US4487476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of multivariant intraclass pattern recognition
Assignee: United States Department of the Air Force
•
Filing: 1981-04-28
•
Granted: 1984-12-11
•
Expires: 2001-04-28
Abstract
Abstract A method of recognizing different perspective views or images (i.e., multivariant views) of the same object (i.e., intraclass patterns). Each intraclass pattern, or different representation of the same object, is described as an orthonormal basis function expansion, and a single averaged matched spatial filter is produced from a weighted linear combination of these functions. The method eliminates the multiple matched spatial filters, and the extensive postprocessing of the matrix output from a multichannel correlator, which are used in the prior art.
Inventors
- 👤 Charles F. Hester
- 👤 David P. Casasent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:29
CPC Classifications
G; G06; G06V; G06V10/00; G06V10/88; G06V10/92; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
69 words
A method of pattern recognition comprising the steps of: inputting a transform F of an input object f into a correlator: inputting said transform F into a matched spatial filter having a transmittance proportional to H* wherein said H* is a conjugate transform of a multiclass reference function defined by h, said matched filter outputting a transform FH*, and forming a transform correlation product f * h of FH*.
Claim 2
Independent Claim
69 words
A method of pattern recognition comprising the steps of: inputting a transform F of an input object f into a correlator: inputting said transform F into a matched spatial filter having a transmittance proportional to H* wherein said H* is a conjugate transform of a multiclass reference function defined by h, said matched filter outputting a transform FH*, and forming a transform correlation product f * h of FH*.
Claim 3
Independent Claim
130 words
A method of constructing a single matched spatial filter (MSF) having thereon a transformer of a multiclass reference function h, said method comprising the steps of: calculating an average filter equation of said multiclass reference function h; constructing an average filter h given said average filter equation; placing said average filter h at a first position in a plane correlator; forming a transform H of said multiclass reference function h by a lens in said plane correlator, placing a recording medium in a second position at a focus of said lens, and recording on said medium said transform H coherently interferring with a plane wave reference beam incident at a selected angle, said recording medium thereafter being a MSF H* having a transmittance that is proportional to said transform H*.
Claim 4
Independent Claim
130 words
A method of constructing a single matched spatial filter (MSF) having thereon a transformer of a multiclass reference function h, said method comprising the steps of: calculating an average filter equation of said multiclass reference function h; constructing an average filter h given said average filter equation; placing said average filter h at a first position in a plane correlator; forming a transform H of said multiclass reference function h by a lens in said plane correlator, placing a recording medium in a second position at a focus of said lens, and recording on said medium said transform H coherently interferring with a plane wave reference beam incident at a selected angle, said recording medium thereafter being a MSF H* having a transmittance that is proportional to said transform H*.
Claim 5
Dependent Claim
24 words
A method of constructing a single MSF as defined in claim 2 wherein said constructing of an average filter uses the Vander Lugt method.
References Cited (Backward Citations)
US3435244A
Cited
US3814943A
Cited
US3814520A
Cited
US3779492A
Cited
US3905019A
Cited
US3879131A
Cited
US3993976A
Cited
US4073010A
Cited
US4084255A
Cited
US4174179A
Cited
US4174885A
Cited
US4338030A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |