Method for determining the concentration of an analyte in a body fluid sample, mobile device, kit, computer program, and computer-readable storage medium.

Abstract

1. A method for determining the concentration of at least one analyte in a sample of a body fluid by using a mobile device (112) having at least one camera (120), comprising: i) capturing, using a camera (120), at least one image of at least a portion of a color reference card (118) and at least a portion of at least one reagent test field (116) of at least one optical test strip (114) to which a sample has been applied; - in the image, the test field (116) is in a defined position relative to the color reference card (118), the color reference card (118) comprises a plurality of different gray reference fields (126) that are locally assigned to the test fields (116), the plurality of gray reference fields (126) and the test fields (116) being locally assigned to each other by being positioned adjacent to each other, or the plurality of gray reference fields (126) that are locally assigned to the test fields (116) being positioned on the color reference card (118) such that the plurality of gray reference fields (126) surround the test fields (116); - capturing at least one image in which a color reference card (118) comprises a plurality of different color reference fields (128) having known reference color values ​​and a plurality of different gray reference fields (126) locally assigned to the color reference fields (128), the plurality of gray reference fields (126) and the color reference fields (128) being locally assigned to each other by being positioned adjacent to each other, or the plurality of gray reference fields (126) locally assigned to the color reference fields (128) being positioned on the color reference card (118) such that the plurality of gray reference fields (126) surround the color reference fields (128); ii) applying at least one predetermined pixel-based average tone map correction to the image acquired in step i), thereby acquiring at least one first intensity-corrected image, wherein the predetermined pixel-based average tone map correction comprises: a first luminance value is recorded by a camera (120), and each pixel of the recorded image is individually corrected by a predetermined method for determining the concentration of at least one analyte in a sample of bodily fluid by using a mobile device (112) having at least one camera (120), the method comprising: i) capturing, by using the camera (120), at least one image of at least a portion of a color reference card (118) and at least a portion of at least one reagent test field (116) of at least one optical test strip (114) to which a sample has been applied, wherein: - in the image, the test field (116) is at a defined position relative to the color reference card (118), - the color reference card (118) comprises a plurality of different gray reference fields (126) locally assigned to the test field (116), and the plurality of gray reference fields (126) and the test field (116) are locally assigned to each other by being located in adjacent positions, or the plurality of gray reference fields (126) locally assigned to the test field (116) are at least one gray reference field (126) locally assigned to the test field (116), The test field (116) is arranged on a color reference card (118) to surround the test field (116), the color reference card (118) comprising a plurality of different color reference fields (128) having known reference color values ​​and a plurality of different gray reference fields (126) locally assigned to the color reference fields (128), the plurality of gray reference fields (126) and the color reference fields (128) being locally assigned to each other by being positioned adjacent to each other, or the plurality of gray reference fields (126) being positioned adjacent to the color reference fields (116). ii) capturing at least one image, in which a plurality of gray reference fields (126) locally assigned to a color reference field (128) are arranged on a color reference card (118) so as to surround a color reference field (128); and ii) applying at least one predetermined pixel-based average tone map correction to the image acquired in step i), thereby acquiring at least one first intensity-corrected image, wherein the predetermined pixel-based average tone map correction comprises an assignment of a second luminance value to a first luminance value, the first luminance value being recorded by a camera (120);obtaining at least one first intensity-corrected image, in which each pixel of the recorded image is individually corrected with a predetermined pixel-based average tone map correction, the average tone map correction being derived by combining multiple tone map corrections for different types of mobile devices; iii) deriving local luminance information (174) for at least a portion of the color reference field (128) and for the test field (116) from the first intensity-corrected image by using a gray reference field (126) locally assigned to the color reference field (128) and the test field (116), respectively, wherein the local luminance information (174) includes a numerical representation describing a local intensity of at least one RGB color in each of the color reference field (128) and the test field (116); iv) applying at least one mobile device specific tone map correction to the first intensity corrected image, where the mobile device specific tone map correction takes into account local luminance information (174), thereby obtaining at least one second intensity corrected image; v) determining the analyte concentration based on the color reaction of the test field (116) by using the second intensity-corrected image; A method comprising:

Claims

1. A method for determining the concentration of at least one analyte in a body fluid sample by using a mobile device (112) having at least one camera (120), i) By using the camera (120), capture at least one image of at least a portion of the color reference card (118) and at least one portion of at least one reagent test field (116) of at least one optical test strip (114) to which the sample has been applied, - In the above image, the test field (116) is in a specified position relative to the color reference card (118), - The color reference card (118) comprises a plurality of different gray reference fields (126) locally assigned to the test field (116), wherein the plurality of gray reference fields (126) and the test field (116) are locally assigned to each other by being positioned adjacent to each other, or the plurality of gray reference fields (126) locally assigned to the test field (116) are arranged on the color reference card (118) such that the plurality of gray reference fields (126) surround the test field (116), - The color reference card (118) comprises a plurality of different color reference fields (128) having known reference color values, and a plurality of different gray reference fields (126) locally assigned to the color reference fields (128), wherein the plurality of gray reference fields (126) and the color reference fields (128) are locally assigned to each other by being positioned adjacent to each other, or the plurality of gray reference fields (126) locally assigned to the color reference fields (128) are arranged on the color reference card (118) such that the plurality of gray reference fields (126) surround the color reference field (128), thereby capturing at least one image. ii) Applying at least one predetermined pixel-based average tonemap correction to the image acquired in step i) to obtain at least one first intensity-corrected image, wherein the predetermined pixel-based average tonemap correction includes assigning a second luminance value to a first luminance value, the first luminance value is recorded by the camera (120), each pixel of the recorded image is individually corrected by the predetermined pixel-based average tonemap correction, and the average tonemap correction is derived by combining a plurality of tonemap corrections for different types of mobile devices, to obtain at least one first intensity-corrected image. iii) Deriving local luminance information (174) for at least a portion of the color reference field (128) and the test field (116) from the first intensity-corrected image by using the gray reference field (126) which is locally assigned to the color reference field (128) and the test field (116), wherein the local luminance information (174) includes a numerical representation describing the local intensity of at least one RGB color in each of the color reference field (128) and the test field (116), iv) Applying at least one mobile device-specific tone map correction to the first intensity-corrected image, wherein the mobile device-specific tone map correction takes into account the local luminance information (174) and thereby obtains at least one second intensity-corrected image; v) Determining the analyte concentration based on the color reaction of the test field (116) by using the second intensity-corrected image. Methods that include...

2. vi) Deriving at least one color correction by using at least some of the color reference fields (128) in the second intensity-corrected image, vii) To obtain at least one intensity-corrected and color-corrected image by applying the color correction to the second intensity-corrected image. The method according to claim 1, further comprising:

3. The method according to claim 2, further comprising, before step vi), some local white balance adjustments of the color reference field (128) and the test field (116).

4. In step vi), the color correction is derived by using the selection of the color reference field (128), and the selection of the color reference field (128) is - Selecting a color reference field (128) within a predetermined subspace of the color space, - Dynamically selecting the color reference field (128) within the color environment of the test field (116) in the color space, - Applying different weights to the color reference field (128), - Select a color reference field (128) according to the accuracy of the color correction. The method according to claim 2 or 3, based on at least one of the following.

5. The method according to any one of claims 1 to 4, wherein the pixel-based average tonemap correction includes at least one of an average tonemap correction derived by combining a plurality of tonemap corrections (166) for various types of mobile devices (112), and the reciprocal of a standard gamma correction.

6. The method according to any one of claims 1 to 5, further comprising performing at least one statistical modification on the first intensity-corrected image, wherein step iv) is performed based on the statistically modified first intensity-corrected image.

7. The method according to any one of claims 1 to 6, wherein the gray reference field (126) locally assigned to the test field (116) surrounds the test field (116), and the test field (116) and the gray reference field (126) locally assigned to the test field (116) form a test field group (154).

8. The method according to claim 7, wherein the test field group (154) comprises a plurality of redundant gray reference fields (126) having at least three different gray levels, with at least two redundant gray reference fields (126) provided for each gray level, the redundant gray reference fields (126) being arranged symmetrically around the test field (116), and in step iii), the local luminance information (174) for the test field (116) is specifically determined by averaging over redundant gray reference fields (126) having the same gray level.

9. The method according to any one of claims 1 to 8, wherein the gray reference field (126) locally assigned to the color reference field (128) surrounds each of the color reference fields (128), and the color reference field (128) and the gray reference field (126) locally assigned to one of the respective color reference fields (128) form a local color reference field group (156).

10. The method according to claim 9, wherein each local color reference field group (156) comprises a plurality of redundant gray reference fields (126) having at least three different gray levels, with at least two redundant gray reference fields (126) provided for each gray level, and the redundant gray reference fields (126) are arranged symmetrically around the color reference field (128) of each of the local color reference field groups.

11. The method according to claim 10, wherein in step iii), the local luminance information (174) of each local color reference field group (156) is determined by averaging over redundant gray reference fields (126) having the same gray level.

12. A mobile device (112) having at least one camera (120), wherein the mobile device (112) comprises at least one processor (122), and the mobile device (112) is configured to perform the method according to any one of claims 1 to 11.

13. A kit (110) for determining the concentration of at least one analyte in a sample of bodily fluids, wherein the kit (110) comprises a mobile device (112) according to claim 12, the kit (110) further comprises at least one optical test strip (114) having at least one reagent test field (116), the kit (110) further comprises at least one color reference card (118), the color reference card (118) comprises a plurality of different gray reference fields (126) locally assigned to the test field (116), the color reference card (118) comprises a plurality of different color reference fields (128) having known reference color values, and a plurality of different gray reference fields (126) locally assigned to the color reference field (128).

14. A computer program including instructions, wherein when the instructions are executed by the mobile device (112) described in claim 12, the computer program causes the mobile device (112) to perform the method according to any one of claims 1 to 11, referring to the method.

15. A computer-readable storage medium containing an instruction, wherein, when the instruction is executed by the mobile device (112) described in claim 12, the mobile device (112) causes the mobile device (112) to perform the method according to any one of claims 1 to 11, referring to the method.

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