search lines from an infinite point by means of a CPU, and a reference image area is set in a certain calculation point in a previous frame image before a time Δt, while a reference image area is set in a present frame image after a time Δt from the previous frame image. A cumulative sum of a luminance difference in each pixel inside the both reference image areas of the previous frame image and the present frame image is computed, and its minimum value is previously found to be stored in a memory. Subsequently, a cumulative sum of a luminance difference between a reference image area set in a calculation point in a frame image at a certain time and a reference image area set at a calculation point in the following frame image after a time Δt is computed, and if the cumulative sum exceeds the minimum value in the middle of computing, computing is stopped at that point. |
