WHITE TURBID STATE DIAGNOSTIC APPARATUS

• US 20140002654A1
• Filed: 06/26/2013
• Published: 01/02/2014
• Est. Priority Date: 06/27/2012
• Status: Active Grant

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Clarion Co., Ltd. (Faurecia SA)
• Inventors: IRIE, Kota, MURAMATSU, Shoji, KONDOU, Shunsuke, KIYOHARA, Masahiro
• Granted Patent: US 9,286,519 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/0002 Inspection of images, e.g. flaw detection
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle

Abstract

A white turbid state diagnostic apparatus has an imaging part installed on a vehicle and configured to convert a light signal from a periphery of the vehicle into an image signal, a region detection part configured to detect a region from the image signal, the region being constituted by pixels having brightness values over a predetermined brightness and being in a substantially circular shape having a predetermined area or more, a brightness gradient calculation part configured to calculate a brightness gradient on a line which is directed from a predetermined position in a predetermined direction based on brightness values of pixels on the line in the region, and a white turbid level calculation part configured to calculate a white turbid level of the lens based on the brightness gradient.

Claims

1. A white turbid state diagnostic apparatus, comprising

an imaging part installed on a vehicle and configured to observe a periphery of a vehicle via a lens, the imaging part having a photoelectric conversion section configured to convert a light signal of the observed periphery of the vehicle into an image signal;

a region detection part configured to detect a region from the image signal, the region being constituted by pixels having brightness values over a predetermined brightness and being in a substantially circular shape having a predetermined area or more;

a brightness gradient calculation part configured to calculate a brightness gradient on a line which is directed from a predetermined position in a predetermined direction based on brightness values of pixels on the line in the region; and

a white turbid level calculation part configured to calculate a white turbid level of the lens based on the brightness gradient.

2. The lens white turbid status diagnostic apparatus according to claim 1, wherein the imaging part has a gain adjustment section configured to adjust a gain for converting the light signal into the image signal according to brightness of the periphery of the vehicle;

and

if the gain is larger than a predetermined value, the white turbid level calculation part calculates the white turbid level.

3. The white turbid state diagnostic apparatus according to claim 1, wherein

a starting point of the line has a horizontal position being at a horizontal position of a centroid position and a vertical position being at a position between a horizontal line passing the centroid position of the region and a horizontal line passing an upmost position of the region;

the line extends in a leftward or a rightward direction from the starting point in the image signal.

4. The white turbid state diagnostic apparatus according to claim 1, wherein

the line extends from a centroid position of the region to a circumferential edge of the region;

and

a starting point of the line has a vertical position which is between a horizontal line passing the centroid position of the region and a horizontal line passing an upmost position of the region.

5. The white turbid state diagnostic apparatus according to claim 3, wherein the line is constituted by a plurality of lines in combination.

6. The white turbid state diagnostic apparatus according to claim 5, wherein the line is constituted by a plurality of lines having a bilaterally symmetric relationship with respect to a line passing the centroid position of the region and extending vertically in the image signal.

7. The white turbid state diagnostic apparatus according to claim 1, wherein the region is a region formed by a lighting headlight of another vehicle imaged by the imaging part.

8. The white turbid state diagnostic apparatus according to claim 7, wherein the another vehicle is a vehicle running in a same lane as the vehicle at a backward position.

9. The white turbid state diagnostic apparatus according to claim 1, wherein the brightness gradient is calculated as a number of pixels on the line between a position where the brightness value on the line goes down under a first threshold value to a position where the brightness value on the line goes down under a second threshold value which is less than the first threshold value in a direction extending from a starting point of the line set in the image signal along the line.

10. The white turbid state diagnostic apparatus according to claim 1, wherein the white turbid level calculation part has

a brightness gradient average value calculation section configured to calculate an average value of the brightness gradient calculated on the line to obtain a white turbid level;

a similarity calculation section configured to calculate a similarity of regions detected from image signals imaged at different timings; and

a certainty determination section configured to determine a certainty of the white turbid level according to a period where high similarities are continuously calculated.

11. The white turbid state diagnostic apparatus according to claim 1, wherein the similarity calculation section judges that the similarity is high when a ratio of an average value of a plurality of previous white turbid levels and the latest white turbid level is within a predetermined range.

12. The white turbid state diagnostic apparatus according to claim 2, wherein the brightness gradient calculation part corrects the brightness gradient based on a gain adjusted by the gain adjustment section.

13. The white turbid state diagnostic apparatus according to claim 12, wherein the brightness gradient calculation part corrects the brightness gradient by being multiplied by a logarithmic nature of the gain adjusted by the gain adjustment section when the gain adjusted by the gain adjustment section is less than a predetermined gain, and corrects the brightness gradient by being multiplied by a logarithmic nature of the predetermined gain when the gain adjusted by the gain adjustment section is the predetermined gain or more.