JPS58161806A - Finger length measuring device - Google Patents

Abstract

PURPOSE:To perform the measurement of the finger length of a human hand simply and accurately, by obtaining the maximum and minimum points of the contour of the hand from a raster image obtained by using an image pickup device. CONSTITUTION:Luminous flux 100 from a light source 14 is made to be a parallel light beam through a Fresnel lens 16 and irradiated on the hand 10 mounted on a measuring table 12 comprising reinforced glass. The passed light is inputted in a video camera 18, while the camera 18 is rotated by specified times through a rotary device. The raster images having different rotary angles are sent to an image analyzing device 20 and the maximum and minimum points of the contours of the fingers of the hand are obtained. Based on the difference, the length of each finger can be measured simply and accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a finger length measuring device, and more particularly to a finger length measuring device for measuring the length of fingers of a hand.

The fingers of each person's hands have different lengths; in general, the combination of the lengths of the four fingers excluding the thumb makes it easy to distinguish between the person himself and another person. An h-length measuring device is used that measures the lengths of a plurality of fingers on one hand and compares them with registered values to identify an individual.

FIG. 1 shows an example of finger length definition used in such finger length measurement. In the figure, when the hand is fixed with the palm 10 slightly open, the central axis of the index finger (viewed in two dimensions) xl and the central axis of the ring finger X! The intersection of θ
Then, from θ to the tops of the index finger, middle finger, ring finger, and little finger f,
f,, f,・Length up to f4 IIg 11 @ l
Define as @e/4. Further, the length from - to the bottom W1 of the web between the index finger and the middle finger is defined as 1, and the length from the end to the bottom W of the web between the ring finger and little finger is defined as 10.

In this ζ, the length of the index finger is l'1, the length of the middle finger is l'h, the length of the ring finger is //, and the length of the little finger is //, then the length of the first finger is (1). Z', = /, -Z can be expressed by the formula.

Devices for measuring finger length in this way have been conventionally used in Japanese Patent Application Laid-open Nos. 11556-1982 and
t42s) proposals have been made.

The proposal of JP-A No. 53-11556 is to provide nine slits along the famous finger of the hand to be measured, to press the fingers of the hand to be measured along these slits, and to mechanically attach the top of the finger opposite to the slit. The content is to find the length from to the web.

Previously, the proposal in Japanese Patent Application Laid-Open (BL-1428, BII-1429) is to attach a sensor such as a line sensor along a slit, press the finger of the hand to be measured along the slit, and use the sensor to generate electricity. The purpose of this test is to find the length from the top of the finger to the web.

All of these conventional finger length measuring devices exhibit excellent effects in that they can accurately measure finger lengths and allow individual identification to be performed well.

However, in the ninth step, it was necessary to place the palm of the hand accurately along the provided slit, which had the disadvantage that the measurer required a considerable amount of experience.

i9. In conventional finger length measuring devices, the slit used for finger length measurement is formed to match the general shape of a hand. However, the shape of the handprint of the measurer is essentially infinitely different. The only people who can accurately measure this rounding and finger length are those who have a hand that fits this slit shape.
If the hand shape does not match the slit shape, the palm of the hand cannot be accurately placed along the slit, and the finger length cannot be accurately measured.

In addition, in the proposal of Unexamined Japanese Patent Application (BL-1428, BL-t42s), it is necessary to attach a sensor such as a line sensor according to the Surin) 0 shape, and the accuracy of sensor attachment is important for the reproducibility of measured values. The problem was that it had a major impact on the industry and was difficult to construct.

The present invention has been made in view of such conventional problems, and its purpose is to provide a finger length adjustment device that can easily and accurately measure the finger length of a measurer's hand. .

To achieve this objective, the device of the present invention includes a photographing device that is placed opposite the palm of the hand to be measured and converts the previous colleague into an electrical Rusk image by Rusk scanning, and Obtain multiple rask images rotated at different rotation angles, and calculate the maximum and minimum positions of the contours of the fingers of the hand for each of the obtained 2-star images to determine the finger length of the famous finger. and an image analysis device for calculating, and the maximum finger length of the famous finger calculated by the image analysis device is set as the final measured value of the finger length of the famous finger.

Next, a preferred embodiment of the present invention will be described with reference to FIG. 1iK.

FIG. 1 shows a preferred embodiment of the finger length measuring device of the present invention, in which the palm of the hand whose finger length is to be measured is placed on a measuring table 12 made of transparent tempered glass. .

A light source 14 is disposed above the measuring table 12, and a light beam 100 from the light source 14 is irradiated onto the measuring table 12 as a parallel beam by a 7-Renel lens 16.

Further, a video camera 18 is disposed below the measuring table 12 as a video recording device. This video camera 18 is installed at a position where the light emitted from the light source 14 is transmitted through the measurement table 12, and the palm 1G placed on the measurement table 12 is connected to the imaging surface. It is conditioned to be great.

Then, the video camera 18 converts the optical image into an electrical raster image by raster scanning and outputs it.

A characteristic feature of the present invention is that the raster image obtained in this manner is analyzed to determine the finger length of the famous finger.

In the present invention, this rounding process involves obtaining a plurality of raster images that are rotated around a predetermined image position and having different rounding angles. An image analysis device 20 is provided which calculates the finger length of the famous finger by finding the minimum position.

In this embodiment, a rotation device 22 for the camera 18 is provided in order to obtain a plurality of raster images rotated at different rotation angles around a predetermined image position. 11m is rotated a predetermined number of times around its optical central axis.

FIG. 3 shows a detailed circuit block of the image analysis device 20 shown in FIG. 2. In FIG.

First, the video signal output from the video camera 18 is 2
The signal is input to the value conversion circuit 30. This binarization circuit 30 binarizes the input video signal with a predetermined threshold value, converts the height of the hand to 111, and the space outside the hand to @01, which are input to the line pack 732.

The line buffer 32 stores and holds a plurality of lines of input video signals converted into binary digital values, and transfers them all at once to screen memories 34 and 36 at a predetermined timing.

The screen memories 34 and 36 are formed by a memory group two-dimensionally arranged corresponding to l raster scans of the video camera 18, and store video signals transferred from the line buffer 32 for l raster scans.

38 is the raster scan timing of the video camera 18;
A synchronous write control unit that controls the data acquisition destination and timing to the line buffer 32, and the line buffer 3
The transfer timing of the data No. 2 to the screen memory 34.36 and the write address of the same screen memory 34.36 are also controlled.

40 is a microprocessor (hereinafter simply referred to as CPU), and 42 is a control memory that executes a signal processing algorithm to be described later. This control memory 42 consists of a ROM that stores a program for realizing the algorithm, and a temporary storage RAM for its execution. Then, the synchronous write control unit 38 starts the same control in response to a command from the 0PU 40, and when the binary image for one raster scan is completed in the screen memory 34 or 36, a message is written to notify that. The destination issues a loading completion signal to 0P040. The contents of the previously written screen memory 34.3@ can be read out from 0P040 at any time.

Screen memory 34.36 is prepared for 2 screens because
The purpose is to write data alternately by the synchronous write control unit 38 and read data by the 1c OPU 40 alternately at l raster scan intervals. Therefore, the 0PU 40 can read and process the free Kl screen memory during l raster scans without being interfered with by write control operations.

Reference numeral 44 designates an input/output interface 7 which inputs and outputs a start signal and a termination signal to the video camera rotation mechanism 22, and inputs and outputs control signals and data to and from an external device (not shown).

The present invention has the above configuration, and its operation will be explained in detail next.

When the measurer places his/her hand on the measuring table 12, a signal from a touch sensor (not shown) is transmitted to the (!PU40) and the following series of operations is started.The processing of the cptr40 is stored in the ROM of the control memory 42. This is accomplished by the 0PtT 40 sequentially executing the written control program, and it goes without saying that during this execution, the RAM of the control memory 42 is used as a temporary storage memory for data processing.

0PU40 activates the synchronous write control unit 38, and
The 1-turn mechanism 22 is activated via the input/output interface 44 and waits for a 1iiifti write completion signal from the synchronous write control unit 38.

The synchronous write control unit (hereinafter abbreviated as control unit) SS is 0PU4
Upon receiving the activation signal from 0yosho, it issues a synchronization signal for the rusk scan to video camera 1$. The video signal from the video camera 18 is converted into a pixel-corresponding binary signal (1oro) in the binarization circuit section 30 and written into the line batts 732 by the control clock of the control section 380. Upon completion of scanning l lines (after l horizontal scanning), the control unit 38 transfers the contents of the buffer to a predetermined area of the screen memory 34.

Repeat this and when 1 raster scan is completed, 2 of 1 screen
Complete the screen memo IJ 34K. Control unit 38
outputs a write completion signal to 0Pt) 40, and continues,
In response to the next rask scan, the above writing operation is performed in the screen memory 36 this time. The CPU 49 reads out the contents of the screen memory 34 while the control unit 38 is writing to the screen memory 36, and as described above, the CPU 49 reads out the contents of the screen memory 34, and as described above, the CPU 49 reads out the contents of the screen memory 34.
The configuration of the screen memory 34.36 in which the digitization data is stored is shown, and the screen memory 34.3 of the embodiment corresponds to the pixels of the imaging surface of the video camera 18 and has logical Km+1 rows and n+
It is a two-dimensional layout memory with one column, and the intersection of each row and column is a 1-bit memory element.

Also, each row corresponds to the horizontal scanning axis in the rask scan. The values of m and n are determined by the degree of resolution of the camera, the required measurement accuracy, and the power, for example, n = m = 255.511
．． It takes a value such as 1023.

In the screen memory shown in FIG. 4, the hatched area indicates the range of logic III corresponding to the transmission of the palm of the hand*, and the area outside the hatched area indicates the range of logic IO1 corresponding to the space outside the hand. By reading this memory, 0PU40 stores the memory locations Pi, , P at the top of each of the four fingers.
L, , Pi, , PL4 and web part Pi, ,
Determine Pi, . This is equivalent to finding the maximum and minimum points of the boundary curve S of Ilo when the rows and columns of this memory are regarded as orthogonal coordinates (J:, 7). However, the suffix 1 indicates the relative number of the screen, and from the start of measurement, the screen correspondence 1, 2, . -3・・・・・・・・・・・・
・It is distinguished from

One method for determining the maximum and minimum points will be explained based on the following KfgS diagram and FIG. 6. Incidentally, FIGS. 5 and 6 show the stored contents of each column of the screen memo 1734.3@.

The 0PU 40 checks the contents of the screen memory for each scanning line from the upper left corner. First is the space part, so part 1
The contents of the line are all O, which is shown in Figure 2 (IL) K.

As you move down the reading line one by one, a black area corresponding to part of the finger finally appears. This is shown in Figure 5(b)K. Also, let this memory location be P (x',, y'1) and the control RAM
K remember. If Kurobe's l run length is 1 or more, it is defined as l II left side. At this time, "l" and "y/" are the number of columns from the left side of the location -1 and the number of rows from the top -1, respectively.

The next reading sequence is shown in Figure 5(e). At this time, the front row (Figure 5 (
The connection condition for Kurobe with b)) is determined by examining the AND conditions corresponding to the run length RL Otori and the number of columns X in (0) in the same figure, and the MND condition is satisfied in either of them.From K, RL is p (! /,
, ylm).

As the reading line is further lowered, a new black area that is not connected appears as shown in Figure 5 (1) K. ,y/,
) is stored in the control RAMK. When Kurobe's run length is 1 or more, the address on the leftmost side is P(X'
,,y′ri.

The next read line is shown in (e)K of the same figure. In this case, the connection condition of the black part with the previous line is (-) run length RL,, RL, and (
In this example, P("%, y') is determined by RL,
It is determined that the RL in (d) is connected to the RL in (.).

Further down the reading line, as shown in (f), the run lengths RLz (P("t, 7's) K-connected), RL, (P(x', , 7-) K-connected) ] K is not connected to the new nine Kurobe l readings, and the left side of these run lengths is p (x/, 1./,
).

Also, as the reading line is further lowered, the run length RLI (p(z'+, 7't)KW continuation) is shown in (g).
, RL, (connected to P(X', , 7', ))], R
A new black part that is not connected to L, (connected to P(x',, Y',)) can be read. This is called P("4 s yl4)
shall be.

As the reading line is further lowered, the run lengths RL and %RL4 shown in FIG. At this time, the corresponding part on the left side of the white run length between RL and RL in the previous row (h) is stored in the control RAMK as p (xl,, y-).

When the reading line is further lowered, each run length xRL shown in (j)
4 [Connected to P (x', , y'4)], RL, , [
P(X's, F's)K connection], RLs[P(
”s s 7's )] is connected to (k
)K, the RL□ and RL are combined to form a run length of %1. At this time, RL, 1, R of the previous row (j)
The body part of the white run length between Ls is “P(!-1y′
, ) and the combined run length is RLttm.

When reading the lower row further, the run length shown in (1) is R”4, and RLIlm is the result of the next lower row reading (1 m).
As shown in K, they are combined. At this time, RL4 and R in the front row (Z)
The corresponding part on the left side of the white run length between Iltts is p
(11,, yl, ) and complete the downward reading.

Based on the above results, Pij (j=1 to 6
) is determined as follows based on the shape of the finger.

Of course, the reason why the suffixes of the left term and the crest do not match in [1[, is that the suffix of the left term is fixed at the minutiae of the hand, whereas the suffix of the left term is fixed at the minutiae of the hand, whereas the suffix of the crest is added in the order of the maximum and the minimum. It is clear that the response will vary depending on the camera and the angle of the hand orientation.

Then, the 0PU 49 determines equation (2), and then performs the following calculation.

The result of equation (3) is i [corresponding to the control memory IJRAM
is memorized.

With the above, 0PU49 has completed the processing for 1 screen memory,
It waits for the next write completion signal to be input from the control unit 38. Then, with the input of the next write completion signal, 0PU40
starts the same process as described above for the screen memory 36, and obtains the calculation result of equation (3) regarding the value of new round 14. At this time, the previous processing result is read from the memory RAM, and the current result is The larger value for each item is re-memorized and stored in RAM as a representative value.

The present invention consists of the above-mentioned series of processing, namely, writing to the screen memory, calculating equation (3) by 0PU40, storing the calculation result in the storage RAM, and storing the calculation result and the previous processing in the storage RAM. A series of processes consisting of determining a representative value by comparison with the current calculation result, storing the representative value in the storage RAM, and processing the next screen memory are repeatedly performed.

FIG. 7 shows the screen 1=1.2.
The correspondence between the maximum and minimum values of zll for 3 is shown, and as is clear from the figure, when the y-axis of the screen becomes parallel to the finger to be measured, the middle finger in Figure 7 ,
It is understood that the maximum value is obtained.

The apparatus of the present invention performs the above processing on a rotating machine 1l12.
2 until the input/output interface 44 and the CPU 40 receive the rotation end signal. CPU4
0 receives the same signal and issues an end signal to the control unit 38 to stop writing to the memories 34 and 3g, and also issues a stop command to the rotating mechanism 22 to stop its rotational movement. cp
For σ40, read the maximum value of equation (3) from 81M,
This is outputted to an external device (not shown) via the input/output interface 7ace 44. As mentioned above, this value is the maximum representative value of each finger, and it is clear that this value corresponds to (1) 2 shown in FIG.

FIG. 8 shows the above phenomenon as a graph corresponding to six values and rotation angles. However, in the above description, the rotation mechanism 22 is arranged so that each of the famous fingers (little finger, ring finger, middle finger, O index finger) becomes a line with @ on the y-axis in any of the obtained screens. It is rotated □ to a predetermined angle and then returned to the original rotation starting position.

Furthermore, in the above explanation, the influence of the thumb was ignored, but by determining the position of the hand and the field of view of the camera, and incorporating the characteristics of the shape of the hand into the algorithm, this influence can be easily removed. It is clear that it can be done.

Although the above explanation uses a transmission type optical system, it is also possible to use a reflection type optical system as shown in FIG. At this time, the light source 14 is a diffused reflection type light source (for example, a fluorescent lamp with ground glass placed in front of it). The measuring table 12 uses a matte blackboard (felt-like material) or the like that has a sufficient contrast ratio with the hand.

However, a rotary set video camera is known in which the internal deflection device is electrically rotated by controlling an internal deflection device by an external electric signal to perform the Rusk scan by an arbitrary angle1. It is clear that the same functionality as in the embodiment can be obtained.

My father, as shown in FIG.
(4) Any position (Xo) shown in formula.

Copy a new screen memory 5o by converting coordinates (address) by rotating one angle around y・), Jin's screen/Mori 5
It is clear that the same function can be achieved by performing the above-mentioned calculation of the nine maximum and minimum values for the content of G while changing the value of angle 0.

In the above formula, (X・, y, ) is the rotation center coordinate (X
%y) is the value in K, where 0 represents the angle of the new coordinates (xl, y/) with respect to (xsy)rc.

FIG. 11 shows the state of the coordinate transformation. According to the present invention, the maximum and minimum points of the hand) are primarily determined from the Rusk image obtained using the imaging device, and the Since it is possible to measure the length of the fingers of the hand, there is no need to precisely align the fingers as in the conventional method, and there are no variations in measurement due to the way they are aligned, making it possible to measure the length of the fingers of the measurer's hand. You can do this easily and accurately.

Further, in the present invention, it is possible to use an inexpensive general-purpose video camera as the imaging device, and a more stable device can be obtained at a lower cost than in the conventional multiple sensor system.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram defining the length of a finger, FIG. 2 is a diagram showing an embodiment of the present invention, FIG. 3 is a block diagram of the image analysis device shown in FIG. 2, and FIG. 5 and 6 are diagrams for identifying the maximum and minimum points of the outline of the hand from the memory contents of the screen memory shown in FIG.
Figure 7 is an explanatory diagram showing an example of the binarized image obtained by rotating the camera, its maximum and minimum points, and the length of the finger obtained. Figure 8 is the length of the finger obtained. FIG. 9 is an explanatory diagram showing another embodiment of the present invention using the reflection method. FIG. 10 is an explanatory diagram showing the correspondence with the rotation angle. FIG. 10 is an explanatory diagram showing the correspondence with the rotation angle. FIG. 11 is a block diagram showing another embodiment of the present invention using a method of performing rotational coordinate transformation and rereading. FIG. 11 is an explanatory diagram showing a principle diagram of the rotational coordinate transformation formula. Note that corresponding members in each figure are given the same reference numerals, 18 is a video camera as an imaging device, 20 is an image analysis device,
34 and 36 are screen memories. Agent Patent Attorney Makoto Kuzuno - (#t”Illusion 2, Figure 1 tv Figure 2 Figure 4 Figure 5 RL + RL proverb Figure 6 L4213 Figure 8 λ'ma + t η Melaka 1 *

Claims (1)

[Scope of Claims] (1) An imaging device that is installed opposite the palm of the hand to be measured and that converts the optical image into an electrical rask image by raster scanning, and an image capturing device that is rotated around a predetermined image position. an image analysis device that obtains a plurality of raster images with different angles and calculates the finger length of the famous finger by determining the maximum and minimum positions of the outline of the fingers of the hand for each raster image; A finger length measuring device characterized in that the maximum finger length of the famous finger calculated by the image analysis device is the final measured value of the finger length of the famous finger. (In the device described in claim (1), the image analysis device includes a screen memory that stores the raster image signal output from the imaging device as an orthogonal, two-dimensional image signal converted into digital amounts of brightness and darkness. (sl) In the device described in any of the claims (formerly 2), the image analysis device is rotated around a predetermined image position and has a different rotation angle. A finger length measuring device characterized in that a plurality of raster images are obtained by mechanically rotating an imaging device. The image analysis device is characterized in that a plurality of raster images rotated around a predetermined image position and having different rotation angles are obtained using a vision camera type camera device that can electrically change the raster angle. (5) In the device according to any one of claims (1) and (2), the image analysis device converts the address of the screen memory and reads the nine raster images stored in the screen memory. A finger length measuring device characterized in that a plurality of rask paintings rotated around a predetermined image position and having different rotation angles are obtained when the finger is taken out.