ENHANCED VISUAL REPRESENTATION OF INFRARED DATA VALUES

• US 20150124102A1
• Filed: 11/03/2014
• Published: 05/07/2015
• Est. Priority Date: 11/01/2013
• Status: Active Grant

• Current Assignee: Flir Systems AB (Teledyne Technologies Incorporated)
• Original Assignee: Flir Systems AB (Teledyne Technologies Incorporated)
• Inventors: Erlandsson, Mikael, Frost, Walter, Von Braun, Fredrik
• Granted Patent: US 10,298,859 B2
• Time in Patent Office: Days
• US Class Current: 348/165
• CPC Class Codes: H04N 1/465 Conversion of monochrome to colour
• CPC Class Codes: H04N 23/23 from thermal infrared radiation
• CPC Class Codes: H04N 23/84 for processing colour signals
• 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
• CPC Class Codes: H04N 9/43 Conversion of monochrome picture signals to colour picture signals for colour picture display
• CPC Class Codes: H04N 9/64 Circuits for processing colour signals H04N9/77 takes precedence; camera processing pipelines for processing colour signals H04N23/84

Abstract

Various techniques are provided to generate enhanced visual representations of captured infrared (IR) data values. For example, various methods, systems, devices, and machine-readable mediums are provided that may be used to map color and/or grayscale values to temperature values. Such mapping permits a user to intuitively interpret the temperatures associated with the IR data values. The temperatures may be presented as a visual representation of the captured IR data values having an enhanced contrast.

Claims

1. A method comprising:

receiving a frame of infrared (IR) data values captured by a detector comprising a plurality of detector elements, wherein the frame comprises, for each detector element, a pixel having an assigned one of the IR data values representing a temperature value associated with infrared radiation emitted from an observed real world scene and received by the detector element; and

generating a visual representation of at least a portion of the IR data values assigned to a corresponding set of the pixels, wherein the visual representation comprises, for each pixel, at least one color-representing component and a grayscale component according to a color model, and wherein the generating the visual representation comprises;

assigning, for each pixel, a value to the at least one color-representing component based on the IR data value of the pixel and according to a first mapping between IR data values representing temperatures and color-representing component values from a palette, the first mapping being invariable with respect to the range of the captured IR data values in the frame so as to maintain a fixed temperature-to-color mapping, and

assigning, for each pixel, a value to the grayscale-representing component based on the IR data value of the pixel and according to a second mapping between IR data values and grayscale-representing component values from the palette, the second mapping being independent of the first mapping.

2. The method of claim 1, wherein the second mapping periodically varies grayscale-representing component values in relation to IR data values.

3. The method of claim 2, the second mapping periodically varies grayscale-representing component values in relation to IR data values according to one or more sinusoidal wave functions or one or more saw-tooth patterns.

4. The method of claim 3, wherein the one or more sinusoidal wave functions comprises a plurality of sinusoidal wave functions each having a corresponding period and each associated with a corresponding sub-range from a range of IR data values.

5. The method of claim 1, wherein the second mapping dynamically maps IR data values to grayscale-representing component values relative to the range of all captured IR data values in the frame.

6. The method of claim 1, wherein:

the color model is a hue-saturation-value (HSV) model;

the at least one color-representing component comprises a hue component and/or a saturation component; and

the grayscale-representing component comprises a value component representing lightness.

7. The method of claim 1, further comprising receiving a control signal, wherein:

the palette comprises a predefined set of color-representing component values and grayscale-representing component values to be used in the generating of the visual representation; and

the palette is selected from a predefined set of palettes based on the received control signal.

8. The method of claim 7, wherein the control signal is indicative of a type of use of the visual representation of the IR data values.

9. The method of claim 1, wherein the first and the second mapping are defined as part of the palette.

10. The method of claim 1, wherein the portion of the IR data values comprises all of the IR data values of the frame.

11. A system comprising:

a focal plane array (FPA) comprising a plurality of detector elements responsive to infrared (IR) radiation emitted from an observed real world scene; and

a processor configured to;

receive a frame of IR data values captured by the FPA, wherein the frame comprises, for each detector element of the FPA, a pixel having an assigned one of the IR data values representing a temperature value associated with the infrared radiation emitted from the observed real world scene and received by the FPA, and

generate a visual representation of at least a portion of the IR data values assigned to a corresponding set of the pixels, wherein the visual representation comprises, for each pixel, at least one color-representing component and a grayscale component according to a color model, and wherein the processor is configured to generate the visual representation by;

assigning, for each pixel, a value to the at least one color-representing component based on the IR data value of the pixel and according to a first mapping between IR data values representing temperatures and color-representing component values from a palette, the first mapping being invariable with respect to the range of the captured IR data values in the frame so as to maintain a fixed temperature-to-color mapping, and

assigning, for each pixel, a value to the grayscale-representing component based on the IR data value of the pixel and according to a second mapping between IR data values and grayscale-representing component values from the palette, the second mapping being independent of the first mapping.

12. The system of claim 11, wherein the second mapping periodically varies grayscale-representing component values in relation to IR data values.

13. The system of claim 12, the second mapping periodically varies grayscale-representing component values in relation to IR data values according to one or more sinusoidal wave functions or one or more saw-tooth patterns.

14. The system of claim 13, wherein the one or more sinusoidal wave functions comprises a plurality of sinusoidal wave functions each having a corresponding period and each associated with a corresponding sub-range from a range of IR data values.

15. The system of claim 11, wherein the second mapping dynamically maps IR data values to grayscale-representing component values relative to the range of all captured IR data values in the frame.

16. The system of claim 11, wherein:

the color model is a hue-saturation-value (HSV) model;

the at least one color-representing component comprises a hue component and/or a saturation component; and

the grayscale-representing component comprises a value component representing lightness.

17. The system of claim 11, further comprising an input device configured to receive a manual user input and to send the control signal to the processor in response to the received manual user input, wherein:

the palette comprises a predefined set of color-representing component values and grayscale-representing component values to be used in the generating of the visual representation; and

the processor is configured to select the palette from a predefined set of palettes based on the control signal.

18. The system of claim 17, wherein the control signal is indicative of a type of use of the visual representation of the IR data values.

19. The system of claim 11, further comprising a display device configured to present the visual representation as an image, wherein the processor is configured to convert the visual representation into a color model associated with the display device.

20. A machine-readable medium storing non-transitory information comprising a plurality of machine-readable instructions which, when executed by one or more processors of a system, are configured to cause the system to perform a method comprising:

receiving a frame of infrared (IR) data values captured by a detector comprising a plurality of detector elements, wherein the frame comprises, for each detector element, a pixel having an assigned one of the IR data values representing a temperature value associated with infrared radiation emitted from an observed real world scene and received by the detector element; and

generating a visual representation of at least a portion of the IR data values assigned to a corresponding set of the pixels, wherein the visual representation comprises, for each pixel, at least one color-representing component and a grayscale component according to a color model, and wherein the generating the visual representation comprises;

assigning, for each pixel, a value to the at least one color-representing component based on the IR data value of the pixel and according to a first mapping between IR data values representing temperatures and color-representing component values from a palette, the first mapping being invariable with respect to the range of the captured IR data values in the frame so as to maintain a fixed temperature-to-color mapping, and

assigning, for each pixel, a value to the grayscale-representing component based on the IR data value of the pixel and according to a second mapping between IR data values and grayscale-representing component values from the palette, the second mapping being independent of the first mapping.