Patent attributes
An image analysis apparatus rectifies a first image and a second image to generate a first rectified image and a second rectified image respectively. A first container door in the first rectified image and a second container door in the second rectified image have the same sizes and the same pixel coordinates. The image analysis apparatus divides the first rectified image into a plurality of first blocks and divides the second rectified image into a plurality of second blocks in a same manner. The image analysis apparatus calculates respective correlations between every first block and its corresponding second block. Each of the correlations includes a grayscale correlation and at least one color correlation. The image analysis apparatus determines whether the first container door and the second container door represent the same container door based on the correlations.
