Adaptive threshold sigma-delta algorithm movement detection device and method
AssigneeCommissariat a l'Energie Atomique
InventorArnaud VERDANT
Life of this patent
Estimating the term…
Abstract
Movement detection method comprising at least the following steps: the calculation of an envelope signal En of a signal Sn, designed to be supplied by at least one pixel of a pixel matrix and corresponding to an n-th captured image; the calculation of a first mean M1n of the signal En in function of the signal En and/or M1n-1; the calculation of a signal γn=En×M1n; the calculation of a second mean M2n of the signal γn in function of the signal γn and/or M2n-1; the calculation of a third mean M3n of the signal Sn in function of the signal Sn and/or M3n-1 and/or the signal M2n; the calculation of a signal Δn=|Sn−M3n|; a comparison between the signals Δn and M2n, wherein a movement is considered as detected when Δn>M2n; where n: natural whole number.
Claims18
A movement detection method comprising at least the following steps:
- the calculation of an envelope signal En of a signal Sn, designed to be supplied by at least one pixel of a pixel matrix and corresponding to an n-th captured image, equal to the absolute value of the difference between the signal Sn and a value Sa, where aε[0;n], corresponding to a final extreme value reached by Sn for which the sign of the value
-
- S
- n
-
- n
-
- |
- n
- =
- a
- is different from the sign of the value
-
- S
- n
-
- n
-
- |
- n
- =
- a
- -
- 1
- ;
- the calculation of a first mean M1n of the signal En in function of the value of the signal En and/or a previous value M1n-1;
- the calculation of a signal γn=En×M1n;
- the calculation of a second mean M2n of the signal γn in function of the value of the signal γn and/or a previous value M2n-1;
- the calculation of a third mean M3n of the signal Sn in function of the value of the signal Sn and/or a previous value M3n-1 and/or the value of the signal M2n;
- the calculation of a signal Δn=|Sn−M3n|;
- a comparison between the signals Δn and M2n, wherein a movement is considered as detected when Δn>M2n;
- where n:
- natural whole number.
A movement detection device comprising at least:
- means of calculating an envelope signal En of a signal Sn designed to be supplied by at least one pixel of a pixel matrix and corresponding to an n-th captured image, equal to the absolute value of the difference between the signal Sn and a value Sa, with aε[0;n], corresponding to a final extreme value reached by Sn for which the sign of the value
-
- S
- n
-
- n
-
- |
- n
- =
- a
- is different from the sign of the value
-
- S
- n
-
- n
-
- |
- n
- =
- a
- -
- 1
- ;
- means of calculating a first mean M1n of the signal En in function of the value of the signal En and/or a previous value M1n-1;
- means of calculating a signal γn=En×M1n;
- means of calculating a second mean M2n of the signal γn in function of the value of the signal γn and/or a previous value M2n-1;
- means of calculating a third mean M3n of the signal Sn in function of the value of the signal Sn and/or a previous value M3n-1 and/or the value of the signal M2n
- means of calculating a signal Δn=|Sn−M3n|;
- means of comparing the signals Δn and M2n, wherein a movement is considered as detected when Δn>M2n;
- where n:
- natural whole number.
Dependencies are inferred from the claim text.