Information processing device, information processing method, and program

Abstract

An information processing device (100) evaluates a hair suppression effect by an optical hair removal device (10). The information processing device (100) comprises: an acquisition unit (111) for acquiring a skin image capturing a target part of a subject; a counting unit (112) for counting the number of body hairs from a skin image (200); and an evaluation unit (113) for evaluating the hair suppression effect on the basis of a result of comparison between a first counting result, which is the result of counting with respect to a first skin image captured at a first timing, and a hair amount prediction value at the first timing which is based on a second counting result that is the result of counting with respect to a second skin image captured at a second timing that is one period prior to the first timing.

Description

Information processing device, information processing method, and program

[0001] The present disclosure relates to an information processing device, an information processing method, and a program.

[0002] Patent Document 1 discloses a measurement system that counts the number of body hairs and evaluates hair removal or hair growth.

[0003] Japanese Patent Application Laid-Open No. 2021-56708

[0004] The present disclosure provides an information processing device and the like that can appropriately evaluate the hair growth suppression effect of a photoepilation device.

[0005] An information processing device according to one aspect of the present disclosure is an information processing device that evaluates the hair suppression effect of an optical hair removal device, and includes: an acquisition unit that acquires a skin image of a target area of ​​a subject; a counting unit that counts the number of body hairs from the skin image; and an evaluation unit that evaluates the hair suppression effect based on a comparison result between a first counting result that is the result of the counting for a first skin image taken at a first timing and a predicted hair volume value at the first timing based on a second counting result that is the result of the counting for a second skin image taken at a second timing that is one period before the first timing.

[0006] In addition, an information processing method according to one aspect of the present disclosure is an information processing method executed by an information processing device having one or more processors and evaluating the hair suppression effect of an optical hair removal device, wherein the one or more processors acquire a skin image of a target area of ​​a subject, count the number of body hairs from the skin image, and evaluate the hair suppression effect based on a comparison result between a first counting result which is the counting result for a first skin image taken at a first timing and a predicted hair volume value at the first timing based on a second counting result which is the counting result for a second skin image taken at a second timing one period before the first timing.

[0007] These general or specific aspects may be realized by a device, an integrated circuit, a computer program, or a non-transitory recording medium such as a computer-readable CD-ROM, or by any combination of a device, an integrated circuit, a computer program, and a non-transitory recording medium.

[0008] The information processing device and the like according to the present disclosure can appropriately evaluate the hair growth suppression effect of the photo-epilation device.

[0009] FIG. 1 is a diagram illustrating an overview of an information processing device according to an embodiment. FIG. 2 is a hardware configuration diagram of the information processing device according to the embodiment. FIG. 3 is a block diagram illustrating an example of the functional configuration of the information processing device according to the embodiment. FIG. 4 is a diagram illustrating a process for setting a region to be counted in a skin image. FIG. 5 is a diagram illustrating a process for calculating a constant for determining a threshold for binarizing a skin image. FIG. 6 is a diagram illustrating luminance values ​​used for binarizing a skin image. FIG. 7 is a diagram illustrating a process for determining pixels that are candidates for body hair when binarizing a skin image. FIG. 8 is a diagram illustrating a process for determining pixels other than candidates for body hair when binarizing a skin image. FIG. 9 is a graph illustrating the relationship between a second average luminance and a threshold for determining pixels that are candidates for body hair. FIG. 10 is a diagram illustrating an example of a binarized image. FIG. 11 is a diagram illustrating an example of a method for detecting a pixel group. FIG. 12 is a diagram illustrating an example of a pixel group of a cluster of pixels that are candidates for body hair in a binarized image. FIG. 13 is a diagram illustrating an example of a rectangle surrounding a pixel group. FIG. 14 is a diagram illustrating a process for identifying the length of body hair. Fig. 15 is a diagram showing an example of heat map data. Fig. 16 is a diagram showing an example of display information. Fig. 17 is a diagram showing an example of processing for detecting hair volume by capturing a skin image at a second timing (e.g., the first time). Fig. 18 is a flowchart showing details of counting processing. Fig. 19 is a diagram showing an example of processing for detecting hair volume by capturing a skin image at a first timing (e.g., the second time or later).

[0010] (Findings underlying the present disclosure) Human body hair grows in a regular cycle called the hair cycle. The hair cycle includes a growth phase, a regressive phase, and a telogen phase, and body hair repeats these phases. Body hair grows during the growth phase, then degenerates during the regressive phase, and transitions to the telogen phase. When new body hair is generated within the same hair follicle, the body hair in the telogen phase falls out. As such, the hair cycle includes a period when body hair grows and a period when body hair does not grow. Therefore, it is difficult to distinguish whether body hair does not grow due to the hair growth inhibition effect or because body hair is in the telogen phase. Therefore, in order to evaluate the hair growth inhibition effect of a photoepilation device, it is necessary to wait a period based on the hair cycle after treatment with the photoepilation device.

[0011] In addition, the hair growth suppression effect varies depending on the individual and the area treated. Therefore, the change due to the hair growth suppression effect may not be noticeable to the naked eye but may appear gradually. For this reason, it is necessary to display to the user whether or not the hair growth suppression effect of the photoepilation device is being observed.

[0012] The technology of Patent Document 1 quantitatively evaluates hair loss or hair growth by measuring the number of body hairs.

[0013] However, with the technology of Patent Document 1, it is not possible to determine whether the hair growth suppression effect of the photoepilation device is being properly achieved, making it difficult for the user to decide whether to continue the treatment without adjusting the output magnitude of the photoepilation device or to adjust the output magnitude and continue the treatment. In other words, with the conventional technology, it is difficult to properly set the output of the photoepilation device, which can lead to the problem that the output is too high for the user, causing unnecessary damage to the skin, or the output is too low, resulting in an inability to obtain a proper hair growth suppression effect.

[0014] In order to solve these problems, the present inventors have come up with an information processing device and the like that can appropriately evaluate the hair growth suppression effect of a photo-epilation device.

[0015] An information processing device according to a first aspect of the present disclosure is an information processing device that evaluates the hair suppression effect of an optical hair removal device, and includes an acquisition unit that acquires a skin image of a target area of ​​a subject, a counting unit that counts the number of body hairs from the skin image, and an evaluation unit that evaluates the hair suppression effect based on a comparison result between a first counting result that is the result of the counting for a first skin image taken at a first timing and a predicted hair volume value at the first timing based on a second counting result that is the result of the counting for a second skin image taken at a second timing that is one period before the first timing.

[0016] According to this, the first counting result for the first skin image at the first timing is compared with the predicted hair volume value predicted based on the hair growth suppression effect of the treatment with the photo-epilation device at the timing corresponding to the second timing, so it is possible to determine whether the predicted hair growth suppression effect has been achieved, thereby enabling the hair growth suppression effect of the photo-epilation device to be appropriately evaluated.

[0017] An information processing device according to a second aspect of the present disclosure is the information processing device according to the first aspect, wherein the first timing is a timing a second period after a treatment is performed by the optical hair removal device, and the second timing is a timing the second period after a treatment is performed after the treatment by the optical hair removal device.

[0018] Therefore, both the first timing and the second timing can be set to a timing that is a second period after the corresponding treatment is performed, so that the hair growth suppression effect can be evaluated with reduced error due to the amount of body hair growth.

[0019] An information processing device according to a third aspect of the present disclosure is an information processing device according to the first or second aspect, wherein when the absolute value of the value obtained by subtracting the first counting result from the predicted hair volume value is equal to or less than a predetermined threshold, the evaluation unit calculates an evaluation value indicating the hair suppression effect based on the difference between the first counting result and the predicted hair volume value, and outputs the calculated evaluation value.

[0020] According to this, if the absolute value of the value obtained by subtracting the first counting result from the predicted hair volume value is less than or equal to a predetermined threshold value, it can be determined that an appropriate first counting result has been obtained, and an appropriate evaluation value can be calculated.

[0021] An information processing device according to a fourth aspect of the present disclosure is an information processing device according to any one of the first to third aspects, wherein the evaluation unit outputs presentation information prompting the subject to take a new skin image of the subject when the evaluation value is greater than a predetermined threshold value.

[0022] According to this, if the evaluation value is greater than a predetermined threshold, it can be determined that the photographing has failed, and an appropriate first counting result can be obtained by prompting the user to photograph again.

[0023] An information processing device according to a fifth aspect of the present disclosure is an information processing device according to any one of the first to fourth aspects, wherein the counting unit (i) extracts the outline of each of a plurality of body hairs in the skin image, (ii) sets a rectangle that surrounds the extracted outline and has the smallest area, and counts the number of one or more rectangles among the set rectangles, the length of at least one of the long and short sides of which is within a predetermined range, as the number of body hairs.

[0024] This makes it possible to exclude counting areas other than body hair, such as skin wrinkles, pores, and moles, and therefore to properly count body hair.

[0025] An information processing device according to a sixth aspect of the present disclosure is an information processing device according to the fifth aspect, wherein the counting unit sets a target area in the skin image between the nose and upper lip of the subject's face as a target for detecting body hair, and sets the multiple rectangles within the target area.

[0026] Therefore, whiskers as body hair growing on a person's face can be counted appropriately.

[0027] An information processing device according to a seventh aspect of the present disclosure is an information processing device according to any one of the first to sixth aspects, and further includes a calculation unit that divides a skin region that is the region of the target part in the skin image into a plurality of divided regions and calculates the hair density for each of the plurality of divided regions, a generation unit that generates heat map data of the hair density in the skin region based on the calculation results by the calculation unit, and an output unit that outputs display information for displaying the first heat map data obtained from the first skin image and the second heat map data obtained from the second skin image in a state that allows them to be compared.

[0028] This makes it possible to visualize the distribution of body hair density.

[0029] An information processing method according to an eighth aspect of the present disclosure is an information processing method executed by an information processing device having one or more processors and evaluating the hair suppression effect of an optical hair removal device, wherein the one or more processors acquire a skin image of a target area of ​​a subject, count the number of body hairs from the skin image, and evaluate the hair suppression effect based on a comparison result between a first counting result which is the counting result for a first skin image taken at a first timing and a predicted hair volume value at the first timing based on a second counting result which is the counting result for a second skin image taken at a second timing one period before the first timing.

[0030] According to this, the first counting result for the first skin image at the first timing is compared with the predicted hair volume value predicted based on the hair growth suppression effect of the treatment with the photo-epilation device at the timing corresponding to the second timing, so it is possible to determine whether the predicted hair growth suppression effect has been achieved, thereby enabling the hair growth suppression effect of the photo-epilation device to be appropriately evaluated.

[0031] A program according to a ninth aspect of the present disclosure is a program for causing a computer to execute the information processing method according to the eighth aspect.

[0032] These general or specific aspects may be realized by a device, an integrated circuit, a computer program, or a non-transitory recording medium such as a computer-readable CD-ROM, or by any combination of a device, an integrated circuit, a computer program, and a non-transitory recording medium.

[0033] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of well-known matters or redundant explanation of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0034] The inventors have provided the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims.

[0035] (Embodiment) [Configuration] FIG. 1 is a diagram for explaining an overview of an information processing device according to an embodiment.

[0036] The information processing device 100 is a device for evaluating the hair growth suppression effect of the photo-epilation device 10. The photo-epilation device 10 is a device that irradiates skin with intense pulsed light (IPL). This allows the photo-epilation device 10 to damage hair matrix cells or hair papillae of the skin irradiated with IPL. This provides a hair growth suppression effect that inhibits body hair growth.

[0037] For example, a user (subject) may shave body hair (e.g., facial hair) on a target area with a razor or electric shaver, and then use the photo-epilation device 10 to irradiate the skin with IPL light. The treatment is performed immediately after shaving. In other words, the shaving and treatment are approximately the same and correspond to each other.

[0038] Then, the user photographs the treatment area using the information processing device 100 a second time period (e.g., 1 to 1.5 days) after the treatment. The reason why the second time period is set to 1 to 1.5 days is that 0.5 days after shaving, there is body hair that has not yet emerged from the skin surface, making it difficult to detect growing body hair from the skin image, and after two days or more, body hair begins to intersect with nearby body hair, making it difficult to count the body hair. In other words, when the second time period is 1 to 1.5 days, it is easy to detect and count growing body hair from the skin image.

[0039] The user repeats treatment with the photo-epilation device 10 and image capture with the information processing device 100 at a cycle of a first period. As a result, a plurality of skin images captured at a plurality of different times are stored in the information processing device 100. The first period is, for example, two to eight weeks. The information processing device 100 evaluates the hair growth suppression effect of the photo-epilation device by performing image processing on the plurality of skin images captured at a plurality of different times.

[0040] The first period may be set to a different period based on the amount of time that has elapsed since the start of treatment using the photo-epilation device 10. For example, the first period may be set to two weeks when the elapsed time is between 0 and 2 months, and may be set to four to eight weeks when the elapsed time is three months or more. In this way, the first period may be set so that the longer the elapsed time, the longer the first period.

[0041] FIG. 2 is a diagram showing the hardware configuration of the information processing device according to the embodiment.

[0042] As shown in FIG. 2, the information processing device 100 includes, as its hardware configuration, a processor 101, a main memory 102, a storage 103, a communication IF (Interface) 104, an input device 105, a display 106, and a camera 107.

[0043] The processor 101 is a processor that executes a program stored in the storage 103 or the like.

[0044] The main memory 102 is a volatile storage area that is used to temporarily store data generated during processing by the processor 101, used as a work area used when the processor 101 executes a program, and used to temporarily store data received by the communication IF 104.

[0045] The storage 103 is a non-volatile storage area that holds various data such as programs, etc. The storage 103 stores, for example, various data generated as a result of processing by the processor 101 and various data received by the communication IF 104.

[0046] The communication IF 104 is a communication interface for transmitting and receiving information to and from other information processing devices via a network (not shown). The communication IF 104 may be, for example, an interface for wireless communication such as a wireless LAN interface or a Bluetooth (registered trademark) interface. The communication IF 104 may also be an interface for wired communication such as a USB (Universal Serial Bus) or a wired LAN interface.

[0047] The input device 105 is an interface for receiving input from a person. The input device 105 may be a pointing device such as a mouse, a touchpad, a touch panel, or a trackball, or may be a keyboard.

[0048] The display 106 is a liquid crystal display, an organic EL display, or the like.

[0049] The camera 107 captures an image of a subject and generates an image including the subject. The camera 107 may be a color camera (RGB camera) or a monochrome camera.

[0050] The information processing device 100 may be, for example, a mobile terminal such as a smartphone or a tablet terminal, or may be a PC (Personal Computer).

[0051] FIG. 3 is a block diagram illustrating an example of a functional configuration of the information processing device according to the embodiment.

[0052] 3 , the information processing device 100 includes, as functional components, an acquisition unit 111, a counting unit 112, an evaluation unit 113, a calculation unit 114, a generation unit 115, an output unit 116, and a storage unit 117. The information processing device 100 does not necessarily have to include the calculation unit 114, the generation unit 115, and the output unit 116.

[0053] The acquisition unit 111 acquires a skin image of a target area of ​​the user (subject). The acquisition unit 111 acquires the skin image by capturing an image of the target area. The acquisition unit 111 acquires a skin image each time an image is captured. That is, the acquisition unit 111 may acquire a plurality of skin images captured at a plurality of different times. The acquisition unit 111 acquires a plurality of skin images each time a skin image is captured, and therefore acquires each skin image at a different time. The skin images acquired by the acquisition unit 111 are output to the counting unit 112 and the storage unit 117. The acquisition unit 111 is realized by, for example, the camera 107.

[0054] The counting unit 112 executes a counting process to count the number of body hairs from the skin image. Each time a skin image is acquired by the acquisition unit 111, the counting unit 112 executes the counting process for the acquired skin image. That is, the counting unit 112 executes the counting process for each of the multiple skin images. The counting unit 112 is realized by, for example, the processor 101, the main memory 102, the storage 103, etc.

[0055] The evaluation unit 113 compares a first counting result, which is the result of the counting process on the first skin image, with a hair volume prediction value based on a second counting result, which is the result of the counting process on the second skin image. The first skin image is a skin image from among the multiple skin images, which is generated by the acquisition unit 111 at a first timing. That is, the first skin image is a skin image captured at the first timing. The second skin image is a skin image from among the multiple skin images, which is generated by the acquisition unit 111 at a second timing. That is, the second skin image is a skin image captured at the second timing. The second timing is a timing one period before the first timing. The first timing is a timing two periods after a treatment using the photo-epilation device 10 is performed. The second timing is a timing two periods after a treatment following the treatment using the photo-epilation device 10 (the treatment performed two periods before the first timing).

[0056] The predicted hair volume value is a predicted value of the hair volume at the first timing calculated based on the second counting result obtained from the second skin image captured at the second timing. In other words, the predicted hair volume value is the hair volume (number of body hairs) at the first timing that is predicted to decrease due to the hair growth suppression effect expected from the treatment at the timing corresponding to the second timing. For example, the predicted hair volume value is calculated by multiplying the second counting result by a first rate (e.g., 85%) that is smaller than 1. The predicted hair volume value is calculated assuming that the second counting result will decrease at a predetermined rate (e.g., 15%). The predetermined rate of decrease is a value obtained by subtracting the first rate from 1.

[0057] The predicted hair volume value may be calculated taking into account the frequency of treatment. In this case, the first ratio used to calculate the predicted hair volume value may be determined to be smaller as the frequency of treatment increases.

[0058] The first counting result is the number of hairs contained in the target area of ​​the first skin image, and the second counting result is the number of hairs contained in the target area of ​​the second skin image. The first skin image is an image of the target area of ​​the user captured at a first timing, and the second skin image is an image of the target area captured at a second timing. In other words, the first skin image and the second skin image have in common that they capture the same target area of ​​the user. The first counting result and the second counting result also have in common that they indicate the number of hairs in the target area. The predicted hair volume value is calculated by multiplying the number of hairs contained in the second skin image by a first ratio, and therefore indicates the predicted number of hairs.

[0059] The evaluation unit 113 then evaluates the hair growth suppression effect based on the comparison result between the first counting result and the predicted hair volume value. If the comparison result between the first counting result and the predicted hair volume value indicates that the first counting result and the predicted hair volume value are close to each other, the evaluation unit 113 calculates an evaluation value indicating the hair growth suppression effect based on the difference between the first counting result and the predicted hair volume value, and outputs the calculated evaluation value. The difference between the first counting result and the predicted hair volume value may be, for example, the absolute value (i.e., the difference) of the difference between the predicted hair volume value and the first counting result. The difference between the first counting result and the predicted hair volume value may also be the ratio (i.e., the ratio) of the first counting result to the predicted hair volume value. The first counting result and the predicted hair volume value may be determined to be close to each other if the absolute value of the value obtained by subtracting the first counting result from the predicted hair volume value is equal to or less than the first number, or if the ratio of the first counting result to the predicted hair volume value is within a range of ±second ratio.

[0060] The evaluation value may be the calculated difference itself, or may be a value correlated with the magnitude of the difference. If the difference is a differential, the evaluation value may be calculated so that the smaller the difference, the higher the evaluation. If the difference is a ratio, the evaluation value may be calculated so that the closer the ratio is to 1, the higher the evaluation. In other words, the evaluation value is calculated so that the closer the first counting result is to the predicted hair volume value, the higher the evaluation.

[0061] Furthermore, if the absolute value of the difference between the first counting result and the predicted hair volume value (hereinafter simply referred to as the "absolute value") is greater than a predetermined threshold, the evaluation unit 113 outputs presentation information urging the user to capture a new skin image of the user (i.e., re-capture). For example, the absolute value being greater than the predetermined threshold may occur when the first counting result (i.e., the number of hairs detected from the first skin image) is greater than the predicted hair volume value (i.e., the number of hairs detected from the second skin image) by a second number or more. The second number is a value greater than the first number. The evaluation unit 113 may output the presentation information by, for example, displaying it on the output unit 116. The presentation information may include, for example, a message urging the user to re-capture the skin image. In this way, by displaying the presentation information on the information processing device 100, the user can be urged to re-capture the skin image of the user using the information processing device 100.

[0062] The reason why the system prompts the user to retake a photo when the absolute value is greater than the predetermined threshold is as follows: considering that the photo-epilation device 10 is exerting a hair growth suppression effect, it is expected that the amount of hair will be less at the first timing than at the second timing, but the absolute value is greater than the predetermined threshold, i.e., the first counting result is greater than the predicted hair amount by at least the second number. In other words, when the absolute value is greater than the predetermined threshold, it is presumed that this is due to a failed photo-taking attempt.

[0063] The calculation unit 114 divides a skin region, which is a region of a target part in the skin image, into a plurality of divided regions, and calculates the body hair density for each of the plurality of divided regions.

[0064] The generating unit 115 generates heat map data of the hair density in the skin region based on the calculation result by the calculating unit 114 .

[0065] The output unit 116 outputs display information for displaying the first heat map data obtained from the first skin image and the second heat map data obtained from the second skin image in a state where they can be compared. The output unit 116 outputs the display information by displaying it. The output unit 116 may output the display information by transmitting it to another information processing device. In this case, when the other information processing device receives the display information from the information processing device 100, the other information processing device may display the received display information on a display provided in the other information processing device.

[0066] The storage unit 117 stores the multiple skin images acquired by the acquisition unit 111. The storage unit 117 may store the skin images together with time information indicating the timing at which the skin images were captured. The storage unit 117 stores the multiple skin images each time each skin image is acquired. The time information may indicate an absolute time or a relative time from a predetermined reference time, as long as it indicates the timing at which the skin image was captured. The storage unit 117 may also store the counting result by the counting unit 112 each time the counting unit 112 performs a count.

[0067] [Details of Counting Process] Next, the details of the counting process by the counting unit 112 will be described with reference to FIGS.

[0068] 4A and 4B are diagrams illustrating a process for setting a region to be counted in a skin image. Fig. 4A shows a skin image 200 including the entire face of a user, and Fig. 4B is an enlarged view of a region A1 in the skin image 200 including the area around the user's mouth.

[0069] The counting unit 112 sets a target region 207, in which body hair is to be detected, between the nose and upper lip of the user's face in the skin image 200. That is, the counting unit 112 detects body hair from the target region 207. On the other hand, the counting unit 112 does not detect body hair from regions other than the target region 207.

[0070] To set the target region 207, the counting unit 112 detects a plurality of feature points 201 to 206 on the user's face in the skin image 200, and sets a plurality of straight lines L1 to L3 and a broken line L4 that pass through the plurality of feature points 201 to 206. Then, the counting unit 112 sets the region surrounded by the plurality of straight lines L1 to L3 and the broken line L4 as the target region 207.

[0071] Two feature points 201 correspond to the positions of the corners of the user's eyes. Feature point 202 corresponds to the center position in the horizontal direction of the bottom tip of the user's nose. Two feature points 203 correspond to the positions of both ends of the user's lips in the horizontal direction. Two feature points 204 and 206 correspond to the peaks of the user's upper lip. Feature point 205 corresponds to the center position in the horizontal direction of the user's upper lip.

[0072] One of the two straight lines L1 is a straight line that passes through the feature points 201 and 203 that are located on the left side of the face, of the two feature points 201 and 203, and the other is a straight line that passes through the feature points 201 and 203 that are located on the right side of the face, of the two feature points 201 and 203. The straight line L2 is a straight line that passes through the feature point 202 and extends in the left-right direction. The straight line L3 is a straight line that passes through the two feature points 203. The broken line L4 is a broken line that includes multiple line segments that connect two adjacent feature points among the feature points 203 to 206. The multiple line segments include a line segment that connects the feature points 203 and 204 on the right side of the lips, a line segment that connects the feature points 204 and 205, a line segment that connects the feature points 205 and 206, and a line segment that connects the feature point 206 and the feature point 203 on the left side of the lips.

[0073] The target region 207 may be, for example, a region surrounded by two straight lines L1, L2, and L4 out of the multiple straight lines L1 to L3 and the broken line L4. In this case, the straight line L3 does not need to be set. Furthermore, the target region 207 is not limited to the above-mentioned region, but may be, for example, a region surrounded by two straight lines L1, L2, and L3 out of the multiple straight lines L1 to L3 and the broken line L4. In this case, the broken line L4 does not need to be set, and the feature points 204 to 206 do not need to be detected.

[0074] Next, the counting unit 112 binarizes the skin image to detect body hair. Specifically, the counting unit 112 binarizes the skin image by setting a pixel value of 1 to pixels in the skin image that are candidates for body hair and setting a pixel value of 0 to other pixels. Note that the values ​​set as pixel values ​​during binarization are not limited to 0 and 1, and other values ​​may also be set. Furthermore, the counting unit 112 may set the pixel value of pixels that are candidates for body hair to 0 and the pixel value of other pixels to 1.

[0075] FIG. 5 is a diagram for explaining the process of calculating a constant for determining a threshold value in binarizing a skin image.

[0076] The counting unit 112 sets a plurality of blocks 210 in the target region 207. Fig. 5 shows an example in which a plurality of blocks 210 are set in a region 208 that is a part of the target region 207. The following description will be given using the region 208 as an example.

[0077] The multiple blocks 210 are set by dividing the region 208. In FIG. 5 , the region 208 is divided into 7×9 blocks 210. Each of the multiple blocks 210 may be, for example, a 32×32 block with a vertical size of 32 pixels and a horizontal size of 32 pixels. Note that the size of the blocks 210 is not limited to the above and may be another size, such as a 16×16 block. For each of the multiple blocks 210, the counting unit 112 calculates a constant c corresponding to a first average luminance, which is the average of the luminance values ​​of the 32×32 pixels in the block 210, and sets the constant c for the block 210. The constant c is used to determine a threshold Th for binarizing the skin image. The constant c is calculated, for example, based on relationship information indicating the relationship between the first average luminance and the constant c. The relationship information may be represented, for example, as a table or a relational equation. The relationship indicated by the relationship information is, for example, a relationship in which the constant c increases as the first average luminance increases. The relationship information is stored in the storage unit 117. The counting unit 112 reads out the relationship information from the storage unit 117, and calculates the constant c using the first average luminance and the relationship indicated by the read-out relationship information.

[0078] Fig. 6 is a diagram for explaining luminance values ​​used in binarizing a skin image, Fig. 7 is a diagram for determining pixels that are candidates for body hair in binarizing a skin image, and Fig. 8 is a diagram for determining pixels other than candidates for body hair in binarizing a skin image.

[0079] The counting unit 112 performs binarization processing on each of a plurality of pixels (e.g., all pixels) that make up the skin image. As shown in Fig. 6 , the counting unit 112 identifies a 21 x 21 block 221 that is centered around a processing target pixel 220 and has a vertical size of 21 pixels and a horizontal size of 21 pixels. Then, the counting unit 112 calculates a second average luminance, which is the average of the luminance values ​​of the 21 x 21 pixels included in the identified block 221.

[0080] The counting unit 112 calculates the threshold value Th by subtracting a constant c set for the block 210 including the target pixel 220 from the second average luminance of the 21 × 21 block 221 including the target pixel 220. The counting unit 112 then determines whether the luminance of the target pixel 220 is less than the threshold value Th. As shown in FIG. 7 , if the luminance of the target pixel 220 is less than the threshold value Th, the counting unit 112 determines that the target pixel 220 is a candidate pixel for body hair. As a result, the counting unit 112 sets a pixel value (e.g., 1) for the target pixel 220 indicating that the target pixel is a candidate pixel for body hair. Furthermore, as shown in FIG. 8 , if the luminance of the target pixel 220 is equal to or greater than the threshold value Th, the counting unit 112 determines that the target pixel 220 is not a candidate pixel for body hair. As a result, the counting unit 112 sets a pixel value (for example, 0) indicating that the pixel is not a candidate for body hair to the pixel 220 to be processed. In this way, the counting unit 112 binarizes the target region 207 of the skin image 200.

[0081] FIG. 9 is a graph showing the relationship between the second average luminance and the threshold value for determining pixels that are candidates for body hair.

[0082] 9, a threshold value Th is set according to the second average luminance, and pixels having pixel values ​​smaller than the threshold value Th are pixels that are candidates for body hair, while pixels having pixel values ​​equal to or greater than the threshold value Th are pixels that are not candidates for body hair. Pixels that are not candidates for body hair are considered to be pixels of areas other than body hair, such as skin, wrinkles, pores, and light moles.

[0083] The counting unit 112 performs binarization processing on the target region 207 of the skin image 200 to generate a binarized image 230 as shown in Fig. 10. Note that Fig. 10 is a diagram showing an example of a binarized image.

[0084] Next, the counting unit 112 detects pixel groups each made up of a plurality of adjacent pixels that are candidates for body hair from the binarized image 230. In other words, the counting unit 112 detects a group of pixels that are candidates for body hair as a pixel group.

[0085] 11 is a diagram for explaining an example of a method for detecting a group of pixels, in which a partial area 231 of a binarized image 230 is shown.

[0086] The counting unit 112 searches for a pixel with a pixel value of 1 among the multiple pixels constituting the binary image 230, for example, by raster scanning starting from the upper left pixel as indicated by the horizontal arrow in FIG. 11 . Then, when the counting unit 112 finds a pixel with a pixel value of 1, the counting unit 112 searches for a pixel with a pixel value of 1 counterclockwise, starting from the pixel to the lower left of the found pixel with a pixel value of 1 and targeting unsearched pixels. This search is repeated until the counting unit 112 returns to the pixel with a pixel value of 1 that was first found, thereby identifying pixels on the outline of the pixel group composed of pixels with a pixel value of 1. In this way, the counting unit 112 detects multiple pixel groups 241 composed of pixels with a pixel value of 1 in the binary image 230, as shown in FIG. 12 . The pixel groups 241 are indicated by black areas surrounded by circles 240 in FIG. 12 . FIG. 12 is a diagram showing an example of detection of pixel groups of pixels that are candidates for body hair in a binary image.

[0087] Next, for each of the detected pixel groups, the counting unit 112 sets a rectangle that surrounds the outline of the pixel group (i.e., the outline of the body hair) and has the smallest area. Fig. 13 is a diagram showing an example of a rectangle surrounding a pixel group. As shown in Fig. 13, the counting unit 112 may set a plurality of rectangles 242 and 243 that surround a pixel group 241, and set the rectangle 243 that has the smallest area among the plurality of rectangles 242 and 243 as the rectangle that surrounds the pixel group 241 and has the smallest area.

[0088] As explained using Figures 11 to 13, for each of the multiple body hairs in the skin image 200, the counting unit 112 (i) extracts the outline of the body hair, and (ii) sets a rectangle that surrounds the extracted outline and has the smallest area.

[0089] Next, the counting unit 112 determines the long side of the set rectangle 243 as the length of the hair, as shown in FIG. 14 . FIG. 14 is a diagram illustrating the process of determining the length of the hair. The length of the hair is indicated by the number of pixels corresponding to the long side. The counting unit 112 then counts, as the number of hairs, the number of rectangles, among the rectangles set in the pixel groups, whose determined hair length (i.e., the length of the long side of the rectangle) falls within a predetermined range. The predetermined range is, for example, a range indicated by the number of pixels greater than a threshold value Th1 and equal to or less than a threshold value Th2. The threshold value Th1 is a value smaller than the threshold value Th2 and corresponds to the number of pixels. For example, the threshold value Th1 may be 1, and the threshold value Th2 may be 100. The threshold values ​​Th1 and Th2 are example settings when, for example, the shooting distance is 20 cm and one pixel corresponds to 0.06 mm. That is, the threshold value Th1 is set to the number of pixels corresponding to 0.06 mm, and the threshold value Th2 is not limited to the above values ​​as long as it is set to the number of pixels corresponding to 6 mm.

[0090] [Details of Heat Map Data Generation Process] Next, the details of the heat map data generation process executed by the calculation unit 114 and the generation unit 115 will be described.

[0091] The counting result by the counting unit 112 may include the positions (two-dimensional positions) of one or more rectangles identified as body hair in the skin image 200. The calculation unit 114 uses the counting result by the counting unit 112 to count one or more rectangles identified as body hair that are included in each of a plurality of divided regions into which the skin region that is the region of the target part of the skin image is divided. In this way, the calculation unit 114 calculates the hair density for each of the plurality of divided regions. When the plurality of divided regions have the same area, the hair density may be the number of one or more rectangles identified as body hair that are included in one divided region. When the plurality of divided regions have different areas, the hair density may be a value obtained by dividing the number of one or more rectangles identified as body hair that are included in one divided region by the area of ​​the one divided region.

[0092] The generation unit 115 classifies the hair density calculated for each of the multiple divided regions calculated by the calculation unit 114 into multiple levels and represents the divided regions in a display mode indicating the classified level. For example, as shown in FIG. 15 , the generation unit 115 classifies the hair density into five display modes according to the hair density, and generates heat map data 300 in which the divided regions are represented in a display mode indicating the classified level. The display mode of multiple levels is not limited to five levels, and may be six or more levels. In FIG. 15 , a higher dot density (i.e., a darker color) indicates a higher hair density. The display mode may be set to vary depending on the dot density (color intensity). Furthermore, the display mode may be set to vary depending on the hue value. When different colors are set depending on the hue value, for example, the area with the highest hair density may be displayed in red, and the area with the lowest hair density may be displayed in blue.

[0093] Then, the output unit 116 outputs display information 400 for displaying the first heat map data 402 obtained from the first skin image and the second heat map data 401 obtained from the second skin image in a comparative manner, as shown in Figure 16.

[0094] [Operation] Next, an information processing method by the information processing device 100 will be described.

[0095] FIG. 17 is a diagram showing an example of a process for detecting the amount of hair by capturing a skin image at the second timing (for example, the first time).

[0096] The information processing device 100 activates the camera 107 and transitions to a photography preparation mode (S11).

[0097] The information processing device 100 determines whether the illuminance around the camera 107 is appropriate for capturing an image of the user's face based on the detection result detected by the image sensor of the camera 107 (S12).

[0098] If the information processing device 100 determines that the illuminance is appropriate (Yes in S12), the process proceeds to step S13, and if the information processing device 100 determines that the illuminance is not appropriate (No in S12), the process returns to step S11. Note that if the answer is No in step S12, the information processing device 100 may present a message urging the user to adjust the illuminance because the illuminance is not appropriate. The message may be displayed on the display 106, or may be output as audio from a speaker (not shown) provided in the information processing device 100. Furthermore, if the answer is No in step S12, the information processing device 100 may return to step S12.

[0099] The information processing device 100 determines whether the size of the user's face detected by the image sensor of the camera 107 is appropriate (S13).

[0100] If the information processing device 100 determines that the face size is appropriate (Yes in S13), the process proceeds to step S14, and if the information processing device 100 determines that the face size is not appropriate (No in S13), the process returns to step S11. If the information processing device 100 determines that the face size is not appropriate (No in S13), the information processing device 100 may present a message prompting the user to adjust the distance between the camera 107 of the information processing device 100 and the user's face. The message may be displayed on the display 106, or may be output as audio from a speaker (not shown) provided in the information processing device 100. If the information processing device 100 determines that the face size is not appropriate (No in S13), the process returns to step S13.

[0101] The information processing device 100 takes a plurality of consecutive shots (S14). For example, the information processing device 100 takes three consecutive shots. As a result, three skin images of the user's face are obtained.

[0102] The information processing device 100 performs a counting process on the skin image with the highest sharpness among the three skin images obtained in step S14 (S15). Details of the counting process will be described later with reference to FIG.

[0103] Next, the information processing device 100 determines whether or not to store the counting result of the counting process (S16). For example, the information processing device 100 may determine whether or not the counting result is within a predetermined range, and may store the counting result if it is within the predetermined range, or may not store the counting result if it is not within the predetermined range.

[0104] If the information processing device 100 determines that the counting results from the counting process are to be stored (Yes in S16), it proceeds to step S17, and if it determines that the counting results are not to be stored (No in S16), it returns to step S11.

[0105] The information processing device 100 stores the counting results of the counting process in the storage unit 117 (S17).

[0106] The information processing device 100 generates display information based on the counting results (S18). The display information includes, for example, the counting results. The display information may also include the heat map data described above.

[0107] The information processing device 100 outputs the display information (S19). Specifically, the information processing device 100 displays the display information on the display 106.

[0108] 18 is a flowchart showing the details of the counting process (S15). In step S15, steps S21 to S26 described below are executed.

[0109] The information processing device 100 sets a target region 207, in which body hair is to be detected, between the nose and upper lip on the user's face in the skin image 200 (S21).

[0110] Next, the counting unit 112 of the information processing device 100 binarizes the skin image 200 in order to detect body hair (S22), thereby obtaining a binarized image 230.

[0111] Next, the information processing device 100 searches for pixels having a pixel value of 1 among the plurality of pixels constituting the binary image 230, thereby identifying pixels on the contour of a pixel group made up of pixels having a pixel value of 1. In other words, the information processing device 100 identifies the contour of body hair based on the binary image 230 (S23).

[0112] Next, for each of the plurality of pixel groups detected based on the contours, the information processing device 100 sets a rectangle that surrounds the contour of the pixel group (i.e., the contour of the body hair) and has the smallest area (S24).

[0113] Next, the information processing device 100 specifies the long side of the set rectangle as the length of the body hair (S25).

[0114] Next, the information processing device 100 counts the number of rectangles, among the multiple rectangles, whose identified hair length (i.e., the length of the long side of the rectangle) is within a predetermined range, as the number of hairs (S26).

[0115] FIG. 19 is a diagram showing an example of a process for detecting the amount of hair by capturing a skin image at a first timing (for example, the second or later timing).

[0116] The information processing device 100 activates the camera 107 and transitions to a photography preparation mode (S21).

[0117] The information processing device 100 determines whether the illuminance around the camera 107 is appropriate for capturing an image of the user's face based on the detection result detected by the image sensor of the camera 107 (S32).

[0118] If the information processing device 100 determines that the illuminance is appropriate (Yes in S32), the process proceeds to step S33, and if the information processing device 100 determines that the illuminance is not appropriate (No in S32), the process returns to step S31. Note that if the answer is No in step S32, the information processing device 100 may present a message urging the user to adjust the illuminance because the illuminance is not appropriate. The message may be displayed on the display 106, or may be output as audio from a speaker (not shown) provided in the information processing device 100. Also, if the answer is No in step S32, the information processing device 100 may return to step S32.

[0119] The information processing device 100 determines whether the size of the user's face detected by the image sensor of the camera 107 is appropriate (S33).

[0120] If the information processing device 100 determines that the face size is appropriate (Yes in S33), the process proceeds to step S34, and if the information processing device 100 determines that the face size is not appropriate (No in S33), the process returns to step S31. If the answer is No in step S33, the information processing device 100 may present a message urging the user to adjust the distance between the camera 107 of the information processing device 100 and the user's face because the face size is not appropriate. The message may be displayed on the display 106, or may be output as audio from a speaker (not shown) provided in the information processing device 100. If the answer is No in step S33, the information processing device 100 may return to step S33.

[0121] The information processing device 100 continuously captures a plurality of images (S34). For example, the information processing device 100 continuously captures three images. As a result, three skin images of the user's face are obtained.

[0122] The information processing device 100 performs a counting process on the skin image with the highest sharpness among the three skin images obtained in step S34 (S35). The counting process is the same as the process in FIG.

[0123] The information processing device 100 compares a first counting result, which is the result of the counting process on the first skin image taken at the first timing, with a predicted hair volume value based on a second counting result, which is the result of the counting process on the second skin image taken at the second timing, and determines whether the absolute value of the difference between the first counting result and the predicted hair volume value is less than or equal to a predetermined threshold value (S36).

[0124] If the information processing device 100 determines that the absolute value is equal to or less than the predetermined threshold value (Yes in S36), the process proceeds to step S37, and if the information processing device 100 determines that the absolute value is greater than the predetermined threshold value (No in S36), the process returns to step S31. Note that if the result in step S36 is No, the information processing device 100 may present a message prompting the user to re-capture the skin image. The message may be displayed on the display 106, or may be output as audio from a speaker (not shown) provided in the information processing device 100.

[0125] The information processing device 100 calculates an evaluation value indicating the hair growth suppression effect based on the difference between the first counting result and the predicted hair volume value (S37). Note that the evaluation value may be calculated when the first counting result and the second counting result are compared in step S36.

[0126] The information processing device 100 stores the first count result obtained by the counting process (S38).

[0127] The information processing device 100 generates display information based on the first counting result and the second counting result (S39). The display information includes, for example, the first counting result and the second counting result. The display information may also include an evaluation value calculated based on the difference between the first counting result and the predicted hair volume value. As shown in FIG. 16 , the display information may be display information 400 including first heat map data 402 obtained from the first skin image and second heat map data 401 obtained from the second skin image, arranged so as to be comparable to the first heat map data 402.

[0128] The information processing device 100 outputs the generated display information (S40). Specifically, the information processing device 100 displays the display information on the display 106.

[0129] [Effects, etc.] Information processing device 100 according to the present embodiment is an information processing device 100 that evaluates the hair growth suppression effect of photoepilation device 10. Information processing device 100 includes acquisition unit 111, counting unit 112, and evaluation unit 113. Acquisition unit 111 acquires skin image 200 in which a target area of ​​a user (subject) is captured. Counting unit 112 counts the number of body hairs from skin image 200. Evaluation unit 113 evaluates the hair growth suppression effect based on a comparison result between a first counting result that is a counting result for a first skin image captured at a first timing and a predicted hair volume value at the first timing that is based on a second counting result that is a counting result for a second skin image captured at a second timing that is a first period before the first timing.

[0130] According to this, the first counting result for the first skin image at the first timing is compared with the predicted hair volume value predicted based on the hair growth suppression effect of the treatment by the photo-epilation device 10 at the timing corresponding to the second timing, so it is possible to determine whether the predicted hair growth suppression effect has been achieved, thereby enabling the hair growth suppression effect of the photo-epilation device 10 to be appropriately evaluated.

[0131] In the information processing device 100 according to the present embodiment, the first timing is a timing that is a second period after a treatment is performed by the photo-epilation device 10. The second timing is a timing that is a second period after a treatment is performed after a treatment by the photo-epilation device 10.

[0132] Therefore, both the first timing and the second timing can be set to a timing that is a second period after the corresponding treatment is performed, so that the hair growth suppression effect can be evaluated with reduced error due to the amount of body hair growth.

[0133] Furthermore, in the information processing device 100 according to this embodiment, when the first counting result is equal to or less than the predicted hair volume value, the evaluation unit 113 calculates an evaluation value indicating the hair growth suppression effect based on the difference between the first counting result and the predicted hair volume value, and outputs the calculated evaluation value.

[0134] According to this, if the first counting result is equal to or less than the predicted hair volume value, it can be determined that the photographing was successful and an appropriate first counting result has been obtained, and therefore an appropriate evaluation value can be calculated.

[0135] Furthermore, in the information processing device 100 according to the present embodiment, when the absolute value is greater than a predetermined threshold, the evaluation unit 113 outputs presentation information that prompts the user (subject person) to take a new skin image of the user.

[0136] According to this, if the absolute value is greater than a predetermined threshold, it can be determined that the image capture has failed, and an appropriate first counting result can be obtained by prompting the user to take the image again.

[0137] Furthermore, in information processing device 100 according to the present embodiment, counting unit 112 (i) extracts the outline of each of the plurality of body hairs in skin image 200, and (ii) sets a rectangle that surrounds the extracted outline and has the smallest area. Then, counting unit 112 counts, as the number of body hairs, the number of one or more rectangles of which the length of at least one of the long side and the short side falls within a predetermined range, among the plurality of set rectangles.

[0138] This makes it possible to exclude counting areas other than body hair, such as skin wrinkles, pores, and moles, and therefore to properly count body hair.

[0139] In addition, in the information processing device 100 according to this embodiment, the counting unit 112 sets a target area in the skin image 200 between the nose and upper lip of the user's (subject's) face where body hair is to be detected, and sets multiple rectangles within the target area.

[0140] Therefore, whiskers as body hair growing on a person's face can be counted appropriately.

[0141] Information processing device 100 according to the present embodiment further includes calculation unit 114, generation unit 115, and output unit 116. Calculation unit 114 divides a skin region, which is a region of a target part in skin image 200, into a plurality of divided regions and calculates a hair density for each of the plurality of divided regions. Generation unit 115 generates heat map data 300 of the hair density in the skin region based on the calculation results by calculation unit 114. Output unit 116 outputs display information 400 for displaying first heat map data 402 obtained from the first skin image and second heat map data 401 obtained from the second skin image in a manner that allows them to be compared.

[0142] This makes it possible to visualize the distribution of body hair density.

[0143] [Modifications] (1) In the above embodiment, information processing device 100 includes camera 107. However, this is not limiting, and information processing device 100 does not need to include camera 107 as long as it can acquire (receive) skin images from another information processing device via communication IF 104. For example, information processing device 100 may acquire skin images from a digital camera or an information terminal with a camera function, such as a smartphone or tablet terminal, or may acquire skin images from another information processing device in which skin images are stored. In this case, acquisition unit 111 is realized by communication IF 104.

[0144] (2) In the above embodiment, facial hair is used as an example of body hair in a target area, but the target area may be body hair in other areas. For example, the target area may be body hair growing on the armpits, chest, hands, pubic area, or legs.

[0145] (3) In the above embodiment, the evaluation unit 113 outputs the presentation information by displaying it on the output unit 116. However, the presenting information may be output by transmitting it to the user's mobile device. Upon receiving the presentation information, the mobile device may display the presentation information. This allows the user to visually recognize the presentation information displayed on the mobile device, and prompts the user to capture a skin image of the user using the information processing device 100.

[0146] [Others] In the above embodiments, each component may be configured with dedicated hardware, or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory. Here, the software that realizes the information processing device of the above embodiments is a program that causes a computer to execute each step included in the flowcharts shown in the figures.

[0147] The following cases are also included in this disclosure:

[0148] (1) Specifically, each of the above devices is a computer system consisting of a microprocessor, ROM, RAM, hard disk unit, display unit, keyboard, mouse, etc. A computer program is stored in the RAM or hard disk unit. Each device achieves its function when the microprocessor operates in accordance with the computer program. Here, a computer program is composed of a combination of multiple instruction codes that indicate commands to a computer to achieve a specified function.

[0149] (2) Some or all of the components constituting each of the above devices may be configured as a single system LSI (Large Scale Integration). A system LSI is an ultra-multifunctional LSI manufactured by integrating multiple components on a single chip, and specifically, is a computer system configured to include a microprocessor, ROM, RAM, etc. A computer program is stored in the RAM. The system LSI achieves its functions by the microprocessor operating in accordance with the computer program.

[0150] (3) Some or all of the components constituting each of the above devices may be configured as an IC card or a standalone module that can be attached to each device. The IC card or module may be a computer system configured with a microprocessor, ROM, RAM, etc. The IC card or module may include the above-mentioned ultra-multifunctional LSI. The IC card or module achieves its functions when the microprocessor operates in accordance with a computer program. The IC card or module may be tamper-resistant.

[0151] (4) The present disclosure may be embodied as the methods described above, a computer program that implements these methods on a computer, or a digital signal that includes the computer program.

[0152] The present disclosure may also be a computer program or a digital signal recorded on a computer-readable recording medium, such as a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD (Blu-ray (registered trademark) Disc), a semiconductor memory, etc. Alternatively, the present disclosure may be a digital signal recorded on such a recording medium.

[0153] Furthermore, the present disclosure may involve transmitting the computer program or the digital signal via a telecommunications line, a wireless or wired communication line, a network such as the Internet, data broadcasting, or the like.

[0154] The present disclosure may also be a computer system including a microprocessor and a memory, the memory storing the computer program, and the microprocessor operating in accordance with the computer program.

[0155] The program or the digital signal may also be implemented by another independent computer system by recording it on the recording medium and transferring it, or by transferring it via the network or the like.

[0156] (5) The above-described embodiments and modifications may be combined with each other.

[0157] The present disclosure is useful as an information processing device that can appropriately evaluate the hair growth suppression effect of a photoepilation device.

[0158] 10 Photo-hair removal device 100 Information processing device 101 Processor 102 Main memory 103 Storage 104 Communication IF 105 Input device 106 Display 107 Camera 111 Acquisition unit 112 Counting unit 113 Evaluation unit 114 Calculation unit 115 Generation unit 116 Output unit 117 Memory unit 200 Skin image 201-206 Feature points 207 Target area 208, 231 Area 210, 221 Block 220 Pixel to be processed 230 Binarized image 240 Circle 241 Pixel group 242, 243 Rectangle 300 Heat map data 400 Display information 401 Second heat map data 402 First heat map data A1 Area L1-L3 Straight line L4 Broken line Th, Th1, Th2: Threshold value c: Constant

Claims

1. An information processing device for evaluating the hair suppression effect of a light hair removal device, comprising: an acquisition unit for acquiring a skin image of a target area of ​​a subject; a counting unit for counting the number of body hairs from the skin image; and an evaluation unit for evaluating the hair suppression effect based on a comparison result between a first counting result which is the result of the counting for a first skin image taken at a first timing and a predicted hair volume value at the first timing based on a second counting result which is the result of the counting for a second skin image taken at a second timing that is a first period before the first timing.

2. The information processing device of claim 1, wherein the first timing is a timing a second period after a treatment is performed by the light hair removal device, and the second timing is a timing the second period after a treatment is performed following the treatment by the light hair removal device.

3. An information processing device as described in claim 1 or 2, wherein when the absolute value of the value obtained by subtracting the first counting result from the predicted hair volume value is equal to or less than a predetermined threshold value, the evaluation unit calculates an evaluation value indicating the hair growth inhibition effect based on the difference between the first counting result and the predicted hair volume value, and outputs the calculated evaluation value.

4. The information processing device according to claim 3, wherein the evaluation unit outputs presentation information prompting the subject to take a new skin image of the subject when the absolute value is greater than a predetermined threshold value.

5. An information processing device as claimed in any one of claims 1 to 3, wherein the counting unit: for each of a plurality of body hairs in the skin image: (i) extracts the contour of the body hair; (ii) sets a rectangle that surrounds the extracted contour and has the smallest area; and counts, among the plurality of set rectangles, the number of one or more rectangles whose length of at least one of the long sides and short sides is within a predetermined range as the number of body hairs.

6. The information processing device according to claim 5, wherein the counting unit sets a target area in the skin image between the nose and upper lip of the subject's face in which body hair is to be detected, and sets the multiple rectangles within the target area.

7. An information processing device as claimed in any one of claims 1 to 3, further comprising: a calculation unit that divides a skin region, which is the region of the target part in the skin image, into a plurality of divided regions and calculates a hair density for each of the plurality of divided regions; a generation unit that generates heat map data of the hair density in the skin region based on a calculation result by the calculation unit; and an output unit that outputs display information for displaying the first heat map data obtained from the first skin image and the second heat map data obtained from the second skin image in a state in which they can be compared.

8. An information processing method executed by an information processing device having one or more processors and evaluating the hair suppression effect of a light hair removal device, wherein the one or more processors: acquire a skin image of a target area of ​​a subject; count the number of body hairs from the skin image; and evaluate the hair suppression effect based on a comparison result between a first counting result which is the result of the counting for a first skin image taken at a first timing and a predicted hair volume value at the first timing which is based on a second counting result which is the result of the counting for a second skin image taken at a second timing which is a first period before the first timing.

9. A program for causing a computer to execute the information processing method according to claim 8.

Images