JP6062599B1 - Portable information device, dimension measuring method, and dimension measuring program - Google Patents

Abstract

The portable information device includes a camera, a tilt sensor, and a processing unit, and the processing unit superimposes a foot position guide image indicating a foot placement region, which is a region on which a foot is placed, on a camera video that is a video captured by the camera. Then, by using the tilt sensor, the tilt of the camera with respect to a predetermined plane is detected, and when the tilt of the camera is equal to or less than a predetermined tilt threshold, the foot placed in the foot placement area on the plane A still image including a reference object that represents a predetermined shape and size and is placed on the plane is captured by the camera to generate image data, and the reference object and the foot region in the image data are generated. Based on this, the dimensions of the foot are calculated.

Description

  The present invention relates to a technique for measuring dimensions with a portable information device.

  A technique for measuring the size of a foot from image data of a human foot has been proposed. Patent Document 1 discloses a foot placement base that is formed in a size that allows both feet to be placed in parallel, and has a substantially flat foot placement portion on which each foot is placed, and each foot of the foot placement base. A plurality of substantially plate-shaped mirrors that are tilted at a predetermined angle with respect to the placement site and are arranged on the side of the foot placement site, and spaced apart upward from the foot placement table. One or a plurality of imaging means for capturing the mirror image of the upper surface of both feet placed on the upper surface and the side surface of the foot reflected in the mirror, and outputting each image information of the upper and lower surfaces of both feet, and outputting from the imaging means There is disclosed a foot size measuring device provided with measurement processing means for computing the image information to be processed and deriving the dimensions of predetermined portions of both feet.

JP 2002-81912 A

  With the spread of Internet shopping, users can purchase footwear such as shoes from home without visiting a store. In order to purchase footwear that fits your foot, you need your foot dimensions or shoe size with some degree of accuracy. According to the device of Patent Document 1, the size of a foot can be measured. However, the device is a dedicated device that is premised on introduction into a store, and an individual user can measure the size of a foot at home or the like. Is a big one.

  The objective of this invention is providing the technique which measures a dimension using portable information devices, such as a smart phone and a tablet terminal.

  A portable information device according to an aspect of the present invention includes a camera, a tilt sensor, and a processing unit, and the processing unit captures a foot position guide image indicating a foot placement region, which is a region where a foot is placed, by the camera. The camera is superimposed on the camera image and the tilt sensor is used to detect the tilt of the camera with respect to a predetermined plane, and when the camera tilt is equal to or less than a predetermined tilt threshold, the foot placement on the plane A still image including a foot placed in an area and a reference object representing a predetermined shape and size and placed on the plane is photographed by the camera to generate image data, and the reference object in the image data A portable information device that calculates the size of the foot based on the foot region.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to measure a dimension using portable information devices, such as a smart phone and a tablet terminal.

It is a figure which shows a mode that the dimension of a leg | foot is measured with a portable information device. It is a block diagram of a portable information device. It is a flowchart of the whole process of foot measurement. It is a flowchart which shows the detailed process example which image | photographs a still image. It is a figure which shows an example of the image displayed on a touchscreen display at the time of imaging | photography. It is a figure which shows the example of a display of an inclination display image. It is a flowchart of the process which calculates the dimension of a leg | foot. It is a figure which shows a mode that planar correction is performed with respect to image data. It is a figure which shows a mode that the area | region of a leg | foot is correct | amended in three dimensions. It is a figure which shows a mode that a toe line is manually aligned. It is a figure which shows a mode that a toe line is aligned automatically.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a state in which the size of a foot is measured by a portable information device according to the present embodiment.

  The portable information device 10 according to the present embodiment is an information processing device that is used in a state of being held by a hand represented by a smartphone or a tablet terminal. The portable information device 10 can install an application software program and operates by executing the application. The portable information device 10 can realize various functions depending on the application to be installed.

  The portable information device 10 according to the present embodiment is installed with an application that makes it possible to measure the dimensions of the foot FT. Typically, the length of the foot FT is the length of the longest portion of the foot in the front-rear direction. Further, the width of the foot FT may be included as a dimension of the foot FT.

  For example, the size of the foot FT measured by this application can be used for shoe size selection when purchasing shoes on an EC site (electronic commerce site). In addition, the application itself may include not only a function of measuring the size of the foot FT but also various functions for using the EC site.

  When the size of the foot FT is measured by the portable information device 10, a still image is photographed so as to include the reference object CD having a predetermined shape and size and the foot FT. The size of the foot FT is calculated from the still image. The reference object CD is, for example, a card having a predetermined shape, size, and pattern.

  FIG. 2 is a block diagram of the portable information device. The portable information device 10 includes a processor 20, a storage device 12, a tilt sensor 13, a speaker 14, a touch panel display 15, a camera 16, and a communication module 17.

  The processor 20 is a processing device that executes an operating system and applications. The processor 20 realizes the functions of the guide unit 21, the tilt detection unit 22, the still image shooting unit 23, and the calculation unit 24 by executing the application. The functions of these units will be described later.

  The storage device 12 is a storage device that holds an application program, setting information necessary for the application to operate, data used for processing by the application, and the like.

  The tilt sensor 13 is a sensor that detects the tilt of the portable information device 10. The inclination of the portable information device 10 is also the inclination of the camera 16.

  The speaker 14 is an audio output device that outputs audio based on the processing of the processor 20.

  The touch panel display 15 is an operation display device in which an output device that displays an image, text, or the like on a screen based on processing of the processor 20 and an input device that receives a user operation are integrated. The output device displays an image or the like on the screen, and the input device accepts a touch device for the screen.

  The camera 16 outputs a real-time moving image and shoots a still image according to an instruction.

  The communication module 17 is a module that performs wireless communication via a mobile phone network or Wi-Fi. When purchasing shoes or the like at the EC site using the measured foot FT dimensions, the processor 20 accesses the EC site via the network using the communication module 17.

  In the portable information device 10 having the above-described configuration, the storage device 12 stores an application that makes it possible to measure the dimension of the foot FT, and the processor 20 executes the application in FIG. Perform the operation shown.

  FIG. 3 is a flowchart of the entire foot measurement process.

  First, the guide unit 21 displays a foot position guide image indicating a foot placement region, which is a region where the foot FT is placed, on the touch panel display 15 so as to be superimposed on a camera video that is a video captured by the camera 16 (step S101).

  The user adjusts the position of the foot FT and the position and direction of the camera 16 so that the foot FT fits in the foot placement area according to the guide based on the foot position guide image displayed on the touch panel display 15. At that time, adjustment is made so that a reference object representing a predetermined shape and size is also included in the camera image. The reference object is, for example, a predetermined card, and represents a predetermined shape and size by the card itself or a pattern displayed on the card.

  When the user adjusts the position or angle of the foot FT, the reference object, or the camera 16, the tilt detection unit 22 detects the tilt of the camera 16 with respect to a predetermined plane by using the tilt sensor 13. The predetermined plane is a floor as an example.

  When the still image capturing unit 23 tilts the camera 16 below the tilt threshold, the still image capturing unit 23 displays a still image including the foot FT placed in the foot placement region on the plane and the reference object placed on the plane. 16 is used to generate image data (step S102). The tilt threshold is a threshold related to the tilt of the camera 16, and is set in advance to a value that can obtain a desired accuracy as the dimension of the foot FT by correction based on the tilt with respect to image data captured by the camera 16.

  Since the reference object and the foot FT are stored in the generated image data, the calculation unit 24 extracts the area of the reference object and the foot FT in the image data, and based on the area of the reference object and the foot FT, The dimensions are calculated (step S103). For example, the length from the toe of the foot FT to the heel obtained from the shape and size of the region of the foot FT is calculated based on the shape and size indicated by the reference object. The processing of the calculation unit 24 includes the processing of the plane correction unit 25, the foot region detection unit 26, and the foot dimension calculation unit 27 as shown in FIG.

  In order to accurately calculate the size of the foot FT, the image data needs to have little distortion due to the tilt of the camera 16, but the mobile information device 10 such as a smartphone or a tablet terminal is fixed accurately and horizontally by hand. difficult. If the inclination of the camera 16 at the time of shooting is large, it is difficult to calculate the size of the foot FT with sufficient accuracy even if the image data is corrected. However, according to the configuration of the present embodiment, a still image is first shot in a state where the tilt of the camera 16 is within a range in which accuracy can be ensured by correction, and the obtained image data is corrected. It is possible to measure the dimension of the foot FT with few errors by the portable information device 10 that is held and operated.

  FIG. 4 is a flowchart illustrating an example of detailed processing for capturing a still image.

  First, while the guide unit 21 displays a guide image in which the foot position guide image is superimposed, the still image capturing unit 23 determines whether the tilt of the camera 16 is equal to or less than the tilt threshold based on the detection result of the tilt detection unit 22. It is determined whether or not (step S201).

  If the tilt of the camera 16 is larger than the tilt threshold, the still image capturing unit 23 displays on the touch panel display 15 that it is incapable of capturing (step S202), and returns to step S201. Note that when the user performs a shooting operation on the touch panel display 15 in a shooting disabled state, the still image shooting unit 23 generates a warning sound from the speaker 14 indicating that shooting is not possible. Good.

  If the tilt of the camera 16 is equal to or smaller than the tilt threshold in step S201, the still image capturing unit 23 displays on the touch panel display 15 that the camera is ready to be captured (step S203), and the user touches the touch panel display 15. It is determined whether there is a shooting operation (step S204).

  It should be noted that the shooting disabled state and the shooting enabled state may be displayed on the touch panel display 15 by the guide unit 21 or the tilt detection unit 22 in accordance with an instruction from the still image shooting unit 23.

  If there is no shooting operation by the user, the still image shooting unit 23 returns to step S201 and continues monitoring the tilt of the camera 16. If there is a photographing operation by the user, the still image photographing unit 23 photographs a still image with the camera 16 (step S205).

  FIG. 5 is a diagram illustrating an example of an image displayed on the touch panel display during shooting. Here, only the planar footprint shape is shown in the camera image for easy viewing, but in reality, the camera image shows legs in three dimensions as well as the feet.

  The guide unit 21 displays a foot position guide image 31 that positions the heel in the vicinity of the center in the front-rear direction in the camera image obtained by the camera 16. If the position of the camera 16 and the position of the heel are shifted in the front-rear direction, the size of the foot FT calculated from the image data is different from the size of the foot FT calculated from the image data due to the fact that the bulging part behind the heel has a height. An error may occur in a part. On the other hand, according to the present configuration, the camera 16 can be adjusted to the position of the heel in the front-rear direction by the guide based on the foot position guide image 31, so that the calculation error of the foot dimension due to the height of the heel can be suppressed. it can.

  The foot position guide image 31 includes a foot placement region 32, a vertical straight line 33, and horizontal straight lines 34a and 34b.

  The foot placement area 32 is on the front side of the entire area 30 photographed by the camera 16 and has a length that is substantially half of the entire area 30. By setting the front half of the entire area 30 photographed by the camera 16 to be the foot placement area 32, the heel can be positioned in the vicinity of the center of the entire area 30 in the front-rear direction. Since the center of the entire region 30 is substantially in front of the camera 16, it is possible to naturally position the eyelid in front of the camera 16.

  The guide unit 21 displays the foot position guide image 31 on the right front side of the entire area 30 when shooting the right foot, and displays the foot position guide image 31 on the left front side of the entire area 30 when shooting the left foot. . For example, when shooting the right foot, the reference object CD can be placed on the left side of the right foot so that both the right foot and the reference object CD can be stored in the image data in a natural shooting posture, and the position of the camera 16 in the front-rear direction is taken into account. Can be matched.

  The foot position guide image 31 includes a first straight line (longitudinal straight line 33) that matches the longest part of the foot FT, and two first movable lines that intersect the first straight line and are movable in the extending direction of the first straight line 33. 2 straight lines (lateral straight lines 34a and 34b). Then, the calculation unit 24 calculates the size of the foot based on the distance between the intersections of the two second straight lines 34 a and 34 b and the first straight line 33. By aligning the longest part of the foot FT with the first straight line 33 and aligning the second straight lines 34a, 34b with the front and rear ends (toe and heel) of the foot FT, It is possible to calculate the dimensions.

  The tilt detection unit 22 displays a tilt display image 35 on the touch panel display 15 that visually represents the tilt of the camera 16 detected by the tilt sensor 13 in real time. According to this, since the user can visually confirm the tilt of the camera 16 with the tilt display image 35, the angle of the camera 16 at the time of shooting can be determined.

It can be easily adjusted below the inclination threshold.

  FIG. 6 is a diagram illustrating a display example of the tilt display image. When the tilt of the camera 16 exceeds the tilt threshold, the tilt detector 22 indicates that the still image cannot be captured in the tilt display image 35 and does not allow the camera 16 to capture a still image. In the correction based on the shape of the reference object CD, a desired accuracy can be obtained as long as the tilt of the camera 16 is below a certain level. In the configuration of the present embodiment, it is ensured that the tilt of the camera 16 is equal to or less than a predetermined tilt threshold when capturing a still image, so that the image data of the captured still image is corrected based on the shape of the reference object CD. The desired accuracy can be obtained with certainty.

  6A, 6B, and 6C show an inclination display image 35 simulating a round bubble level. The inclination of the portable information device 10 or the camera 16 is represented by the position of a bubble image 35a that simulates a bubble. If the bubble image 35a is positioned near the center of the tilt display image 35, it indicates that the portable information device 10 or the camera 16 is horizontal. In the state of FIG. 6A, the bubble image 35 a is greatly deviated from the center of the tilt display image 35. At this time, it is assumed that the tilt of the camera 16 is larger than the tilt threshold, and still image shooting is prohibited. For this reason, the display of the tilt display image 35 indicates that photographing is not possible. In the example of FIG. 6A, the tilt display image 35 is hatched.

  In the example of FIG. 6B, the bubble image 35 a is displayed near the center of the tilt display image 35. In the example of FIG. 6C, the bubble image 35a is displayed at the center of the tilt display image 35. In the states of FIGS. 6B and 6C, it is assumed that the tilt of the camera 16 is equal to or smaller than the tilt threshold and still image shooting is permitted. For this reason, the tilt display image 35 indicates that the photographing is possible. In the examples of FIGS. 6B and 6C, the tilt display image 35 is not hatched, unlike the example of FIG.

  FIG. 7 is a flowchart of a process for calculating a foot dimension. Here, looking back at FIG. 2, the calculation unit 24 includes a plane correction unit 25, a foot region detection unit 26, and a foot dimension calculation unit 27.

  Referring to FIG. 7, the plane correction unit 25 corrects distortion due to the tilt of the camera in the image data based on the shape of the reference object CD in the image data (step S301). Subsequently, the foot area detection unit 26 detects the area of the foot FT in the image data after the plane correction by the plane correction unit 25 (step S302). The region of the foot FT can be specified based on the pixel value of each pixel in the image data. Next, the foot dimension calculation unit 27 calculates the dimension of the foot based on the relative size of the foot FT region detected by the foot region detection unit 26 with respect to the reference object CD in the image data. In this way, first, distortion due to the tilt of the camera 16 in the image data is corrected, and based on the relative relationship between the area of the foot FT in the corrected image data and the size of the reference object CD whose size is known, Since the dimension of the foot FT is calculated, a highly accurate dimension can be obtained.

  FIG. 8 is a diagram illustrating a state in which the planar correction is performed on the image data. 8A and 8B show still images before and after correction. In the still image, the reference object CD and the foot FT disposed in the foot placement region 32 are accommodated.

  FIG. 8A shows a still image before correction, which is taken by the tilted camera 16. Here, the tilt of the camera 16 is naturally equal to or less than the tilt threshold. The plane correction unit 25 recognizes the original shape and size of the reference object CD, and corrects the still image data so that the reference object CD in the still image has the original shape. At this time, the plane correction unit 25 may use, for example, an existing trapezoidal distortion correction technique. FIG. 8B shows a still image after correction. In the corrected still image, the distortion of the reference object CD is eliminated, and accordingly, the distortion of the foot FT area is also eliminated.

  When the foot FT region is specified from the corrected still image data, the foot region detection unit 26 divides the foot placement region into a plurality of regions based on the pixel value of each pixel, and the center portion of the foot placement region 32 The area of the foot FT may be a region formed by pixels having a difference from the pixel value in the central portion of the pixel value equal to or less than a predetermined value. In FIG. 8, since the footprint shape is shown as the foot FT for easy viewing, the toes are separated from the feet, but actually, the portion of the feet including the toes becomes a continuous region. Further, there are cases where the nail portion of the foot FT has a pixel value different from other portions due to an artificial nail or pedicure. Considering this, the nail portion may be specified by the pattern of the foot shape, and the specified portion may be included in the region of the foot FT even if the pixel value is different.

  FIG. 9 is a diagram illustrating how the foot region is corrected three-dimensionally.

  The foot size calculation unit 27 calculates the foot FT based on the reference object CD, the region of the foot FT, the angle θ with respect to the floor surface 43 of the straight line 42 connecting the camera 16 and the toe FTA, and the height H1 of the toe FTa. The dimension L2 is calculated. By aligning the camera 16 with the position of the 踵 FTb and making the straight line 41 connecting the camera 16 and the 踵 FTb perpendicular to the floor surface 43, it is possible to reduce the error on the heel side where a relatively large error is likely to occur. Further, since a relatively small error on the toe side caused by the positional deviation between the camera 16 and the toe FTa can be reduced by considering the height H1 of the toe FTa, an error in the dimension L2 of the foot FT as a whole. Can be kept small.

At this time, the foot dimension calculation unit 27 corrects the apparent dimension L1 of the area of the foot FT detected by the foot area detection unit 26 to the actual dimension L2 of the foot FT using Expression (1).
L2 = L1-H1 / tan θ (1)

  Here, the height H1 of the toe FTa may be a fixed value or a value proportional to the dimension L1. When the height H1 is a fixed value, for example, it may be about 1.5 cm. The angle θ can be easily calculated from the position of the pixel where the toe FTa is located.

  Next, the alignment of the second straight line (lateral straight line, toe line) 34a on the toe side in the foot position guide image 31 will be described.

  The guide unit 21 can be manually moved along the second straight line 34a by a user operation. The user can move the second straight line 34a by dragging on the touch panel display 15, for example. The guide unit 21 is a position where the change of the pixel value in the predetermined region including the part of the first straight line 33 and the toe FTa is equal to or greater than a predetermined pixel value change threshold. In addition, it is possible to automatically move to a position closest to the current second straight line 34a.

  In order to accurately calculate the size of the foot FT, it is necessary to accurately align the second straight lines 34a and 34b with the front and rear ends (toe FTa and heel FTb) of the foot FT. High-precision alignment is possible by automatically detecting the position where the pixel value changes in the image data by a predetermined value or more as the end of the foot FT and automatically aligning the second straight lines 34a and 34b to the position. It is. On the other hand, due to the influence of a pedicure or an artificial nail, there is a possibility that the position of the toe FTa may be wrong in the determination based on the pixel value. On the other hand, in the present embodiment, after the second straight line 34a is roughly aligned manually, the position of the second straight line 34a can be accurately adjusted based on the change in the pixel value of the image data. . As a result, it is possible to achieve both high-accuracy alignment and reduction of toe misjudgment.

  FIG. 10 is a diagram illustrating a state in which the toe line is manually aligned. First, the user aligns the second straight line (toe line) 34a with the toe FTa by dragging while watching the camera image on the touch panel display 15. Since the user aligns the second straight line 34a while visually observing, the toe FTa is not erroneously determined even if there is an artificial nail or pedicure. However, since it is a drag operation to the touch panel display 15, it is difficult to accurately align the second straight line 34a with the tip of the toe FTa.

  Therefore, the following steps are prepared. In the determination of the next step, a limited area 32a including the toe FTa portion of the camera image is used.

  FIG. 11 is a diagram illustrating a state in which the toe lines are automatically aligned. As shown in FIG. 11, the guide unit 21 automatically moves to a position where the change in the pixel value is equal to or greater than a predetermined pixel value change threshold in the region 32a and closest to the current second straight line 34a. Let As a result, it is possible to eliminate an error generated when the second straight line 34a is manually moved in the previous step.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to this example.

  In the present embodiment, both of the two second straight lines 34a and 34b are movable, but either one may be fixed and only the other may be movable. For example, the second straight line 34b on the heel side may be fixed to the foot placement region 32 and only the second straight line 34a on the toe side may be moved. This makes it possible to more accurately match the position of the heel FTb and the position of the camera 16 in the front-rear direction.

  Moreover, although the example which measures the dimension of foot FT was shown in this embodiment, the dimension of the other site | part of a human body can be measured by the process similar to this embodiment as another example. When measuring the dimensions of the hand, the end on the wrist side is made to correspond to the heel FTb in this embodiment, and the end of the fingertip is made to correspond to the toe FTa in this embodiment. The camera 16 is aligned with the wrist end, and three-dimensional correction is performed on the fingertip side.

  The guide unit 21 superimposes a hand position guide image indicating a hand placement area, which is an area where the hand is placed, on a camera video that is a video captured by the camera 16. The inclination detection unit 22 detects the inclination of the camera 16 with respect to a predetermined plane, for example, a table surface, by using the inclination sensor 13. When the tilt of the camera 16 is equal to or less than the tilt threshold, the still image capturing unit 23 causes the camera 16 to display a still image including the hand placed in the order value area on the predetermined plane and the reference object CD placed on the plane. Shoot and generate image data. The calculation unit 24 calculates the size of the hand based on the reference object CD and the hand region in the image data. The dimension of the hand is a dimension of a part or all of a part such as the length of the entire hand, the length of the finger, and the thickness of the finger.

  Moreover, although the example which measures the dimension of the site | part of a human body called a leg was shown in this embodiment, this invention is not limited to this example.

  As another example, the dimensions of an article placed on a floor surface or a table surface can be measured. For example, the size of a shoe can be measured by the portable information device 10.

  Since the shoe has a shape and size approximately similar to those of the foot, it is possible to measure the size by the same processing as in this embodiment. The guide unit 21 superimposes a shoe position guide image indicating a shoe placement area, which is an area for placing shoes, on a camera image that is an image captured by the camera 16. The tilt detection unit 22 uses the tilt sensor 13 to detect the camera 16 with respect to a predetermined plane such as a floor surface or a table surface. When the tilt of the camera 16 is equal to or less than a predetermined tilt threshold, the still image capturing unit 23 displays a still image including shoes placed in the shoe placement area on the plane and the reference object CD placed on the plane. 16 is used to generate image data. The calculation unit 24 calculates the shoe size based on the reference object CD and the shoe region in the image data.

  As another example, the size of the clothes can be measured by the portable information device 10. In this case, the guide unit 21 superimposes a clothes position guide image indicating a clothes arrangement area, which is an area where clothes are placed, on a camera image that is an image captured by the camera 16. The inclination detection unit 22 detects the inclination of the camera 16 with respect to a predetermined plane such as a floor surface or a table surface by using the inclination sensor 13. When the tilt of the camera 16 is equal to or less than a predetermined tilt threshold, the still image capturing unit 23 displays a still image including clothes placed in the clothes placement area on the plane and the reference object CD placed on the plane. 16 is used to generate image data. The calculation unit 24 calculates the size of the shoe based on the reference object CD and the clothing region in the image data. In the case of general clothes, the height that needs to be taken into consideration for the foot or the like can be ignored, so that the three-dimensional correction by the foot dimension calculation unit 27 does not have to be performed as described above.

  The above-described embodiments of the present invention are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to those embodiments. Those skilled in the art can implement the present invention in various other modes without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Portable information apparatus, 12 ... Memory | storage device, 13 ... Sensor, 14 ... Speaker, 15 ... Touch panel display, 16 ... Camera, 17 ... Communication module, 20 ... Processor, 21 ... Guide part, 22 ... Detection part, 23 ... Stationary Image capturing unit, 24 ... calculation unit, 25 ... planar correction unit, 26 ... foot region detection unit, 27 ... foot size calculation unit, 30 ... entire region, 31 ... foot position guide image, 32 ... foot placement region, 32a ... region 33 ... Vertical straight line (first straight line) 34a ... Horizontal straight line (second straight line, toe line) 34b ... Horizontal straight line (second straight line) 35 ... Tilt display image 35a ... Bubble image 41 ... straight line, 42 ... straight line, 43 ... floor surface

Claims (13)

A camera, a tilt sensor, and a processing unit;
The processor is
A foot position guide image indicating a foot placement area that is a foot placement area is superimposed on a camera video that is a video captured by the camera,
By detecting the tilt of the camera with respect to a predetermined plane by using the tilt sensor,
When the camera tilt is equal to or smaller than a predetermined tilt threshold, a still image including a foot placed on the foot placement area on the plane and a reference object representing a predetermined shape and size and placed on the plane. Shooting with the camera to generate image data,
Calculating the dimensions of the foot based on the reference and the foot region in the image data;
Portable information device.   The portable information device according to claim 1, wherein the processing unit displays the foot position guide image for positioning a heel near the center in the front-rear direction in the camera image.   The portable information device according to claim 2, wherein the foot placement area is on a front side of an entire area photographed by the camera and has a length approximately half of the entire area.   The processing unit displays the foot position guide image on the right front side of the whole area when photographing the right foot, and displays the foot position guide image on the left front side of the whole area when photographing the left foot. Item 4. The portable information device according to Item 3. The foot position guide image includes: a first straight line that matches the longest part of the foot; and two second straight lines that intersect the first straight line and are movable in a direction in which the first straight line extends. Including
The processing unit calculates the size of the foot based on a distance between intersections of the two second lines with the first line.
The portable information device according to claim 1.   The second straight line can be manually moved by a user operation, and can be automatically moved to a position closest to the second straight line where a change in pixel value is equal to or greater than a predetermined pixel value change threshold. Item 6. The portable information device according to Item 5. The processing unit displays a tilt display image that visually represents the tilt of the camera detected by the tilt sensor.
The portable information device according to claim 1.   The processing unit indicates that when the tilt of the camera exceeds the tilt threshold, it indicates that the tilt display image is incapable of shooting, and does not allow shooting of a still image by the camera. The portable information device described in 1. The processor is
Correcting distortion due to the tilt of the camera in the image data based on the shape of the reference object in the image data;
Detecting the area of the foot in the image data after correction;
Calculating the size of the foot based on the relative size of the detected foot region relative to the reference in the image data;
The portable information device according to claim 1.   The processing unit calculates the size of the foot based on the reference object, the foot region, an angle of a straight line connecting the camera and the toe to the plane, and a height of the toe. 9. The portable information device according to 9. The processor is
A guide unit that superimposes a foot position guide image indicating a foot placement area, which is a foot placement area, on a camera image that is an image captured by the camera;
An inclination detector that detects the inclination of the camera with respect to a predetermined plane by using the inclination sensor;
When the tilt of the camera is equal to or less than the tilt threshold, a still image including a foot placed in the foot placement area on the plane and a reference object representing a predetermined shape and size and placed on the plane A still image shooting unit for generating image data by shooting with a camera;
A plane correction unit that corrects distortion due to tilt of the camera in the image data based on the shape of the reference object in the image data;
A foot region detector for detecting the foot region in the image data after correction;
A foot size calculation unit that calculates the size of the foot based on the size of the detected foot region and the size of the reference object in the image data;
The portable information device according to claim 1, comprising: A dimension measurement method using a portable information device including a camera and a tilt sensor
The guide means superimposes a foot position guide image indicating a foot placement area, which is an area where the foot is placed, on a camera video that is a video captured by the camera,
The tilt detection means detects the tilt of the camera with respect to a predetermined plane by using the tilt sensor,
When the still image photographing means has a tilt of the camera equal to or less than a predetermined tilt threshold, the foot placed in the foot placement area on the plane and a reference object placed on the plane representing a predetermined shape and size A still image including the above is taken by the camera to generate image data,
The calculation means calculates the size of the foot based on the reference object and the foot region in the image data.
Dimension measurement method. A dimension measurement program executed by a portable information device having a camera and a tilt sensor,
A procedure for superimposing a foot position guide image indicating a foot placement area, which is a foot placement area, on a camera video that is a video captured by the camera;
Detecting the tilt of the camera relative to a predetermined plane by using the tilt sensor;
When the camera tilt is equal to or smaller than a predetermined tilt threshold, a still image including a foot placed on the foot placement area on the plane and a reference object representing a predetermined shape and size and placed on the plane. A procedure for generating image data by photographing with the camera;
A dimension measurement program for causing a computer to execute a procedure for calculating the dimension of the foot based on the reference object and the foot region in the image data.