JP5351704B2 - Image sickness tolerance evaluation apparatus and program - Google Patents

Description

  The present invention relates to an image sickness tolerance evaluation apparatus, and in particular, evaluates an image sickness resistance (image sickness resistance) of an observer who is watching a motion video that is likely to cause image sickness in a video viewed on a television or a computer monitor. The present invention relates to a video sickness tolerance evaluation apparatus and program.

Symptoms such as motion sickness that occur when observing upset video are called video sickness. Motion sickness corresponds to motion sickness such as car sickness and sea sickness, and is known to be caused mainly by stimulation of the vestibular system by passive motion of the observer himself. On the other hand, video sickness is caused by motion sickness. Video sickness may include VR (Virtual Reality) sickness and simulator sickness. However, when the sitting chair moves and causes stimulation of the vestibular system, it is not included in video sickness and is treated separately. It has been broken.
In recent years, with the increase in the size of home TV screens, the risk of motion sickness is said to increase, and in order to prevent or reduce this risk, what video and viewing environment can cause motion sickness. There is a lot of research into whether it is easy to cause.

  As a method for evaluating the degree of video sickness, for example, a subjective evaluation method based on 16 question items related to sickness symptoms such as SSQ (Simulator Sickness Questionnaire) (Non-patent Document 1) or the autonomic nervous system due to sickness An objective evaluation method has been proposed in which a change in the above is evaluated by obtaining a maximum cross-correlation coefficient between blood pressure and heart rate in the frequency band of heart rate variability (Non-Patent Document 2). With these evaluation methods, we know that images containing many qualitative camera motions such as camera shake, rotation, rapid pan, rapid zoom, and fast camera movement are prone to motion sickness. Yes.

In addition, as a qualitative feature quantity that is prone to image sickness, a report that the number of people who are motion sickness increases when an image in which the motion direction of the entire screen changes randomly at random timing (Non-Patent Document 3), There is a report (Non-patent Document 4) that, when the entire motion direction cannot be predicted, the number of people who are motion sickness increases compared to the case where prediction is possible.
Then, when eye movements of people who are prone to image sickness and people who are not prone to video sickness are measured when watching a swaying image, the mutual motion component of the whole screen and the motion component of eye movements “Correlation” sometimes becomes lower than the cross-correlation of people who are not prone to image sickness, and there is a report that the physical characteristics of the swaying video in that section were features that are prone to video sickness (Non-patent Document 5) .

R.S.Kennedy, N.E.Lane, K.S.Berbaum: “Simulator Sickness Questionnaire: An Enhanced Method for Quantifying Simulator Sickness”, The International Journal of Aviation Psychology, 3, 3, pp.203-220 (1993) Norihiro Sugita, Makoto Yoshizawa, Akira Tanaka, Kenichi Abe, Tomoyuki Yamake, Shinichi Nita, “Evaluation of biological effects of video stimulation using the maximum cross-correlation coefficient between blood pressure and heart rate”, Journal of Human Interface Society, vol.4, no.4, pp.227-234 (2002) Kenmitsu Harazawa, Naoyuki Matsubuchi, Hiroaki Shigeru, Etsuko, Toshiya Morita, Takayuki Ito, Takahiro Saito, Takao Sato, Kiyoharu Aizawa, “Effects of changes in motion direction of video on sickness”, 2005 Tournament, 21-3 (2005-8) Matsuyuki Naoyuki, Reiko, Harazawa Kenmitsu, Shigehiro Hiroaki, Kawashima Takayuki, Morita Toshiya, Ito Takayuki, Saito Takahiro, Sato Takao, Aizawa Kiyoharu, “Effects of visual cues on video motion on video sickness”, Video Information Media Annual Conference 2004 Winter Conference 11-3 (2004-12) "Standard Certification Research and Development Project Standardization of Biosafety Evaluation Method for Video 2005 Results Report", National Institute of Advanced Industrial Science and Technology

However, according to the conventional method, it is only possible to know whether or not the shaking image having the qualitative characteristics seen by the subject is an image in which video sickness is likely to occur. Also, even in the same upset video, the degree of video sickness varies depending on the viewer, and there were individual differences.
In the conventional method (Non-Patent Document 2), first, by self-reporting, it is divided into two groups of people who are prone to video sickness and people who are prone to video sickness. Quantification was performed. For this reason, there is a problem that the range of the feature amount also has a large variation due to individual differences.
This problem is based on self-reporting as to whether or not video sickness is likely to occur. Therefore, instead of self-reporting, it is necessary to express the ease of motion sickness of each observer who has seen a swaying video as a numerical value, and that value should be used as a criterion for determining whether or not the motion sickness is likely to occur.

  In addition, from the report of Non-Patent Document 4, a person who is prone to video sickness is not good at predicting the motion of the entire screen in the motion video, so the gaze is the motion of the entire screen in the motion video that is difficult to predict motion. I cannot follow. Therefore, it is considered that a person who is prone to image sickness is likely to cause (causes) image sickness because he or she cannot stably display a moving image on the retina. However, there is no disclosure of a method for determining whether or not a subject is a person who is prone to video sickness by measuring the follow-up motion (tracking characteristics) of a line of sight with respect to a shaking image that is difficult to predict motion.

  The present invention has been made to solve the above problems, and is an index for determining whether or not an observer's eye movement showing followability to an image that is difficult to predict motion is a person who is prone to image sickness. It is an object of the present invention to provide a video sickness tolerance evaluation apparatus that calculates a numerical value for evaluating the difficulty of video sickness of an observer (video sickness tolerance).

  In order to solve the above problem, the motion sickness tolerance evaluation apparatus according to claim 1 of the present invention measures an angle of rotation of an eyeball of an observer who is watching a shaking image displayed on a screen of a display device, A motion sickness tolerance evaluation device for calculating a numerical value for evaluating the motion sickness tolerance of the observer, comprising: a still image storage means, a movement information generation means, a motion video generation means, a video display means, and a gaze measurement And a mismatch degree calculation means.

According to such a configuration, the motion sickness tolerance evaluation apparatus generates visible region movement information for randomly moving the visible region, thereby sequentially acquiring images in the visible region that moves randomly, and motion prediction is performed. Generates upset images that are difficult to perform.
In addition, the motion sickness tolerance evaluation device indicates an angle of rotation of the observer's eyeball obtained by measuring the eyeball movement (tracking movement of the line of sight) of the observer who is watching the shaking image displayed on the display device. A numerical value (degree of inconsistency) for evaluating the video sickness tolerance of the observer is calculated from the measured visual angle value and the expected visual angle value in which the movement amount of the visible region is represented by an eyeball rotation angle. This discrepancy is determined by the position on the screen (gazing start position) that the observer gazes at the beginning of the time interval and the position on the screen that the observer gazes at the end of the time interval (gazing end). Position), and further, the distance to the gaze end position when the position of movement (movement destination position) where the motion video actually moved within the time interval from the gaze start position was calculated, This corresponds to the amount of deviation from the distance to the destination position.

  With this configuration, by measuring the angle at which the observer's eyeball has rotated with respect to images that are difficult to predict motion, it is possible to obtain data on the observer's eye movements, and whether the rotation angle of the eyeball is likely to cause motion sickness. As an index for determining the image, a numerical value (degree of disagreement) for evaluating the video sickness tolerance of the observer can be calculated.

  Further, the motion sickness tolerance evaluation device according to claim 2 is the motion sickness tolerance evaluation device according to claim 1, wherein the still image generation means for generating the still image stored in the still image storage means; The image processing apparatus further includes an implementation environment storage unit that stores a viewing distance from the observation position of the observer to the screen of the display device and a screen size of the display device, and the still image generation unit includes a still image of a predetermined pattern Is generated in accordance with the viewing distance and the screen size of the display device, and the still image having a constant spatial frequency component regardless of the observation position of the observer and having a size larger than the screen size of the display device is generated. It is characterized by doing.

  In such a configuration, the motion sickness tolerance evaluation device generates a still image having the same spatial frequency even when the screen size and viewing distance of the display device are different by the still image generation means.

  The motion sickness tolerance evaluation device according to claim 3 is the motion sickness tolerance evaluation device according to claim 2, wherein the movement information generating means is configured such that the movement direction of the visible region changes randomly at a random timing. The moving on the screen of the display device calculated from the area movement direction information, the viewing distance, and a predetermined eyeball rotation relative speed obtained by randomly displacing a preset reference eyeball rotation speed within a predetermined range. The visible area movement information including the visible area movement speed of the visible area is generated.

  In such a configuration, the motion sickness tolerance evaluation apparatus provides a motion image that is difficult to predict motion, in which the moving direction of the visible region changes randomly at random timing, and the moving speed also changes randomly.

  The motion sickness tolerance evaluation device according to claim 4 is the motion sickness tolerance evaluation device according to any one of claims 1 to 3, wherein the mismatch degree calculation means calculates the expected viewing angle value, For each unit time, it is calculated from the amount of movement of the visible region and the viewing distance, a unit time mismatch is calculated from the difference between the measured viewing angle value and the expected viewing angle value, and the shaking image is displayed. The mismatch degree is calculated from the sum of the unit time mismatch degrees within the time.

  In such a configuration, the motion sickness tolerance evaluation apparatus calculates an expected viewing angle value indicating an eyeball rotation angle required to reach the moving destination of the visible region from the moving amount of the visible region and the viewing distance, and the eye movement of the observer The discrepancy is calculated by subtracting the measured viewing angle value that is the actual rotation angle of the eyeball calculated from the above and the expected viewing angle value.

  The video sickness tolerance evaluation apparatus according to claim 4 further stores a video sickness tolerance evaluation unit that calculates an evaluation value that the video sickness tolerance of the observer is lower as the degree of mismatch is larger, and the evaluation value is stored. And an evaluation result storage means.

  In this configuration, the video sickness tolerance evaluation apparatus calculates an evaluation value indicating the video sickness tolerance of the observer from the degree of inconsistency, and stores the evaluation values of many observers in the evaluation result storage unit.

  The motion sickness tolerance evaluation device according to claim 5 is the motion sickness tolerance evaluation device according to claim 4, wherein the measured visual angle value measured by the visual line measuring means is a preset reference eyeball rotation angle value. Jumping movement determining means for determining that jumping eye movement has occurred when the jumping eye is exceeded, and the discrepancy degree calculating means is set to a predetermined predetermined value after the jumping movement determining means determines that jumping eye movement has occurred. The unit time non-matching degree up to the time is not calculated.

  In such a configuration, the motion sickness tolerance evaluation device does not calculate the unit time mismatch when the jumping eye movement (saccade) occurs.

The video sickness tolerance evaluation apparatus according to the present invention has the following excellent effects.
According to the first aspect of the present invention, the gaze position where the observer is looking on the screen measured by the line-of-sight measuring means at a certain point in time and the position of the gaze target point on the image determined by the observer The degree of inconsistency corresponding to the amount of deviation can be calculated.
This amount of deviation (degree of disagreement) is a numerical value related to the tracking movement of the line of sight, which means that an observer with a small degree of inconsistency can follow a moving image, and conversely, an observer with a large degree of inconsistency Will not be able to follow.
Therefore, an image sickness tolerance evaluation apparatus can determine that an observer with a high degree of inconsistency is likely to cause image sickness.

  According to the second aspect of the present invention, since the room size, the screen size of the display device, and the like are different, a still image having the same spatial frequency is generated even in an implementation environment with different viewing distances. Can present a swaying video that looks the same. In addition, it is possible to display a coarse and swaying image on the screen according to the observation position in consideration of the visual acuity of the observer. Therefore, variation due to the influence of the implementation environment can be suppressed.

  According to the third aspect of the present invention, since the observer views a motion image that is difficult to predict motion, it is possible to measure the following motion of the line of sight with respect to the motion image that is difficult to predict motion.

  According to the fourth aspect of the present invention, the movement destination of the visible region is reached from the actual rotation angle (measured viewing angle value) of the eyeball calculated from the eyeball movement of the observer, the movement amount and the viewing distance of the visible region. Therefore, since the degree of inconsistency can be calculated from the eyeball rotation angle (expected viewing angle value) necessary for this, it is not necessary to calculate the actual viewpoint position of the observer on the screen of the display device. Therefore, it is possible to shorten the processing time required to calculate a numerical value for evaluating the observer's image sickness tolerance as compared with the conventional case.

According to the fourth aspect of the present invention, it is possible to calculate an evaluation value indicating the video sickness tolerance of the observer from the degree of mismatch.
Further, by using the invention described in claim 4, it is also possible to compare the evaluation value of the observer with a large number of evaluation values (past data) stored in the evaluation result storage means.

  According to the fifth aspect of the present invention, the jumping eye movement that occurs when the object to be viewed is mainly changed instead of following the video, the tracking of the line of sight with respect to the swaying video as an index in the video sickness tolerance evaluation device. Since the movement is different from the movement, the eye movement of the observer other than the jumping eye movement can be measured.

It is a block diagram of the image sickness tolerance evaluation apparatus which concerns on this invention. (A) is a diagram showing a still image that is created when a short viewing distance L _1. (B) is a diagram showing a still image that is created for long viewing distance L _2. (A) It is a figure which shows the moving distance (Ds) of a visible region, and the moving distance (de) of an actual observer's viewpoint. (B) It is a figure which shows the eyeball rotation angle (expected visual angle value (theta) s) required in order to reach | attain a movement destination, and an actual eyeball rotation angle (measured visual angle value (theta) e). It is a flowchart of the processing operation of the image sickness tolerance evaluation apparatus which concerns on this invention.

(First embodiment)
Next, the first embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
[Configuration of the video sickness tolerance evaluation apparatus 1]
FIG. 1 is a block diagram of a video sickness tolerance evaluation apparatus. As shown in FIG. 1, the video sickness tolerance evaluation apparatus 1 includes a still image generation unit 11, a movement information generation unit 12, a motion video generation unit 13, a video display unit 14, and a line-of-sight measurement unit 15. Degree calculation means 16, video sickness tolerance evaluation means 17, evaluation result storage means 18, still image storage means 19, and implementation environment storage means 20. The motion sickness tolerance evaluation device 1 is connected to the display device 2 so as to be able to display a video, and the motion sickness tolerance evaluation device 1 is connected to the eyeball photographing device 3 so that data can be acquired.
The observer V looks at the image displayed on the display device 2 in front of the screen of the display device 2, and the observation position of the observer V and the screen of the display device 2 are separated by a viewing distance L. .

[Display device 2]
The display device 2 is a device that displays an image transmitted from the image display means 14 described later on a screen, and is, for example, an LCD (Liquid Crystal Display). The display device 2 may be built in the video sickness tolerance evaluation device 1.

[Eyeball photographing device 3]
The eyeball photographing device 3 is a device for photographing the eyeball of the observer V by using the sclera reflection method and the cornea / pupil reflection method used for general eye movement measurement, and is easy to photograph the eyeball of the observer V. It is installed at a position (for example, installed in front of the observer V, or installed in goggles worn by the observer V), and the eyeball is photographed with an infrared camera by irradiating the eyes with infrared rays. Then, the eyeball photographing apparatus 3 sends the eyeball image data obtained by photographing the eyeball to the line-of-sight measurement means 15 described later.

[Implementation environment storage means 20]
The implementation environment storage unit 20 displays the screen of the display device 2 from information (such as the screen size of the display device 2 and video signal conversion data) for displaying an image on the display device 2 and the observation position of the observer V measured in advance. It is means for storing information related to the implementation environment (implementation environment information) such as the viewing distance L.
As the implementation environment information, a plurality of combinations having different screen sizes and visual distances L may be stored in the implementation environment storage unit 20 in advance, or the user of the present invention is shown connected to the video sickness tolerance evaluation apparatus 1. The operating environment storage unit 20 may store the input unit (such as a mouse or a keyboard) that is not used. By operating this input means, the user can freely change the viewing distance L.

[Still image generation means 11]
The still image generation unit 11 acquires information related to the implementation environment such as the screen size of the display device 2 and the viewing distance L from the observation position of the observer V to the screen of the display device 2 from the implementation environment storage unit 20. This is a means for generating a still image and storing the still image in a still image storage means 19 to be described later.

The still image generating means 11 generates a still image I shown in FIG. The size of the still image I is sufficiently larger than the screen size of the display device 2. For example, the screen size of the display device 2 is the size indicated by the visible region W shown in FIG. 2, and the size of the still image I is the visible region when the visible region W moves on the still image I. It is generated in a sufficiently large size so that it cannot be within the W region.
Here, the still image generation means 11 stores the still image I (I ₀ ) of the initial pattern in advance, and based on the viewing distance L so as to have a preset spatial frequency, the still image of the initial pattern The still image I (I ₁ ) is generated by enlarging or reducing (roughening) I ₀ .

<Spatial frequency>
Here, the spatial frequency indicates the number of repetitive patterns included in the unit length. In visual research, the spatial frequency is indicated by the number of repetitive patterns included in the unit length, with the length on the screen (still image I) corresponding to an angle of 1 ° from the center of the eyeball as the unit length. Yes, the unit is cycle / deg.
For example, in FIG. 2A, a combination of a black pattern (dark) and a white pattern (bright) of the checkerboard pattern is taken as one pattern, and T patterns have a length on the still image I corresponding to the angle θ. The spatial frequency when T is included is T / θ (cycle / deg). Here, when θ = 1 °, that is, when the eyeball rotates 1 °, the viewpoint moves d ₁ on the screen of the display device 2. At this time, in FIG. 2A, since the viewpoint on the screen moves by one cycle, the spatial frequency of the still image I ₁ (checkerboard pattern) displayed on the display device 2 is 1 cycle / deg. is there. That is, based on the spatial frequency set to 1 cycle / deg, the still image I _{1 in} FIG. 2A and the still image I _{2 in} FIG. 2B are created checkerboard patterns.

Here, an example in which the still image generation unit 11 generates the still image I of the checkerboard pattern will be described with reference to FIG.
The still image generating means 11 uses the equation d ₁ / T = L ₁ · tan (θ / T), as shown in FIG. 2A, at a distance d ₁ when θ = 1 °, = A checkerboard pattern (still image I ₁ ) in which a black pattern and a white pattern for one cycle are arranged is generated.

At this time, the still image generating means 11 reduces the checkerboard pattern (still image I ₀ ) of the initial pattern (finely checks the checker pattern) or enlarges (checker pattern eye) according to the value of the distance d _1. The still image I ₁ (I ₂ ) may be generated.
The still image I ₁ (I ₂ ) has a sufficiently large size such that a region without an image cannot be within the region of the visible region W when the visible region W moves on the still image I ₁ (I ₂ ).

By the above, when closer to the viewer V screen viewing position of the display device 2 of the as shown in FIG. 2 (a) (viewing distance L is short), the finer grid checkerboard (reduced still image I ₀₎ Further, when the screen is far from the screen as shown in FIG. 2B (the viewing distance L is long), the checkerboard grid is coarsened (the still image I ₀ is enlarged), so that the still image generating means 11 Even if the distance L is different, still images I (I ₁ , I ₂ ) having the same spatial frequency can be generated.
Note that the still image I is not limited to those shown in FIGS. 2A and 2B, and is arbitrarily generated depending on the relationship between the viewing distance L and the spatial frequency.

Note that the still image I generated by the still image generating means 11 may be a checkerboard pattern shown in FIG. 2 or a random dot pattern, and preset spatial frequencies are set in the vertical and horizontal directions. And still images satisfying
Further, the still image I may include a fixed viewpoint (mark) for the observer V to watch. Thereby, a fixed viewpoint can be made into a gaze target point. In addition, by telling the observer V that he / she is looking at the fixed viewpoint, the point at which the observer V gazes during the motion video presentation is not changed freely. Measurement of rotational motion can be eliminated.

<Random dot pattern>
In addition, the combination of the black pattern and the white pattern in the still image of the random dot pattern is on the viewpoint movement line segment on the screen of the display device 2 when the eyeball of the observer is rotated 1 ° in the vertical direction or the horizontal direction. The total number of spatial frequencies is arranged, and the total distance through which the viewpoint movement line segment passes through the black pattern and the total distance through which the viewpoint movement line segment passes through the white pattern coincide with each other. The still image generating means 11 enlarges or reduces the still image I ₀ of the initial pattern of the random dot pattern to generate a still image I (I ₁ ).

[Still image storage means 19]
Returning again to FIG. The still image storage unit 19 is a unit that stores the still image generated by the still image generation unit 11.

[Movement information generation means 12]
The movement information generation unit 12 acquires information related to the implementation environment such as the screen size of the display device 2 and the viewing distance L from the observation position of the observer V to the screen of the display device 2 from the implementation environment storage unit 20. This is a means for generating the visible area W and visible area movement information.

<Generation of visible region W>
The movement information generation unit 12 generates a visible region W having the same size as the screen size of the display device 2. The image in the visible region W is displayed on the screen of the display device 2 by the video display means 14 described later.

<Generation of visible region moving speed>
Movement information generating means 12, the reference eye rotation angular velocity omega _x previously determined, a random timing, and generates a prescribed eye rotation relative velocity [Delta] [omega _x which is increased or decreased in rotational angular velocity omega _r of a predetermined range (defined Eyeball relative angular velocity Δω _x = reference eyeball angular velocity ω _x + rotational angular velocity ω _r within a predetermined range).
Here, the reference eyeball rotation angular velocity ω _x is an eyeball rotation speed (eyeball rotation angle per unit time) that is easily caused by an observer watching a moving image, and is represented by an angular velocity (deg / sec). Then, the prescribed eye rotation relative angular [Delta] [omega _x, with reference to the reference eye rotation angular velocity omega _x, shows a range of prescribed eye rotation relative velocity [Delta] [omega _x of movement information generating means 12 can take.
For example, when the rotation angular velocity ω _r = −1.0 to +1.0 (deg / sec) in a predetermined range and the reference eyeball rotation angular velocity ω _x = 5.0 (deg / sec), the movement information generation unit 12 Specified eye rotation relative angular velocity Δω _x = 4.5 (deg / sec) at a certain random timing at a rotational angular velocity ω _r within a predetermined range, for example, by 0.5 (deg / sec). ) Is generated. Similarly, at the next random timing, the movement information generation means 12 is shifted by, for example, 0.8 (deg / sec) at a rotation angular velocity ω _r within a predetermined range from the reference eyeball rotation angular velocity ω _x ( A specified eye rotation relative angular velocity Δω _x = 5.8 (deg / sec) is generated.
Then, the movement information generation unit 12 and the specified eyeball rotation relative angular velocity Δω _x whose speed changes at this random timing, and the viewing distance L from the observation position of the observer V to the screen of the display device 2 (implementation environment storage unit 20 The visible region moving speed Δv of the visible region W that moves on the screen of the display device 2 is generated using, for example, a trigonometric function.

<Generation of visible region movement direction information>
Further, the movement information generation means 12 generates visible area movement direction information R for changing the movement direction of the visible area W at random timing. This visible region movement direction information R is indicated by an arbitrary angle of 0 to 360 degrees.
The visible region movement direction information R may be indicated by a vector obtained by combining movement velocity components in the x-axis direction and the y-axis direction that are randomly generated on the xy coordinate plane.

  Then, the movement information generation unit 12 generates visible area movement information including the visible area movement speed Δv and the visible area movement direction information R. Based on this visible area movement information, the visible area W changes its moving direction at random timing and further changes its speed at random timing.

  Here, the random timing is a timing at which it is difficult for the observer V to predict when the visible region W whose movement speed or movement direction has been changed next changes the movement speed or movement direction. This is based on pseudo-random numbers generated by the random number generation means.

[Fluctuation image generation means 13]
The motion video generation unit 13 acquires the still image I from the still image storage unit 19, and further, from the movement information generation unit 12, the visible region W and the movement direction (visible region movement direction information R) and movement of the visible region W. Visible region movement information including speed displacement (visible region movement speed Δv) is acquired. Then, the visible area W is moved on the still image I based on the visible area movement information, and images within the moving visible area W (part of the still image I) are sequentially acquired and visualized. This is a means for generating a shaking image.

Here, the shaking image generated by the shaking image generation means 13 will be described with reference to FIG.
First, the motion video generation unit 13 arranges the visible region W at an arbitrary position on the still image. Then, to acquire an image of the region of the visible region W after placement (W _1). Next, the shaking video generation unit 13 moves the visible region W based on the visible region movement information (movement direction and movement speed). For example, to move the visible area W in the direction of the arrow shown in D _1. Then, an image in the moving visible region W is also acquired at an arbitrary timing (image acquisition process). In other words, the swaying video generation unit 13 repeats this image acquisition process, and generates a swaying video by visualizing the continuation of the acquired images in the visible region W.

[Video display means 14]
The video display unit 14 acquires information (such as the screen size of the display device 2 and video signal conversion data) for displaying a video on the display device 2 from the implementation environment storage unit 20, and the shaking obtained from the shaking video generation unit 13. This is means for displaying video on the display device 2.

[Gaze measurement means 15]
The line-of-sight measurement means 15 acquires eyeball image data from the eyeball photographing device 3, extracts the position of the pupil, and further derives the movement of the pupil from the continuation of the eyeball image data, so that the observer watching the shaking image This is means for measuring the rotation angle (measured viewing angle value θe (FIG. 3B)) of the V eyeball. The line-of-sight measurement means 15 extracts the position of the eyeball itself from the eyeball image data acquired from the eyeball photographing device 3, and in a predetermined time interval t, the position on the screen (gazing) at which the observer V gazes at the beginning of the time interval. (Start position) and a position on the screen (gaze end position) at which the viewer V gazes at the end of the time interval are calculated. From these calculated positions, the movement of the eyeball itself is derived from a series of eyeball image data, and the observer V is gazing, including the movement of the head (head movement) of the observer V who is watching the shaking image. The amount of change in the place (gaze start position to gaze end position) is measured. This amount of change is the measured viewing angle value θe.

[Inconsistency calculation means 16]
The discrepancy degree calculating unit 16 obtains the measured viewing angle value θe for each video frame of the shaking video from the line-of-sight measuring unit 15, and further obtains the visible area movement information for each video frame of the shaking video from the shaking video generating unit 13. . Then, from the amount of movement of the shaking image in a predetermined time interval t that can be calculated from the visible region movement information (movement direction and movement speed), and the separation distance (viewing distance L) between the observer V and the screen of the display device 2, An expected viewing angle value θs (FIG. 3B) representing the amount of movement of the swaying image expressed by the rotation angle of the eyeball (that is, the eyeball rotation angle necessary to reach the movement destination position) is measured, and the measured viewing angle This is a means for calculating the degree of inconsistency from the value θe and the expected viewing angle value θs.

Here, the mismatch degree ε calculated by the mismatch degree calculation unit 16 will be described with reference to FIGS.
The mismatch degree calculation means 16 obtains visible area movement information (movement direction and movement speed) from the motion video generation means 13 and calculates the movement distance Ds of the visible area. Then, based on the moving distance Ds of the visible region and the viewing distance L from the observation position of the observer V to the screen of the display device 2, an expected viewing angle value θs that is an eyeball rotation angle necessary to reach the moving destination. Is calculated by, for example, the trigonometric function tan θs = Ds / L. Further, the mismatch degree calculation unit 16 acquires a measured viewing angle value θe (actual eyeball rotation angle) from the line-of-sight measurement unit 15. Then, a mismatch degree Δε (= | θe−θs |) per unit time between the measured viewing angle value θe and the expected viewing angle value θs is calculated.

Then, the mismatch degree calculation means 16 calculates a mismatch degree Δε per unit time for each video frame within a preset motion video display time, and calculates a mismatch degree ε by summing them.
Further, the mismatch degree calculation means 16 does not calculate the mismatch degree ε when the eyeball rotation angle cannot be measured due to blinking or the like.

[Video sickness tolerance evaluation means 17]
The video sickness tolerance evaluation means 17 acquires the mismatch degree ε from the mismatch degree calculation means 16 and calculates an evaluation value indicating the video sickness tolerance of the observer V by a predetermined calculation method. And it is a means to memorize | store an evaluation value in the evaluation result memory | storage means 18 mentioned later. This evaluation value is a value that is evaluated as being more prone to video sickness as the mismatch degree ε is larger.

For example, the evaluation value may be an evaluation value by calculating an average value of the degree of inconsistency ε per unit time. Alternatively, the degree of inconsistency ε is quantized to classify video sickness tolerance, and the class is numerically calculated. The evaluation value may be used as an evaluation value, or may be calculated by comparing with data stored in the evaluation result storage means 18 (evaluation values of many observers measured in the past).
Then, the evaluation value calculated at this time may be stored in the evaluation result storage means 18 in association with the identification information for identifying the still image I ₀ of the initial pattern that is the basis of the shaking image viewed by the observer V. Good.

[Evaluation result storage means 18]
The evaluation result storage means 18 is a means for storing an evaluation value indicating the video sickness tolerance of the observer V. For example, the evaluation result storage means 18 identifies the still image I ₀ of the initial pattern that is the basis of the shake video viewed by the observer V. The evaluation value is stored together with the information.

  The motion sickness tolerance evaluation apparatus 1 is configured by a general computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a HDD (Hard Disc Drive), and the like (not shown). And can be operated by a program that causes the computer to function as each of the means described above.

<When it is not necessary to provide the still image generation means 11>
The still image storage means 19 stores the still image I stored in a storage medium (such as an optical disk or a USB memory) via data input means (such as an optical disk reader or a USB port) (not shown) provided in the video sickness tolerance evaluation apparatus 1. It may be memorized. And when the still image I is memorize | stored from the data input means which is not shown in figure, the video sickness tolerance evaluation apparatus 1 does not need to be provided with the still image generation means 11. FIG.

[Operation of motion sickness tolerance evaluation device]
Next, the operation of the motion sickness tolerance evaluation apparatus 1 will be described with reference to FIG. 4 (see FIG. 1 as appropriate).

First, the still image generation means 11 of the video sickness tolerance evaluation apparatus 1 has a viewing distance L from the observation position of the observer V to the screen of the display device 2 necessary for creating a still image from the implementation environment storage means 20. And implementation environment information such as the screen size of the display device 2 is acquired (step S101).
Then, the still image generation unit 11 generates a still image I having a predetermined spatial frequency component based on the implementation environment information, and stores the still image I in the still image storage unit 19 (step S102).

The movement information generation means 12 is a visual distance L from the observation position of the observer V to the screen of the display device 2 and the display device 2 necessary for generating the visible region and the movement information from the implementation environment storage means 20. Implementation environment information such as the screen size is acquired (step S103).
Then, the movement information generation unit 12 generates the visible area W and the visible area movement information including the visible area movement speed Δv and the visible area movement direction information R (step S104).

The motion video generation unit 13 acquires the still image I from the still image storage unit 19, and acquires the visible region W and the visible region movement information from the movement information generation unit 12 (step S105).
Then, the swaying image generating means 13 moves the visible region W on the still image I based on the visible region movement information, and visualizes the region of the moving visible region W (part of the still image I). A shaking image is generated (step S106).

The video display means 14 acquires the shaking video from the shaking video generation means 13 and displays the shaking video on the display device 2 (step S107).
The line-of-sight measurement means 15 acquires the eyeball image data of the observer V from the eyeball photographing device 3, and measures the rotation angle (measured visual angle value θe) of the eyeball of the observer V who is watching the motion image (step S108). .

  The mismatch degree calculation means 16 acquires visible area movement information from the video display means 14, and calculates the movement distance Ds of the visible area (step S109). Next, the inconsistency degree calculation unit 16 rotates the eyeball necessary to reach the moving destination based on the moving distance Ds of the visible region and the viewing distance L from the observation position of the observer V to the screen of the display device 2. An expected viewing angle value θs, which is an angle, is calculated (step S110).

  Then, the mismatch degree calculation unit 16 acquires the measured viewing angle value θe that is the actual eyeball rotation angle from the line-of-sight measurement unit 15, and calculates the mismatch degree ε between the measured viewing angle value θe and the expected viewing angle value θs. (Step S111).

  The motion sickness tolerance evaluation means 17 acquires the mismatch degree ε from the mismatch degree calculation means 16, calculates an evaluation value indicating the motion sickness tolerance of the observer (step S 112), and stores the evaluation value in the evaluation result storage means 18. (Step S113).

  As a result, the motion sickness tolerance evaluation apparatus 1 determines the movement amount of the motion image based on the rotation angle of the eyeball from the movement amount of the motion image and the separation distance (viewing distance L) between the observer V and the screen of the display device 2. From the expressed eyeball rotation angle (expected viewing angle value θs) necessary to reach the destination and the actual eyeball rotation angle (measured viewing angle value θe) calculated from the rotational movement of the eyeball of the observer V, The mismatch degree ε can be calculated.

  Accordingly, the motion sickness tolerance evaluation apparatus 1 generates a still image I having a constant spatial frequency according to the viewing distance L from the observation position of the observer V to the screen of the display device 2, and sets the viewing distance L to the viewing distance L. Accordingly, the moving speed of the screen (visible region W) can be changed to generate a shaking image that appears to be shaking at the same speed from the observation position of the observer V even if the viewing distance L is different. Therefore, by using the video sickness tolerance evaluation device 1, even if the screen size of the display device 2 or the viewing distance L is different, the same upset video can be displayed to the observer V regardless of the implementation environment. It becomes possible to present.

The motion sickness tolerance evaluation apparatus 1 is a viewpoint moving distance calculated from the rotation angle of the eyeball of the observer V measured by the line-of-sight measuring means 15 and the viewing distance L from the observation position of the observer V to the screen of the display device 2. Using d, a numerical value (degree of inconsistency) for evaluating the video sickness tolerance of the observer V can be calculated. Therefore, unlike the prior art, it is not necessary to measure the line of sight of the observer V based on the rotation angle of the eyeball and further calculate the coordinates of the viewpoint on the screen of the display device 2.
Further, the calculation of the inconsistency is a simple calculation that simply subtracts the expected viewing angle value θs and the measured viewing angle value θe, and therefore, a numerical value for evaluating the motion sickness tolerance of the observer V is calculated compared to the conventional case. It is possible to shorten the processing time until it is done.

The motion sickness tolerance evaluation apparatus 1 associates the evaluation value calculated by the motion sickness tolerance evaluation means 17 with the identification information of the still image I ₀ of the initial pattern that is the basis of the swaying video viewed by the observer V. By storing the result in the evaluation result storage unit 18, it becomes possible to output statistics from the evaluation values of all the viewers for each image by a predetermined statistical method by a statistical unit (not shown). This makes it possible to more comprehensively evaluate “ease of motion sickness”.
For example, the distribution of evaluation values of all observers is graphed for each still image I ₀ of the initial pattern. Accordingly, it is possible to evaluate how “an image sickness is” in view of the evaluation value of a certain observer from the whole (evaluation values of all observers). It is also possible to evaluate the observer's “easy to get sick” including the influence of the initial pattern still image I ₀ .

  In addition, the motion sickness tolerance evaluation device 1 can also evaluate the ease of causing motion sickness in the swaying image displayed on the display device 2 from the evaluation value of the observer.

(Second Embodiment)
In the first embodiment, a jumping eye movement (saccade) may occur when the observer V changes the object to be viewed instead of following the line of sight with respect to the video. Therefore, when the eye movement exceeding the eyeball rotation angle set in advance is measured by the line-of-sight measurement means 15, a jumping movement period determination means (not shown) for determining that the jumping eyeball movement has occurred is provided, and the mismatch degree calculation means 16. When calculating the degree of inconsistency ε, the degree of inconsistency from the determination that the jumping eye movement has occurred to the predetermined time set in advance is not calculated, and the degree of inconsistency ε due to the jumping eye movement is not included in the calculation. Also good.

DESCRIPTION OF SYMBOLS 1 Image sickness tolerance evaluation apparatus 2 Display apparatus 3 Eyeball imaging device 11 Still image generation means 12 Movement information generation means 13 Shaking image generation means 14 Video display means 15 Eye gaze measurement means 16 Discrepancy degree calculation means 17 Video sickness tolerance evaluation means 18 Evaluation result Storage means 19 Still image storage means 20 Implementation environment storage means

Claims (6)

An image sickness tolerance evaluation apparatus that measures an angle of rotation of an observer's eyeball that is viewing a swaying image displayed on a screen of a display device, and calculates a numerical value for evaluating the image sickness resistance of the observer. ,
Still image storage means for storing a still image of a predetermined pattern in a size larger than the screen size of the display device;
Movement information generating means for generating visible area movement information for randomly moving a visible area of the same size as the screen size of the display device on the still image;
While moving the visible region randomly on the still image based on the visible region movement information, sequentially acquiring images in the visible region, and generating a moving image generation unit,
Video display means for displaying the shaking video on the display device;
A line-of-sight measuring means for measuring a measured visual angle value indicating an angle at which the eyeball is rotated when the observer is watching the motion video;
A mismatch degree calculation means for calculating a mismatch degree between the measured viewing angle value and an expected viewing angle value representing a movement amount of the visible region as an eyeball rotation angle, as the numerical value;
A motion sickness tolerance evaluation apparatus comprising: Still image generation means for generating the still image to be stored in the still image storage means;
An implementation environment storage means for storing a viewing distance from the observer's observation position to the screen of the display device and a screen size of the display device;
The still image generating means is a size larger than the screen size of the display device, which roughens the still image of the predetermined pattern according to the viewing distance and has a constant spatial frequency component regardless of the observation position of the observer. The motion sickness tolerance evaluation apparatus according to claim 1, wherein the still image is generated. The movement information generating means
Visible region moving direction information in which the moving direction of the visible region changes randomly at a random timing within a preset range;
A visible region moving speed indicating a speed of moving the visible region, calculated from the viewing distance and a predetermined reference eye rotational relative speed obtained by randomly displacing a preset reference eyeball rotating speed within a predetermined range;
The motion sickness tolerance evaluation apparatus according to claim 2, wherein the visible area movement information including: is generated. The mismatch degree calculation means
The expected viewing angle value is calculated from the movement amount of the visible region and the viewing distance for each unit time,
A unit time mismatch degree is calculated from the difference between the measured viewing angle value and the expected viewing angle value,
Calculating the inconsistency from the sum of the unit time inconsistencies within the time when the swaying video is displayed;
further,
Video sickness tolerance evaluation means for calculating an evaluation value that the video sickness tolerance of the observer is lower as the degree of mismatch is larger,
Evaluation result storage means for storing the evaluation value;
The video sickness tolerance evaluation apparatus according to any one of claims 1 to 3, further comprising: Jumping motion determination means for determining that jumping eye movement has occurred when the measured viewing angle value measured by the line-of-sight measurement means exceeds a preset reference eyeball rotation angle value;
5. The inconsistency degree calculating unit does not calculate the unit time inconsistency until a predetermined time set in advance after it is determined by the jumping movement determining unit that a jumping eye movement has occurred. The described motion sickness tolerance evaluation device. A storage means for storing a still image of a predetermined pattern larger than the screen size of the display device, a viewing distance from the observer's observation position to the screen of the display device, and the screen size of the display device; In order to measure the angle of rotation of the eyeball of the observer who is watching the shaking image displayed on the screen of the display device with a predetermined device, to calculate a numerical value for evaluating the video sickness tolerance of the observer, The computer of the motion sickness tolerance evaluation device,
Movement information generating means for generating visible area movement information for moving a visible area of the same size as the screen size of the display device randomly on the still image;
While moving the visible region randomly on the still image based on the visible region movement information, sequentially acquiring images in the visible region, and generating a moving image generation unit,
Video display means for displaying the shaking video on the display device;
A line-of-sight measuring means for measuring a measured visual angle value indicating an angle of rotation of an eyeball when the observer is watching the shaking image, using the predetermined device;
A mismatch degree calculation means for calculating a mismatch degree between the measured viewing angle value and an expected viewing angle value representing a movement amount of the visible region by an eyeball rotation angle, as the numerical value;
Video sickness tolerance evaluation program characterized by functioning as

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