JP5505693B2 - DETECTING DEVICE, DETECTING METHOD, PROGRAM, AND ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to a detection device, a detection method, a program, and an electronic device, and more particularly, for example, a detection device, a detection method, a program, and an electronic device suitable for detecting the shape of a human hand from a captured image Regarding equipment.

  2. Description of the Related Art Conventionally, for example, there is a skin recognition system that detects (recognizes) a skin region representing human skin from a captured image obtained by imaging a subject (see, for example, Non-Patent Document 1).

  FIG. 1 shows a configuration example of a conventional skin recognition system 1.

  The skin recognition system 1 includes a light emitting device 21, a camera 22, and an information processing device 23.

The light emitting device 21 includes LEDs (light emitting diodes) 21a ₁ and 21a ₂ (represented by two black circles) that emit (emit) light of wavelength λ1 (for example, near infrared light of 870 [nm]), and wavelength λ1. composed of light of different wavelengths .lambda.2 (e.g., near infrared 950 [nm]) (respectively indicated by two circles) LED 21b ₁ and 21b ₂ is irradiated with the.

  The combination of wavelengths λ1 and λ2 is a combination in which, for example, the reflectance when light of wavelength λ1 is irradiated on human skin is greater than the reflectance when light of wavelength λ2 is irradiated on human skin. is there. The combination of the wavelengths λ1 and λ2 is the reflectance when the light of the wavelength λ1 is irradiated on something other than human skin and the reflectance when the light of the wavelength λ2 is irradiated on something other than human skin. The combination is almost unchanged.

Hereinafter, when there is no need to distinguish between the LED 21a ₁ and 21a ₂ are referred to simply as LED 21a and LED 21a ₁ and 21a _2. When there is no need to distinguish between the LED 21b ₁ and 21b ₂ are the LED 21b ₁ and 21b ₂ simply as LED 21b.

  Further, the outputs of the LEDs 21a and 21b are images obtained by the imaging of the camera 22 when a subject having the same reflectance with respect to the wavelengths λ1 and λ2 is irradiated with light of either wavelength λ1 or λ2. Adjustment is made so that the luminance values of corresponding pixels in the image are the same.

  As shown in FIG. 1, the LEDs 21a and the LEDs 21b are arranged in a grid pattern and emit light alternately.

  The camera 22 receives the reflected light of the light having the wavelength λ1 irradiated on the subject, and supplies the first captured image obtained as a result to the information processing device 23. Further, the camera 22 receives the reflected light of the light having the wavelength λ <b> 2 applied to the subject, and supplies the second captured image obtained as a result to the information processing device 23.

  The information processing device 23 controls the light emitting device 21 and the camera 22. In addition, the information processing device 23 calculates a difference absolute value between luminance values of corresponding pixels of the first and second captured images from the camera 22, and performs first imaging based on the calculated difference absolute value. A skin region on the image (or the second captured image) is detected.

[Example of control by conventional information processing apparatus 23]
Next, FIG. 2 shows an example of how the information processing device 23 controls the light emitting device 21 and the camera 22.

  2A to 2E represent the same time.

  For example, in the case of 60 fps (frames per second), the information processing device 23 rises every 16.7 [ms] (= 1/60 [s]) as a VD signal (vertical synchronization signal) as shown in FIG. 2A. A VD signal that generates an edge is generated.

  Then, the information processing device 23 alternately causes the LEDs 21a and 21b to emit light at a light emission time (irradiation time) of 16.7 [ms] every time a rising edge occurs in the generated VD signal.

  That is, for example, as shown in FIG. 2B, the information processing device 23 starts the light emission of the LED 21a at each timing when an odd-numbered rising edge occurs among a plurality of rising edges generated in the generated VD signal, Light emission ends 16.7 [ms] after the start.

  Further, as shown in FIG. 2C, the information processing device 23 starts the light emission of the LED 21b at every timing when even-numbered rising edges occur among the plurality of rising edges generated in the generated VD signal. The light emission ends after 16.7 [ms].

  Furthermore, the information processing device 23 causes the camera 22 to be exposed with an exposure time of 16.7 [ms] at each timing when a plurality of rising edges appear in the generated VD signal. That is, for example, as illustrated in FIG. 2D, the information processing apparatus 23 starts exposure at each timing when a plurality of rising edges generated in the VD signal occur, and ends the exposure after 16.7 [ms] from the start of exposure.

  As a result, as shown in FIG. 2E, the camera 22 receives the reflected light of the light irradiated to the subject with an exposure time of 16.7 [ms] according to the timing at which a plurality of rising edges generated in the VD signal occur. The electric charge corresponding to the received reflected light is accumulated.

That is, for example, the camera 22 receives reflected light (reflected light having a wavelength λ1) emitted from the LED 21a to the subject with an exposure time of 16.7 [ms], and accumulates charges. Then, as shown in FIG. 2E, the camera 22 generates a first captured image including pixels having a luminance value α ₁ ′ corresponding to the charge amount α ₁ of the accumulated charge, and the information processing apparatus 23 To supply.

Further, for example, the camera 22 receives reflected light (reflected light having a wavelength λ2) emitted from the LED 21b to the subject with an exposure time of 16.7 [ms], and accumulates charges. Then, as shown in FIG. 2E, the camera 22 generates a second captured image including pixels having a luminance value β ₁ ′ corresponding to the accumulated charge amount β ₁ , and the information processing apparatus 23 To supply.

  Based on the first and second captured images from the camera 22, the information processing apparatus 23 detects a skin region using spectral reflection characteristics with respect to human skin.

  That is, as described above, in the combination of wavelengths λ1 and λ2, the reflectance when light of wavelength λ1 is irradiated on human skin is larger than the reflectance when light of wavelength λ2 is irradiated on human skin. It is a combination.

Accordingly, when light of wavelength λ1 or λ2 is irradiated on human skin, the charge amount α ₁ accumulated by the reflected light of wavelength λ1 is larger than the charge amount β ₁ accumulated by the reflected light of wavelength λ2. It will be big.

Therefore, the luminance value α ₁ ′ of the pixels constituting the skin area on the first captured image is a relatively large value, and the luminance value β ₁ ′ of the pixels constituting the skin area on the second captured image is compared. Small value. Therefore, the difference absolute value | α ₁ ′ −β ₁ ′ | between the luminance values of the pixels constituting the skin area on the first and second captured images is a relatively large value.

  As described above, the combination of the wavelengths λ1 and λ2 is a combination of the reflectance when the light with the wavelength λ1 is irradiated on the non-human skin and the light with the wavelength λ2 on the non-human skin. This is a combination that is almost the same as the reflectivity of.

Therefore, when the light of wavelength λ1 or λ2 is irradiated to light other than human skin, the charge amount α ₁ accumulated by the reflected light of wavelength λ1 is the charge amount β accumulated by the reflected light of wavelength λ2. _It is almost the same as ₁ .

For this reason, the luminance value α ₁ ′ of the pixels constituting the area other than the skin area on the first captured image and the luminance value β ₁ ′ of the pixels constituting the area other than the skin area on the second captured image are The values are almost the same. Therefore, the absolute difference value | α ₁ ′ −β ₁ ′ | between the luminance values of the pixels constituting the region other than the skin region on the first and second captured images is a relatively small value.

Therefore, in the image processing device 23, for example, when the difference absolute value | α ₁ ′ −β ₁ ′ | is a relatively large value, the pixel corresponding to the difference absolute value | α ₁ ′ −β ₁ ′ | It can be detected as a pixel constituting the skin region.

Yasuhiro Suzuki et al., Electrical Engineering C (Proposal of skin detection method using near-infrared multiband), Japan, 2007, Vol. 127, No. 4

  By the way, the subject is irradiated with light of wavelength λ1 and light of wavelength λ2 from an external light source such as the sun or a fluorescent lamp, in addition to light of wavelength λ1 from LED 21a and light of wavelength λ2 from LED 21b.

In the conventional skin recognition system 1, when the amount of light from the external light source is relatively small, that is, the amount of light from the external light source becomes a difference absolute value | α ₁ ′ −β ₁ ′ | When the amount is small enough not to be affected, the skin region can be detected with high accuracy.

However, when the amount of light from the external light source is relatively large, that is, the amount of light from the external light source is large enough to affect the magnitude of the difference absolute value | α ₁ '−β ₁ ' | In some cases, the skin region cannot be detected.

Specifically, for example, the maximum charge that can be accumulated in any of the charge amounts α ₁ and β ₁ that are accumulated by receiving reflected light from the subject due to light from the external light source When overexposure has occurred, the corresponding luminance values α ₁ ′ and β ₁ ′ are the same value.

In this case, in the conventional skin recognition system 1, for example, a difference absolute value corresponding to the skin region | a difference absolute value corresponding to a region other than the skin area _{| | α 1 '-β 1'} α 1 '-β 1 It becomes the same value as' |, and the skin region cannot be detected based on the magnitude of the absolute difference value | α ₁ '−β ₁ ' |.

  The present invention has been made in view of such a situation, and while maintaining the charge accumulated due to the light from the LED, the charge accumulated due to the external light source is sufficiently reduced. Thus, overexposure is prevented, and a skin area on the captured image is detected with high accuracy.

The detection device or program according to the first aspect of the present invention is a detection device that detects the subject from a captured image obtained by imaging the subject, or a detection that detects the subject from a captured image obtained by imaging the subject. A program for causing a device to function, an irradiation unit that irradiates a subject with light having a predetermined wavelength, and a total charge amount of each pixel accumulated by receiving reflected light from the subject as a pixel value, An imaging unit that generates a captured image obtained by capturing an image of a subject, a detection unit that detects the subject from the captured image, and a control unit that controls the irradiating unit to reflect light of the total charge amount that is irradiated by the irradiating unit. Irradiation control means for irradiating the first charge amount accumulated by receiving light with a predetermined amount of light, and the imaging means are controlled, and the total charge amount is irradiated by external light Second charge amount, the imaging control for receiving the maximum charge amount is possible to accumulate in the first less than obtained difference value by subtracting the amount of charge exposure time accumulated by receiving the reflected light of the And a program for causing the detection apparatus to function as the detection apparatus.

  In the irradiation control means, the first charge amount may be irradiated with a light amount that becomes a charge amount necessary to generate the captured image for detecting the subject.

  A changing means for changing the exposure time of the imaging means can be further provided based on the second charge amount accumulated in the exposure time, and the imaging control means can change the exposure that has been changed. Light can be received in time.

  The irradiation control means can perform irradiation with the same irradiation time as the exposure time.

  The irradiation control means can irradiate within the exposure time with an irradiation time shorter than the exposure time.

  The irradiation control means may perform irradiation with an irradiation time longer than the exposure time including the exposure time.

  The irradiation means includes first output means for irradiating the subject with light having a first wavelength, and second output means for irradiating the subject with light having a second wavelength different from the first wavelength. The imaging means generates a first captured image using a total charge amount of each pixel accumulated by receiving reflected light of the first wavelength as a pixel value, and the second image A second captured image is generated with the total charge amount of each pixel accumulated by receiving reflected light having a wavelength as a pixel value, and the detection unit is configured to generate the second captured image based on the first and second captured images. The subject on one of the first and second captured images can be detected.

  The first and second output means are obtained by irradiating the human skin with the reflectance of the reflected light obtained by irradiating the light of the first wavelength and the light of the second wavelength. It is possible to irradiate light having a wavelength when the difference absolute value with respect to the reflectance of the reflected light is equal to or greater than a predetermined difference threshold value.

  The first and second output means can irradiate infrared rays having different wavelengths.

  One of the first and second output means may emit light having a wavelength of 930 [nm] or more, and the other may emit light having a wavelength of less than 930 [nm].

A detection method according to a first aspect of the present invention is a detection method of a detection device that detects a subject from a captured image in which a total charge amount for each pixel accumulated by receiving reflected light from the subject is a pixel value. The detection apparatus includes an irradiation unit, an imaging unit, a detection unit, an irradiation control unit, and an imaging control unit, and the irradiation control unit irradiates a subject with light having a predetermined wavelength. And controlling the imaging control means to irradiate the reflected light of the light emitted by the irradiating means out of the total charge quantity with a light quantity such that the first charge quantity accumulated becomes a predetermined charge quantity. However, the total charge amount for each pixel accumulated by receiving reflected light from the subject is used as a pixel value to control the imaging unit that generates a captured image of the subject, and out of the total charge amount, Receives and stores reflected light of light irradiated by external light Second amount of charge is the maximum charge amount from the said less than the first difference value obtained by subtracting the amount of charge exposure time is received capable of storing, said detecting means, from the captured image The detection method includes a step of detecting the subject.

According to the first aspect of the present invention, the detection device receives the reflected light of the light irradiated by the irradiating means out of the total charge amount for each pixel received by the reflected light from the subject. The first charge amount accumulated is irradiated with a light amount that becomes a predetermined charge amount, and the second charge amount accumulated by receiving the reflected light of the light irradiated by external light out of the total charge amount , Light is received for an exposure time that is less than the difference value obtained by subtracting the first charge amount from the maximum charge amount that can be accumulated, and the subject is detected from the captured image generated by the light reception.

An electronic device according to a second aspect of the present invention is an electronic device including a detection device that detects the subject from a captured image obtained by imaging the subject, and the detection device emits light of a predetermined wavelength. Irradiating means for irradiating the object, imaging means for generating a picked-up image picked up from the subject with the total charge amount for each pixel accumulated by receiving reflected light from the subject as a pixel value, and the picked-up image from the picked-up image A detecting means for detecting a subject and the irradiating means are controlled, and the first charge amount accumulated by receiving the reflected light of the light irradiated by the irradiating means among the total charge amount is a predetermined charge amount. The irradiation control means for irradiating with the amount of light and the imaging means are controlled, and the second charge amount accumulated by receiving the reflected light of the light irradiated by the external light among the total charge amount is accumulated. From the maximum amount of charge that can be An electronic device comprising an imaging control means for receiving in the exposure becomes less than the difference value obtained by subtracting the first charge amount time.

According to the second aspect of the present invention, the detection device built in the electronic device receives the reflected light from the subject and stores the amount of light irradiated by the irradiating means out of the total charge amount for each pixel accumulated. The first charge amount accumulated by receiving the reflected light is irradiated with a light amount that becomes a predetermined charge amount, and the first charge amount received by the reflected light of the light irradiated by the external light out of the total charge amount is accumulated. 2 is received with an exposure time that is less than the difference value obtained by subtracting the first charge amount from the maximum charge amount that can be accumulated, and the subject is detected from the captured image generated by the received light. The

  According to the present invention, it is possible to prevent overexposure and accurately detect a skin region on a captured image.

It is a block diagram which shows the structural example of the conventional skin recognition system. It is a figure which shows an example of the mode of control by the conventional information processing apparatus. It is a block diagram which shows the structural example of the information processing system which is this Embodiment. It is a figure which shows an example of the spectral reflection characteristic with respect to human skin. It is a figure which shows an example of the outline | summary of the process by the information processing apparatus to which this invention is applied. It is a block diagram which shows the structural example of the information processing apparatus to which this invention is applied. It is a figure which shows an example of the control which a control part performs. It is a figure which shows an example in case skin detection accuracy falls resulting from an external light component. It is a figure which shows an example in the case of adjusting the aperture of a camera and suppressing the electric charge accumulate | stored by an external light component. It is a figure which shows an example in the case of adjusting the shutter speed of a camera and suppressing the electric charge accumulate | stored by an external light component. It is a figure for demonstrating an example of the determination method of exposure time. It is a flowchart for demonstrating the skin detection process which the information processing system to which this invention is applied. It is a block diagram which shows the structural example of a computer.

Hereinafter, modes for carrying out the invention (hereinafter referred to as the present embodiment) will be described. The description will be given in the following order.
1. Embodiment (Example of adjusting the exposure time of a camera and the amount of light by a light emitting device)
2. Modified example

<1. Embodiment>
[Configuration example of information processing system 41]
FIG. 3 shows a configuration example of the information processing system 41 according to the present embodiment.

  The information processing system 41 includes a light emitting device 61, a camera 62, and an information processing device 63.

The light emitting device 61 is constituted by an LED 21a (LED 21a ₁ , LED 21a ₂ ) and an LED 21b (LED 21b ₁ , LED 21b ₂ ), and causes the LED 21a and LED 21b to emit light alternately. Note that the LED 21a and the LED 21b constituting the light emitting device 61 are the same as the LED 21a and the LED 21b constituting the light emitting device 21 of FIG. 1, and therefore, the same reference numerals are given and the description thereof is omitted.

  The combination of wavelengths λ1 and λ2 is a combination in which, for example, the reflectance when light of wavelength λ1 is irradiated on human skin is greater than the reflectance when light of wavelength λ2 is irradiated on human skin. is there. The combination of the wavelengths λ1 and λ2 is the reflectance when the light of the wavelength λ1 is irradiated on something other than human skin and the reflectance when the light of the wavelength λ2 is irradiated on something other than human skin. The combination is almost unchanged. This combination is determined based on spectral reflection characteristics with respect to human skin, which will be described later with reference to FIG.

  Further, the output of the LED 21a and the LED 21b is an image obtained by imaging of the camera 62 when the object having the same reflectance with respect to the wavelengths λ1 and λ2 is irradiated with light of either wavelength λ1 or λ2. Adjustment is performed according to the exposure time of the camera 62 so that the luminance values of corresponding pixels in the image are the same.

  Further, a diffusion plate 61a for uniformly diffusing light emitted from the LEDs 21a and 21b is provided on the front surfaces of the LEDs 21a and 21b. As a result, the subject is evenly irradiated with light having the wavelength λ1 and light having the wavelength λ2.

  The camera 62 has a lens used for imaging a subject such as a user, and the front surface of the lens is covered with a visible light cut filter 62a that blocks visible light.

  Therefore, visible light is not incident on the camera 62, and reflected light having a wavelength λ1 or reflected light having a wavelength λ2 from the subject is incident as invisible light.

  That is, for example, the camera 62 receives an irradiation light component of the wavelength λ1 and an external light component of the wavelength λ1 as reflected light of the wavelength λ1 from the subject, and the first captured image obtained as a result is processed into the information processing device 63.

  Note that the irradiation light component of wavelength λ1 refers to the reflected light of the light of wavelength λ1 that is irradiated onto the subject by the LED 21a. The external light component having the wavelength λ1 refers to reflected light of the light having the wavelength λ1 that is emitted to the subject by the external light source.

  Further, for example, the camera 62 receives an irradiation light component having a wavelength λ2 and an external light component having a wavelength λ2 as reflected light having a wavelength λ2 from the subject, and a second captured image obtained as a result is processed as an information processing device. 63.

  Note that the irradiation light component with the wavelength λ2 refers to the reflected light of the light with the wavelength λ2 applied to the subject by the LED 21b. The external light component having the wavelength λ2 refers to reflected light of the light having the wavelength λ2 that is emitted to the subject by the external light source.

  Further, when both the LED 21a and the LED 21b are turned off, the camera 62 receives only the external light component of the wavelength λ1, and supplies the third captured image obtained as a result to the information processing device 63.

  Note that when the first and third captured images are generated by the camera 62 using a filter that allows only a predetermined wavelength to pass, in addition to the visible light cut filter 62a, only light having a wavelength λ1 is incident on the camera 62. In addition, when the second captured image is generated, it is assumed that only the light having the wavelength λ <b> 2 is incident on the camera 62.

  Based on the third captured image from the camera 62, the information processing apparatus 63 maintains the irradiated light components of the wavelengths λ1 and λ2 received by the camera 62 and suppresses the external light components of the wavelengths λ1 and λ2. As described above, the timing of exposure by the camera 62 and the exposure time of the camera 62 are determined.

  Then, the information processing device 63 controls the camera 62 and the like with the determined exposure time and the like to generate the first and second captured images.

  As a result, when the camera 62 generates the first and second captured images, the amount of the received external light components of the wavelengths λ1 and λ2 is reduced to an extent that does not affect the detection of the skin region. Therefore, the information processing apparatus 63 can detect the skin region using the reflectances of the wavelengths λ1 and λ2 based on the first and second captured images from the camera 62.

[Processing performed by information processing device 63]
Next, with reference to FIG. 4 and FIG. 5, the detection of the skin area using the reflectances of the wavelengths λ1 and λ2 performed by the information processing device 63 will be described.

[Spectral reflection characteristics for skin]
FIG. 4 shows spectral reflection characteristics with respect to human skin.

  This spectral reflection characteristic has generality regardless of the color of human skin (difference in race) or the state (sunburn, etc.).

  In FIG. 4, the horizontal axis indicates the wavelength of the irradiation light irradiated on the human skin, and the vertical axis indicates the reflectance of the irradiation light irradiated on the human skin.

  It is known that the reflectance of irradiated light radiated on human skin decreases rapidly from around 900 [nm], peaking around 800 [nm], and rises again around 1000 [nm] as a minimum. ing.

  Specifically, for example, as shown in FIG. 4, the reflectance of reflected light obtained by irradiating human skin with light of 870 [nm] is 63 [%], and 950 [nm] The reflectance of the reflected light obtained by irradiating the light of 50] is 50 [%].

  This is peculiar to human skin. For objects other than human skin (for example, hair, clothes, etc.), the change in reflectance is moderate around 800 to 1000 [nm]. Many.

  In the present embodiment, in the above-described spectral reflection characteristics, for example, a combination in which the wavelength λ1 is 870 [nm] and the wavelength λ2 is 950 [nm] is employed as the combination of the wavelengths λ1 and λ2. This combination is a combination in which the difference in reflectance with respect to human skin is relatively large, and the difference in reflectance with respect to portions other than human skin is relatively small.

  Further, as described above, since the external light component of the wavelength λ1 received by the camera 62 is suppressed to the extent that it does not affect the detection of the skin region, the first captured image is the irradiation light of the wavelength λ1. It can be considered that it is composed of a region obtained by receiving only components.

  Similarly, since the external light component of the wavelength λ2 received by the camera 62 is suppressed to the extent that it does not affect the detection of the skin region, the second captured image receives only the irradiation light component of the wavelength λ2. Thus, it can be considered that the area is constituted by the obtained area.

  Therefore, the absolute difference between the luminance value of the pixel constituting the skin area on the first captured image and the luminance value constituting the skin area on the corresponding second captured image is the reflectance of human skin. Corresponding to the difference, the value is relatively large.

  Also, the absolute value of the difference between the luminance value of the pixel constituting the non-skin area (area other than the skin area) on the first captured image and the luminance value constituting the non-skin area on the corresponding second captured image. Corresponds to a relatively small value corresponding to the difference in reflectance with respect to portions other than human skin.

[Outline of processing performed by information processing device 63]
FIG. 5 shows an outline of processing performed by the information processing apparatus 63.

  The information processing device 63 controls the camera 62 and the like so as to suppress the external light component of the wavelength λ1 while maintaining the irradiation light component of the wavelength λ1, and causes the camera 62 to capture the first captured image. It is made to supply to the processing apparatus 63.

  Further, the information processing device 63 controls the camera 62 and the like so as to capture the second captured image so as to suppress the external light component of the wavelength λ2 while maintaining the irradiation light component of the wavelength λ2. The information processing device 63 is supplied.

  The information processing apparatus 63 receives from the camera 62 a first captured image 81 composed of a skin region 81a and a non-skin region 81b (a region other than the skin region 81a), and a skin region 82a and a non-skin region 82b (skin A second captured image 82 composed of a region other than the region 82a) is supplied.

  The information processing apparatus 63 smoothes the first captured image 81 and the second captured image 82 supplied from the camera 62 using LPF (low pass filer). Then, the information processing device 63 calculates a difference absolute value between the luminance values of the corresponding pixels of the first captured image 81 after smoothing and the second captured image 82 after smoothing, and the difference absolute A difference image 83 having a value as a pixel value is generated.

  The information processing device 63 sets the pixel value that is greater than or equal to a predetermined threshold among the pixel values that constitute the difference image 83 to the generated difference image 83, and sets the pixel value that is less than the predetermined threshold to 0. To do.

  In this case, the skin region 83a in the difference image 83 is composed of pixels whose pixel value is the absolute value of the difference between the luminance values of the corresponding pixels of the skin region 81a and the skin region 82a. The pixel value of the constituent pixels is a relatively large value.

  Further, the non-skin region 83b in the difference image 83 is composed of pixels having the pixel value as the absolute value of the difference between the luminance values of corresponding pixels in the non-skin region 81b and the non-skin region 82b. The pixel values of the pixels constituting 83b are relatively small values.

  Therefore, the difference image 83 is obtained by binarization performed by the information processing device 63, and the pixel values of the pixels constituting the skin region 84a and the non-skin region 83b in which the pixel value of the pixels constituting the skin region 83a is set to 1. Is converted to a binarized image 84 composed of non-skin regions 84b.

  Then, the information processing device 63 detects a skin region 84a constituted by pixels having a pixel value of 1 among the pixels constituting the binarized image 84 obtained by the binarization as a skin region.

[Configuration Example of Information Processing Device 63]
Next, FIG. 6 shows a configuration example of the information processing apparatus 63.

  The information processing apparatus 63 includes a control unit 101, a difference image generation unit 102, and a binarization unit 103.

  In order to cause the camera 62 to generate the first and second captured images, the control unit 101 generates and generates a VD signal (vertical synchronization signal) that generates a rising edge in accordance with the period for capturing one frame. Based on the VD signal, the light emitting device 61 and the camera 62 are controlled. In this case, the camera 62 supplies the first and second captured images obtained by the imaging to the difference image generation unit 102.

  The details of the control by the control unit 101 performed to cause the camera 62 to generate the first and second captured images will be described later with reference to FIG.

  In addition, the control unit 101 causes the camera 62 to image the subject in a state where the LED 21a and the LED 21b of the light emitting device 61 are turned off in order to cause the camera 62 to capture the third captured image. In this case, the camera 62 supplies the third captured image obtained by the imaging to the control unit 101.

  The control unit 101 determines the exposure time (shutter speed) by the camera 62 based on the luminance value of the pixels constituting the third captured image from the camera 62. Details of the method for determining the exposure time will be described later with reference to FIG.

  The difference image generation unit 102 is supplied with the first and second captured images obtained by capturing with the camera 62.

  The first captured image is obtained by receiving the external light component having the wavelength λ1 and the irradiation light component having the wavelength λ1, and the second captured image is the external light component having the wavelength λ2 and the wavelength. It is obtained by receiving the irradiation light component of λ2.

  The difference image generation unit 102 performs smoothing using LPF on the first and second captured images from the camera 62. And the difference image generation part 102 calculates the difference absolute value of the 1st captured image after smoothing, and the 2nd captured image, The difference image comprised by the pixel which uses the calculated difference absolute value as a pixel value Is supplied to the binarization unit 103.

  The binarization unit 103 binarizes the difference image from the difference image generation unit 102, and based on the binarized image obtained as a result, the skin area on the first captured image (or the second captured image) Is detected and the detection result is output.

[Example of control by the control unit 101]
Next, FIG. 7 shows an example in which the control unit 101 controls the light emitting device 61 and the camera 62 to cause the camera 62 to generate first and second captured images.

  For example, in the case of 60 fps, as illustrated in FIG. 7A, the control unit 101 generates a VD signal that generates a rising edge every 16.7 [ms] (= 1/60 [s]) as a VD signal. Then, the control unit 101 performs exposure of the camera 62 with the exposure time determined based on the third captured image, and controls the LED 21a and the LED 21b to emit light.

  That is, for example, as illustrated in FIG. 7B, the control unit 101 sets 8.35 [ms] (= 1/120 [s]) from the timing at which an odd-numbered rising edge occurs among a plurality of rising edges generated in the generated VD signal. ) Start the light emission of the LED 21a at a timing delayed by a), and end the light emission after 8.35 [ms] from the start of the light emission.

  For example, as illustrated in FIG. 7C, the control unit 101 sets the LED 21b at a timing delayed by 8.35 [ms] from the timing at which the even-numbered rising edge occurs among the plurality of rising edges generated in the generated VD signal. The light emission is started, and the light emission is terminated 8.35 [ms] after the start of the light emission.

  Further, for example, as shown in FIG. 7D, the control unit 101 starts exposure of the camera 62 at a timing delayed by 8.35 [ms] from the timing at which each of a plurality of rising edges generated in the generated VD signal occurs. The exposure is terminated after 8.35 [ms] from the start of exposure.

  In addition, the control unit 101 determines that the total amount of light of the wavelength λ1 emitted from the LED 21a is a constant amount corresponding to the wavelength λ1 at any exposure time that changes according to the third captured image from the camera 62. At the same time, the LED 21a and the LED 21b are controlled so that the total amount of light of the wavelength λ2 emitted from the LED 21b becomes a constant amount corresponding to the wavelength λ2.

Note that the constant amount according to the wavelength λ1 and the constant amount according to the wavelength λ2 are, for example, absolute differences in the skin region even if noise or the like occurs in the skin region of the first and second captured images. The amount of light with which the value | α ₁ ′ −β ₁ ′ | is a relatively large value, that is, the amount of charge necessary to generate the first and second captured images capable of detecting the skin area with high accuracy. The amount of light obtained is adopted.

  Further, as a control method for controlling the light quantity of the LED 21a and the LED 21b in the control unit 101, for example, the on state and the off state of the current are switched by switching, and the ratio (duty ratio) between the on state and the off state is variable. By doing so, it is possible to use a PWM (Pulse Width Modulation) control method for controlling the allowable maximum current.

Therefore, in the camera 62, as shown in FIG. 7E, the charge amount of the charge accumulated by the irradiation light components of the wavelengths λ1 and λ2 is the charge amounts α ₁ and β ₁ regardless of the exposure time of 8.35 [ms]. Maintained.

Further, since exposure is performed with an exposure time of 8.35 [ms] in the camera 62, as shown in FIG. 7F, the charge amount of charges accumulated by the external light components of the wavelengths λ1 and λ2 is the charge amount α ₂ / It is suppressed to 2 and beta _2/2.

For this reason, as shown in FIG. 7G, the total charge amount of charges accumulated by the irradiation light component of wavelength λ1 and the external light component of wavelength λ1 is less than the maximum charge amount max that can be accumulated. α ₁ + to become (α _2/2). The camera 62 generates a first captured image constituted by the charge amount _{α 1 + (α 2/2} ) corresponding luminance value, and supplies the difference image generation unit 102.

The irradiation light component of the wavelength .lambda.2, and the total charge quantity of the charge stored by the outside light component of the wavelength .lambda.2 is a charge amount of less than the maximum charge amount _{max β 1 + (β 2/} 2). The camera 62 generates a second captured image constituted by the charge amount _{β 1 + (β 2/2} ) corresponding luminance value, and supplies the difference image generation unit 102.

In this embodiment, in the camera 62, the amount of charge accumulated by the outside light component of the wavelength λ1 and .lambda.2, since so as to suppress the charge quantity alpha _2/2 and beta _2/2, in Figure 8 It is possible to prevent overexposure as shown.

As another method for preventing overexposure, for example, as shown in FIG. 9, the amount of charge α ₂ and β obtained by adjusting the aperture of the camera 62 and the external light components of the wavelengths λ1 and λ2 is adjusted. It is conceivable to suppress ₂ to 1/2, for example. Further, for example, as shown in FIG. 10, the amount of charge α ₂ obtained by the external light components of the wavelengths λ1 and λ2 by adjusting the shutter speed of the camera 62 so that the exposure time becomes, for example, ½. And β ₂ can be suppressed to 1/2.

According to the method of adjusting the aperture of the camera 62 as shown in FIG. 9 and the method of adjusting the shutter speed of the camera 62 as shown in FIG. 10, the cause of overexposure (the accuracy of skin detection for detecting the skin region) It is possible to sufficiently suppress the charge amounts α ₂ and β ₂ that cause the decrease).

However, in these cases, the charge amounts α ₁ and β ₁ necessary for detecting the skin region are also significantly suppressed.

Therefore, in the present embodiment, as described with reference to FIG. 7, while maintaining the charge amounts (α ₁ and β _{1 in} FIG. 7) accumulated by the irradiation light components of the wavelengths λ1 and λ2, amount of charge accumulated by the outside light component of the wavelength λ1 and the wavelength .lambda.2 (referred to FIG. 7 alpha _2/2 and beta _2/2) to be sufficiently suppressed, the skin detection accuracy for detecting the skin region of the captured image I try to improve.

[Example of how to determine exposure time]
Next, an example of a determination method for determining the exposure time based on the third captured image from the camera 62 performed by the control unit 101 will be described with reference to FIG.

  FIG. 11A shows a third captured image 121 obtained by receiving only the external light component of wavelength λ1 with an exposure time of 16.7 [ms]. A third captured image 121 shown in FIG. 11A is composed of a skin region 121a and a non-skin region 121b. Note that the maximum value of the luminance values of the pixels constituting the skin region 121a shown in FIG.

  FIG. 11B shows a third captured image 121 obtained by receiving only the external light component of wavelength λ1 with an exposure time of 8.35 [ms]. The third captured image 121 shown in FIG. 11B includes a skin region 121a and a non-skin region 121b. Note that the maximum value of the luminance values of the pixels constituting the skin region 121a shown in FIG.

In the present embodiment, the gradation of the luminance value is N bits, and the maximum luminance value is 2 ^N −1.

  In this case, in order to prevent overexposure, the amount of charges accumulated in the skin region needs to satisfy the following conditional expressions (1) and (2).

α ₂ <max−α ₁ (1)

β ₂ <max−β ₁ (2)

The charge amount α ₁ represents the amount of charge accumulated by the irradiation light component having the wavelength λ1, and the charge amount α ₂ represents the charge amount accumulated by the external light component having the wavelength λ1. The maximum charge amount max represents the maximum amount that can store charges.

Further, the charge amount β ₁ represents the amount of charge accumulated by the irradiation light component having the wavelength λ2, and the charge amount β ₂ represents the amount of charge accumulated by the external light component having the wavelength λ2.

  When conditional expressions (1) and (2) are converted into conditional expressions for luminance values, the following conditional expressions (1 ′) and (2 ′) are obtained.

α ₂ ′ <(2 ^N −1) −α ₁ ′ (1 ′)

β ₂ ′ <(2 ^N −1) −β ₁ ′ (2 ′)

The luminance value α ₁ ′ represents the luminance value corresponding to the charge amount α ₁ , and the luminance value α ₂ ′ represents the luminance value corresponding to the charge amount α ₂ . The maximum luminance value (2 ^N −1) represents the luminance value corresponding to the maximum charge amount max.

Further, the luminance value β ₁ ′ represents a luminance value corresponding to the charge amount β ₁ , and the luminance value β ₂ ′ represents a luminance value corresponding to the charge amount β ₂ .

  As described above, the output of the LED 21a and the LED 21b is obtained by the imaging of the camera 62 when the subject having the same reflectance with respect to the wavelengths λ1 and λ2 is irradiated with light of either wavelength λ1 or λ2. The obtained captured image is adjusted according to the determined exposure time so that the luminance values of the corresponding pixels are the same.

That is, for example, the output of the LED 21a is obtained when the light of the wavelength λ1 from the LED 21a is reflected on the mirror surface of the mirror whose reflectivity of the wavelength λ1 and the wavelength λ2 is 100% in the determined exposure time. Is adjusted so that the charge amount α ₁ obtained in step ₁ becomes the charge amount corresponding to the predetermined luminance value x.

Further, for example, the output of LED21b, in determined exposure time, a mirror, a charge amount of the charge amount beta ₁ obtained when light is reflected corresponds to a predetermined luminance value x of the wavelength λ2 from LED21b To be adjusted.

Accordingly, the maximum values of the luminance values α ₁ ′ and β ₁ ′ are respectively predetermined luminance values x.

Therefore, in order to prevent overexposure due to the luminance value α ₂ ′, it is necessary to satisfy the following formula (1 ″). Further, in order to prevent overexposure due to the luminance value β ₂ ′, it is necessary to satisfy the following formula (2 ″).

α ₂ ′ <(2 ^N −1) −x (1 ″)

β ₂ ′ <(2 ^N −1) −x (2 ″)

In the present embodiment, the luminance value α ₂ ′ obtained by receiving the external light component having the wavelength λ1 at any exposure time is obtained from the luminance value β ₂ ′ obtained by receiving the external light component having the wavelength λ2. Is also getting bigger.

  Therefore, since the exposure time that satisfies the formula (1 ″) is the exposure time that also satisfies the formula (2 ″), the control unit 101 uses the formula (1) based on the third captured image from the camera 62. '') (Or the exposure time satisfying the equation (1)) is determined.

  That is, for example, the control unit 101 causes the camera 62 to receive an external light component having the wavelength λ1 with an exposure time of 16.7 [ms] with the LED 21a and the LED 21b turned off, and the first unit as illustrated in FIG. 11A. 3 captured images are acquired.

Then, the control unit 101 detects the maximum luminance value α ₂ ′ among the luminance values of the pixels constituting the skin area on the acquired third captured image, and determines the exposure time based on the detection result. To do.

Specifically, for example, when N = 8 and x = 100, the maximum luminance value α ₂ ′ needs to be less than 155 (= 255-100). In this case, as shown in FIG. 10A, the control unit 101 has the maximum luminance among the luminance values of the pixels constituting the skin region 121a on the third captured image 121 captured with an exposure time of 16.7 [ms]. When the value α ₂ ′ is the luminance value 200, as shown in FIG. 10B, the exposure time is determined to be 8.35 [ms] when the luminance value 200 becomes the luminance value 100 less than 155.

In the present embodiment, the luminance value α ₂ ′ obtained by receiving the external light component having the wavelength λ1 at any exposure time is the luminance value β ₂ obtained by receiving the external light component having the wavelength λ2. It was supposed to be bigger than '. However, in any exposure time, when the luminance value α ₂ ′ is smaller than the luminance value β ₂ ′, the exposure time is determined as described below.

  That is, in this case, since the exposure time that satisfies the formula (2 ″) is the exposure time that also satisfies the formula (1 ″), the control unit 101 determines that the formula (2 ″) (or the formula (2)) is satisfied. An exposure time that satisfies the above is determined.

  Specifically, the control unit 101 causes the camera 62 to receive an external light component having the wavelength λ2 with an exposure time of 16.7 [ms] with the LED 21a and the LED 21b turned off, and a fourth imaging obtained as a result. Get an image.

Then, the control unit 101 detects the maximum luminance value β ₂ ′ among the luminance values of the pixels constituting the skin area on the acquired fourth captured image, and sets the exposure time based on the third captured image. The exposure time is determined in the same manner as when it is determined.

Note that, in any exposure time, when the brightness value α ₂ ′ is smaller than the brightness value β ₂ ′, the present embodiment is the same as the present embodiment except that the exposure time is determined using the fourth captured image. Similarly, detection of a skin region and the like are performed.

[Explanation of skin detection processing]
Next, details of the skin detection process performed by the information processing system 41 will be described with reference to the flowchart of FIG.

  This skin detection process is started, for example, when the information processing system 41 is turned on by the user.

  In step S1, the control unit 101 determines the exposure timing by the camera 62, the exposure time by the camera 62, the light emission timing by the LED 21a of the light emitting device 61, and the LED 21a based on setting information previously stored in a storage unit (not shown). , The light emission timing by the LED 21b of the light emitting device 61, and the light emission time by the LED 21b are determined. Here, the setting information refers to information for setting the timing of exposure by the camera 62 and the like.

  Further, the setting information is created in advance by performing the same processing as the processing in steps S6 to S8 described later before the skin detection processing is performed.

  That is, for example, in step S1, the control unit 101 sets the timing of light emission by the LED 21a of the light emitting device 61 to the same timing as the exposure timing determined based on the odd-numbered rising edge generated in the VD signal.

  Also, for example, the control unit 101 sets the timing of light emission by the LED 21b of the light emitting device 61 to the same timing as the exposure timing determined based on the even-numbered rising edge generated in the VD signal.

  Then, the control unit 101 sets the light emission time by the LED 21a and the light emission time by the LED 21b of the light emitting device 61 to the same time as the exposure time by the camera 62, respectively.

  In step S2, the control unit 101 generates a VD signal and emits light for the exposure time from the same timing as the exposure timing determined in the process of step S1, based on the odd-numbered rising edge generated in the generated VD signal. The LED 21a of the device 61 is caused to emit light. As a result, the subject is irradiated with light of wavelength λ1 from the LED 21a in addition to the external light source.

  In step S3, the control unit 101 causes the camera 62 to perform exposure for the exposure time from the exposure timing determined in step S1 based on the odd-numbered rising edge generated in the generated VD signal. Accordingly, the camera 62 generates a first captured image obtained by receiving the irradiation light component of the wavelength λ1 and the external light component of the wavelength λ1, and supplies the first captured image to the difference image generation unit 102.

  After the light emission of the LED 21a by the process of step S2 and the exposure of the camera 62 by the process of step S3 are completed, in step S4, the control unit 101 performs step S1 based on the even-numbered rising edge generated in the generated VD signal. The LED 21b of the light emitting device 61 is caused to emit light for the exposure time from the exposure timing determined in the above process. As a result, the subject is irradiated with light of wavelength λ2 from the LED 21b in addition to the external light source.

  In step S5, the control unit 101 causes the camera 62 to perform exposure for the exposure time from the exposure timing determined in step S1, based on the even-numbered rising edge generated in the generated VD signal. Accordingly, the camera 62 generates a second captured image obtained by receiving the irradiation light component having the wavelength λ <b> 2 and the external light component having the wavelength λ <b> 2, and supplies the second captured image to the difference image generation unit 102.

  After the light emission of the LED 21b by the process of step S4 and the exposure of the camera 62 by the process of step S5 are finished, in step S6, the control unit 101 decides by the process of step S1 with the LED 21a and the LED 21b turned off. The camera 62 receives the reflected light of the light having the wavelength λ1 emitted from the external light source to the subject for the exposure time from the exposure timing. As a result, the camera 62 generates a third captured image obtained by receiving only the external light component having the wavelength λ <b> 1 and supplies the third captured image to the control unit 101.

  In step S <b> 7, the control unit 101 determines whether or not the maximum luminance value among the luminance values of the pixels constituting the skin area on the third captured image from the camera 62 satisfies the conditional expression (1 ″). That is, it is determined whether or not the maximum luminance value is less than a predetermined threshold value (for example, threshold value 155).

  In step S7, when the control unit 101 determines that the maximum luminance value of the luminance values of the pixels constituting the skin area of the third captured image from the camera 62 is not less than the predetermined threshold value, Advances to step S8.

  In step S8, the control unit 101 determines (changes) the exposure timing, the exposure time, and the like based on the maximum luminance value among the luminance values of the pixels constituting the skin area of the third captured image from the camera 62. ) Further, the control unit 101 adjusts the output of the LED 21a and the LED 21b according to the determined exposure time. And the control part 101 returns a process to step S2, and performs the same process after that.

  In step S7, when the control unit 101 determines that the maximum luminance value among the luminance values of the pixels constituting the third captured image from the camera 62 is less than the predetermined threshold value, the process proceeds to step S7. Proceed to S9.

  In step S9 and step S10, the control unit 101 controls the difference image generation unit 102 and the binarization unit 103 to perform detection of the skin region and to instruct to perform a gesture operation according to the detection result. Output to the subsequent stage.

  That is, in step S <b> 9, the difference image generation unit 102 performs smoothing using LPF on the first captured image and the second captured image from the camera 62. And the difference image generation part 102 calculates the difference absolute value of the 1st captured image after smoothing, and the 2nd captured image, The difference image comprised by the pixel which uses the calculated difference absolute value as a pixel value Is supplied to the binarization unit 103.

  In step S10, the binarization unit 103 binarizes the difference image from the difference image generation unit 102, and based on the binarized image obtained as a result, the first captured image (or the second captured image). An instruction to detect the upper skin region and perform a gesture operation corresponding to the detection result is output to the subsequent stage.

  And after completion | finish of step S10, a process returns to step S2, and the same process is performed after that.

  Note that this skin detection process is ended, for example, when the information processing system 41 is turned off by the user.

  As described above, in the skin detection process, the exposure timing, the exposure time, and the like are changed based on the third captured image obtained by receiving only the external light component having the wavelength λ1.

  As a result, in the skin detection process, the amount of charge accumulated by the irradiated light components of wavelengths λ1 and λ2 is maintained, and the amount of charge accumulated by the external light components of wavelengths λ1 and λ2 is sufficiently suppressed. Therefore, for example, compared with the conventional skin recognition system 1, it becomes possible to improve the skin detection accuracy which detects the skin area | region on a captured image.

  In the skin detection process, the total light amount of the light with the wavelength λ1 emitted from the LED 21a becomes a constant amount according to the wavelength λ1 at any exposure time that changes according to the third captured image. The LED 21a and the LED 21b are controlled so that the total amount of light with the wavelength λ2 emitted from the LED 21b becomes a constant amount corresponding to the wavelength λ2.

  Therefore, in the present embodiment, the power consumption consumed by each of the LED 21a and the LED 21b and the total amount of light emitted within the exposure time are both the same as those of the conventional skin recognition system 1.

  Therefore, in the present embodiment, compared to the conventional skin recognition system 1, the power consumption is not increased, and the charges due to the external light components of the wavelengths λ1 and λ2 are reduced without shortening the distance from the LED 21a and the LED 21b to the subject. The amount can be suppressed.

<2. Modification>
In the present embodiment, in the skin detection process, the control unit 101 changes the exposure timing, the exposure time, and the like according to the third captured image from the camera 62. However, the present invention is not limited to this.

  That is, for example, in the skin detection process, the process by steps S2 to S5, step S9, and step S10 may be performed without changing the exposure timing and the exposure time that are determined in advance in step S1. In this case, it is not necessary to change the exposure timing and the exposure time according to the third captured image from the camera 62, so that the processing speed for detecting the skin region can be increased.

  In this embodiment, the timing of light emission by the LED 21a and the LED 21b is made to coincide with the timing of exposure by the camera 62, but the timing of light emission is not limited to this.

  That is, the light emission timing is such that the total amount of light of wavelength λ1 emitted from the LED 21a within the exposure time is a constant amount corresponding to the wavelength λ1, and the light of wavelength λ2 emitted from the LED 21b within the exposure time. The light may be emitted at any timing as long as the total light amount is a constant amount corresponding to the wavelength λ2.

  Specifically, for example, the timing of light emission by the LED 21a and the LED 21b is shifted from the timing of exposure by the camera 62 so that the LED 21a and the LED 21b emit light within the exposure time with a light emission time shorter than the exposure time. Alternatively, light may be emitted with a light emission time longer than the exposure time, including part or all of the exposure time.

  In this case, the control unit 101 determines that the total amount of light of the wavelength λ1 emitted from the LED 21a within the exposure time is a constant amount corresponding to the wavelength λ1 and the LED 21b within the exposure time at any light emission time. The LED 21a and the LED 21b are respectively controlled so that the total light amount of the light with the wavelength λ2 emitted from the light source becomes a constant amount corresponding to the wavelength λ2.

  In the present embodiment, the wavelength λ1 emitted from the LED 21a is 870 [nm] and the wavelength λ2 emitted from the LED 21b is 950 [nm]. However, the combination of wavelengths is not limited to this.

  That is, as a combination of wavelengths, the absolute difference between the reflectance at the wavelength λ1 and the reflectance at the wavelength λ2 is sufficiently larger than the absolute difference between the reflectances obtained for things other than the user's skin. Any combination is possible as long as it is a combination.

  Specifically, as is apparent from FIG. 4, for example, in addition to the combination of 870 [nm] and 950 [nm], the combination of 800 [nm] and 950 [nm], 870 [nm] and 1000 [nm] The LED 21a emits light having a wavelength λ1 of less than 930 [nm], and the LED 21b has a wavelength λ2 of 930 [nm] or more, such as a combination with nm] or a combination of 800 [nm] and 1000 [nm] It can be configured to emit light.

  In the case where visible light is used as the light of wavelength λ1, it is necessary to remove the visible light cut filter 62a from the camera 62, for example, so that the visible light having the wavelength λ1 is not blocked by the visible light cut filter 62a. There is. The same applies to the case where visible light is used as the light of wavelength λ2.

  In the present embodiment, the information processing system 41 that detects a skin region from the first or second captured image has been described. However, the information processing system 41 is built in an electronic device such as a television receiver. Is possible.

  In this case, for example, in a television receiver in which the information processing system 41 is built, the channel is changed in accordance with the detection result of the skin area detected by the information processing system 41.

  By the way, the series of processes described above can be executed by dedicated hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software can execute various functions by installing a so-called embedded computer or various programs. For example, it is installed from a recording medium in a general-purpose personal computer or the like.

[Computer configuration example]
Next, FIG. 13 shows a configuration example of a personal computer that executes the above-described series of processing by a program.

  A CPU (central processing unit) 201 executes various processes according to a program stored in a ROM (read only memory) 202 or a storage unit 208. A RAM (random access memory) 203 appropriately stores programs executed by the CPU 201, data, and the like. These CPU 201, ROM 202, and RAM 203 are connected to each other by a bus 204.

  An input / output interface 205 is also connected to the CPU 201 via the bus 204. Connected to the input / output interface 205 are an input unit 206 composed of a keyboard, a mouse, a microphone, and the like, and an output unit 207 composed of a display, a speaker, and the like. The CPU 201 executes various processes in response to commands input from the input unit 206. Then, the CPU 201 outputs the processing result to the output unit 207.

  A storage unit 208 connected to the input / output interface 205 includes, for example, a hard disk, and stores programs executed by the CPU 201 and various data. The communication unit 209 communicates with an external device via a network such as the Internet or a local area network.

  Further, a program may be acquired via the communication unit 209 and stored in the storage unit 208.

  The drive 210 connected to the input / output interface 205 drives a removable medium 211 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and drives programs and data recorded there. Etc. The acquired program and data are transferred to and stored in the storage unit 208 as necessary.

  As shown in FIG. 13, a recording medium for recording (storing) a program that is installed in a computer and can be executed by the computer is a magnetic disk (including a flexible disk), an optical disk (CD-ROM (compact disc- read only memory), DVD (digital versatile disc)), magneto-optical disc (including MD (mini-disc)), or removable media 211 that is a package media made of semiconductor memory, etc. It is composed of a ROM 202 that is permanently stored, a hard disk that constitutes the storage unit 208, and the like. Recording of a program on a recording medium is performed using a wired or wireless communication medium such as a local area network, the Internet, or digital satellite broadcasting via a communication unit 209 that is an interface such as a router or a modem as necessary. Is called.

  In the present specification, the steps describing the series of processes described above are not limited to the processes performed in time series according to the described order, but are not necessarily performed in time series, either in parallel or individually. The process to be executed is also included.

  Further, in this specification, the system represents the entire apparatus constituted by a plurality of apparatuses.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  21a, 21b LED, 41 information processing system, 61 light emitting device, 61a diffuser plate, 62 camera, 62a visible light cut filter, 63 information processing device, 101 control unit, 102 difference image generation unit, 103 binarization unit

Claims (13)

In a detection device for detecting the subject from a captured image obtained by imaging the subject,
Irradiating means for irradiating the subject with light of a predetermined wavelength;
Imaging means for generating a captured image obtained by imaging the subject, using a total charge amount of each pixel accumulated by receiving reflected light from the subject as a pixel value;
Detecting means for detecting the subject from the captured image;
Irradiation control for controlling the irradiating means to irradiate the first charge amount accumulated by receiving reflected light of the light irradiated by the irradiating means out of the total charge amount with a predetermined charge amount. Means,
The second charge amount that is stored by receiving the reflected light of the light irradiated by outside light among the total charge amount is controlled from the maximum charge amount that can be accumulated. And an imaging control means for receiving light with an exposure time that is less than a difference value obtained by subtracting the amount of charge of 1 . The detection apparatus according to claim 1, wherein the irradiation control unit irradiates the first charge amount with an amount of light that is a charge amount necessary to generate the captured image for detecting the subject. Further comprising a changing means for changing the exposure time of the imaging means based on the second charge amount accumulated in the exposure time;
The detection apparatus according to claim 1, wherein the imaging control unit receives light with the changed exposure time. The detection device according to claim 1, wherein the irradiation control unit irradiates with an irradiation time that is the same as the exposure time. The detection apparatus according to claim 1, wherein the irradiation control unit irradiates within an exposure time with an irradiation time shorter than the exposure time. The detection apparatus according to claim 1, wherein the irradiation control unit performs irradiation with an irradiation time longer than the exposure time including the exposure time. The irradiation means includes
First output means for irradiating a subject with light of a first wavelength;
A second output means for irradiating the subject with light having a second wavelength different from the first wavelength;
The imaging means includes
A first captured image is generated using a total charge amount of each pixel accumulated by receiving reflected light of the first wavelength as a pixel value,
Generating a second captured image using the total charge amount of each pixel accumulated by receiving reflected light of the second wavelength as a pixel value;
The detection device according to claim 1, wherein the detection unit detects the subject on one captured image of the first or second captured image based on the first and second captured images. The first and second output means are obtained by irradiating the human skin with the reflectance of the reflected light obtained by irradiating the light of the first wavelength and the light of the second wavelength. Irradiate light with a wavelength when the absolute value of the difference from the reflectance of the reflected light is greater than or equal to a predetermined difference threshold
The detection device according to claim 7 . The first and second output means irradiate infrared rays having different wavelengths, respectively.
The detection device according to claim 8 . One of the first or second output means emits light having a wavelength of 930 [nm] or more, and the other emits light of less than 930 [nm].
The detection device according to claim 9 . In the detection method of the detection device for detecting the subject from a captured image in which the total charge amount of each pixel accumulated by receiving reflected light from the subject is a pixel value,
The detection device includes:
Irradiation means;
Imaging means;
Detection means;
Irradiation control means;
Imaging control means, and
The irradiation control unit controls the irradiation unit that irradiates a subject with light having a predetermined wavelength, and receives and accumulates the reflected light of the light irradiated by the irradiation unit out of the total charge amount. The amount of charge is irradiated with a light amount that becomes a predetermined amount of charge,
The imaging control unit controls the imaging unit to generate a captured image obtained by imaging the subject, using the total charge amount of each pixel accumulated by receiving reflected light from the subject as a pixel value, and the total charge The difference obtained by subtracting the first charge amount from the maximum charge amount that can be accumulated by the second charge amount accumulated by receiving the reflected light of the light irradiated by external light among the amount Receive light with an exposure time less than the value ,
A detection method including a step in which the detection means detects the subject from the captured image. A computer of a detection device that detects the subject from a captured image obtained by imaging the subject,
Irradiating means for irradiating the subject with light of a predetermined wavelength;
Imaging means for generating a captured image obtained by imaging the subject, using a total charge amount of each pixel accumulated by receiving reflected light from the subject as a pixel value;
Detecting means for detecting the subject from the captured image;
Irradiation control for controlling the irradiating means to irradiate the first charge amount accumulated by receiving reflected light of the light irradiated by the irradiating means out of the total charge amount with a predetermined charge amount. Means,
The second charge amount that is stored by receiving the reflected light of the light irradiated by outside light among the total charge amount is controlled from the maximum charge amount that can be accumulated. A program for functioning as an imaging control means for receiving light with an exposure time that is less than a difference value obtained by subtracting the charge amount of 1 . In an electronic device incorporating a detection device that detects the subject from a captured image obtained by imaging the subject,
The detection device includes:
Irradiating means for irradiating the subject with light of a predetermined wavelength;
Imaging means for generating a captured image obtained by imaging the subject, using a total charge amount of each pixel accumulated by receiving reflected light from the subject as a pixel value;
Detecting means for detecting the subject from the captured image;
Irradiation control for controlling the irradiating means to irradiate the first charge amount accumulated by receiving reflected light of the light irradiated by the irradiating means out of the total charge amount with a predetermined charge amount. Means,
The second charge amount that is stored by receiving the reflected light of the light irradiated by outside light among the total charge amount is controlled from the maximum charge amount that can be accumulated. And an imaging control means for receiving light with an exposure time that is less than a difference value obtained by subtracting the amount of charge of 1 .

Images