JP2009031004A - Potation determiner and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately determine the state of potation without touching a determining object person. <P>SOLUTION: An imaging picture in a specific wavelength band of a near-infrared wavelength band and an imaging picture in a visible light band are acquired from an imaging device (100). A domain representing a specific part, where light absorption characteristics owing to ethanol are expressed, is detected from each of the imaging pictures (102). The ratio of a luminance value in a domain representing a specific part of the imaging picture in the visible light band to a luminance value in a domain representing a specific part of the imaging picture in the specific wavelength band is calculated as a characteristic amount representing the absorbed amount of light (104). The state of potation of a driver is determined according to whether or not the calculated characteristic amount is less than a previously determined threshold (106). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drinking determination device and a program, and more particularly to a drinking determination device and a program for determining a drinking state of a determination target person.

  Conventionally, a light source that emits near-infrared light, an imaging unit that is sensitive to near-infrared light, and an image processing unit that inputs and processes an image of a captured finger are provided, and security control is performed. There is known a finger authentication device that analyzes biological information of a finger acquired at the same time as imaging or a temporal change thereof and measures a biological state such as health and physical condition (Patent Document 1). In this finger authentication device, biometric authentication technology and health diagnosis technology are combined, and operability that is easy to use is realized.

In addition, a laser beam with an alcohol absorption wavelength is emitted from the laser diode toward the traveling vehicle, a laser beam with a reference wavelength is emitted from the laser diode with a time difference, and both laser beams are detected by a common photodiode, A vehicle alcohol detection device that detects an alcohol component in a vehicle based on alcohol concentration data obtained by subtracting light reception amount data of an alcohol absorption wavelength from light reception amount data of a reference wavelength is known (Patent Document 2). In this in-vehicle alcohol detection device, the alcohol component in the vehicle of the traveling vehicle is detected remotely while the vehicle is running.
JP2003-146107A JP 2000-230900 A

  However, the above Patent Document 1 does not describe a specific method for detecting the drinking level, and therefore has a problem that the drinking level cannot be determined. Moreover, in the technique of the said patent document 2, since the alcohol contained in the air of the whole vehicle interior is detected and the driver's and a passenger's drinking state cannot be distinguished, the driver's drinking state used as a judgment object is determined. There is a problem that it cannot be determined with high accuracy.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a drinking determination device and a program that can accurately determine a drinking state without touching a determination target person.

  In order to achieve the above object, a drinking determination apparatus according to a first invention includes an imaging means having sensitivity in a wavelength region including at least a part of a near-infrared light wavelength region, and a determination target person imaged by the imaging device. A luminance of a determination target image representing a predetermined portion where light absorption characteristics due to alcohol appear, and an image where the light absorption characteristics do not appear or the determination target image is different from the light absorption characteristics, and A feature amount calculating means for calculating a feature amount representing an amount of light absorbed by the alcohol contained in the predetermined portion based on a luminance of a reference image representing the predetermined portion; and the feature calculated by the feature amount calculating portion. And determining means for determining the drinking state of the determination subject based on the amount.

  According to a second aspect of the invention, there is provided a program for causing a computer to display light absorption characteristics due to alcohol of a determination target person imaged by an imaging means having sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region. The brightness of a determination target image representing a part, and the brightness of a reference image representing the predetermined part, which is an image in which the light absorption characteristic differs from an image in which the light absorption characteristic does not appear or the determination target image Based on the feature amount calculating means for calculating the amount of light absorbed by the alcohol contained in the predetermined portion, and based on the feature amount calculated by the feature amount calculating means, It is a program for functioning as a determination means for determining the drinking level.

  According to the first invention and the second invention, the person to be determined is imaged by the imaging means having sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region. Then, the luminance of the determination target image representing the predetermined portion where the light absorption characteristic due to the alcohol of the determination target person imaged by the imaging unit is obtained, and the image or the determination target image that does not exhibit the light absorption characteristic is light The luminance of a reference image representing a predetermined part is acquired, and the alcohol contained in the predetermined part is obtained by the feature amount calculation unit based on the luminance of the determination target image and the reference image. A feature amount representing the amount of light absorbed by is calculated.

  Then, the determination unit determines the drinking state of the determination target person based on the feature amount calculated by the feature amount calculation unit.

  Thus, it is included in the predetermined part of the determination target person calculated based on the luminance of the determination target image representing the predetermined part in which the light absorption characteristic of the determination target person appears and the luminance of the reference image representing the predetermined part. By determining the drinking level of the determination target person based on the feature amount representing the amount of light absorbed by the alcohol, the drinking level can be accurately determined without touching the determination target person.

  The image pickup means according to the first invention has sensitivity to a plurality of different wavelength ranges, wherein at least one wavelength range includes at least a part of the infrared wavelength range, and outputs each image of the plurality of wavelength ranges, The feature amount calculating means includes the luminance of the determination target image in any one of a plurality of wavelength ranges representing the predetermined part of the determination target person imaged by the imaging means, and the plurality of wavelength ranges imaged by the imaging means. The feature amount can be calculated based on the luminance of the reference image in a wavelength region other than the wavelength region of the determination target image. Thus, by comparing the luminance of images having different wavelength ranges, it is possible to calculate a feature amount representing the amount of light absorbed by alcohol at a predetermined portion of the determination target person.

  The feature amount calculating means according to the first invention may calculate the feature amount based on the brightness of the determination target image and the brightness of a reference image in which the light absorption characteristic captured in the past by the imaging means does not appear. it can. Thus, by comparing the luminance of the determination target image with the luminance of the reference image in which the light absorption characteristic captured in the past does not appear, the feature representing the light absorption amount by the alcohol of the predetermined portion of the determination target person The amount can be calculated.

  A drinking determination apparatus according to a third aspect of the present invention is an image pickup unit that picks up an image of a person to be determined and has sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region, and a determination target of an image captured by the image pickup unit. Based on the luminance of a region representing a predetermined portion where light absorption characteristics due to alcohol of the person appear and the luminance of a region representing a reference portion where the light absorption characteristics of the determination subject of the image captured by the imaging means do not appear A feature amount calculating means for calculating a feature amount representing the amount of light absorbed by the alcohol contained in the determination portion; and based on the feature amount calculated by the feature amount calculation means, the drinking state of the determination subject person And determining means for determining whether or not.

  According to a fourth aspect of the present invention, there is provided a program according to an alcohol of a determination target person in an image captured by a computer that images the determination target person and is sensitive to a wavelength range including at least a part of the near-infrared light wavelength range. The determination is based on the luminance of a region representing a predetermined portion where light absorption characteristics appear and the luminance of a region representing a reference portion where the light absorption characteristics of the determination target person of the image captured by the imaging means do not appear. A feature amount calculating means for calculating a feature amount representing the amount of light absorbed by the alcohol contained in the part, and a determination for determining the drinking state of the determination target person based on the feature amount calculated by the feature amount calculating means It is a program for functioning as a means.

  According to the third invention and the fourth invention, the person to be determined is imaged by the imaging means having sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region. And while acquiring the brightness | luminance of the area | region showing the predetermined part where the light absorption characteristic by the alcohol of the judgment subject person of the image imaged by the imaging means appears, the light absorption characteristic of the judgment subject person of the image imaged by the imaging means The luminance of the region representing the reference portion where no appears, and the amount of light absorbed by the alcohol contained in the determination portion based on the luminance of the region representing the predetermined portion and the luminance of the region representing the reference portion by the feature amount calculation means Is calculated.

  Then, the determination unit determines the drinking state of the determination target person based on the feature amount calculated by the feature amount calculation unit.

  Thus, the calculation is based on the luminance of the region representing the predetermined portion where the light absorption characteristic due to the alcohol of the determination target person appears and the luminance of the region representing the reference portion where the light absorption characteristic due to the alcohol of the determination target person does not appear. By determining the drinking state of the determination target person based on the feature amount representing the amount of light absorbed by the alcohol contained in the predetermined part of the determination target person, the drinking state can be accurately determined without touching the determination target person. Can be determined.

  The reference site according to the third invention can be hair or eyebrows.

  The feature amount representing the amount of light absorbed by the alcohol can be a relative value of luminance.

  The drinking determination apparatus may further include an illuminating unit that irradiates the determination target person with light in a wavelength region including at least a part of the near-infrared light wavelength region.

  In addition, the predetermined portion where the light absorption characteristic by the alcohol appears may be at least one of lips, eyes, upper eyelids, lower eyelids, ears, neck, and chest. Thereby, it is possible to accurately calculate the feature amount representing the amount of light absorbed by the alcohol contained in the predetermined portion.

  Moreover, said wavelength range can be made into the wavelength range containing at least 1 of 1200-1300nm, 1650-1750nm, and 2300-2400nm. Thereby, it is possible to accurately calculate the feature amount representing the amount of light absorbed by the alcohol contained in the predetermined portion.

  As described above, according to the drinking determination device and the program of the present invention, the drinking state of the determination target person is determined based on the feature amount representing the amount of light absorbed by the alcohol contained in the predetermined part of the determination target person. Thereby, the effect that the drinking state can be accurately determined without touching the determination target person can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, a case where the present invention is applied to a drinking determination device that determines a drinking state of a vehicle driver will be described as an example.

  As shown in FIG. 1, the drinking determination apparatus 10 according to the first embodiment illuminates the face of the driver who is the determination target with light in a specific wavelength range of the near-infrared light wavelength range. 12 and an imaging device 14 that includes a light receiving device that is sensitive to light in a specific wavelength range irradiated by the illumination device 12 and acquires an image of a subject including a driver's face as a captured image.

  The illuminating device 12 irradiates the driver's face with light in a wavelength range of 1650 to 1750 nm, for example, as light in a specific wavelength range in the near-infrared light wavelength range. The illumination device 12 is controlled to irradiate near infrared light in accordance with the shutter of the imaging device 14.

  The imaging device 14 includes a light receiving device (not shown) having sensitivity to light in a specific wavelength range of 1650 to 1750 nm and a light receiving device (not shown) having sensitivity to light in a visible light range different from the specific wavelength range. Then, a captured image in a specific wavelength region and a captured image in the visible light region, which have different light absorption characteristics due to ethanol as an alcohol, are output. Note that the imaging device 14 may shoot images in a plurality of wavelength regions (specific wavelength region and visible light region) at once using a prism or a half mirror like a 3CCD camera, or by switching filters temporally. You may shoot. Different filters may be arranged for each pixel as in a single-plate color camera.

  The imaging device 14 also includes an A / D converter (not shown) that A / D converts an image signal generated by the light receiving device, and an image memory for temporarily storing the A / D converted image signal. (Not shown). In addition, regarding the wavelength range in which the two light receiving devices have sensitivity, if one wavelength range includes the near-infrared light wavelength range and the main wavelength range is different, a part of the wavelength range overlaps. Also good.

  Since the light in the near-infrared wavelength region enters not only the surface of the skin but also the inside of the skin and is reflected in the skin, the light in the specific wavelength region in the near-infrared wavelength region irradiated from the illumination device 12 The light is reflected inside the skin of the driver's face, and the reflected light is received by the light receiving device of the imaging device 14. On the other hand, since the light in the visible light region is reflected on the surface of the skin, the light in the visible light region reflected on the skin surface of the driver's face is received by the light receiving device of the imaging device 14.

  In addition, the drinking determination device 10 includes a computer 16 that stores a determination program for realizing a drinking determination processing routine for determining a driver's drinking state based on two captured images output from the imaging device 14, and And a display device 18 for displaying a processing result in the computer 16.

  The computer 16 includes a CPU, a ROM that stores a determination program of a drinking determination processing routine that will be described later, a RAM that stores data, and a bus that connects these. If the computer 16 is described in terms of functional blocks divided for each function realizing means determined based on hardware and software, as shown in FIG. 1, two captured images that are grayscale images output from the imaging device 14 are shown. A region representing a specific part where light absorption characteristics due to ethanol appear when ethanol is included is detected from each of the two imaged images input by the image input unit 20 and the image input unit 20. A feature amount that calculates a feature amount that represents the amount of light absorbed by ethanol contained in the specific portion necessary for drinking determination, from the luminance value of the specific portion detection unit 22 and a region that represents each specific portion of the two captured images. The calculation part 24 and the drinking determination part 26 which determines a driver | operator's drinking state based on the calculated feature-value are provided.

The specific part detection unit 22 detects a region representing the specific part from the captured image by a conventional image processing technique such as pattern matching. The specific site refers to a portion where the subcutaneous fat is thin and the distance from the skin surface to the blood vessel is short. Specifically, the specific site detection unit 22 uses the eyes, upper and lower eyelids, lips, and ears as shown in FIG. An area representing the neck and chest is detected. Any one of these areas may be detected, or an area representing each of all the parts may be detected. The feature amount calculation unit 24 absorbs light by ethanol contained in the specific part. As a feature quantity representing the quantity, a ratio of luminance values of areas representing specific parts of the two captured images is calculated. In addition, when the area | region showing each of several specific site | parts is detected by the specific site | part detection part 22, the feature-value is calculated similarly about each site | part.

  Based on the calculated feature value, the drinking determination unit 26 determines whether or not the specific part contains a predetermined amount or more of ethanol. When the above ethanol is not included, it is determined as a non-drinking state.

  The display device 18 displays the determination result by the computer 16 on the output screen, and transmits the determination result to the driver who is the determination target.

  Here, the principle of determining the drinking level will be described. For example, consider acquiring a captured image in a wavelength region A in which light absorption characteristics due to ethanol are seen and a captured image in a wavelength region B in which light absorption properties due to ethanol are not observed. At this time, if the driver who is the subject is in a drinking state, the brightness of the captured image in the wavelength region A is smaller (appears darker) than that in the case of not being in the drinking state. Such a change does not appear between the drinking state and the non-drinking state in the luminance value of the captured image in the wavelength band B. Therefore, the ratio of the brightness value of the captured image in the wavelength range A to the brightness value of the captured image in the wavelength range B is calculated, and if the calculated ratio is small, it is determined that the driver is in a drinking state. If the calculated ratio is large, it is determined that the driver is not in a drinking state.

  Next, the operation of the drinking determination apparatus 10 according to the first embodiment will be described.

  First, when the imaging device 14 is directed toward the driver's face and two captured images representing the driver's face are captured by the imaging device 14, a drinking determination processing routine shown in FIG. The

  First, in step 100, a captured image in a specific wavelength region in the near-infrared light wavelength region is acquired as a determination target image from the imaging device 14, and a captured image in the visible light region is acquired as a reference image. In step 102, A region representing the specific part is detected from the captured image in the specific wavelength range of the near-infrared light wavelength range, and a region representing the specific part is detected from the captured image in the visible light range.

  In step 104, based on the region representing the specific part of the captured image in the specific wavelength region of the near-infrared light wavelength region detected in step 102 and the region representing the specific part of the captured image in the visible light region. Then, the ratio of the luminance value of the region representing the specific part of the captured image in the specific wavelength region to the luminance value of the region representing the specific part of the captured image in the visible light region is calculated as a feature amount representing the amount of light absorption, step 106 Then, it is determined whether or not the feature amount calculated in step 104 is less than a predetermined threshold value. As for the threshold value, the luminance value of the specific part of the captured image in the specific wavelength region of the near-infrared light wavelength region with respect to the luminance value of the specific region of the captured image of the visible light region in the drinking state is statistically or experimentally. And a threshold value may be set in advance based on the obtained ratio.

  If the calculated feature amount is less than the threshold value in step 106, a message indicating that the driver is in a drinking state is displayed on the display device 18 in step 108, and a drinking determination processing routine is performed. On the other hand, if the calculated feature amount is equal to or greater than the threshold value, a message indicating that the driver is not in the drinking state is displayed on the display device 18 in step 110, and the drinking determination process is performed. End the routine.

  As described above, according to the drinking determination apparatus according to the first embodiment, a region representing a specific portion where light absorption characteristics due to ethanol appear in a captured image in a specific wavelength region of the near-infrared light wavelength region. A driver's drinking state based on a feature amount representing the amount of light absorbed by ethanol, which is calculated based on the brightness of the vehicle and the brightness of a region representing a specific part of a captured image in the visible light range Thus, it is possible to accurately determine the drinking level without touching the driver.

  In addition, by using a captured image in a specific wavelength region in the near-infrared light wavelength region as a determination target image, it is possible to accurately calculate a feature value representing the amount of light absorbed by ethanol contained in the specific region.

  In addition, in the near-infrared light wavelength region and in a specific wavelength region where the absorption characteristics due to ethanol appear, the driver's face is imaged, and the eyes, ears, lips, neck, It is possible to detect the phenomenon that the brightness of the image (light reflectivity of the target area) decreases due to light absorption by ethanol in the blood at the chest, and determine the driver's drinking state without contact.

  In the above embodiment, the case where the ratio of luminance values is calculated as a feature amount has been described as an example. However, the present invention is not limited to this, and a relative value of luminance values may be calculated as a feature amount. For example, the difference between the luminance value of the specific region of the reference image and the luminance value of the specific region of the determination target image may be calculated as the feature amount. Further, the relative reflectance may be calculated as the feature amount based on the luminance value of the specific region of the reference image and the luminance value of the specific region of the determination target image.

  Moreover, although the case where the determination result is displayed on the display device and the determination result is transmitted to the driver has been described as an example, the present invention is not limited to this, and the determination result is transmitted to the driver through voice. Also good. Further, control such as engine stop may be performed based on the determination result.

  Moreover, although the case where the wavelength range of the determination target image is the near infrared light wavelength range and the wavelength range of the reference image is the visible light range has been described as an example, the present invention is not limited to this. The wavelength range of the image is a wavelength range including at least one of the near infrared light wavelength range of 1200 to 1300 nm, 1650 to 1750 nm, and 2300 to 2400 nm, and the wavelength range of the reference image is the wavelength range of the determination target image Different from the above. In addition, the wavelength range of the determination target image may be a wavelength range of the near infrared wavelength range as long as it is different from the wavelength range of the reference image.

  Next, a second embodiment will be described. In addition, about the part which becomes the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the second embodiment, the ratio of the luminance value of the region representing the reference region where the light absorption characteristic due to ethanol does not appear and the luminance value of the region representing the specific region where the light absorption property appears is expressed as the amount of light absorption. This is different from the first embodiment in that it is calculated as a feature value to be represented.

  As shown in FIG. 4, the drinking determination apparatus 210 according to the second embodiment includes the illumination device 12 and a light receiving device (not shown) having sensitivity to light in a specific wavelength range of 1650 to 1750 nm, and An imaging device 214 that outputs a captured image in a specific wavelength range, and a determination program for realizing a drinking determination processing routine that determines a driver's drinking state based on one captured image output from the imaging device 214 A stored computer 216 and a display device 18 are provided.

  The computer 216 receives an image input unit 220 that inputs one captured image that is a grayscale image output from the imaging device 214, and absorbs light from ethanol from one captured image input by the image input unit 220. A specific part detection unit 22 for detecting a region representing a specific part where the light appears, and a reference for detecting a region representing a reference part where the light absorption characteristic of ethanol does not appear from one captured image input by the image input unit 220 A feature amount representing the amount of light absorbed by ethanol contained in the specific portion necessary for drinking determination is determined from the portion detection unit 222 and the luminance value of the region representing the specific portion of the captured image and the luminance value of the region representing the reference portion. A feature quantity calculation unit 224 to calculate and a drinking determination unit 26 are provided.

  The reference part detection unit 222 detects a region representing the reference part from the captured image by a conventional image processing technique such as pattern matching. The reference part where the light absorption characteristic by ethanol does not appear is a part not affected by the presence of ethanol, for example, hair or eyebrows in which blood flow does not flow as shown in FIG.

  The feature amount calculation unit 224 calculates the ratio of the luminance value of the region representing the specific portion to the luminance value of the region representing the reference portion of the captured image as the feature amount representing the amount of light absorbed by ethanol contained in the specific portion. . In addition, when the area | region showing each of several specific site | parts is detected by the specific site | part detection part 22, the feature-value is calculated similarly about each site | part.

  Here, the principle of determining the drinking level will be described. For example, from a captured image in a wavelength region A in which light absorption characteristics due to ethanol can be seen, an area representing a specific part where the light absorption characteristic due to ethanol appears and an area representing a reference part where the light absorption characteristic due to ethanol does not appear Think about getting. At this time, if the driver who is the subject is in a drinking state, the luminance of the specific part is smaller (appears darker) than in the case where the driver is not in a drinking state. Regarding the luminance value of the region representing the reference part, such a change does not appear between the drinking state and the non-drinking state. Therefore, the ratio of the luminance value of the image of the region representing the specific region to the luminance value of the image of the region representing the reference region is calculated, and if the calculated ratio is small, the driver is in a drinking state. When the calculated ratio is large, it is determined that the driver is not in a drinking state.

  Next, a drinking determination processing routine according to the second embodiment will be described with reference to FIG. In addition, about the process similar to 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  First, in step 250, a captured image in a specific wavelength region in the near-infrared light wavelength region is acquired from the imaging device 214. In step 252, a region representing a specific part is detected from the captured image acquired in step 250. In step 254, a region representing the reference region is detected from the captured image.

  In step 256, based on the region representing the specific part of the captured image detected in step 252 and the region representing the reference part of the captured image detected in step 254, the luminance of the region representing the reference part The ratio of the luminance value of the region representing the specific part to the value is calculated as a feature amount representing the amount of light absorption. In step 106, the feature amount calculated in step 256 is less than a predetermined threshold value. It is determined whether or not there is. As for the threshold, statistically or experimentally, the ratio of the luminance value of the specific part to the luminance value of the reference part of the captured image in the specific wavelength region of the near-infrared light wavelength region in the drinking state is obtained, A threshold value may be set in advance based on the obtained ratio.

  If the calculated feature amount is less than the threshold value in step 106, a message indicating that the driver is in a drinking state is displayed on the display device 18 in step 108, and a drinking determination processing routine is performed. On the other hand, if the calculated feature amount is equal to or greater than the threshold value, a message indicating that the driver is not in the drinking state is displayed on the display device 18 in step 110, and the drinking determination process is performed. End the routine.

  As described above, according to the drinking determination apparatus according to the second embodiment, the specific part where the light absorption characteristic due to ethanol appears in the captured image in the specific wavelength region of the near-infrared light wavelength region in which the driver is imaged. Is calculated based on the luminance of the region representing the vehicle and the luminance of the region representing the reference region where the light absorption characteristic of the driver by ethanol does not appear, and the amount of light absorbed by ethanol contained in the specific region of the driver is calculated. By determining the driver's drinking level based on the feature amount to be expressed, the drinking level can be accurately determined without touching the driver.

  Next, a third embodiment will be described. In addition, about the part which becomes the same structure as 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the third embodiment, the feature amount is calculated based on the luminance value of the region representing the specific part of the captured image captured in the past and the luminance value representing the specific part of the captured image to be determined. The point is different from the first embodiment and the second embodiment.

  As shown in FIG. 7, the drinking determination device 310 according to the third embodiment is based on the lighting device 12, the imaging device 214, and one captured image output from the imaging device 214. The computer 316 which stored the determination program for implement | achieving the drinking determination processing routine which determines a drinking state, and the display apparatus 18 are provided.

  The computer 316 stores an image input unit 220, a specific part detection unit 22, and a reference that stores the luminance of a region representing a specific part of a reference image in which light absorption characteristics by ethanol imaged in the past by the imaging device 214 are not seen. The amount of light absorbed by ethanol contained in the specific part necessary for drinking determination is expressed from the image storage unit 322 and the luminance value of the area representing the specific part of the captured image and the luminance value of the area representing the specific part of the reference image. A feature amount calculation unit 324 that calculates a feature amount and a drinking determination unit 26 are provided.

  The reference image storage unit 322 stores a luminance value of an area representing a specific portion of the reference image in which light absorption characteristics by ethanol obtained by imaging the driver who is not in a drinking state in the past with the imaging device 214 is not seen. ing. A driver who is not in a drunk state is imaged in the past by the imaging device 214, a region representing a specific part is detected from the captured reference image, and a luminance value of the detected region representing the specific part is obtained as a reference image storage unit Stored in 322. In addition, for each of a plurality of reference images in which absorption characteristics of light imaged in the past are not found, a luminance value of an area representing a specific part is obtained, and a luminance value to be stored (for example, luminance) is calculated from the obtained luminance value distribution. An average value) may be obtained. When a plurality of specific parts are detected by the specific part detection unit 22, the luminance value for each specific part region is stored in the reference image storage unit 322.

  The feature amount calculation unit 324 calculates a ratio of the luminance value of the specific portion of the determination target captured image to the luminance value of the specific portion of the stored reference image as a feature amount indicating the amount of light absorbed by ethanol contained in the specific portion. calculate. When a plurality of specific parts are detected by the specific part detection unit 22, a ratio of luminance values is calculated for each specific part.

  Here, the principle of determining the drinking level will be described. For example, from the captured image of the determination target of the wavelength region A in which the light absorption characteristics of ethanol are seen, the region representing the specific part where the light absorption characteristics appear, and the captured image of the wavelength region A, and Consider obtaining a region representing a specific part from a reference image, which is an image in which the light absorption characteristic of ethanol is not observed. At this time, if the driver, who is the subject, is in a drinking state, the luminance of a specific part of the determination target captured image is smaller than that in the drinking state (appears darker). On the other hand, such a change does not appear with respect to the luminance value of the specific part of the reference image. Therefore, when the ratio of the luminance value of the image of the region representing the specific part of the image to be determined to the luminance value of the image of the region representing the specific part of the reference image is calculated, and the calculated ratio is small Is determined that the driver is in a drunk state, and if the calculated ratio is large, it is determined that the driver is not in a drunk state.

  Next, a drinking determination processing routine according to the third embodiment will be described with reference to FIG. In addition, about the process similar to 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  First, in step 250, a captured image in a specific wavelength region in the near-infrared light wavelength region is acquired as a determination target image from the imaging device 214. In step 252, a specific part is represented from the captured image acquired in step 250. A region is detected, and in step 350, the luminance value of the region representing the specific part of the reference image is acquired from the reference image storage unit 322.

  In step 352, based on the luminance value of the area representing the specific part of the captured image detected in step 252 and the luminance value of the area representing the specific part of the reference image acquired in step 350, the reference The ratio of the luminance value of the region representing the specific part of the captured image to be determined to the luminance value of the region representing the specific part of the image is calculated as a feature amount representing the amount of light absorption. In step 106, the ratio is calculated in step 352 above. It is determined whether the determined feature amount is less than a predetermined threshold value. Note that the threshold value is specified statistically or experimentally by specifying a captured image in a specific wavelength region in the drinking state relative to the luminance value of a specific region in the specific wavelength region in the near-infrared light wavelength region in the non-drinking state. A ratio of luminance values of the parts may be obtained, and a threshold value may be set in advance based on the obtained ratio.

  If the calculated feature amount is less than the threshold value in step 106, a message indicating that the driver is in a drinking state is displayed on the display device 18 in step 108, and a drinking determination processing routine is performed. On the other hand, if the calculated feature amount is equal to or greater than the threshold value, a message indicating that the driver is not in the drinking state is displayed on the display device 18 in step 110, and the drinking determination process is performed. End the routine.

  As described above, according to the drinking determination apparatus according to the third embodiment, the specific portion where the light absorption characteristic due to ethanol appears in the determination target image in the specific wavelength region of the near-infrared light wavelength region is represented. Based on the feature amount representing the amount of light absorbed by ethanol, which is calculated based on the luminance of the region and the luminance of the region representing the specific part of the reference image in which the light absorption characteristics captured in the past do not appear By determining the driver's drinking level, the drinking level can be accurately determined without touching the driver.

  In the above-described embodiment, the case where the luminance value of the specific part of the non-drinking state captured image captured in the past is stored as an example is described. You may memorize | store the luminance value of a specific site | part.

  Moreover, although the case where the brightness | luminance value of the area | region showing the specific site | part of a reference | standard image was memorize | stored was demonstrated to the example, it is not limited to this, You may memorize | store a reference | standard image itself. In this case, when the feature amount is obtained, a region representing the specific part is detected from the reference image, and the luminance value of the region representing the specific part of the reference image may be acquired.

  Next, a fourth embodiment will be described. In addition, about the part which becomes the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the fourth embodiment, a feature amount distribution calculated from a captured image captured in the past is compared with a feature amount calculated from a captured image to be determined. Is different.

  As illustrated in FIG. 9, the computer 416 of the drinking determination apparatus 410 according to the fourth embodiment includes an image input unit 20, a specific part detection unit 22, a feature amount calculation unit 24, and a captured image captured in the past. Based on the feature quantity distribution storage unit 424 that stores the feature quantity distribution calculated from the feature quantity and the feature quantity distribution calculated and the feature quantity distribution stored in the feature quantity distribution storage unit 424, the driver's drinking state is determined. And a drinking determination unit 426.

  A feature amount representing the amount of light absorption calculated from each of a plurality of captured images obtained by previously imaging a driver in a drunk state by the imaging device 14 is collected, the collected feature amount is analyzed, and a feature amount in a drunk state is collected. , And the obtained feature quantity distribution is stored in the feature quantity distribution storage unit 424. Further, the distribution of the feature amount is obtained for each captured time zone, and the distribution of the feature amount is stored in the feature amount distribution storage unit 424 for each time zone. Note that the feature amount distribution may be stored for each personal data in consideration of individual differences among drivers.

  The drinking determination unit 426 acquires the distribution of the feature amount with respect to the time zone at the time of determination from the feature amount distribution storage unit 424, and the current feature amount calculated from the captured image of the determination target is obtained from the distribution of the acquired feature amount. Drinking judgment is performed by verifying whether it is off.

  In the drinking determination processing routine according to the fourth embodiment, the region representing the specific part of the captured image in the specific wavelength region of the near-infrared light wavelength region detected by the specific region detector 22 and the captured image in the visible light region Based on the region representing the specific part, the ratio of the luminance values of the region representing the specific part is calculated as a feature amount representing the light absorption amount. Then, the distribution of the feature amount in the drinking state with respect to the current time zone is acquired from the feature amount distribution storage unit 424. Based on how far the calculated feature amount deviates from the acquired distribution of the feature amount, the driver It is determined whether or not the person is currently in a drinking state, a message indicating the determination result is displayed on the display device 18, and the drinking determination processing routine is terminated.

  In this way, the drinking level is determined accurately in order to determine the drinking level by comparing the distribution of the characteristic amount obtained from the captured image of the drinking level captured in the past with the characteristic amount obtained from the determination target image. can do.

  In addition, since the distribution of the feature amount for each time zone is stored, it is possible to make a determination corresponding to an environment that changes due to a change in illumination or a living body according to the time zone, and to determine the drinking level with higher accuracy. .

  In the above-described embodiment, the case where the distribution of the feature amount is stored has been described as an example. However, the present invention is not limited to this, and is obtained from the distribution of the feature amount obtained from the captured image captured in the past. You may make it memorize | store the threshold value regarding the feature-value performed.

  In addition, when there are a plurality of specific parts, a distribution of feature values indicating the feature values of each specific part may be stored.

  In addition, the feature amount obtained from the captured image captured in the past, not the distribution of the feature amount, is stored, and the feature amount obtained from the determination target image is compared with the stored feature amount, and the drinking state May be determined.

  Moreover, although the case where the distribution of the feature amount obtained from the captured image in the drinking state is stored is described as an example, the present invention is not limited to this, and the distribution of the feature amount obtained from the captured image that is not in the drinking state is stored. You may keep it. In this case, the drinking level may be determined depending on how far the feature amount obtained from the determination target image is away from the stored feature amount distribution.

It is a block diagram which shows the drinking determination apparatus which concerns on the 1st Embodiment of this invention. It is an image figure which shows the specific example of a specific site | part. It is a flowchart which shows the content of the drinking determination processing routine in the drinking determination apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the drinking determination apparatus which concerns on the 2nd Embodiment of this invention. It is an image figure which shows the specific example of a reference | standard part. It is a flowchart which shows the content of the drinking determination processing routine in the drinking determination apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the drinking determination apparatus which concerns on the 3rd Embodiment of this invention. It is a flowchart which shows the content of the drinking determination processing routine in the drinking determination apparatus which concerns on the 3rd Embodiment of this invention. It is a block diagram which shows the drinking determination apparatus which concerns on the 4th Embodiment of this invention.

Explanation of symbols

10, 210, 310, 410 Drinking determination device 12 Illumination device 14, 214 Imaging device 16, 216, 316, 416 Computer 18 Display device 20, 220 Image input unit 22 Specific site detection unit 24, 224, 324 Feature amount calculation unit 26 426 Drinking determination unit 222 Reference region detection unit 322 Reference image storage unit 424 Feature quantity distribution storage unit 426 Drinking determination unit

Claims (11)

Imaging means having sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region;
The luminance of the determination target image representing the predetermined portion where the light absorption characteristic due to the alcohol of the determination target person captured by the imaging means appears, and the image where the light absorption characteristic does not appear or the determination target image is the light A feature amount calculating means for calculating a feature amount representing an amount of light absorbed by the alcohol contained in the predetermined portion, based on the brightness of a reference image representing the predetermined portion, the images having different absorption characteristics;
A determination unit that determines a drinking state of the determination target person based on the feature amount calculated by the feature amount calculation unit;
Drinking judgment device including The imaging means has sensitivity to each of a plurality of different wavelength ranges in which at least one wavelength range includes at least a part of the infrared light wavelength range, and outputs an image of each of the plurality of wavelength ranges,
The feature amount calculating means captures the brightness of the determination target image in any one of the plurality of wavelength bands representing the predetermined part of the determination target person imaged by the imaging means, and the imaging means The drinking determination apparatus according to claim 1, wherein the feature amount is calculated based on luminance of the reference image in a wavelength region other than the determination target image among the plurality of wavelength regions.   The feature amount calculation unit calculates the feature amount based on a luminance of the determination target image and a luminance of the reference image in which an absorption characteristic of the light imaged in the past by the imaging unit does not appear. 1. A drinking determination apparatus according to 1. An imaging means for imaging a person to be judged and having sensitivity in a wavelength region including at least a part of the near-infrared light wavelength region;
Luminance of a region representing a predetermined part where light absorption characteristics due to alcohol of the determination target person appear in the image captured by the imaging means, and the light absorption characteristics of the determination target person of the image captured by the imaging means. Feature amount calculating means for calculating a feature amount representing the amount of light absorbed by the alcohol contained in the determination portion based on the luminance of the region representing the reference portion that does not appear;
A determination unit that determines a drinking state of the determination target person based on the feature amount calculated by the feature amount calculation unit;
Drinking judgment device including   The drinking determination apparatus according to claim 4, wherein the reference portion is hair or eyebrows.   The drinking determination apparatus according to any one of claims 1 to 5, wherein the feature amount is a relative value of luminance.   The drinking determination apparatus according to any one of claims 1 to 6, further comprising an illuminating unit that irradiates the determination subject with light in a wavelength range including at least a part of the near-infrared light wavelength range.   The drinking determination apparatus according to any one of claims 1 to 7, wherein the predetermined part is at least one of lips, eyes, upper eyelids, lower eyelids, ears, neck, and chest.   The drinking determination apparatus according to any one of claims 1 to 8, wherein the wavelength range is a wavelength range including at least one of 1200 to 1300 nm, 1650 to 1750 nm, and 2300 to 2400 nm. Computer
The luminance of the determination target image representing the predetermined portion where the absorption characteristic of light by alcohol of the determination target imaged by the imaging means having sensitivity in the wavelength range including at least a part of the near infrared light wavelength range, and the light absorption Based on the brightness of the reference image representing the predetermined part, the light of the alcohol due to the alcohol contained in the predetermined part is different from the image in which the characteristic does not appear or the determination target image. A feature amount calculation means for calculating a feature amount representing an absorption amount, and a program for functioning as a determination means for determining the drinking state of the determination subject based on the feature amount calculated by the feature amount calculation means. Computer
An area representing a predetermined region where the determination target person's alcohol absorbs light in an image captured by the imaging means having sensitivity in a wavelength range including at least a part of the near-infrared light wavelength range. The amount of light absorbed by alcohol contained in the determination portion is represented based on the luminance and the luminance of the region representing the reference portion where the light absorption characteristic of the determination target person does not appear in the image captured by the imaging means. A feature amount calculating means for calculating a feature amount, and a program for functioning as a determination means for determining a drinking state of the determination target person based on the feature amount calculated by the feature amount calculation means.

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