WO2012022380A1

WO2012022380A1 - Method and device for determining the spacing between a person's eyes

Info

Publication number: WO2012022380A1
Application number: PCT/EP2010/062059
Authority: WO
Inventors: Moritz Wymann; Denis-André ZAUGG; Igor Merhar
Original assignee: Optiswiss Ag
Priority date: 2010-08-18
Filing date: 2010-08-18
Publication date: 2012-02-23

Abstract

The invention relates to the following method steps which are carried out on the basis of a digitalised image of a person's face: confirmation of the diameter and the position of the iris (4) of the first eye (2) on the image using a displaceable and size-scalable mark (6), and confirmation of the diameter of the position of the iris (5) of the second eye (3) on the image using a displaceable and size-scalable mark (6); following this, determining the lateral magnification of the image by comparing the iris diameters that have been determined with a predetermined reference value for the average actual iris diameter; and finally, determining the actual spacing (A) between the eyes by applying the lateral magnification to the determined iris position values of the image, or to their distance in the image.

Description

Method and device for determining the eye relief of persons

The present invention relates to a method and a device for determining the eye relief of a person as well as a method for providing and displaying a selection of eye distance suitable

Spectacle frames.

Glasses have in addition to the eye acuity of each user individually adapted glasses, so-called correction glasses, a spectacle frame with socket for receiving these glasses. The optical adjustment of the glasses is done individually for each eye, with the

Processing data are each intended for a glass, which is exactly in front of the center of the respective eye

must be positioned. Therefore, it is important for the preparation of the glasses for a particular eyeglass frame to know the exact eye distance, so that the contour of the glasses can be correctly tailored according to the lens frame of the spectacle frame.

Traditionally, this data is provided by a

Specialists are picked up manually, usually by the optician, who determines this data by means of measuring devices for the individual wearer of glasses. In the

However, usually only the optical data for the spectacle lenses are included, but not the necessary for the adaptation to a spectacle frame eye distance. This measure is also important in the selection of a spectacle frame, wherein the specialist conventionally determined on the basis of the determined AugenabStandes a preselection of possible, matching spectacle frames and submits to the wearer for selection.

In addition, the ordering and production of eyewear over the Internet is offered in recent times, where no direct advice and in particular no individual measurement can be made by a specialist. For example, the wearer of the glasses usually has to try to determine the value of his or her interpupillary distance in order to transfer this data to the eyewear selection and ordering system.

A method is known from US Pat. No. 6,535,223, for example, after the eye distance can be determined on the basis of a photograph of the face of the spectacle wearer with the assistance of the spectacle wearer. Here is the

Determination of relative eye distance due to

Evaluation of the photograph by a computer automatically made, whereby the editor must manually set the starting points of the distance measurement on the photograph for each eye. For this the interface of the

Program on a graphical interface, which on the one hand reflects the photograph and on the other hand the

Eyeglass wearer offers two positionable bars, which the operator laterally tangential to the on the

Photography needs to position recognizable pupils so that the eye relief is determined in relation to the photograph. The absolute eye relief is then based on the scale of photography, which can be calculated from the fact that the

Pupil diameter in humans approximates

has constant value.

The object of the present invention was to find a method of the aforementioned type, which is a simple and reliable determination of the effective

Eye distance based on a photograph resp.

Illustration of the face allowed by a user.

This object is achieved according to the invention that based on a digitized image of the face of the person, the image by a

Computer application is provided on an optical output device and wherein the computer application further comprises means for displaying and fixing points or areas on the image and having means for automatic image recognition, the following

Procedural steps are carried out:

Confirmation of the diameter and position of the first eye iris on the image with a displaceable and resizable marker;

- Confirmation of the diameter and position of the iris of the second eye on the picture with a

slidable and scalable marking; - Calculation of the imaging scale of the image by comparing the determined iris diameter with a predetermined reference value of the mean effective iris diameter; - Calculation of the effective eye distance by applying the imaging scale to the determined iris position values of the image resp. their removal in the picture.

By using a mouse, for example, on the screen above the image manually displaceable

Circle as a marker not only the diameter of the eye in the grid of digital imaging can be determined reliably and accurately, but also accurately calculate their distance in the raster after positioning over the two eyes shown in the figure. Using the ratio or quotient of the diameter in

Pitch of the drawing with the effective diameter of the iris of a person, which is equal in all accuracy for all persons, namely about 12mm, the

The image scale of the image can be calculated automatically without the need for a reference object known in its length to be present on the image. Using the imaging scale and the positions of the centers of said markers can now be easily and automatically the effective eye relief

to calculate. The calculations are carried out, for example, by a calculation module, a computer or computer. The position of the centers is, for example, in

Pixel scale of the figure recorded which a very high accuracy is achieved.

The use of a circle, for example a circle with a crosshair, ie a line pair perpendicularly intersecting in the center, is very user-friendly easy to handle and leads to very precise results. Thus, the position and the diameter of an eyelid half-covered iris can still be determined very accurately, as for a precise positioning of the circle already a relatively short, free

visible arc area of the outer edge of the iris is sufficient.

For example, before confirming the diameter and position of the iris of the two eyes on the image, an automatic pre-recognition and storage of the position of the eyes and possibly the middle of the nose is performed, these positions being used as starting positions for the scalable markings on the image. With the expert known and available

Picture recognition applications resp. programs, it is possible to recognize certain motifs on a digital image section automatically and attach an optical marking resp. represent, whose exact position is known in the figure, for example in the form of so-called pixel coordinates. Thus, the markers for the confirmation of the position and diameter of the iris of each eye can be automatically prepositioned provisionally, which usually only minor manual corrections by the user must be made. This simplifies the process and eliminates possible sources of error right from the start.

For example, the positions are stored in coordinates according to the grid size of the digital image, preferably in the pixel size of the image. This allows the calculations to determine the diameter and the distance automatically be performed, for example, with a computing module.

For example, the positions are represented by circles and a connecting line through the two eye positions, where appropriate, the position of the nose center is preferably determined as a circle with the center on this line and in addition to the

Connecting straight line axis is represented by the position of the nose center. As already mentioned,

The representation of a crosshair facilitates the manual positioning of the markers in the correct position of the image, thus giving even untrained users a high level of accuracy

Accuracy can achieve. The connecting line, which is shown as a vertical straight line in the figure, makes it easier for the user to define the middle of the nose, whereby the connecting line can also be moved manually by the user, analogous to the markings for determining the eye positions, in order to confirm the position of the nostril.

Since the eyes do not have to have exactly the same distance on both sides of the middle of the nose, this can

Information in the selection and adaptation of a

Glasses frame can be used and possibly also when

Cutting the contour of correction lenses are used for the frame of the spectacle frame, so at

Requires the center of the correction lens so that the center of the iris can be adjusted. The prerequisite for this is that the person's gaze on the digital image is at least approximately straight ahead. For example, to confirm the position and / or adjustment of the size of the mark is a separate

Illustration of a section of the eye area generated and shown, this figure preferably in

enlarged scale is displayed. This can further increase the accuracy of the positioning of the circles and their handling can be simplified.

For example, in a first step, the position and size of the right eye and in a subsequent step, the position and size of the left eye confirmed or. set. By defining the sequence, their relationship is also defined in the figure, and it is easier to detect possible incorrect positioning automatically. For example, a user may be requested to check his input and correct it if necessary.

For example, the mean of the two

Eye diameter calculated automatically and then the scale of measurement as a quotient between the reference value and the mean automatically calculated. By using the mean, positioning inaccuracies become

balanced and a more accurate value is determined. It can thus also be a plausibility check, after which if the differences between the two values are too large, a corresponding message can be generated for the user and a confirmation of the information provided can be requested.

It is further proposed according to the invention that based on the determined effective eye relief from a list With spectacle frame data, the eyeglass frames suitable for this effective eye relief are determined and offered for selection, followed by the choice of one

Glasses frame from this selection of this is shown in the picture using the picture scale. Thus, the user can directly on the picture be selected spectacle frame in the correct scale

and he can get an idea of the optical effect of his selection, as they do

conventionally only when fitting real ones

Eyeglass frames in the optician business and viewing in the mirror was possible.

For example, the representation of the spectacle frame is such that the center of the spectacle frame congruent over the determined nose center between the two

Eyes is arranged. Using the information of the position of the nib center on the connecting line between the two eyes, the selected spectacle frame can be shown not only in the correct scale but also in the correct position and angle in the figure without the user manually shifting his selection to this position until he can look at the effect.

The object is achieved according to the invention by a

Setup with an application server and over

Network connected to the application server

Workstations are solved, wherein the application server has a storage area for storing a digital image and having an image recognition application, which performs an automatic detection of the position of the two eyes and possibly the nose center in the figure. Next, the inventive device has a

An image processing application which, under the control of the workstations, displays a diameter changeable circle in the image and records and stores its position and diameter value, and performs the calculation of the scale of the image and the distance between the positions of the two eyes.

Thus, a provider or manufacturer of glasses can store the eyeglass frames offered by him centrally in a database on the application server and there also the user the image recognition and image processing applications. Programs. The user then only needs a connection to the application server via a network connection, for example via the Internet

to build a digital picture of the head too

and after manually confirming the position of the iris of the eyes on the image based on the selection list presented by the application server

Select eyeglass frames and see their optical effect on the right scale on the picture. Together with the data of a prescription for prescription eyewear it is possible to directly order and manufacture glasses which are also a suitable size

having.

It should be noted here that the term eye distance means the distance of the centers of the iris of the two eyes looking straight ahead. Continue to be automatic calculations performed by billing modules, computers or computers by the computer application.

Embodiments of the present invention will be explained in more detail below with reference to figures. Show it

Figure 1 is a schematic representation of the digital image of a head with marks of the eyes and nose center.

Fig. 2 shows the detail of an eye of Figure 1 with eye marking before the shift and

Size adjustment;

3 shows the section according to FIG. 2 after displacement and size adaptation of the eye marking to the iris;

Fig. 4 shows the representation of Figure 1 showing the displacement of the vertical mark of

Nose center;

Fig. 5 shows the illustration of Figure 1 with the correct scale Pictured and arranged

Eyeglass frame; and

Fig. 6 shows schematically the representation of the device for

Implementation of the inventive method.

In FIG. 1, the representation of the digital image of the head 1 of a person with left eye 2 and right eye 3 is shown purely schematically. For one

Reliable determination of the AugenabStandes between left eye 2 and right eye 3, the eyelids are advantageous opened and the gaze straight ahead, so that the left iris 4 and the right iris 5 appear approximately in the middle of the respective eyes 2, 3.

For real digital images, the contours are

Of course not as clearly drawn as shown in Figures 1 to 5, since for example color images are used in high resolution, the contours of the eyes 2,3 and in particular the iris 4,5 but are usually sufficiently well recognizable. Depending on the resolution of the image, the information is present, for example, in the so-called pixel format, so that any position, for example, of the face, can be determined on the basis of a coordinate. However, this pixel measure gives no indication or reference to the effective mass, i. Due to the distance A in this pixel measure between any two points, it is not possible to make any statements about the effective distance of these two points in the face. Since the method should and can be used with any mappings, neither does the effective

Image resolution nor the focal length of the used

Recording lenses and the recording distance a role, but it should be in any case to a distortion-free image.

A person skilled in the art can make a determination of the effective scale of an image, if shown in the figure

Level of the eyes a reference object with known effective dimensions is present. Such a reference object may be, for example, a coin of known dimensions, which when taking the image in the facial area is arranged, for example, by pressing the coin to the forehead or chin, but then neither the eyes nor the coin may be covered as a whole.

On the other hand, a reference object directly present in the image represents the iris, which is known to have an approximately constant diameter of approximately 12 mm in all persons, and can therefore be used as a reference value. Now if the diameter of the iris in the

Image Resolution, the scale of the image can be calculated as the quotient between this diameter and the reference value, and thus all distances or positions in the image at effective distances

be converted. This conversion can be done easily and automatically, for example, computer-aided. According to the invention, the size of the iris 4, 5 now becomes one

Eye 2, 3 determined by the fact that the user a covering shown in the figure optical marking 6 covers the iris 4, 5 placed.

The optical marking 6 is formed, for example, as a reticle with a circle and can be, for example, predetermined by the application application manually move the mouse of a computer and change in diameter.

FIG. 2 shows the starting position of the optical marking 6 in the region of an eye 2. A simplification of the operation by the user can be created by giving him this image section for the

Positioning and customization in a separate window magnified will be displayed on the screen of a computer. The home position of the marker 6 has been set, for example, based on the result of automatic image recognition.

By moving and pulling the marker 6 has been moved manually covering the iris 4, as shown in Figure 3. This position can now be confirmed by the user, on the one hand the diameter of the iris 4 is determined in the resolution of the image, such as

additionally through the center of the mark 6

On the other hand, the exact center of the iris 4 is determined in the figure.

This step is performed for both eyes 2, 3, whereby the exact position of both eyes 2, 3 in the

Resolution of the image can be confirmed as well as the diameter of the iris 4, 5 is determined twice.

Thus, the effective scale of the image can now be determined and, for example, by averaging the two diameters of the iris 4, 5 an accurate determination of the effective eye relief of the two eyes 2, 3 resp.

more precisely, the iris 4, 5 of the two eyes 2, 3

carry out .

The use of a marker 6 in the form of a

Reticle with ring also makes it possible to perform an accurate and reliable determination of the eye distance, if in the image used not both eyes 2, 3 are clearly shown, as is the case in the illustrated schematic figures. Even with a partially concealed iris 4, 5 can be both the diameter and the position of the center with good Detect accuracy, since the iris 4, 5 has a circular outer contour, and thus already a small

A section of this contour is sufficient to correctly position the marker and to correctly align it in size. By comparing the values of the two eyes 2, 3, an additional control of the values can take place and, in the case of excessively large deviations, a corresponding message for the user can be generated for a new test, since the diameter values may practically not differ.

This means that any incorrect entries can already be intercepted by the application.

FIG. 4 once again shows the illustration according to FIG. 1

shown, in which case the horizontal axis 7, which leads through the centers of the iris 4, 5 of the two eyes 2, 3, is shown, as well as the vertical axis 8, the nose center axis respectively. to show the facial axis. Again, the user can be given the opportunity to manually move this axis horizontally and thus in the correct position (shown in dashed lines)

position and thus the nose center 9 to

define.

Based on the database mentioned above, a selection of suitable models of spectacle frames can be made available to the user with this information. After selecting a model 10, this can now be done on the correct scale, and on acquisition of the

Nasenmittelpunktes 9 also in the correct position, are shown in the figure, as Figure 5 shows. This gives the user the same visual impression of his choice mediates, for example, when visiting an optician's business and selecting from real life

Can experience eyeglass frames.

The model 10 shown in Figure 5, for example, also manually by the user with the help of

Computer mouse moves resp. be positioned to determine the desired position of the frame with respect to the eyes 2, 3. These data can now directly in relation to the positions of the eyes 2, 3 resp. Irises 4, 5 are set and thus the cutting of the contour of the spectacle lenses in the raw form for the version of the model 10 of the spectacles are fixed, thus the focal point of the finished

tailored spectacle lenses according to the selection of Figure 5 is positioned.

The advantage of this selection lies in the fact that all preferred models can be displayed regardless of their effective availability and in the correct size and on the other hand that as a user even the wearer can make this selection directly, without necessarily requiring the assistance of a specialist and so that a visit to the optician in the selection of a new spectacle frame can be avoided with existing, valid optical prescription.

Based on the data thus determined, the selection of the user and the recording of the data of a spectacle prescription with optical information on prescription lenses, a suitable spectacle can be directly used by the spectacle wearer

Manufacturers are ordered and manufactured and supplied by the manufacturer. FIG. 6 shows, purely schematically, the structure of a device with which the described method can be carried out. In one

Application server 11, a memory area 12 and an application area 13 are arranged. The application server 11 is connected to workstations 15 via a network 14, the network 14 may be, for example, the Internet.

In the memory area 12, for example, the database with data of spectacle frames is arranged. in the

Application area 13 are, for example, the programs for communication with the workstations as well

Picture recognition and image processing programs available as well as billing applications for the implementation of

Calculations of the scale and the distances and positions of the markings, as described above.

About the workstations 15 are the inputs of

User made, in particular, is connected to the

Workstations connected computer mice the

Shifting the marks and confirming the

Positions made.

Claims

claims

1. A method for determining the eye relief of a person based on a digitized image of the face of the person, wherein the image by a

Computer application is provided to an optical output device, wherein the computer application further comprises means for displaying and fixing points or areas on the image and having means for automatic image recognition, characterized

in that the following method steps are carried out:

- Confirmation of the diameter and position of the iris

(4) of the first eye (2) on the image with a displaceable and size-scalable marker (6);

- Confirmation of the diameter and position of the iris

(5) of the second eye (3) on the image with a displaceable and resizable marker (6);

- Calculation of the imaging scale of the image by comparing the determined iris diameter with a predetermined reference value of the mean effective iris diameter;

- Calculation of the effective eye distance by applying the imaging scale to the determined iris position values of the image resp. their removal in the picture.

2. The method according to claim 1, characterized in that before confirming the diameter and position of the iris (4, 5) of the two eyes (2, 3) in the figure, an automatic pre-detection and storage of the position of the eyes (2, 3) and possibly the nose center (9) is performed, and these positions are used as starting positions for the scalable markers (6) in the figure.

3. The method according to claim 1 or 2, characterized

characterized in that the positions in coordinates

stored according to the grid size of the digital image, preferably in the pixel size of

Illustration .

4. The method according to any one of claims 1 to 3, characterized in that the markings (6) with circles and a connecting line (7) through the two

Eye positions are shown, where appropriate, the position of the nose center (9) preferably as a circle with

Center is defined on this straight line (7) and in addition to the connecting line vertical axis (8) by the position of the nose center (9) is shown.

5. The method according to any one of claims 1 to 4, characterized in that for the confirmation of the position and / adjustment of the size of the marking (6) a separate image of a section of the eye area is generated and displayed, is preferably shown in an enlarged scale.

6. The method according to any one of claims 1 to 5, characterized in that in a first step, the position and size of the right eye (2) and in a subsequent step, the position and size of the left eye (3) confirms resp. is set.

7. The method according to any one of claims 1 to 6, characterized in that the mean value of the two

Eye diameter of the image is calculated automatically and then the scale of measurement is calculated automatically as a quotient between the reference value and the mean value.

8. The method according to any one of claims 1 to 7, characterized in that based on the determined

effective eye distance (A) from a list of data of eyeglass frames for this effective eyepoint (A) suitable eyeglass frames (10) determined and offered for selection and after selecting a spectacle frame (10) from this selection this in the figure using the imaging scale is pictured.

9. The method according to claim 8, characterized in that the representation of the spectacle frame (10) takes place such that the center of the spectacle frame (10)

is arranged congruently above the center (9) between the two positions of the eyes (2,3).

10. Device for carrying out the method according to one of claims 1 to 9 with an application server (11) and via a network (14) to the application server (11) connected workstations (15), characterized in that the application server (11) has a memory area (12) for storing a digital image and has an image recognition application, which automatically detects the position of the two eyes (2,3) and possibly the nose center (9) in the figure, and an image processing application which, under the control of the workstations (15), has an image processing application

Diameter changeable circle as marking (6) in the figure represents and its position and diameter value captures and saves and the calculation of the

Mapping scale and the distance between the

Perform positions of the two eyes.

11. Use of the method according to claim 1 to 10 and a device according to claim 11 for providing a selection aid for the order of spectacles.