Hash-based image identification
US7761466B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 30, 2007 |
| Grant date | Jul 20, 2010 |
| Priority date | — |
| Expiry date | Apr 22, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/40
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Provided are, among other things, systems, methods and techniques for identifying target images in the following manner. Keypoints at different locations within a sample image and descriptor vectors for the keypoints are obtained, the descriptor vectors describing local image information around the keypoints. Features are generated based on hashes of data vectors that include at least one of the descriptor vectors, and an image-feature database is searched for the features. Target images are retrieved and provided based on the number of the features for which corresponding features exist in individual database images whose features are represented in the image-feature database. The foregoing hashes are performed using a hash function for which a probability that the hash of an arbitrary first vector corresponds to the hash of an arbitrary second vector is a function of an angle between the first vector and the second vector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.