Granted Patent B2

US 12,211,237 · App. 17/250,035 · Granted Jan 28, 2025

Inventor: Max Gulde (Freiburg, DE)

Assignee: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.

G06T7/97G01J5/00G06T3/4053G06T5/50G01J2005/0077G06T2207/10032G06T2207/10048G06T2207/20212G06T2207/30181

Abstract

Claims (50)

1. A method for determining a heat map of a territory, the method comprising:

receiving a first thermal image of a first landscape including the territory, wherein the first thermal image is recorded by a recording device included on a first satellite, wherein the first thermal image comprises multiple pixels that are spatially associated with the territory, and wherein the recording device included on the first satellite, pixel by pixel, assigns and includes on the first thermal image, a respective first measured value to the territory;

receiving a second thermal image of a second landscape including the territory, wherein the second thermal image is recorded by a recording device included on a second satellite, wherein the second thermal image comprises multiple pixels that are spatially associated with the territory, and wherein the recording device included on the second satellite, pixel by pixel, in each case assigns and includes on the second thermal image, a second measured value to the territory,

wherein a temporal offset exists between a time at which the first thermal image is recorded and a time at which the second thermal image is recorded, wherein the temporal offset is below an established limit, wherein a radiometric precision of the first thermal image is higher than a radiometric precision of the second thermal image, and wherein a spatial resolution of the second thermal image is higher than a spatial resolution of the first thermal image;

determining, for a first pixel group of the second thermal image, the first pixel group being spatially associated with the territory, and the first pixel group comprising multiple pixels, a measured value offset of the first pixel group using a comparison of relative measured values of at least two pixels of the multiple pixels of the first pixel group of the second thermal image to the first measured value of the at least one pixel of the first thermal image which is at least partially spatially associated with the first pixel group of the second thermal image;

determining a corrected absolute measured value of the pixels of the first pixel group which are associated with the territory, wherein the corrected absolute measured value is based on a second measured value of the at least two pixels of the multiple pixels of the first pixel group and the measured value offset, and

creating a precise heat map of the territory based on the corrected absolute measured value of the pixels of the first pixel group which are associated with the territory.

2. The method according to claim 1 , further comprising:

determining the measured value offset of the first pixel group of the second thermal image using a comparison of relative measured values of at least one pixel of the first pixel group of the second thermal image to the first measured value of the at least one pixel of the first thermal image which is spatially associated with the first pixel group of the second thermal image.

3. The method according to claim 1 , further comprising:

determining a land surface temperature of the territory based on the precise heat map and at least one of a land surface model or an emission model.

4. The method according to claim 1 , wherein at least one of the first thermal image or the second thermal image is an infrared image.

5. The method according to claim 1 , wherein the spatial resolution of the second thermal image is at least one of: one order of magnitude higher or two orders of magnitude higher than the spatial resolution of the first thermal image.

6. The method according to claim 1 , wherein the first measured value and the second measured value are temperature values, wherein a radiometric deviation of the first thermal image per pixel is less than 2 K, and wherein a radiometric deviation of the second thermal image is, on average, greater than 2 K.

7. The method according to claim 1 , wherein the recording device included on the first satellite is calibrated so as to increase radiometric precision of the recording device included on the first satellite.

8. The method according to claim 1 , wherein the first thermal image is recorded by the recording device included on at least one of a geostationary satellite in a high Earth orbit or a non-geostationary satellite in a low Earth orbit.

9. The method according to claim 1 , wherein the second thermal image is recorded by the recording device included on a satellite smaller in size than the satellite on which the recording device that records the first thermal image is included.

10. The method according to claim 1 , further comprising:

determining a first heat map of the territory at a first point in time using a first received thermal image and a second received thermal image;

determining a second heat map of the territory at a second point in time using a third received thermal image and a fourth received thermal image; and

creating a time series of a temperature of the territory based on the first and second heat maps.

11. The method according to claim 10 , wherein the first and second points in time are within an established time period, wherein the first thermal image and third thermal image each have a higher radiometric precision than at least one of the second thermal image or the fourth thermal image, wherein the first thermal image and the third thermal image are each recorded by a recording device included on a first satellite platform, wherein the second thermal image has a higher spatial resolution than at least one of the first thermal image or the third thermal image and recorded by a recording device included on a second satellite, wherein the fourth thermal image has a higher spatial resolution than at least one of the first thermal image or the third thermal image and is recorded by a recording device included on a third satellite, and wherein the second satellite and the third satellite are each smaller than the first satellite platform.

12. The method according to claim 10 , further comprising:

determining multiple additional heat maps of the territory at additional points in time, wherein two consecutive points in time of the additional points in time are in each case within an established time period; and

creating a time series of a temperature of the territory based on the first heat map, the second heat map, and the additional heat maps.

13. A device for creating a heat map of a territory, comprising:

at least one receiving unit configured to:

receive a first thermal image of a first landscape including the territory, recorded by a recording device included on a first satellite, wherein the first thermal image comprises multiple pixels that are spatially associated with the territory, and wherein the recording device included on the first satellite, pixel by pixel, assigns and includes on the first thermal image, a respective first measured value to the territory; and

receive a second thermal image of a second landscape including the territory, recorded by a recording device of a second satellite, wherein the second thermal image comprises multiple pixels that are spatially associated with the territory, and the recording device included on the second satellite, pixel by pixel, assigns and includes on the second thermal image, a second measured value to the territory, wherein a temporal offset exists between a time at which the first thermal image is recorded and a time at which the second thermal image is recorded, the temporal offset being below an established limit, wherein a radiometric precision of the first thermal image is higher than a radiometric precision of the second thermal image, and wherein and a spatial resolution of the second thermal image is higher than a spatial resolution of the first thermal image; and

a determination unit configured to:

determine, for a first pixel group of the second thermal image, the first pixel group being spatially associated with the territory, the first pixel group comprising multiple pixels, a measured value offset of the first pixel group using a comparison of relative measured values of at least two pixels of the multiple pixels of the first pixel group to the first measured value of the at least one pixel of the first thermal image, which is at least partially spatially associated with the first pixel group of the second thermal image;

determine corrected absolute measured values of the pixels of the first pixel group, based on a second measured value of the at least two pixels of the multiple pixels of the first pixel group and the measured value offset; and

create the heat map of the territory based on the corrected absolute measured values.

14. The device according to claim 13 , wherein the determination unit is further configured to:

determine a land surface temperature of the territory based on the heat map and at least one of a land surface model or an emission model.

15. The device according to claim 13 , wherein at least one of the first thermal image or the second thermal image is an infrared image.

16. The device according to claim 13 , wherein the spatial resolution of the second thermal image is at least one of one order of magnitude higher or two orders of magnitude higher than the spatial resolution of the first thermal image.

17. The device according to claim 13 , wherein the first measured value and the second measured value are temperature values.

18. The device according to claim 13 , wherein the recording device included on the first satellite is calibrated to increase radiometric precision of the recording device included on the first satellite, wherein a radiometric deviation of the first thermal image per pixel is less than 2 K, and wherein a radiometric deviation of the second thermal image is, on average, greater than 2 K.

19. A device for creating a heat map of a territory, the device comprising:

at least one receiving unit configured to:

receive a first thermal image of a first landscape including the territory recorded by a recording device included on a first satellite, wherein the first thermal image comprises multiple pixels that are spatially associated with the territory and wherein the recording device included on the first satellite, pixel by pixel, assigns and includes on the first thermal image, a respective first measured value of the territory; and

receive a second thermal image of a second landscape including the territory, recorded by a recording device of a second satellite, wherein the second thermal image comprises multiple pixels that are spatially associated with the territory, and the recording device included on the second satellite, pixel by pixel, assigns and includes on the second thermal image, a second measured value to the territory, wherein a temporal offset exists between a time at which the first thermal image is recorded, the temporal offset being below an established limit, where a radiometric precision of the first thermal image is higher than a radiometric precision of the second thermal image, and wherein a spatial resolution of the second thermal image is higher than a spatial resolution of the first thermal image; and

a determination unit configured to:

determine, for a first pixel group of the second thermal image, the first pixel group being spatially associated with the territory, the first pixel group comprising multiple pixels, a measured value offset of the first pixel group using a comparison of relative measured values of at least two pixels of the multiple pixels of the first pixel group to the first measured value of the at least one pixel of the first thermal image, which is at least partially spatially associated with the first pixel group of the second thermal image;

determine corrected absolute measured values of the pixels of the first pixel group, based on a second measured value of the at least two pixels of the multiple pixels of the first pixel group and the measured value offset;

create the heat map of the territory based on the corrected absolute measured values; and

determine a land surface temperature of the territory based on the heat map and at least one of a land surface model or an emission model;

wherein at least one of the first thermal image or the second thermal image is an infrared image, and wherein the spatial resolution of the second thermal image is at least one of: one order of magnitude higher or two orders of magnitude higher than the spatial resolution of the first thermal image.

20. The device according to claim 19 , wherein the recording device included on the first satellite is calibrated to increase radiometric precision of the recording device included on the first satellite, wherein a radiometric deviation of the first thermal image per pixel is less than 2 K, and wherein a radiometric deviation of the second thermal image is, on average, greater than 2 K.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (26)