US6400848B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for modifying the perspective of a digital image
Assignee: Apple Inc
•
Filing: 1999-03-30
•
Granted: 2002-06-04
•
Expires: 2019-03-30
Abstract
Abstract A method for modifying an apparent perspective of a digital image representing a perspective projection of a scene, the method comprises the steps of locating a line in the digital image; computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and resampling the digital image based on the correction term for creating a processed image.
Inventors
- 👤 Andrew C. Gallagher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:21
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/80
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
77 words
A method for modifying an apparent perspective of a digital image representing a perspective projection of a scene, the method comprising the steps of: (a) locating a line in the digital image; (b) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) resampling the digital image based on the correction term for creating a processed image.
Claim 2
Independent Claim
77 words
A method for modifying an apparent perspective of a digital image representing a perspective projection of a scene, the method comprising the steps of: (a) locating a line in the digital image; (b) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) resampling the digital image based on the correction term for creating a processed image.
Claim 3
Dependent Claim
37 words
The method of claim 1 , wherein step (b) further comprises: (b1) calculating the correction term such that when the digital image is resampled in step (c) the located line is substantially vertical in the processed image.
Claim 4
Dependent Claim
19 words
The method of claim 2 , wherein step (b) further comprises computing a vanishing point for the located line.
Claim 5
Dependent Claim
59 words
The method as in claim 3 , wherein step (b) further comprises computing the correction term based on the following formula: cf=z/(z+rows/2) where cf is the correction term, z is the distance in pixels between the vanishing point of the located line to the image center, and rows is the number of rows contained in the image being processed.
Claim 6
Dependent Claim
71 words
The method as in claim 3 , wherein step (b) further comprises computing the correction term based on the following formula: cf=|r|/(|r|−0.5 rows*cos θ) where cf is the correction term, r is the shortest distance in pixels between the located line to the image center, θ is the angle of the located line with respect to the horizontal, and rows is the number of rows contained in the image being processed.
Claim 7
Dependent Claim
60 words
The method as in claim 1 , wherein step (a) further comprises the steps of: (a1) generating an edge image from the digital image (a2) computing a Hough transform of the edge image; and (a3) detecting peaks of a Hough accumulator; and (a4) identifying the peaks of the Hough accumulator which correspond to a located line in the digital image.
Claim 8
Dependent Claim
51 words
The method as in claim 6 , wherein step (a1) further comprises the steps of: (a11) blurring the digital image with a digital filter; (a12) calculating a gradient of the blurred digital image; and (a13) applying a threshold to the gradient of the blurred digital image for producing the edge image.
Claim 9
Dependent Claim
86 words
The method as in claim 6 , wherein step (a3) further comprises the steps: (a31) filtering the Hough accumulator with a matched filter; (a32) generating a difference accumulator with the filtered Hough accumulator and the Hough accumulator; (a32) applying a threshold to the difference accumulator creating a peak image; (a33) identifying local maximum values of the peak image; and (a34) if the local maximum is nonzero and equal to the value of the peak image at any particular location, identifying that location as a peak value.
Claim 10
Dependent Claim
28 words
The method as in claim 6 , wherein step (a4) further comprises the steps of: (a41) identifying those peak values of step (a3) that correspond to located lines.
Claim 11
Dependent Claim
65 words
The method as in claim 1 , wherein step (c) further comprises the steps of: (c1) re-sampling a row of pixels of the digital image such that the rate of interpolation is dependent on the correction term, and a position of the row of pixels with respect to the central row of pixels; and (c2) repeating step (c1) for all the other rows of pixels.
Claim 12
Independent Claim
75 words
A method for modifying a perspective of a digital image, the method comprising the steps of. (a) subsampling the digital image; (b) locating a line in the sub-sampled digital image; (c) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (d) resampling the digital image based on the correction term for creating a processed image.
Claim 13
Independent Claim
75 words
A method for modifying a perspective of a digital image, the method comprising the steps of. (a) subsampling the digital image; (b) locating a line in the sub-sampled digital image; (c) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (d) resampling the digital image based on the correction term for creating a processed image.
Claim 14
Dependent Claim
90 words
A computer program product for modifying an apparent perspective of a digital image representing a perspective projection of a scene, comprising: a computer readable storage medium having a computer program stored thereon for performing the steps of: (a) locating a line in the digital image; (b) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) resampling the digital image based on the correction term for creating a processed image.
Claim 15
Dependent Claim
90 words
A computer program product for modifying an apparent perspective of a digital image representing a perspective projection of a scene, comprising: a computer readable storage medium having a computer program stored thereon for performing the steps of: (a) locating a line in the digital image; (b) computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) resampling the digital image based on the correction term for creating a processed image.
Claim 16
Dependent Claim
39 words
The computer program product of claim 12 , wherein step (b) further comprises: (b1) calculating the correction term such that when the digital image is resampled in step (c) the located line is substantially vertical in the processed image.
Claim 17
Dependent Claim
21 words
The computer program product of claim 13 , wherein step (b) further comprises computing a vanishing point for the located line.
Claim 18
Dependent Claim
61 words
The computer program product as in claim 14 , wherein step (b) further comprises computing the correction term based on the following formula: cf=z/(z+rows/2) where cf is the correction term, z is the distance in pixels between the vanishing point of the located line to the image center, and rows is the number of rows contained in the image being processed.
Claim 19
Dependent Claim
73 words
The computer program product as in claim 14 , wherein step (b) further comprises computing the correction term based on the following formula: cf=|r|/(|r|−0.5 rows*cos θ) where cf is the correction term, r is the shortest distance in pixels between the located line to the image center, θ is the angle of the located line with respect to the horizontal, and rows is the number of rows contained in the image being processed.
Claim 20
Dependent Claim
59 words
The computer program product as in claim 12 , wherein step (a) further comprises: (a1) generating an edge image from the digital image (a2) computing a Hough transform of the edge image; and (a3) detecting peaks of a Hough accumulator; and (a4) identifying the peaks of the Hough accumulator which correspond to a located line in the digital image.
Claim 21
Dependent Claim
53 words
The computer program product as in claim 17 , wherein step (a1) further comprises the steps of: (a11) blurring the digital image with a digital filter; (a12) calculating a gradient of the blurred digital image; and (a13) applying a threshold to the gradient of the blurred digital image for producing the edge image.
Claim 22
Dependent Claim
88 words
The computer program product as in claim 17 , wherein step (a3) further comprises the steps: (a31) filtering the Hough accumulator with a matched filter; (a32) generating a difference accumulator with the filtered Hough accumulator and the Hough accumulator; (a32) applying a threshold to the difference accumulator creating a peak image; (a33) identifying local maximum values of the peak image; and (a34) if the local maximum is nonzero and equal to the value of the peak image at any particular location, identifying that location as a peak value.
Claim 23
Dependent Claim
30 words
The computer program product as in claim 17 , wherein step (a4) further comprises the steps of: (a41) identifying those peak values of step (a3) that correspond to located lines.
Claim 24
Dependent Claim
70 words
The computer program product as in claim 13 , wherein the re-sampling means further comprises: (c1) means for re-sampling a row of pixels of the digital image such that the rate of interpolation is dependent on the correction term, and a position of the row of pixels with respect to the central row of pixels; and (c2) means for repeating the means (c1) for all the other rows of pixels.
Claim 25
Independent Claim
80 words
A system for modifying an apparent perspective of a digital image representing a perspective projection of a scene, the system comprising: (a) means for locating a line in the digital image; (b) means for computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) means for resampling the digital image based on the correction term for creating a processed image.
Claim 26
Independent Claim
80 words
A system for modifying an apparent perspective of a digital image representing a perspective projection of a scene, the system comprising: (a) means for locating a line in the digital image; (b) means for computing a correction term based on parameters of the located line which said correction term is related to the perspective of the digital image relative to the scene; and (c) means for resampling the digital image based on the correction term for creating a processed image.
Claim 27
Dependent Claim
41 words
The system of claim 22 , wherein the computing means further comprises: (b1) the calculating means includes the correction term such that when the digital image is resampled in step (c) the located line is substantially vertical in the processed image.
Claim 28
Dependent Claim
22 words
The system of claim 23 , wherein the calculating means further comprises means for computing a vanishing point for the located line.
Claim 29
Dependent Claim
62 words
The system as in claim 24 , wherein the calculating means further comprises means for computing the correction term based on the following formula: cf=z/(z+rows/2) where cf is the correction term, z is the distance in pixels between the vanishing point of the located line to the image center, and rows is the number of rows contained in the image being processed.
Claim 30
Dependent Claim
72 words
The system as in claim 24 , wherein the calculating means further comprises computing the correction term based on the following formula: cf=|r|/(|r|−0.5 rows*cos θ) where cf is the correction term, r is the shortest distance in pixels between the located line to the image center, θ is the angle of the located line with respect to the horizontal, and rows is the number of rows contained in the image being processed.
Claim 31
Dependent Claim
65 words
The system as in claim 22 , wherein step (a) further comprises: (a1) means for generating an edge image from the digital image (a2) means for computing a Hough transform of the edge image; and (a3) means for detecting peaks of a Hough accumulator; and (a4) means for identifying the peaks of the Hough accumulator which correspond to a located line in the digital image.
Claim 32
Dependent Claim
52 words
The system as in claim 27 , wherein the generating means further comprises the steps of: (a11) blurring the digital image with a digital filter; (a12) calculating a gradient of the blurred digital image; and (a13) applying a threshold to the gradient of the blurred digital image for producing the edge image.
Claim 33
Dependent Claim
95 words
The system as in claim 27 , wherein the detecting means further comprises: (a31) means for filtering the Hough accumulator with a matched filter; (a32) means for generating a difference accumulator with the filtered Hough accumulator and the Hough accumulator; (a32) means for applying a threshold to the difference accumulator creating a peak image; (a33) means for identifying local maximum values of the peak image; and (a34) if the local maximum is nonzero and equal to the value of the peak image at any particular location, means for identifying that location as a peak value.
Claim 34
Dependent Claim
28 words
The system as in claim 27 , wherein the identifying means further comprises: (a41) means for identifying those peak values of step (a3) that correspond to located lines.
Claim 35
Dependent Claim
65 words
The system as in claim 22 , wherein step (c) further comprises: (c1) means for re-sampling a row of pixels of the digital image such that the rate of interpolation is dependent on the correction term, and a position of the row of pixels with respect to the central row of pixels; and (c2) repeating the means (c1) for all the other rows of pixels.
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) | 2005-06-03 | 2005-12-03 | 2006-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-06-03 | 2009-12-03 | 2010-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-06-03 | 2013-12-03 | 2014-06-04 | $7700.00 | Window Closed / Lapsed |