US3887764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Feature classification in image analysis
Assignee: Image Analysing Computers Ltd
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Filing: 1972-05-05
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Granted: 1975-06-03
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Expires: 1992-05-05
Abstract
Abstract Methods and apparatus employing fixed raster scanning for classifying steels according to the non-metallic inclusion content apparent in a polished surface of a sample thereof. The method allows for individual regions of the surface to be analysed and classified and an overall classification to be made in accordance with the predominant classification of a number of regions making-up the surface. Signals relating to sulphide and oxide inclusion content are discriminated by virtue of amplitude difference. Areas of each are determined in known manner by accumulating detected signal pulses during a single frame scan. Signals relating to different types of oxide inclusions are distinguished by making measurements on the detected signal pulses relating to the oxide inclusions.
Inventors
- 👤 John Michael Gibbons
- 👤 William Ralph Knowles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:36
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/10; G01N15/14; G01N15/1429; G01N15/1433
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
202 words
A method of classifying a region of a polished steel surface containing non-metallic inclusions which appear darker than the remainder of the steel surface, comprising the steps of scanning an image of the region in a series of parallel lines forming a raster, generating an amplitude varying video signal from the scanning, in which the amplitude has a first value corresponding to the steel, a second value corresponding to sulphide inclusions and a third value corresponding to oxide inclusions, comparing the video signal with a first reference voltage between the said first and second values and with a second reference voltage between the said second and third values, generating a first detected signal of pulses generated whenever the video signal amplitude has a value between the first and second reference voltages and a second detected signal of pulses generated whenever the video signal amplitude has a value below the second reference voltage, performing measurements on the pulses forming the second detected signal arising from scanning the whole region to produce at least first and second output signals, comparing the relative magnitudes of said output signals and generating a classifying signal for the region in response to the comparison of the output signals.
Claim 2
Independent Claim
202 words
A method of classifying a region of a polished steel surface containing non-metallic inclusions which appear darker than the remainder of the steel surface, comprising the steps of scanning an image of the region in a series of parallel lines forming a raster, generating an amplitude varying video signal from the scanning, in which the amplitude has a first value corresponding to the steel, a second value corresponding to sulphide inclusions and a third value corresponding to oxide inclusions, comparing the video signal with a first reference voltage between the said first and second values and with a second reference voltage between the said second and third values, generating a first detected signal of pulses generated whenever the video signal amplitude has a value between the first and second reference voltages and a second detected signal of pulses generated whenever the video signal amplitude has a value below the second reference voltage, performing measurements on the pulses forming the second detected signal arising from scanning the whole region to produce at least first and second output signals, comparing the relative magnitudes of said output signals and generating a classifying signal for the region in response to the comparison of the output signals.
Claim 3
Independent Claim
189 words
A METHOD OF CLASSIFYING A REGION OF A POLISHED STEEL SURFACE CONTAINING NON-METALLIC INCLUSIONS WHICH APPEAR DARKER THAN THE REMAINDER OF THE STEEL SURFACE, COMPRISING THE STEPS OF SCANNING AN IMAGE OF THE REGION IN A SERIES OF PARALLEL LINES FORMING A RASTER, GENERATING AN AMPLITUDE VARYING VIDEO SIGNAL FROM THE SCANNING, IN WHICH THE AMPLITUDE HAS A FIRST VALUE CORRESPONDING TO THE STEEL, A SECOND VALUE CORRESPONDING TO SULPHIDE INCLUSIONS AND A THIRD VALUE CORRESPONDING TO OXIDE INCLUSIONS, COMPARING THE VIDEO SIGNAL WITH A FIRST REFERENCE VOLTAGE BETWEEN THE SAID FIRST AND SECOND VALUES AND WITH A SECOND REFERENCE VOLTAGE BETWEEN THE SAID SECOND AND THIRD VALUES, GENERATING A FIRST DETECTED SIGNAL OF PLUSES GENERATED WHENEVER THE VIDEO SIGNAL AMPLITUDE HAS A VALUE BETWEEN THE FIRST AND SECOND REFERENCE VOLTAGES AND A SECOND DETECTED SIGNAL OF PLUSES GENERATED WHENEVER THE VIDEO SIGNAL AMPLITUDE HAS A VALUE BELOW THE SECOND REFERENCE VOLTAGE, PERFORMING MEASUREMENTS ON THE PLUSES FORMING THE SECOND DETECTED SIGNAL ARISING FROM SCANNING THE WHOLE REGION TO PRODUCE AT LEAST FIRST AND SECOND OUTPUT SIGNALS, COMPARING THE RELATIVE MAGNITUDES OF SAID OUTPUT SIGNALS AND GENERATING A CLASSIFYING
Claim 4
Independent Claim
189 words
A METHOD OF CLASSIFYING A REGION OF A POLISHED STEEL SURFACE CONTAINING NON-METALLIC INCLUSIONS WHICH APPEAR DARKER THAN THE REMAINDER OF THE STEEL SURFACE, COMPRISING THE STEPS OF SCANNING AN IMAGE OF THE REGION IN A SERIES OF PARALLEL LINES FORMING A RASTER, GENERATING AN AMPLITUDE VARYING VIDEO SIGNAL FROM THE SCANNING, IN WHICH THE AMPLITUDE HAS A FIRST VALUE CORRESPONDING TO THE STEEL, A SECOND VALUE CORRESPONDING TO SULPHIDE INCLUSIONS AND A THIRD VALUE CORRESPONDING TO OXIDE INCLUSIONS, COMPARING THE VIDEO SIGNAL WITH A FIRST REFERENCE VOLTAGE BETWEEN THE SAID FIRST AND SECOND VALUES AND WITH A SECOND REFERENCE VOLTAGE BETWEEN THE SAID SECOND AND THIRD VALUES, GENERATING A FIRST DETECTED SIGNAL OF PLUSES GENERATED WHENEVER THE VIDEO SIGNAL AMPLITUDE HAS A VALUE BETWEEN THE FIRST AND SECOND REFERENCE VOLTAGES AND A SECOND DETECTED SIGNAL OF PLUSES GENERATED WHENEVER THE VIDEO SIGNAL AMPLITUDE HAS A VALUE BELOW THE SECOND REFERENCE VOLTAGE, PERFORMING MEASUREMENTS ON THE PLUSES FORMING THE SECOND DETECTED SIGNAL ARISING FROM SCANNING THE WHOLE REGION TO PRODUCE AT LEAST FIRST AND SECOND OUTPUT SIGNALS, COMPARING THE RELATIVE MAGNITUDES OF SAID OUTPUT SIGNALS AND GENERATING A CLASSIFYING
Claim 5
Dependent Claim
32 words
The method as set forth in claim 1 comprising the steps of accumulating separately the pulses of each detected signal to form two output signals during each scan of the said region.
Claim 6
Dependent Claim
47 words
The method as set forth in claim 2 comprising the steps of dividing the one output signal by the other to form a quotient signal, generating a reference signal and comparing the quotient signal with the reference signal to effect comparison of the said two output signals.
Claim 7
Dependent Claim
93 words
The method as set forth in claim 1 comprising the steps of generating from the second detected signal pulses a first output signal corresponding to the total of the horizontally projected lengths of the detected oxide inclusions in the region and a second output signal corresponding to the total of the vertically projected lengths of the detected oxide inclusions in the region, comparing the magnitudes of the first and second output signals and generating a type-C classifying signal if the second output signal is greater than a multiple of the first output signal.
Claim 8
Dependent Claim
18 words
The method as set forth in claim 4 wherein the preffered value for the first multiple is 1.7.
Claim 9
Dependent Claim
121 words
The method as set forth in claim 4 further comprising the steps of generating from the second detected signal pulses a first count pulse for each detected oxide inclusion, associating the detected signal pulses arising from inclusions separated by less than given distances (measured parallel and perpendicular to the line scan direction) from other inclusions and generating for each group of associated detected signal pulses a second count pulse, counting the first and second count pulses to form third and fourth output signals respectively, comparing the magnitude of the fourth output signal with that of the third output signal and generating a type-B classifying signal if the third signal magnitude is greater than a second multiple of the fourth signal magnitude.
Claim 10
Dependent Claim
18 words
The method as set forth in claim 6 wherein the preferred value for the second multiple is 2.0.
Claim 11
Dependent Claim
36 words
The method as set forth in claim 6 further comprising the step of generating a type-D classifying signal if the comparisons effected on the first and second and third and fourth output signals are both negative.
Claim 12
Dependent Claim
51 words
The method as set forth in claim 4 whErein the second output signal is generated by selecting from the intersect pulses arising from scanning each inclusion the longest duration pulse therefrom and accumulating all said longest duration pulses during a scan of the region to form the said second output signal.
Claim 13
Dependent Claim
152 words
The method as set forth in claim 1 comprising the steps of generating a length signal corresponding to the length dimension of each inclusion from the intersect pulses relating thereto, applying first size discrimination to each length signal and generating a count pulse for each inclusion for which the first length signal is greater than the first size, applying a second size discrimination to the length signals and generating a count pulse for each inclusion for which the first length signal is greater than the second size, (larger than the first size), counting the two sets of count pulses to produce first and second count signals (constituting said first and second output signals respectively), comparing the two count signals and generating a type-C classifying signal if the count signal due to the first size discrimination is not greater than a given multiple of the count signal due to the second size discrimination.
Claim 14
Dependent Claim
30 words
The method as set forth in claim 10 wherein preferred ranges of the first and second sizes are 2 to 30 Mu m and 8 to 120 Mu m respectively.
Claim 15
Dependent Claim
44 words
The method as set forth in claim 10 wherein the comparison is effected by dividing the second count signal by the first count signal to form a quotient signal generating a reference value signal and comparing the quotient signal with the reference value signal.
Claim 16
Dependent Claim
22 words
The method as set forth in claim 12 wherein a preferred range of values for the reference value is 0.1 - 0.8.
Claim 17
Dependent Claim
14 words
The method as set forth in claim 12 wherein the reference value is 0.5.
Claim 18
Dependent Claim
113 words
The method as set forth in claim 1 comprising the steps of computing from the second detected signal pulses a signal corresponding to the total projected length (in one direction) of the detected oxide inclusions, computing therefrom a signal corresponding to the arithmetic square of the total projected length to obtain a first area value signal, to form the first output signal, computing from the second detected signal pulses a signal corresponding to the actual total area of the detected oxide inclusions to obtain a second area value signal to form the second output signal, comparing the two area value signals and generating a type-C classifying signal if a comparison criterion is satisfied.
Claim 19
Dependent Claim
76 words
The method as set forth in claim 1 comprising the steps of computing from the second detected signal pulses a signal corresponding to the total of all perimeters of detected oxide inclusions to obtain a total perimeter first output signal, generating a total area (second output) signal by accumulating the second detected signal pulses, comparing the total perimeter signal with the total area signal and generating a type-C classifying signal if a comparison criterion is satisfied.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |