Comparing device

摘要

When comparing a reference image and a registered image, a reference image is defined as a high-resolution image of the highest resolution and a first low-resolution image is generated on a lower level, and a second low-resolution image is generated on a lower level. Registered images are read one-at-a-time, feature regions are set in the hierarchical images of the registered images, and corresponding regions are found in the reference image through hierarchical searching from the low-resolution image towards the high-resolution image. An evaluation is made as to whether to select the registered image that has been read out, based on a similarity between the low-resolution hierarchical image, for example, a feature region of the hierarchical image of the registered image, and the corresponding region of the hierarchical image of the reference image, to narrow down the registered images to be compared to the reference image.

主权项

1. A comparing device for comparing a reference image and a registered image, comprising:
a hierarchical image generator generating a plurality of hierarchical images of different resolutions, with the raw image as a high-resolution image of the highest resolution, with this high-resolution image as the highest level; a registered image storage storing a plurality of registered images of the same resolution as the reference image; a registered image reader reading out, one-at-a-time, registered images stored in the registered image storage; a feature region setting device setting a feature region, determined in advance, for either a hierarchical image of the reference image, generated by the hierarchical image generator, or a hierarchical image of the reference image corresponding to a hierarchical image of the reference image of a registered image read out by the registered image reader; a corresponding region searching device searching, in the other hierarchical image, a corresponding region that corresponds to the feature region of the hierarchical image for which the feature region is set by the feature region setting device; and a first recorded image candidate selector selecting a registered image candidate for comparing a registered image, read out by the registered image reader, to a reference image based on a similarity between a feature region that is established for one hierarchical image by the feature region setting device and a corresponding region, found in the other hierarchical image, by a corresponding region finding device.