IR CAMERA AND METHOD FOR PROCESSING THERMAL IMAGE INFORMATION

• US 20130222604A1
• Filed: 04/03/2013
• Published: 08/29/2013
• Est. Priority Date: 10/04/2010
• Status: Active Grant

• Current Assignee: Flir Systems AB (Teledyne Technologies Incorporated)
• Original Assignee: Flir Systems AB (Teledyne Technologies Incorporated)
• Inventors: Ingerhed, Malin, Rohlin, Gran
• Granted Patent: US 9,807,318 B2
• Time in Patent Office: Days
• US Class Current: 348/164
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/162 User input
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/507 using conditional replenishment
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 23/23 from thermal infrared radiation
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A method for processing information from an IR detector of an IR camera, for an embodiment, comprises receiving a series of frames of data from said IR detector being operable to detect IR radiation from a scene, said frames of IR data representing detected IR radiation; performing a compression of said frames of IR data; wherein each data value together with calibration data uniquely represents measured IR radiation from the scene.

Claims

1. A method for processing information from an infrared (IR) detector of an IR camera, the method comprising:

receiving a series of frames of IR data values from said IR detector being operable to detect IR radiation from a scene, said frames of IR data representing detected IR radiation; and

performing a compression of said frames of IR data values;

wherein each received IR data value together with calibration data uniquely represents measured IR radiation from the scene, wherein calibration data comprises a unique mapping between the received IR data values and the corresponding measured IR radiation from the scene.

2. The method of claim 1, further comprising storing said compressed IR frames of IR data values in a memory.

3. The method of claim 1, further comprising:

performing a decompression of said frames of IR data values,

wherein each IR data value together with calibration data uniquely represents measured IR radiation from the scene.

4. The method of claim 3, further comprising:

transforming decompressed calibrated IR data values of said frames of IR data values to a color space to obtain a series of displayable IR images.

5. The method of claim 4, wherein the transformation to a color space is non-reversible.

6. The method of claim 3, further comprising performing data analysis or other operations on decompressed IR data values.

7. The method of claim 1, further comprising:

performing calibration operations on said series of IR data values frames in order to render said IR data values frames radiometric, thereby obtaining a series of calibrated frames of IR data values with a unique mapping between the IR data values and the corresponding measured IR radiation from the scene.

8. The method of claim 3, wherein said calibration operations is performed before compression or after decompression.

9. The method of claim 8, wherein:

when calibration is performed before compression, the compression and decompression is performed such that the radiometric properties of the uncompressed calibrated IR data values frames are substantially maintained after compression and decompression, i.e. the frames of decompressed calibrated IR data values have a unique mapping between the IR data values and the corresponding measured IR radiation.

10. The method of claim 3, wherein compression and/or decompression comprises applying video compression techniques on frames of IR data values.

11. The method of claim 1, further comprising:

e) receiving a series of frames of IR data values from an IR detector operable to detect IR radiation from a scene;

f) performing calibration operations on said series of IR data values frames in order to render said IR data values frames radiometric, thereby obtaining a series of calibrated frames of IR data values with a unique mapping between the IR data values and the corresponding measured IR radiation from the scene;

g) performing a compression of said calibrated IR data values frames to yield a series of compressed calibrated IR data values frames in such a way that a corresponding decompression of the compressed calibrated IR data values frames can be performed, and

h) performing decompression of said compressed calibrated IR data values frames arriving at a series of calibrated IR data values frames.

12. The method of claim 11, further comprising transforming the decompressed calibrated IR data values to a color space to obtain a series of displayable IR images.

13. The method of claim 1, further comprising:

i) receiving a series of frames of IR data values from an IR detector operable to detect IR radiation from a scene;

j) performing a compression of said calibrated IR data values frames to yield a series of compressed calibrated IR data values frames in such a way that a corresponding decompression of the compressed calibrated IR data values frames can be performed,

k) performing decompression of said compressed calibrated IR data values frames arriving at a series of calibrated IR data values frames with substantially maintained radiometric properties, i.e. the frames of decompressed calibrated IR data values have a unique mapping between the IR data values and the corresponding measured IR radiation from the scene; and

l) performing calibration operations on said series of IR data values frames in order to render said IR data values frames radiometric, thereby obtaining a series of calibrated frames of IR data values with a unique mapping between the IR data values and the corresponding measured IR radiation from the scene.

14. The method of claim 13, further comprising transforming the decompressed calibrated IR data values to a color space to obtain a series of displayable IR images.

29. A non-transitory computer program product for use in a processor of an IR camera comprising code portions adapted to perform the method of claim 1.

30. A non-transitory computer program product for use in a processor of a processing unit comprising code portions adapted to perform the method of claim 1.

15. A method for processing information from an IR camera, the method comprising:

e) receiving a series of IR images in the form of data from an IR sensor,

f) performing calibration operations on said series of IR images in order to render said IR images radiometric

g) performing a compression of said IR images to yield a series of compressed IR images in such a way that a corresponding decompression of the compressed IR images can be performed, and

h) after performing the steps a), b) and c) arriving at a series of radiometric IR images.

16. The method according to claim 15, wherein step b) is performed before step c).

17. The method according to claim 15, wherein step b) is performed after step c).

18. The method according to claim 15, wherein said compression further comprises:

i) analyzing a first image belonging to said series of IR images;

j) performing a first compression according to a first compression method on said first image to achieve an intermediate image with a first compression ratio dependent on information from step e);

k) determining a second compression ratio dependent on a combined compression ratio, said combined compression ratio comprising said first compression ratio and said second compression ratio; and

l) performing a second compression according to a second compression method on said first image to achieve said compressed image with the second compression ratio dependent on information from step g), wherein said combined compression ratio is dependent on at least one system parameter.

19. The method of claim 18, wherein said system parameter is a transmission bandwidth.

20. The method of claim 18, wherein said system parameter is a property of a memory unit.

21. The method of claim 18, wherein said combined compression ratio is determined by a combined compression ratio of at least one other image belonging to the series.

22. The method of claim 18, wherein said combined compression ratio is a preset value.

23. The method of claim 18, wherein said first compression is a video compression.

24. The method of claim 18, wherein the method is performed by a processor in an IR camera.

25. The method of claim 18, wherein the method is performed by a processor in a processing unit receiving a series of frames of IR data representing detected IR radiation.

26. An IR camera, comprising:

an IR detector operable to detect IR radiation from a scene; and

a processor operable to process information from the IR detector, said processor adapted to;

receive a series of frames of data from the IR detector, said frames of IR data representing detected IR radiation; and

perform a compression of said frames of IR data;

wherein each data value together with calibration data uniquely represents measured IR radiation from the scene.

27. An IR camera, comprising:

capture means for capturing an infrared image;

processing means for receiving and processing said image from said capture means; and

storage means for storing said infrared image;

wherein said processing means is arranged to perform calibration operations and to perform a compression of said image in such a way that said images after a corresponding decompression are radiometric images.

28. An IR camera according to claim 27, wherein said processing means are further arranged to determine at least one system parameter of said IR camera and determine a combined compression ratio depending on said system parameter and further being arranged to perform a first compression and second compression on an infrared image in such a way that a second compression ratio of said second compression is determined by a first compression ratio of said first compression and by said combined compression ratio.