METHOD OF FAST IMAGE MATCHING

• US 20140212052A1
• Filed: 04/24/2013
• Published: 07/31/2014
• Est. Priority Date: 01/25/2013
• Status: Active Grant

• Current Assignee: Delta Electronics Incorporated
• Original Assignee: Delta Electronics Incorporated
• Inventors: WEI, Juang-Yu
• Granted Patent: US 9,165,215 B2
• Time in Patent Office: Days
• US Class Current: 382/216
• CPC Class Codes: G06V 10/754 involving a deformation of the sample pattern or of the reference pattern; Elastic matching

Abstract

Disclosed herein is a method of fast image matching that includes the steps as follows. A template image with a predetermined angular orientation is compared with template images in the range from 0 to 360 degrees to create an angle prediction table. Next, a testing image is acquired and compared with the template image with the predetermined angular orientation to record the similarity at each position, and a plurality of angles corresponding to the similarity is found from the angle prediction table. Afterwards, the template images of the plurality of angles are respectively compared with the testing image to obtain the highest similarity as a comparison result of the position.

Claims

1. A method of fast image matching, comprising:

(a) pre-comparing a template image with a predetermined angular orientation with the template images in the range from 0 to 360 degrees to create an angle prediction table;

(b) acquiring a testing image, comparing the testing image with the template image with the predetermined angular orientation to record the similarity at each position, and finding a plurality of angles corresponding to the similarity from the angle prediction table; and

(c) respectively comparing the template images with the plurality of angles with the testing image to obtain the highest similarity.

2. The method of fast image matching of claim 1, wherein the step (a) comprises:

comparing the template image with a predetermined angular orientation of 0 degree with the template images in the range from 0 to 360 degrees to record the comparison results;

determining if the comparison has been completed for each degree from 0 to 360; and

after the comparison has been completed, creating the angle prediction table according to the comparison results.

3. The method of fast image matching of claim 1, wherein the similarity of the testing image at a position is a numerical value, and in the angle prediction table the similarity of the template images with the plurality of angles is greater than the value;

in addition, the step (c) comprises;

acquiring the template images with the plurality of angles, comparing the template images with the plurality of angles with the testing image at that position, and outputting the highest similarity after the entire piece of the testing image is compared.

4. A method of fast image matching, comprising:

(a) comparing a template image with a predetermined angular orientation with the template images in the range from 0 to 360 degrees to create an angle prediction table;

(b) acquiring a testing image, and utilizing a circular projection method to find an area of an object corresponding to the template image in the testing image;

(c) comparing the area in the testing image with the template image with the predetermined angular orientation to record the similarity at each position, and finding a plurality of angles corresponding to the similarity from the angle prediction table; and

(d) respectively comparing the template images with the plurality of angles with the testing image to obtain the highest similarity.

5. The method of fast image matching of claim 4, wherein the step (a) comprises:

comparing the template image with a predetermined angular orientation of 0 degree with the template images in the range from 0 to 360 degrees to record the comparison results;

determining if the comparison has been completed for each degree from 0 to 360; and

after the comparison has been completed, creating the angle prediction table according to the comparison results.

6. The method of fast image matching of claim 4, wherein the similarity of the testing image at a position is a numerical value, and the similarity of the template images with the plurality of angles in the angle prediction table is greater than the value;

in addition, the step (d) comprises;

acquiring the template images with the plurality of angles, comparing the template images with the plurality of angles with the testing image at that position, and outputting the highest similarity after the area within the testing image is compared.

7. A method of fast image matching, comprising:

(a) pre-comparing a template image with a predetermined angular orientation with the template images in the range from 0 to 360 degrees to create an angle prediction table;

(b) acquiring a testing image, utilizing a hopscotch method to compare the testing image with the template image with the predetermined angular orientation to record the similarity at each hopscotch position, and finding a plurality of angles corresponding to the similarity from the angle prediction table; and

(c) respectively comparing the template images with the plurality of angles with the testing image to obtain the highest similarity.

8. The method of fast image matching of claim 7, wherein the step (a) comprises:

comparing the template image with a predetermined angular orientation of 0 degree with the template images in the range from 0 to 360 degrees to record the comparison results;

determining if the comparison has been completed for each degree from 0 to 360; and

after the comparison has been completed, creating the angle prediction table according to the comparison results.

9. The method of fast image matching of claim 7, wherein the similarity of the testing image at a hopscotch position is a numerical value, and in the angle prediction table the similarity of the template images with the plurality of angles is greater than the value;

in addition, the step (c) comprises;

acquiring the template images with the plurality of angles, comparing the template images with the plurality of angles with the testing image at that hopscotch position, and outputting the highest similarity after the entire piece of the testing image is compared.

10. The method of fast image matching of claim 7, wherein the step (b) comprises:

utilizing a circular projection method to find an area of an object corresponding to the template images in the testing image; and

utilizing the hopscotch method to compare the area in the testing image with the template image with the predetermined angular orientation to record the similarity at each hopscotch position.