Measurement device, measurement method, and program

Abstract

To provide a measuring apparatus capable of suppressing deterioration of calculation accuracy of biological information due to an inappropriate pixel.SOLUTION: The measuring apparatus comprises: an imaging unit which images a living body to acquire an image; a determination index calculation unit which concerning a region of interest included in the image, calculates a determination index concerning the number of object pixels having pixel values which are at least a predetermined lower limit but not larger than a predetermined upper limit; and a biological information calculation unit which calculates biological information from the pixel values of pixels included in a region of interest where the determination index is a threshold value or more.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a measurement device, a measurement method, and a program. [Background technology]

[0002] Patent document 1 discloses a technology that calculates the difference between luminance information of a video signal of a skin area showing a subject's face and luminance information of a video signal of a skin area showing a part of the subject's face other than the face at the same time as the video signal of the subject's face, and measures fluctuations in the subject's blood pressure according to the increase or decrease in the calculated difference. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-190022 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is a method of imaging the skin, acquiring information on the surface and blood vessels inside the skin, and calculating biometric information. For example, in the technology disclosed in Patent Document 1, pixels with luminance information corresponding to the skin color are extracted from a manually set region of interest, and the region where the extracted pixels are grouped is set as the skin region. However, in the technology disclosed in Patent Document 1, if the skin region contains inappropriate pixels containing information unrelated to blood vessels, such as black crush due to the surroundings being too dark, spots, wrinkles, etc., the biometric information may not be calculated accurately. This is because inappropriate pixels containing information unnecessary for calculating the biometric information may not accurately reflect the biometric information, and if a large number of such inappropriate pixels are included in the image, it becomes difficult to accurately calculate the biometric information. Examples of inappropriate pixels include the above-mentioned pixels that are too dark and black crushed, pixels that are dark due to spots, wrinkles, moles, and shadows on the face, and pixels that are too bright due to strong lighting or sunlight. Therefore, one aspect of the present disclosure aims to provide a measuring device, a measuring method, and a program that can accurately calculate biometric information by using appropriate pixels. [Means for solving the problem]

[0005] A measurement device according to one aspect of the present disclosure includes an imaging unit that captures an image of a living body, a judgment index calculation unit that calculates a judgment index related to the number of target pixels having pixel values ​​that are equal to or greater than a predetermined lower limit and equal to or less than a predetermined upper limit for a region of interest included in the image, and a biometric information calculation unit that calculates biometric information from the pixel values ​​of pixels included in the region of interest whose judgment index is equal to or greater than a threshold value.

[0006] A measurement method according to one aspect of the present disclosure includes the steps of: capturing an image of a living body; calculating a judgment index relating to the number of target pixels having pixel values ​​that are greater than or equal to a predetermined lower limit and less than or equal to a predetermined upper limit for a region of interest included in the image; and calculating biometric information from the pixel values ​​of pixels included in the region of interest whose judgment index is greater than or equal to a threshold value.

[0007] A program according to one aspect of the present disclosure causes a computer to perform the following functions: capturing an image of a living body; calculating a judgment index relating to the number of target pixels having pixel values ​​that are greater than or equal to a predetermined lower limit and less than or equal to a predetermined upper limit for a region of interest included in the image; and calculating biometric information from the pixel values ​​of pixels included in the region of interest whose judgment index is greater than or equal to a threshold value. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of a usage mode of a measurement device. [Diagram 2] FIG. 2 is a block diagram showing an example of the configuration of a measurement device. [Diagram 3] 4 is a flowchart showing an example of the operation of the measurement device according to the first embodiment. [Figure 4] 4 is a flowchart showing an example of the operation of the measurement device according to the first embodiment following FIG. 3. [Diagram 5] FIG. 13 is a diagram showing an example of target pixels and non-target pixels included in a region of interest. [Figure 6] FIG. 13 is a diagram illustrating a threshold value and a graph showing an example of a change in a determination index over time. [Figure 7] 13 is a flowchart showing an example of the operation of the measurement device according to the third embodiment. [Figure 8] 8 is a flowchart showing an example of the operation of the measurement device according to the second embodiment following FIG. 7. [Figure 9] 13 is a diagram showing a threshold value, a total use threshold value, and a graph showing an example of a change in a determination index over time. FIG. [Figure 10] FIG. 2 is a diagram showing an example of a plurality of regions of interest included in an image. [Figure 11] FIG. 2 is a diagram showing an example of multiple regions of interest contained within a region of interest. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First embodiment A first embodiment will be described with reference to Figures 1 to 6. In the drawings, the same or equivalent elements are given the same reference numerals, and duplicated explanations will be omitted.

[0010] 1 is a diagram showing an example of a usage mode of the measuring device 100. As shown in the example of FIG.

[0011] The measuring device 100 measures time-series changes on the surface and inside of the skin of a living body 102 from images acquired by an imaging unit 101, and acquires biological information. For example, the measuring device 100 is a PC (Personal Computer), a smartphone, a tablet terminal, a terminal dedicated to measuring biological information, a monitoring robot equipped with an imaging unit 101, etc. For example, the biological information is blood pressure, pulse rate, respiratory rate, blood oxygen saturation, etc.

[0012] The imaging unit 101 captures an image of a living body 102. In the present disclosure, a still image or a video cut out from a continuous or discontinuous actual recording showing a change in the volume of blood vessels of the living body 102 captured by the imaging unit 101 is referred to as an image.

[0013] The imaging unit 101 is installed at a position where it can capture an image of an exposed part of the body surface of the living body 102. The exposed part of the body surface of the living body 102 is the forehead, cheek, fingertips, wrist, palm, etc. of the living body 102. For example, the imaging unit 101 is installed in a PC, a display, a mirror, a washstand, etc.

[0014] The imaging unit 101 is a camera including a CCD (Charged Coupled Device), a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and a lens. The imaging unit 101 may be configured with an image sensor for a camera including RGB filters. For example, the imaging unit 101 includes a color filter in an RGB Bayer array in order to detect minute changes in the color of the skin of the living body 102. Alternatively, the imaging unit 101 may include color filters such as RGBCy and RGBIR. Color filters such as RGBCy and RGBIR are suitable for observing an increase or decrease in blood volume indicated by reflected light of light transmitted inside the skin.

[0015] 2 is a block diagram showing an example of the configuration of the measurement device 100. The measurement device 100 includes an imaging unit 101, an input unit 201, an output unit 202, a storage unit 203, a control unit 204, a determination index calculation unit 205, and a biological information calculation unit 206. The imaging unit 101, the input unit 201, the output unit 202, and the storage unit 203 are electrically connected to the control unit 204.

[0016] The imaging unit 101 captures an image of the living body 102 to obtain an image 211, and transmits the obtained image 211 to the control unit 204. For example, the imaging unit 101 captures an image of the living body 102 at 30 to 60 fps (frames per second) to obtain the image 211. The image 211 includes an image of the body surface of the living body 102.

[0017] The input unit 201 accepts input of information necessary for the measurement device 100. For example, the input unit 201 is a keyboard, a mouse, a touch panel, or the like.

[0018] The output unit 202 outputs the image 211, the biometric information 212, a message for the living body 102, the date and time, etc. For example, the output unit 202 is configured to include a display, a speaker, etc.

[0019] The storage unit 203 is a recording medium capable of recording various data, programs, etc., and is configured by, for example, a hard disk, an SSD (Solid State Drive), a semiconductor memory, etc. The storage unit 203 stores a predetermined lower limit value 213, a predetermined upper limit value 214, a threshold value 215, information related to the biometric information 212, changes over time in the biometric information 212, etc. The information related to the biometric information 212 is the type of the biometric information 212, a log of the biometric information 212 (such as daily changes), data for correcting information already stored in the storage unit 203, etc.

[0020] The control unit 204 executes various processes in accordance with the programs and data stored in the storage unit 203. The control unit 204 is configured with a processor such as a CPU (Central Processing Unit) and a GPU (Graphic Processing unit).

[0021] The control unit 204 includes a determination index calculation unit 205, a biological information calculation unit 206, and the like.

[0022] The judgment index calculation unit 205 calculates a judgment index 216 related to the number of target pixels TP having a pixel value that is equal to or greater than a predetermined lower limit value 213 and equal to or less than a predetermined upper limit value 214 for a region of interest included in the image 211. In the present disclosure, a pixel value is information indicating the brightness of a pixel included in the image 211, and is, for example, the pixel values ​​of sub-pixels for R (Red), G (Green), and B (Blue) in an RGB color space, the luminance value of a pixel in the RGB color space, or the values ​​of hue H (Hue), saturation S (Saturation), and brightness V (Value) calculated from the pixel values ​​of sub-pixels for R, G, and B in an HSV color space.

[0023] The biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of pixels included in a region of interest where the determination index 216 is equal to or greater than the threshold value 215. Specifically, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of a target pixel TP included in a region of interest where the determination index 216 is equal to or greater than the threshold value 215.

[0024] FIG. 3 is a flowchart showing an example of the operation of the measurement device 100 according to this embodiment.

[0025] In step S301, the imaging unit 101 captures an image of the living body 102 and acquires an image 211. When the output unit 202 is realized by a display, the control unit 204 causes the acquired image 211 to be displayed on the display.

[0026] In step S302, the determination index calculation unit 205 specifies a region of interest including an image of the body surface from the acquired image 211. For example, the determination index calculation unit 205 detects a face region of the living body 102 from the acquired image 211. Specifically, the determination index calculation unit 205 detects feature points such as the eyes, nose, and mouth from the image 211, and detects the face region based on the detected feature points. Then, the determination index calculation unit 205 specifies a region of interest including images of the forehead and cheeks of the living body 102 from the detected face region.

[0027] In step S303, the judgment index calculation unit 205 identifies one or more target pixels TP having a pixel value that is equal to or greater than the predetermined lower limit value 213 and equal to or less than the predetermined upper limit value 214 and that is included in the identified region of interest.

[0028] For example, the judgment index calculation unit 205 determines whether or not the pixel values ​​of the R sub-pixel, the G sub-pixel, and the B sub-pixel constituting a pixel included in the region of interest are equal to or greater than a predetermined lower limit value 213 and equal to or less than a predetermined upper limit value 214. Then, the judgment index calculation unit 205 specifies, as the target pixel TP, the pixel whose pixel value is equal to or greater than the predetermined lower limit value 213 and equal to or less than the predetermined upper limit value 214 for the R sub-pixel, the G sub-pixel, and the B sub-pixel.

[0029] For example, the predetermined lower limit value 213 has a value corresponding to the lower limit value of the dynamic range of the image 211, and the predetermined upper limit value 214 has a value corresponding to the upper limit value of the dynamic range of the image 211. Specifically, the predetermined lower limit value 213 has a value larger than the lower limit value of the dynamic range, and the predetermined upper limit value 214 has a value smaller than the upper limit value of the dynamic range.

[0030] For example, when a lower limit value, which is a pixel value corresponding to the lower limit of the dynamic range of RGB, is 0 and an upper limit value, which is a pixel value corresponding to the upper limit of the dynamic range of RGB, is 255, the predetermined lower limit value 213 is 1 and the predetermined upper limit value 214 is 254. In this case, the judgment index calculation unit 205 specifies, as the target pixel TP, a pixel included in the region of interest and having a pixel value of 1 or more and 254 or less. In this way, the judgment index calculation unit 205 can exclude a pixel with a pixel value of 0 that is a crushed black pixel and a pixel with a pixel value of 255 that is a blown out highlight pixel from the target pixel TP. Alternatively, the predetermined lower limit value 213 may be a value that is a predetermined value larger than the lower limit value of the dynamic range, and the predetermined upper limit value 214 may be a predetermined value smaller than the upper limit value of the dynamic range. For example, when the lower limit value of the dynamic range of RGB is 0 and the upper limit value of the dynamic range of RGB is 255, the predetermined lower limit value may be 10 and the predetermined upper limit value may be 244. In the following description, the upper and lower limits of the dynamic range are indicated by corresponding pixel values, but they are not limited to 256 gradations and 12-bit gradations may also be used.

[0031] In step S304, the judgment index calculation unit 205 calculates a judgment index 216 related to the number of pixels of the target pixel TP identified in step S303. For example, the judgment index calculation unit 205 calculates the ratio of the target pixel TP to all pixels in the region of interest as the judgment index 216. For example, it is assumed that the number of all pixels in the region of interest is 100, and the number of pixels having pixel values ​​equal to or greater than the predetermined lower limit value 213 and equal to or less than the predetermined upper limit value 214 is 80. In this case, the judgment index 216 is 80%. Alternatively, the judgment index calculation unit 205 may calculate the number of pixels of the target pixel TP as the judgment index 216.

[0032] In step S305, the biometric information calculation unit 206 determines whether or not the determination index 216 calculated in step S304 is equal to or greater than the threshold value 215. For example, when the determination index 216 indicates the proportion of the target pixel TP among all pixels in the region of interest and the threshold value 215 is 60%, the biometric information calculation unit 206 determines whether or not the proportion of the target pixel TP indicated by the determination index 216 is equal to or greater than 60%.

[0033] If the judgment index 216 is equal to or greater than the threshold 215 in step S305, the control unit 204 transitions the process to step S307. On the other hand, if the judgment index 216 is lower than the threshold 215 in step S305, the biological information calculation unit 206 determines the image 211 including the region of interest in which the judgment index 216 is lower than the threshold 215 as an unconditional image and registers it in the storage unit 203. For example, the judgment index calculation unit 205 registers the identification information of the image 211 including the region of interest in which the judgment index 216 is lower than the threshold 215 in the storage unit 203 as identification information of the unconditional image. For example, the identification information of the image 211 is a frame number. Then, the control unit 204 transitions the process to step S307.

[0034] In step S307, the biometric information calculation unit 206 determines whether or not the image 211 has been acquired for a predetermined time or a predetermined number of frames. The predetermined time or the predetermined number of frames is the time or the number of frames required to calculate the biometric information 212. The predetermined time or the predetermined number of frames may differ depending on the type of the biometric information 212.

[0035] If the images 211 have not been acquired for the predetermined time or the predetermined number of frames in step S307, the control unit 204 returns the process to step S301. On the other hand, if the images 211 have been acquired for the predetermined time or the predetermined number of frames in step S307, the control unit 204 transitions the process to step S401 illustrated in FIG.

[0036] Next, the operation of the measurement device 100 according to this embodiment will be further described with reference to FIG.

[0037] In step S401, the biometric information calculation unit 206 determines whether an unconditional image is registered. For example, the biometric information calculation unit 206 determines whether identification information of the unconditional image is registered in the storage unit 203. If the identification information of the unconditional image is not registered in the storage unit 203, the control unit 204 shifts the process to step S403. On the other hand, if the identification information of the unconditional image is registered in the storage unit 203, in step S402, the biometric information calculation unit 206 excludes an unconditional image to which identification information registered in the storage unit 203 is assigned from among a plurality of images or a predetermined number of frames acquired by capturing an image of the living body 102 for a predetermined time from the process of calculating the biometric information 212. Alternatively, the biometric information calculation unit 206 may exclude a moving image including an unconditional image to which identification information registered in the storage unit 203 is assigned from the process of calculating the biometric information 212. In other words, the biometric information calculation unit 206 judges an unconditional image including a region of interest whose judgment index 216 is lower than the threshold value 215, or a video including an unconditional image, to be a failed capture, and excludes the unconditional image or the video including the unconditional image from the process of calculating the biometric information 212.

[0038] In step S403, the biological information calculation unit 206 calculates a pulse wave signal indicating a pulse wave from a time change in pixel values ​​of pixels included in the region of interest where the judgment index 216 is equal to or greater than the threshold value 215. In the present disclosure, a pulse wave is a time series signal indicating a change in the volume of blood vessels, calculated from a time series signal indicating pixel values ​​of pixels included in the image 211 for the same position on the body surface.

[0039] For example, the biological information calculation unit 206 calculates a representative value of pixel values ​​of pixels included in a region of interest for which the judgment index 216 is equal to or greater than the threshold value 215. The biological information calculation unit 206 then calculates a pulse wave signal from a change over time in a value calculated by substituting the extracted pixel value or the representative value of the pixel value into a predetermined formula. Alternatively, the biological information calculation unit 206 may calculate a pulse wave signal from a change over time in pixel values ​​of pixels included in a region of interest for which the judgment index 216 is equal to or greater than the threshold value 215 using an independent component analysis method, a pigment component separation method, or the like.

[0040] In step S404, the biological information calculation unit 206 calculates biological information 212 according to the type of the biological information 212 to be calculated from the pulse wave signal calculated in step S403. For example, if the type of the biological information 212 to be calculated is a pulse rate, the biological information calculation unit 206 calculates the pulse rate based on the time required for one beat of the pulse wave indicated by the pulse wave signal. Also, for example, if the type of the biological information 212 to be calculated is blood pressure, the biological information calculation unit 206 estimates the blood pressure from the shape of the pulse wave signal.

[0041] In step S405, the biometric information calculation unit 206 causes the output unit 202 to output the biometric information 212 calculated in step S404.

[0042] For example, when the output unit 202 is configured to include a display, the biometric information calculation unit 206 displays characters, graphs, etc. indicating the pulse rate, blood pressure, etc. indicated by the biometric information 212 on the display. Furthermore, when the output unit 202 is configured to include a display, the biometric information calculation unit 206 may display a message for the living body 102, date and time, etc. on the display. For example, the message for the living body 102 indicates whether the pulse rate, blood pressure, etc. indicated by the biometric information 212 are within a predetermined range, such as "normal values." Alternatively, for example, when the output unit 202 is configured to include a speaker, a voice indicating the pulse rate, blood pressure, etc. indicated by the biometric information 212, a message for the living body 102, date and time, etc. may be output from the speaker.

[0043] 5 is a diagram showing an example of target pixels TP and non-target pixels NTP included in a region of interest 501. The non-target pixels NTP are pixels having pixel values ​​smaller than a predetermined lower limit value 213 or exceeding a predetermined upper limit value 214.

[0044] In the region of interest 501, the number of target pixels TP out of a total of 64 pixels is 34. Therefore, for example, when the determination index calculation unit 205 calculates the ratio of the target pixels TP out of all pixels in the region of interest as the determination index 216, the determination index calculation unit 205 calculates that the determination index 216 is 53.125% (=34 / 64).

[0045] FIG. 6 is a diagram showing the threshold value 215 and a graph 601 showing an example of a change over time in the determination index 216. In FIG. 6, the horizontal axis represents time, and the vertical axis represents the determination index. Each point shown in the graph 601 represents the determination index 216 for the region of interest included in the image 211 acquired at different time points. The determination index 216 for the region of interest included in the image 211 acquired from time t611 to time t612 and after time t613 is equal to or greater than the threshold value 215. Therefore, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the image 211 acquired from time t611 to time t612 and after time t613.

[0046] It should be noted that the relatively lower the threshold value 215, the more inappropriate pixels may be included. On the other hand, the relatively higher the threshold value 215, the less likely it is that the determination index 216 will be equal to or greater than the threshold value 215, and the longer the time required from when the image capture of the living body 102 is started until the living body information 212 is output. For this reason, it is preferable to set the threshold value 215 according to the pixel quality acceptable for the living body information 212 and the waiting time acceptable for the living body 102.

[0047] As described above, the measuring device 100 according to this embodiment calculates the biological information 212 from the time change in pixel values ​​within a preset range included in a region of interest included in an image 211 acquired by imaging a living body 102. As a result, the measuring device 100 according to this embodiment can calculate the biological information 212 while suppressing a decrease in the calculation accuracy of the biological information due to the adverse effect of inappropriate pixels having pixel values ​​outside the preset range.

[0048] (Modification 1 of the first embodiment) As a first modification of the measuring device 100 according to the present embodiment, the biological information calculation unit 206 may not calculate the biological information 212 until the judgment index 216 continues to be equal to or greater than the threshold value 215 for a predetermined time or a predetermined number of frames. Furthermore, in this modification, the imaging unit 101 may capture the living body 102 until the judgment index 216 continues to be equal to or greater than the threshold value 215. In this case, the biological information calculation unit 206 does not use the image 211 including the region of interest in which the judgment index 216 is lower than the threshold value 215 for the process of calculating the biological information 212. In this way, the biological information calculation unit 206 can calculate the biological information 212 from the time change in pixel value of the pixel included in the region of interest in which the judgment index 216 continues to be equal to or greater than the threshold value 215 for a predetermined time or a predetermined number of frames. Since biological information is reflected in the waveform of the pulse wave, it is more accurate to calculate the biological information by using a waveform that is continuous in time rather than a discontinuous waveform and using the entire waveform.

[0049] For example, it is assumed that the change over time of the judgment index 216 is shown by a graph 601 illustrated in FIG. 6. Furthermore, it is assumed that the judgment index 216 continues for a predetermined number of frames after time t613 and the judgment index 216 becomes equal to or greater than the threshold value 215. In this case, in this modification, the biometric information calculation unit 206 excludes the images 211 acquired from time t611 to time t612 from the process of calculating the biometric information 212. On the other hand, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the region of interest included in the images 211 acquired after time t613. In this way, the biometric information calculation unit 206 can use the images 211 acquired continuously for the process of calculating the biometric information 212. It is to be noted that whether or not the measuring device 100 according to this modification is adopted may be determined according to the waiting time allowed by the living body 102.

[0050] (Modification 2 of the first embodiment) As a second modification of the measuring apparatus 100 according to this embodiment, the determination index calculation unit 205 may use the average value, variance value, standard deviation value, etc. of the pixel values ​​of the target pixels TP included in the region of interest to calculate the determination index 216. For example, the determination index calculation unit 205 may calculate the determination index 216 based on the average value, variance value, standard deviation value, etc. of the pixel values ​​of the target pixels TP included in the region of interest and the number of the target pixels TP included in the region of interest.

[0051] Second Embodiment A second embodiment will be described. In the drawings, the same or equivalent elements are given the same reference numerals, and duplicated explanations will be omitted. Configurations and processes having substantially the same functions as other embodiments will be referred to by the same reference numerals, and explanations will be omitted, and differences from other embodiments will be described.

[0052] The predetermined lower limit value 213 and the predetermined upper limit value 214 according to this embodiment are set based on at least one of the RGB color space and the HSV color space. Specifically, the predetermined lower limit value 213 has a value based on at least one of the RGB color space and the HSV color space. Similarly, the predetermined upper limit value 214 has a value based on at least one of the RGB color space and the HSV color space.

[0053] For example, when the predetermined lower limit 213 is set based on the RGB color space, a predetermined lower limit r1 is set for the pixel value of the R subpixel, a predetermined lower limit g1 is set for the G subpixel, and a predetermined lower limit b1 is set for the B subpixel. In other words, when the predetermined lower limit 213 is set based on the RGB color space, the predetermined lower limit 213 is set for each of the R, G, and B subpixels.

[0054] When an image of a blemish, wrinkle, mole, etc. of the living body 102 is included in the region of interest, there is a possibility that the image of the blood vessel included in the region of interest and the image of the blemish, wrinkle, mole, etc. of the living body 102 are mixed. In that case, there is a possibility that appropriate biometric information 212 cannot be calculated from the time change of the pixel value of the pixel included in the region of interest. However, when the pixel value lower than the predetermined lower limit value r1, the predetermined lower limit value g2, and the predetermined lower limit value b3 is a value indicating the color of the image of the blemish, wrinkle, mole, etc. of the living body 102, the judgment index calculation unit 205 can exclude the pixel included in the image of the blemish, wrinkle, mole, etc. of the living body 102 included in the region of interest from the target pixel TP. This allows the biometric information calculation unit 206 to suppress deterioration of the calculation accuracy of the biometric information 212 due to inappropriate pixels.

[0055] Alternatively, when the predetermined lower limit 213 is set based on the RGB color space, the pixel value of a subpixel of one color and the pixel value of a subpixel of another color may be used to set the predetermined lower limit 213. For example, when |PixR(x,y)-PixG(x,y)|>m4, the judgment index calculation unit 205 judges a pixel including an R subpixel PixR(x,y) and a G subpixel PixG(x,y) to be the target pixel TP. PixR(x,y) indicates the R subpixel having coordinate values ​​x and y, PixG(x,y) indicates the G subpixel having coordinate values ​​x and y, and m4 indicates the predetermined lower limit 213.

[0056] Note that the predetermined lower limit value 213 and the predetermined upper limit value 214 may be different values ​​for each of the R sub-pixels, the G sub-pixels, and the B sub-pixels.

[0057] In addition, the pixel values ​​of R, G, and B shown in the RGB color space may vary greatly depending on the brightness of the surroundings when an object of the same color is captured. On the other hand, the hue, saturation, and brightness shown in the HSV color space are less affected by the brightness of the surroundings when the image is captured than the pixel values ​​of R, G, and B shown in the RGB color space. Therefore, when the brightness of the surroundings when the image is captured is likely to fluctuate, the determination index calculation unit 205 may determine the target pixel TP based on the hue, saturation, and brightness shown in the HSV color space. For example, when the predetermined lower limit value 213 and the predetermined upper limit value 214 are set based on the HSV color space, the predetermined lower limit value h1 and the predetermined upper limit value h2 for the hue, the predetermined lower limit value s1 and the predetermined upper limit value s2 for the saturation, and the predetermined lower limit value b1 and the predetermined upper limit value b2 for the brightness are set.

[0058] When the predetermined lower limit 213 and the predetermined upper limit 214 are set based on the HSV color space, the judgment index calculation unit 205 converts the pixel value of each pixel included in the region of interest from a value in the RGB color space to a value in the HSV color space. Then, the judgment index calculation unit 205 determines whether the pixel value indicating the converted value in the HSV color space is equal to or greater than the predetermined lower limit 213 and equal to or less than the predetermined upper limit 214.

[0059] By determining the target pixel TP based on the hue, saturation, and brightness indicated by the HSV color space, the judgment index calculation unit 205 can calculate the judgment index 216 while suppressing the influence of fluctuations in the surrounding brightness at the time of image capture.

[0060] Alternatively, the determination index calculation unit 205 may determine a target pixel TP having a pixel value that is equal to or greater than a predetermined lower limit value 213 corresponding to the RGB color space and equal to or less than a predetermined upper limit value 214 corresponding to the RGB color space, and equal to or greater than a predetermined lower limit value 213 corresponding to the HSV color space and equal to or less than a predetermined upper limit value 214 corresponding to the HSV color space. In this case, since the predetermined lower limit value 213 and the predetermined upper limit value 214 are values ​​corresponding to the color space, the value corresponding to the RGB color space and the value corresponding to the HSV color space may differ. Then, the determination index calculation unit 205 may calculate a determination index 216 related to the pixel number of the determined target pixel TP. By the predetermined lower limit value 213 and the predetermined upper limit value 214 having values ​​based on the RGB color space and the HSV color space, the determination index calculation unit 205 can more accurately select a target pixel TP having necessary information than when the predetermined lower limit value 213 and the predetermined upper limit value 214 have values ​​based on one color space.

[0061] Note that the color of the blood vessel image captured by the imaging unit 101 may be affected by the performance of the camera and the illuminance of the surrounding environment. Therefore, the range of pixel values ​​of the target pixel TP based on at least one of the RGB color space and the HSV color space may be set according to the performance of the camera and the illuminance of the surrounding environment.

[0062] Third embodiment The third embodiment will be described with reference to Figures 7 to 9. In the drawings, the same or equivalent elements are given the same reference numerals, and duplicated explanations are omitted. Configurations and processes having substantially the same functions as the other embodiments are referred to by the same reference numerals, and explanations are omitted, and differences from the other embodiments are described.

[0063] The configuration of the measurement device 100 according to this embodiment is as shown in Fig. 1. The biological information calculation unit 206 according to this embodiment calculates biological information 212 from the pixel values ​​of all pixels included in the region of interest in which the judgment index 216 is equal to or greater than the all-use threshold value that exceeds the threshold value 215.

[0064] Fig. 7 is a flowchart showing an example of the operation of the measurement device 100 according to this embodiment. The processes of steps S701 to S706 illustrated in Fig. 7 are similar to the processes of steps S301 to S306 illustrated in Fig. 3, and therefore detailed description thereof will be omitted.

[0065] In step S707, the determination index calculation unit 205 determines whether the determination index 216 is equal to or greater than the total use threshold. If the determination index 216 is not equal to or greater than the total use threshold in step S707, the control unit 204 transitions the process to step S709. On the other hand, if the determination index 216 is equal to or greater than the total use threshold in step S707, the determination index calculation unit 205 registers, in step S708, identification information of the image 211 including the region of interest to be determined in the storage unit 203 as identification information of all used regions of interest. Then, the control unit 204 transitions the process to step S709.

[0066] In step S709, the biological information calculation unit 206 determines whether or not the image 211 has been acquired for a predetermined time or a predetermined number of frames. The process of step S709 is similar to the process of step S307 illustrated in FIG. 3, and therefore a detailed description thereof will be omitted.

[0067] If the images 211 have not been acquired for the predetermined time or the predetermined number of frames in step S709, the control unit 204 returns the process to step S701. On the other hand, if the images 211 have been acquired for the predetermined time or the predetermined number of frames in step S709, the control unit 204 transitions the process to step S801 illustrated in FIG.

[0068] Next, the operation of the measurement device 100 according to this embodiment will be further described with reference to Fig. 8. The processes in steps S801 and S802 are similar to those in steps S401 and S402 illustrated in Fig. 4, and therefore will not be described in detail.

[0069] In step S803, the biological information calculation unit 206 calculates a pulse wave signal from the pixel values ​​of all pixels included in all used regions of interest and the time change in pixel value of the target pixel TP included in the region of interest in which the judgment index 216 is lower than the all-usage threshold and equal to or greater than the threshold 215. The all-used regions of interest are regions of interest included in the image 211 indicated by the identification information of all used regions of interest registered in step S708 illustrated in FIG. 7, and in which the judgment index 216 is equal to or greater than the all-usage threshold. Then, the control unit 204 proceeds to step S804. The processes in steps S804 to S805 are similar to those in steps S404 to S405 illustrated in FIG. 4, and therefore will not be described in detail.

[0070] For example, assume that the threshold value 215 is 60% and the total use threshold value is 70%. In this case, for a region of interest where the determination index 216 is 70% or more, the biometric information calculation unit 206 uses the pixel values ​​of all pixels included in the region of interest in the process of calculating the biometric information 212. Also, for a region of interest where the determination index 216 is 60% or more and lower than 70%, the biometric information calculation unit 206 uses the pixel value of the target pixel TP included in the region of interest in the process of calculating the biometric information 212.

[0071] Although the value of 70% is not limited to this, it is preferable to set the value such that the number of inappropriate pixels is small and the benefit of using a large number of pixels is greater than the adverse effect on the measurement. For example, when an average value of pixel values ​​of pixels in a region of interest is used to calculate biological information, even if the data acquired by the image sensor constituting the imaging unit 101 includes inappropriate pixels, the signal quality is improved by using many appropriate pixels, so that the signal-to-noise ratio is improved, and the calculation accuracy of the biological information is improved.

[0072] FIG. 9 is a diagram showing a graph 901 showing an example of a change over time in the thresholds, all used thresholds, and the determination index 216. In FIG. 9, the horizontal axis represents time, and the vertical axis represents the determination index. Each point on the graph 901 represents the determination index 216 for the region of interest included in each image 211. When the determination index 216 shown by the graph 901 is calculated, the biometric information calculation unit 206 uses the change over time in the pixel values ​​of all pixels in the region of interest included in each image 211 acquired from time t915 to time t916 and from time t919 to time t920 in the process of calculating the biometric information 212. For example, the biometric information calculation unit 206 uses the change over time in the pixel values ​​of all pixels in the region of interest included in each image 211 acquired from time t915 to time t916 and from time t919 to time t920 in the process of calculating the pulse wave signal.

[0073] Furthermore, when the determination index 216 indicated by the graph 901 is calculated, the biological information calculation unit 206 uses the time change in pixel value of the target pixel TP included in the region of interest for the images 211 acquired from time t911 to time t912, from time t913 to time t914, and from time t917 to time t918 in the process of calculating the biological information 212. For example, the biological information calculation unit 206 uses the time change in pixel value of the target pixel TP included in the region of interest for the images 211 acquired from time t911 to time t912, from time t913 to time t914, and from time t917 to time t918 in the process of calculating the pulse wave signal.

[0074] Therefore, the biological information calculation unit 206 uses the determination index 216 in the process of calculating the biological information 212 from the pixel values ​​of all pixels included in the region of interest where the determination index 216 is equal to or greater than the total use threshold. At this time, the number of inappropriate pixels is small compared to the number of appropriate pixels to the extent that the determination index 216 satisfies the total use threshold, so the accuracy improvement effect of using many appropriate pixels exceeds the deterioration of calculation accuracy caused by using an inappropriate image for calculation. As a result, the measurement device 100 according to this embodiment can calculate the biological information 212 using the pixel values ​​of many appropriate pixels, and therefore the calculation accuracy of the biological information 212 can be improved.

[0075] (Fourth embodiment) The fourth embodiment will be described with reference to Fig. 10. In the drawings, the same or equivalent elements are given the same reference numerals, and duplicated explanations are omitted. Configurations and processes having substantially the same functions as the other embodiments are referred to by the same reference numerals, and explanations are omitted, and differences from the other embodiments are described.

[0076] The configuration of a measuring device 100 according to this embodiment is as shown in FIG.

[0077] The determination index calculation unit 205 according to this embodiment calculates a determination index 216 for each of a plurality of regions of interest included in an image 211 .

[0078] The biometric information calculation unit 206 according to this embodiment calculates biometric information 212 from pixel values ​​of pixels included in a region of interest, among a plurality of regions of interest included in an image 211, where a determination index 216 is equal to or greater than a threshold value 215. Specifically, the biometric information calculation unit 206 calculates biometric information 212 from pixel values ​​of a target pixel TP included in a region of interest, among a plurality of regions of interest included in an image 211, where a determination index 216 is equal to or greater than a threshold value 215.

[0079] Alternatively, the biometric information calculation section 206 may calculate the biometric information 212 from the pixel value of the target pixel TP included in the region of interest having the largest determination index 216 among a plurality of regions of interest included in the image 211 .

[0080] Alternatively, the biometric information calculation unit 206 may calculate the biometric information 212 from the pixel values ​​of all pixels included in a region of interest in which the judgment index 216 is equal to or greater than the total use threshold value, among multiple regions of interest included in the image 211.

[0081] FIG. 10 is a diagram showing an example of a plurality of regions of interest included in an image 211. It is assumed that the pixels constituting the region 1011 included in the region of interest 1001, the pixel values ​​of the pixels constituting the region 1012 included in the region of interest 1002, the pixel values ​​of the pixels constituting the region 1013 included in the region of interest 1002, and the pixels constituting the region 1014 included in the region of interest 1003 are non-target pixels NTP. It is also assumed that the determination index 216 for the region of interest 1001 and the determination index 216 for the region of interest 1003 are equal to or greater than the threshold value 215. It is also assumed that the determination index 216 for the region of interest 1002 is lower than the threshold value 215. In this case, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the region of interest 1001 and the region of interest 1003. Here, the biometric information calculation unit 206 calculates the biometric information 212 by excluding the pixels constituting the region 1011 and the pixels constituting the region 1014 from the process of calculating the biometric information 212. In addition, in an image 211 different from the image 211 illustrated in FIG. 10, if the judgment index 216 is lower than the threshold value 215 for any of the regions of interest 1001 to 1003, the biometric information calculation unit 206 excludes the image 211 from the process of calculating the biometric information 212.

[0082] As described above, the measurement apparatus 100 according to this embodiment can calculate the biological information 212 from the pixel value of the target pixel TP included in a region of interest suitable for calculating the biological information 212, out of multiple regions of interest.

[0083] (Modification of the fourth embodiment) As a modification of the measuring apparatus 100 according to this embodiment, a plurality of regions of interest may be set within a region of interest by dividing the region of interest.

[0084] Fig. 11 is a diagram showing an example of a plurality of regions of interest included within a region of interest. The region of interest 1101 shown in Fig. 11 includes regions of interest 1111 to 1114. Regions of interest 1111 to 1114 are regions into which the region of interest 1101 is divided. Furthermore, the region of interest 1114 includes regions of interest 1121 to 1124. Regions of interest 1121 to 1124 are regions into which the region of interest 1114 is divided.

[0085] When the determination index 216 for the region of interest to be determined is lower than the threshold value 215, the determination index calculation unit 205 according to this modification calculates the determination index 216 for the multiple regions of interest into which the region of interest to be determined is divided. For example, when the determination index 216 for the region of interest 1101 is lower than the threshold value 215, the determination index calculation unit 205 calculates the determination index 216 for each of the regions of interest 1111 to 1114.

[0086] Furthermore, for example, when the determination index 216 is lower than the threshold value 215 for the regions of interest 1111 to 1114, the determination index calculation unit 205 calculates the determination index 216 for each of the multiple regions of interest into which the regions of interest 1111 to 1114 are divided. For example, the determination index calculation unit 205 calculates the determination index 216 for each of the regions of interest 1121 to 1124. In this manner, the determination index calculation unit 205 calculates the determination index 216 for each of the divided regions of interest of the determination target until the determination index 216 for the region of interest of the determination target that is equal to or larger than a predetermined size becomes equal to or larger than the threshold value 215.

[0087] Then, when the calculated determination index 216 for the divided region of interest of the determination target is equal to or greater than the threshold 215, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the divided region of interest of the determination target. That is, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the region of interest having a determination index 216 that is equal to or greater than a predetermined minimum size and equal to or greater than the threshold 215. For example, when the region of interest 1124 is equal to or greater than a predetermined size and the determination index 216 for the region of interest 1124 is equal to or greater than the threshold 215, the biometric information calculation unit 206 calculates the biometric information 212 from the pixel values ​​of the pixels included in the region of interest 1124.

[0088] Therefore, even if the judgment index 216 for a relatively large region of interest is lower than the threshold value 215, the biometric information calculation unit 206 in this modified example calculates the biometric information 212 from the pixel values ​​of the pixels included in the region of interest that is part of the region of interest and has the judgment index 216 equal to or greater than the threshold value 215.

[0089] As described above, the measurement device 100 according to this modified example can calculate the bio-information 212 from the pixel values ​​of the target pixels included in the region of interest within which the bio-information 212 can be calculated with high accuracy, even if the judgment index 216 for a relatively large region of interest is lower than the threshold value 215.

[0090] Fifth embodiment The fifth embodiment will be described. In the drawings, the same or equivalent elements are given the same reference numerals, and duplicated explanations are omitted. Configurations and processes having substantially the same functions as the other embodiments are referred to by the same reference numerals, and explanations are omitted, and differences from the other embodiments are described.

[0091] In the measurement device 100 according to this embodiment, at least one selected from the group consisting of the predetermined lower limit value 213, the predetermined upper limit value 214, and the threshold value 215 has a value according to the type of the biological information 212 that is the calculation target.

[0092] In the storage unit 203 according to this embodiment, a predetermined lower limit value 213, a predetermined upper limit value 214, and a threshold value 215 are stored in association with the type of biometric information 212 that is the calculation target.

[0093] For example, when the biometric information calculation unit 206 calculates a pulse rate, even if the pixels in the region of interest include relatively more pixels including unnecessary information other than blood vessels than when calculating blood pressure, the reliability of the calculated biometric information 212 tends to be satisfied. That is, when the type of the biometric information 212 is a pulse rate, the difference between the predetermined upper limit value 214 and the predetermined lower limit value 213 tends to be relatively larger than when the type of the biometric information 212 is blood pressure. Similarly, when the type of the biometric information 212 is a pulse rate, the threshold value 215 tends to be relatively lower than when the type of the biometric information 212 is blood pressure. That is, the range of pixel values ​​to be obtained and the required judgment index 216 differ depending on the type of biometric information to be calculated.

[0094] However, by storing in the storage unit 203 the predetermined lower limit value 213 and the predetermined upper limit value 214, which differ for each type of the biometric information 212 to be calculated, the determination index 216 can be calculated based on a criterion corresponding to the type of the biometric information 212. Furthermore, by storing in the storage unit 203 the threshold value 215, which differs for each type of the biometric information 212, the biometric information calculation unit 206 can determine the region of interest and the image 211 used to calculate the biometric information 212 based on the threshold value 215 corresponding to the type of the biometric information 212. In this way, the measuring device 100 can calculate the biometric information 212 from the pixel values ​​of the pixels included in the region of interest based on a criterion corresponding to the type of the biometric information 212.

[0095] Sixth Embodiment The sixth embodiment will be described. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and duplicated explanations will be omitted. Configurations and processes having substantially the same functions as the other embodiments will be denoted by the same reference numerals, and explanations will be omitted. Differences from the other embodiments will be described.

[0096] In the measurement device 100 according to this embodiment, at least one selected from the group consisting of the predetermined lower limit value 213 and the predetermined upper limit value 214 has a value corresponding to the color of the body surface associated with the type to which the living body 102 belongs. For example, the type to which the living body 102 belongs is the age, race, etc. of the living body 102.

[0097] For example, the color, saturation, brightness, etc. of the captured blood vessel image tend to differ depending on the age of the subject, such as infant, adolescent, middle-aged, elderly, etc. However, by storing a predetermined lower limit value 213 and a predetermined upper limit value 214 corresponding to the age in association with each other in the storage unit 203, the determination index calculation unit 205 can appropriately calculate the determination index 216 according to the age of the living body 102.

[0098] As described above, the measuring device 100 can determine the target pixel TP based on the type to which the living body 102 belongs by storing in the storage unit 203 the predetermined lower limit value 213 and the predetermined upper limit value 214, which differ for each type to which the living body 102 belongs. In this way, the measuring device 100 according to this embodiment can calculate the biological information 212 from the pixel value of the target pixel TP according to the age, race, etc. of the living body 102.

[0099] (Modification of the sixth embodiment) As a modified example of the measuring device 100 according to the present embodiment, at least one selected from the group consisting of the predetermined lower limit value 213 and the predetermined upper limit value 214 may have a value according to the color of the body surface associated with the type to which the living body 102 belongs, and the threshold value 215 may have a value according to the type of the biological information 212 to be calculated. In this case, the measuring device 100 according to this modified example can determine the target pixel TP based on a criterion according to the type to which the living body 102 belongs, and calculate the judgment index 216 based on a criterion according to the type of the biological information 212 to be calculated. As a result, the measuring device 100 according to this modified example can calculate the biological information 212 from the pixel values ​​of the pixels included in the region of interest based on the criterion according to the type to which the living body 102 belongs and the type of the biological information 212 to be calculated.

[0100] The processes executed in the above embodiments are not limited to the process modes exemplified in the above embodiments. The above-mentioned functional blocks may be realized using either a logic circuit (hardware) formed in an integrated circuit or the like, or software using a CPU. The processes executed in the above embodiments may be executed by multiple computers. For example, the processes executed in each functional block of the control unit 204 of the measuring device 100 may be partially executed by another computer, or all of the processes may be shared and executed by multiple computers.

[0101] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The technical scope of the present invention also includes embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Furthermore, new technical features can be formed by combining the technical means disclosed in the respective embodiments. [Explanation of symbols]

[0102] 100 Measuring device, 101 Imaging unit, 102 Living body, 201 Input unit, 202 Output unit, 203 Storage unit, 204 Control unit, 205 Judgment index calculation unit, 206 Biometric information calculation unit, 211 Image, 212 Biometric information, 213 Predetermined lower limit value, 214 Predetermined upper limit value, 215 Threshold value, 216 Judgment index, 501 Region of interest, 601 Graph, 901 Graph, 1001 to 1003 Regions of interest, 1011 to 1014 Regions, 1101 Regions of interest, 1111 to 1114 Regions of interest, 1121 to 1124 Regions of interest

Claims

1. an imaging unit that captures an image of a living body; a judgment index calculation unit that calculates a judgment index related to the number of target pixels having a pixel value that is equal to or greater than a predetermined lower limit value and equal to or less than a predetermined upper limit value and based on at least one of an RGB color space and an HSV color space, for a region of interest included in the image; a biological information calculation unit that calculates biological information from pixel values ​​of pixels included in a region of interest in which the determination index is equal to or greater than a threshold; Equipped with The predetermined lower limit value and the predetermined upper limit value are set according to the performance of the imaging unit and the illuminance of the surrounding environment. Measuring equipment.

2. the predetermined lower limit value has a value corresponding to a lower limit value of a dynamic range of the image, The predetermined upper limit has a value corresponding to the upper limit of the dynamic range.

2. The measuring device of claim 1.

3. The biological information calculation unit determines, as an imaging failure, an unconditional image including a region of interest in which the determination index is lower than the threshold value, or a moving image including the unconditional image.

3. The measuring device according to claim 1 or 2.

4. The biometric information calculation unit excludes the unconditional image or a video including the unconditional image from a process of calculating the biometric information.

4. The measuring device according to claim 3.

5. The biological information calculation unit calculates the biological information from pixel values ​​of all pixels included in a region of interest where the determination index is equal to or greater than a total use threshold that exceeds the threshold.

3. The measuring device according to claim 1 or 2.

6. The biological information calculation unit calculates the biological information from pixel values ​​of the target pixels included in a region of interest in which the determination index is equal to or greater than the threshold value.

3. The measuring device according to claim 1 or 2.

7. The determination index calculation unit calculates the determination index for each of a plurality of regions of interest included in the image; The biological information calculation unit calculates the biological information from pixel values ​​of pixels included in a region of interest in which the determination index is equal to or greater than the threshold value, among the plurality of regions of interest.

3. The measuring device according to claim 1 or 2.

8. the predetermined lower limit value has a value based on at least one of an RGB color space and an HSV color space, The predetermined upper limit value has a value based on at least one of the RGB color space and the HSV color space.

3. The measuring device according to claim 1 or 2.

9. The biological information calculation unit does not calculate the biological information until the determination index is equal to or greater than the threshold value for a predetermined time or a predetermined number of frames.

3. The measuring device according to claim 1 or 2.

10. The imaging unit captures an image of the living body until the determination index becomes equal to or greater than the threshold value.

3. The measuring device according to claim 1 or 2.

11. At least one selected from the group consisting of the predetermined lower limit value, the predetermined upper limit value, and the threshold value has a value corresponding to the type of the biological information.

3. The measuring device according to claim 1 or 2.

12. At least one selected from the group consisting of the predetermined lower limit value and the predetermined upper limit value has a value corresponding to a body surface color associated with the type to which the living body belongs.

3. The measuring device according to claim 1 or 2.

13. A step of capturing an image of a living body by an imaging unit to obtain an image; calculating a judgment index for the number of target pixels having pixel values ​​that are equal to or greater than a predetermined lower limit and equal to or less than a predetermined upper limit, and that are based on at least one of an RGB color space and an HSV color space, for a region of interest included in the image; calculating biological information from pixel values ​​of pixels included in a region of interest where the determination index is equal to or greater than a threshold; Including, In the step of calculating the biological information, the predetermined lower limit value and the predetermined upper limit value are set according to the performance of the imaging unit and the illuminance of the surrounding environment. Measurement method.

14. On the computer, A function of capturing an image of a living body by an imaging unit to obtain an image; A function of calculating a judgment index relating to the number of target pixels having pixel values ​​that are equal to or greater than a predetermined lower limit and equal to or less than a predetermined upper limit, and based on at least one of an RGB color space and an HSV color space, for a region of interest included in the image; a function of calculating biological information from pixel values ​​of pixels included in a region of interest in which the determination index is equal to or greater than a threshold; Run the command, In the function of calculating the biological information, the predetermined lower limit value and the predetermined upper limit value are set according to the performance of the imaging unit and the illuminance of the surrounding environment. program.

15. an imaging unit that captures an image of a living body; a determination index calculation unit that calculates a determination index relating to the number of target pixels having a pixel value that is equal to or greater than a predetermined lower limit value and equal to or less than a predetermined upper limit value for a region of interest included in the image; a biological information calculation unit that calculates biological information from pixel values ​​of pixels included in a region of interest in which the determination index is equal to or greater than a threshold; Equipped with The biological information calculation unit calculates the biological information from pixel values ​​of all pixels included in a region of interest where the determination index is equal to or greater than a total use threshold that exceeds the threshold. Measuring equipment.

16. A step of capturing an image of a living body; calculating a judgment index relating to the number of target pixels having pixel values ​​that are equal to or greater than a predetermined lower limit and equal to or less than a predetermined upper limit for a region of interest included in the image; calculating biological information from pixel values ​​of pixels included in a region of interest where the determination index is equal to or greater than a threshold; Including, In the step of calculating the biological information, the biological information is calculated from pixel values ​​of all pixels included in a region of interest where the determination index is equal to or greater than a total use threshold that exceeds the threshold. Measurement method.

17. On the computer, A function of capturing an image of a living body; A function of calculating a judgment index related to the number of target pixels having a pixel value that is equal to or greater than a predetermined lower limit value and equal to or less than a predetermined upper limit value for a region of interest included in the image; a function of calculating biological information from pixel values ​​of pixels included in a region of interest in which the determination index is equal to or greater than a threshold; Run the command, In the function of calculating the biological information, the biological information is calculated from pixel values ​​of all pixels included in a region of interest where the determination index is equal to or greater than a total use threshold that exceeds the threshold. program.

Images