US 11,989,925 B2
Image matching apparatus
Toru Takahashi, Tokyo (JP); Rui Ishiyama, Tokyo (JP); Kengo Makino, Tokyo (JP); and Yuta Kudo, Tokyo (JP)
Assigned to NEC CORPORATION, Tokyo (JP)
Appl. No. 17/606,488
Filed by NEC Corporation, Tokyo (JP)
PCT Filed May 16, 2019, PCT No. PCT/JP2019/019532
§ 371(c)(1), (2) Date Oct. 26, 2021,
PCT Pub. No. WO2020/230320, PCT Pub. Date Nov. 19, 2020.
Prior Publication US 2022/0198777 A1, Jun. 23, 2022
Int. Cl. G06K 9/00 (2022.01); G06T 3/10 (2024.01); G06T 7/11 (2017.01); G06V 10/40 (2022.01); G06V 10/74 (2022.01); G06V 10/75 (2022.01)
CPC G06V 10/753 (2022.01) [G06T 3/10 (2024.01); G06T 7/11 (2017.01); G06V 10/40 (2022.01); G06V 10/761 (2022.01); G06T 2207/20021 (2013.01)] 20 Claims
OG exemplary drawing
 
11. An image matching method for matching a first image against a second image, the image matching method comprising:
acquiring a frequency feature of the first image and a frequency feature of the second image;
synthesizing the frequency feature of the first image and the frequency feature of the second image;
generating a quantized synthesized frequency feature in which a value of an element is represented by a binary value or a ternary value;
calculating a score indicating a degree to which the quantized synthesized frequency feature is a square wave having a single period; and
matching the first image against the second image based on the score.