US5418862A
Expired / Lapsed
US
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Method and apparatus for detecting artifact corners in two-dimensional images
Assignee: United Parcel Service of America Inc
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Filing: 1992-08-10
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Granted: 1995-05-23
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Expires: 2012-08-10
Abstract
Abstract A system for finding a corner of an artifact in a two-dimensional pixel image selects an original seed pixel and generates a reference vector using the original seed pixel. The system selects a next seed pixel using the original seed pixel and generates a current vector using the next seed pixel. The system compares the current vector to the reference vector and selects a corner based on that comparison. Also a system for finding a corner of a bar code symbol in a two-dimensional pixel image selects a sequence of seed pixels, having a first seed pixel and a plurality of successive seed pixels, where each successive seed pixel is selected in accordance with the previous seed pixel in the sequence. The system generates a reference vector in accordance with the first seed pixel and generates a plurality of successive vectors, each in accordance with a successive seed pixel. The system compares the reference vector to each of the successive vectors and selects a corner in accordance with the comparison.
Inventors
- 👤 Joe Zheng
- 👤 Mihael Klancnik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:16
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/1092; G06K7/14; G06K7/1404; G06K7/1439; G06K7/1443; G06K7/146; G06K7/1469; G06K7/1486; G06K7/1491
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
136 words
A method for detecting a corner of an artifact in a two-dimensional pixel image, comprising the steps of: (a) selecting an original seed pixel; (b) specifying the original seed pixel to be a current seed pixel; (c) selecting a next seed pixel in accordance with the current seed pixel; (d) specifying the next seed pixel to be the current seed pixel; (e) implementing steps (c) and (d) a plurality of times to select a plurality of seed pixels; (f) generating a reference vector in accordance with the original seed pixel and a seed pixel of the plurality of seed pixels; (g) generating a plurality of vectors in accordance with the plurality of seed pixels; (h) comparing each of the plurality of vectors to said reference vector; and (i) detecting a corner in accordance with said comparison.
Claim 2
Independent Claim
136 words
A method for detecting a corner of an artifact in a two-dimensional pixel image, comprising the steps of: (a) selecting an original seed pixel; (b) specifying the original seed pixel to be a current seed pixel; (c) selecting a next seed pixel in accordance with the current seed pixel; (d) specifying the next seed pixel to be the current seed pixel; (e) implementing steps (c) and (d) a plurality of times to select a plurality of seed pixels; (f) generating a reference vector in accordance with the original seed pixel and a seed pixel of the plurality of seed pixels; (g) generating a plurality of vectors in accordance with the plurality of seed pixels; (h) comparing each of the plurality of vectors to said reference vector; and (i) detecting a corner in accordance with said comparison.
Claim 3
Dependent Claim
45 words
The method of claim 1, wherein step (h) comprises the step of determining the magnitude of the vector difference between said reference vector and each of the plurality of vectors and wherein step (i) comprises the step of comparing said magnitude to a threshold magnitude.
Claim 4
Dependent Claim
42 words
The method of claim 1, wherein step (h) comprises the step of determining the phase angle between said reference vector and each of the plurality of vectors and wherein step (i) comprises the step of comparing said phase angle to a threshold.
Claim 5
Independent Claim
152 words
An apparatus for detecting a corner of an artifact in a two-dimensional pixel image, comprising: (a) means for selecting an original seed pixel; (b) means for specifying the original seed pixel to be a current seed pixel; (c) seed pixel selecting means for selecting a next seed pixel in accordance with the current seed pixel; (d) means for specifying the next seed pixel to be the current seed pixel; (e) means for selecting a plurality of seed pixels using means (c) and (d); (f) means for generating a reference vector in accordance with the original seed pixel and a seed pixel of the plurality of seed pixels; (g) means for generating a plurality of vectors in accordance with the plurality of seed pixels; (h) comparing means for comparing each of the plurality of vectors to said reference vector; and (i) corner detecting means for detecting a corner in accordance with said comparison.
Claim 6
Independent Claim
152 words
An apparatus for detecting a corner of an artifact in a two-dimensional pixel image, comprising: (a) means for selecting an original seed pixel; (b) means for specifying the original seed pixel to be a current seed pixel; (c) seed pixel selecting means for selecting a next seed pixel in accordance with the current seed pixel; (d) means for specifying the next seed pixel to be the current seed pixel; (e) means for selecting a plurality of seed pixels using means (c) and (d); (f) means for generating a reference vector in accordance with the original seed pixel and a seed pixel of the plurality of seed pixels; (g) means for generating a plurality of vectors in accordance with the plurality of seed pixels; (h) comparing means for comparing each of the plurality of vectors to said reference vector; and (i) corner detecting means for detecting a corner in accordance with said comparison.
Claim 7
Dependent Claim
40 words
The apparatus of claim 4, wherein said comparing means determines the magnitude of the vector difference between said reference vector and each of the plurality of vectors and wherein said corner detecting means compares said magnitude to a threshold magnitude.
Claim 8
Dependent Claim
37 words
The apparatus of claim 4, wherein said comparing means determines the phase angle between said reference vector and each of the plurality of vectors and wherein said corner detecting means compares said phase angle to a threshold.
Claim 9
Independent Claim
120 words
A method for detecting a corner of a bar code symbol in a two-dimensional pixel image, comprising the steps of: (a) selecting a sequence of seed pixels, said sequence comprising a first seed pixel and a plurality of successive seed pixels, each successive seed pixel being selected in accordance with the previous seed pixel in said sequence; (b) generating a reference vector in accordance with said first seed pixel and one of the plurality of successive seed pixels; (c) generating a plurality of successive vectors, each successive vector being in accordance with at least two of the successive seed pixels; (d) comparing said reference vector to each of said successive vectors; (e) detecting a corner in accordance with said comparison.
Claim 10
Independent Claim
120 words
A method for detecting a corner of a bar code symbol in a two-dimensional pixel image, comprising the steps of: (a) selecting a sequence of seed pixels, said sequence comprising a first seed pixel and a plurality of successive seed pixels, each successive seed pixel being selected in accordance with the previous seed pixel in said sequence; (b) generating a reference vector in accordance with said first seed pixel and one of the plurality of successive seed pixels; (c) generating a plurality of successive vectors, each successive vector being in accordance with at least two of the successive seed pixels; (d) comparing said reference vector to each of said successive vectors; (e) detecting a corner in accordance with said comparison.
Claim 11
Dependent Claim
44 words
The method of claim 7, wherein step (d) comprises the step of determining the magnitude of the vector difference between said reference vector and each of said successive vectors and wherein step (e) comprises the step of comparing said magnitude to a threshold magnitude.
Claim 12
Dependent Claim
40 words
The method of claim 7, wherein step (d) comprises the step of determining the phase angle between said reference vector and each of said successive vectors and wherein step (e) comprises the step of comparing said magnitude to a threshold.
Claim 13
Independent Claim
133 words
An apparatus for detecting a corner of a bar code symbol in a two-dimensional pixel image, comprising: (a) seed pixel selecting means for selecting a sequence of seed pixels, said sequence comprising a first seed pixel and a plurality of successive seed pixels, each successive seed pixel being selected in accordance with the previous seed pixel in said sequence; (b) means for generating a reference vector in accordance with said first seed pixel and one of the plurality of successive seed pixels; (c) means for generating a plurality of successive vectors, each successive vector being in accordance with at least two of said successive seed pixels; (d) comparing means for comparing said reference vector to each of said successive vectors; (e) corner detecting means for detecting a corner in accordance with said comparison.
Claim 14
Independent Claim
133 words
An apparatus for detecting a corner of a bar code symbol in a two-dimensional pixel image, comprising: (a) seed pixel selecting means for selecting a sequence of seed pixels, said sequence comprising a first seed pixel and a plurality of successive seed pixels, each successive seed pixel being selected in accordance with the previous seed pixel in said sequence; (b) means for generating a reference vector in accordance with said first seed pixel and one of the plurality of successive seed pixels; (c) means for generating a plurality of successive vectors, each successive vector being in accordance with at least two of said successive seed pixels; (d) comparing means for comparing said reference vector to each of said successive vectors; (e) corner detecting means for detecting a corner in accordance with said comparison.
Claim 15
Dependent Claim
39 words
The apparatus of claim 10, wherein said comparing means determines the magnitude of the vector difference between said reference vector and each of said successive vectors and wherein said corner selecting means compares said magnitude to a threshold magnitude.
Claim 16
Dependent Claim
35 words
The apparatus of claim 10, wherein said comparing means determines the phase angle between said reference vector and each of said successive vectors and wherein said corner selecting means compares said magnitude to a threshold.
References Cited (Backward Citations)
US4847911A
Cited
US5045677A
Cited
US5155344A
Cited
US5036182A
Cited
US4988852A
Cited
US4873426A
Cited
US4973829A
Cited
US4948955A
Cited
US5007098A
Cited
US4958064A
Cited
US5073954A
Cited
US5081689A
Cited
EP0449634A2
Cited
EP0450878A1
Cited
EP0449645A1
Cited
US5155343A
Cited
US4992650A
Cited
US5050222A
Cited
US5120940A
Cited
US5173946A
Cited
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