Method of detecting the orientation of an object in an image
View Patent ↗A method of detecting the orientation of a radiographic image represented by a digital signal representation wherein mathematical moments of the digital signal representation are calculated relative to different reference entities and wherein a decision on the orientation of the radiographic image, for example the position of the thorax edge in a mammographic image, is obtained on the basis of an extreme value (minimum, maximum) of the calculated moments.
1. A method of detecting the orientation of a radiographic image represented by a digital signal representation comprising:
calculating, via a medical computer system, mathematical moments of said digital signal representation relative to different reference entities; and
obtaining, via the medical computer system, a decision on the orientation of said radiographic image on the basis of an extreme value comprising one of a maximum and a minimum of the calculated moments, wherein said moments are one-dimensional moments obtained by projecting the digital signal representation of said image onto a predefined axis.
2. The method according to claim 1 wherein said axis is parallel to one of the boundaries of said image.
3. A method of detecting the orientation of a radiographic image represented by a digital signal representation comprising:
calculating, via a medical computer system, mathematical moments of said digital signal representation relative to different reference entities; and
obtaining, via the medical computer system, a decision on the orientation of said radiographic image on the basis of an extreme value comprising one of a maximum and a minimum of the calculated moments, wherein said digital signal representation is a function of at least one derivative of an original digital signal representation.
4. The method according to claim 3 wherein said derivative is the first order edge gradient.
5. A method of detecting the orientation of a radiographic image represented by a digital signal representation comprising:
calculating, via a medical computer system, mathematical moments of said digital signal representation relative to different reference entities; and
obtaining, via the medical computer system, a decision on the orientation of said radiographic image on the basis of an extreme value comprising one of a maximum and a minimum of the calculated moments, wherein collimation area are excluded from said digital signal representation.
6. A method of detecting the orientation of a radiographic image represented by a digital signal representation comprising:
calculating, via a medical computer system, mathematical moments of said digital signal representation relative to different reference entities; and
obtaining, via the medical computer system, a decision on the orientation of said radiographic image on the basis of an extreme value comprising one of a maximum and a minimum of the calculated moments, wherein direct exposure area are excluded from said digital signal representation.
7. The method according to claim 6 wherein a moment is a cartesian moment which moment weights the digital signal representation by a function of at least one spatial coordinate x or y.
8. The method according to claim 7 wherein a moment is calculated with respect to a cartesian co-ordinate system the axes of which are substantially parallel to the boundaries of said image.
9. The method according to claim 6 wherein said moments are two-dimensional moments.
10. The method according to claim 6 wherein a moment is generated with respect to at least one predefined point.
11. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 7 .
12. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 8 .
13. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 9 .
14. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 1 .
15. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 2 .
16. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 10 .
17. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 3 .
18. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 4 .
19. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 5 .
20. A non-transitory computer readable medium comprising computer executable program code adapted to carry out the steps of claim 6 .