METHOD FOR A TOUCHLESS DETERMINATION OF THE TEMPERATURE OF AN OBJECT AND CORRESPONDING THERMAL IMAGING CAMERA

• US 20120086810A1
• Filed: 10/07/2011
• Published: 04/12/2012
• Est. Priority Date: 10/09/2010
• Status: Abandoned Application

• Current Assignee: Testo AG
• Original Assignee: Testo AG
• Inventors: Messerschmid, Andreas
• Application Number:
  US13/268,013
• Publication Number:
  US 20120086810A1
• Time in Patent Office: Days
• US Class Current: 348/164
• CPC Class Codes: A61B 5/015 By temperature mapping of body part
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/025 Interfacing a pyrometer to an external device or network; User interface
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/0846 having multiple detectors for performing different types of detection, e.g. using radiometry and reflectometry channels
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 5/272 Means for inserting a foreground image in a background image, i.e. inlay, outlay
• 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 a touchless determination of the temperature of an object (13) in which at least one IR-image (10) and at least one VIS-image (12) of the object (13) are generated with an IR-detector unit (2) and with a VIS-detector unit (3) of a thermal imaging camera (1), a feature detection (16) is applied to the IR-image (10) and/or the VIS-image (12), thus extracting features (17), and identifying the object (13) from the features (17) extracted and present as a result of the feature detection (16), and to determine and display from the IR-image (10) at least one temperature value (25) of the object (13).

Claims

1. A method for touchless determination of a temperature of an object (13), comprising:

in a first step (9, 11, 14) generating at least one IR-image (10) and at least one VIS-image (12) of the object (13),

in a second step (15) feeding the at least one IR-image (10) and the at least one VIS-image (12) to a feature detection device (6),

in a third step (26) performing at least one feature detection (16) on the images supplied with the feature detection device (6),

in a fourth step (18), using the result (17) of at least one feature detection (16), identifying the object (13) in an object identification, and

in a fifth step (21), using the at least one IR-image (10), determining and displaying at least one temperature value (25) of the identified object (13).

2. The method according to claim 1, wherein the at least one IR-image (10) and the at least one VIS-image (12) are fed to the feature recognition device (6) in the second step (15), by a joint image being calculated from the at least one IR-image (10) and from the at least one VIS-image (12), which includes joint image information from both the IR-image (10) as well as the VIS-image (12), with the at least one feature detection (16) being performed on the joint image in the third step (26).

3. The method according to claim 1, wherein in the third step (26) a first feature detection (16) is performed at least on one of the IR-images (10) in the feature detection device (6) and a second feature detection (16) is performed at least on one of the VIS-images (12), with a joint data field being deduced pixel-wise from respective results (17) of the feature detections (16), which in the fourth step (18) are processed for identifying the object (13) as a result of the at least one feature detection (16).

4. The method according to claim 3, wherein the joint data field is deduced pixel-wise by adding, subtracting, or multiplying values of a data field of the result (17) of the first feature detection (16) with a data field of the result of the second feature detection (16).

5. The method according to claim 4, wherein the at least one IR-image (10) is an element of an IR-image sequence of IR-images (10) and the object identification (18) is controlled such that an object (13) is identified in the IR-image (10), which has previously been identified in the IR-image (10) of a previous IR-image sequence.

6. The method according to claim 2, wherein in the second step (15) the joint image is calculated with a constant or an image-position dependent mixing factor.

7. The method according to claim 1, wherein the at least one feature recognition (16) in the third step (26) utilizes a Harris-Corner-detector for object identification in the fourth step (18).

8. The method according to claim 1, wherein in the third step (26) first a feature recognition (16) is performed in the IR-image (10) supplied, and subsequently the result (17) of the feature recognition (16) is checked for suitability for object identification (18) by deducing a suitability value from the result (17), and in case the suitability values falls short of a suitability threshold, a second feature detection (16) is performed in the VIS-image (12) supplied, and the result (17) of the second feature detection (16) or both feature detections (16) is processed in the fourth step (18) as the result (17) of the feature detection (16).

9. The method according to claim 1, wherein in the third step (26), the second feature detection (16) is controlled depending on a deduced suitability value.

10. A thermal imaging camera (1) with an IR-detector unit (2), which is equipped to record an IR-image (10), with a VIS-detector unit (3), which is equipped to record a VIS-image (12), with a data processing device (4) and a display unit (5), which is connected to the data processing unit (4), wherein a feature detection device (6) is realized with the data processing device (4) and the data processing device (4) is equipped to perform a method according to claim 1.