Method and system for comparing images

摘要

A method for comparing a first image with a second image. The method identifies first keypoints in the first image and second keypoints in the second image and associates each first keypoint with a corresponding second keypoint to form a corresponding keypoint match. For each pair of first keypoints, the method further calculates the distance therebetween for obtaining a corresponding first length. Similarly, for each pair of second keypoints, the method calculates the distance therebetween for obtaining a corresponding second length. The method further calculates a plurality of distance ratios; each distance ratio is based on a length ratio between a selected one between a first length and a second length and a corresponding selected one between a second length and a first length, respectively.

主权项

1. A method for comparing a first image with a second image, comprising:
identifying first keypoints in the first image and second keypoints in the second image by a computer: associating each first keypoint with a corresponding second keypoint to form a corresponding keypoint match; for each pair of first keypoints, calculating a distance therebetween for obtaining a corresponding first length; for each pair of second keypoints, calculating a distance therebetween for obtaining a corresponding second length; calculating a first plurality of distance ratios, each distance ratio being based on a length ratio between one of the first lengths and corresponding one of the second lengths; calculating a statistical distribution of the first plurality of distance ratios; generating a model function expressing a statistical distribution of a second plurality of distance ratios corresponding to a random selection of keypoints in the first and second images; comparing the statistical distribution of the first plurality of distance ratios with the model function; and assessing whether the first image contains a view of an object depicted in the second image based on the comparison.