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Research paper : Developing an evaluation system of visually induced motion sickness for safe usage of moving images (H. Ujike)−143−Synthesiology - English edition Vol.5 No.3 (2012) image display condition, and viewer attribute, as shown in Table 1, as well as the primary factors that trigger VIMS and the secondary factors that strengthen or weaken it. According to this table, the primary factor that triggers VIMS is the visual global motion categorized as the image contents. The basis is the sensory rearrangement theory mentioned earlier, and more specifically the visual global motion that is given when the body is actually static becomes the motion information, and causes discrepancy between the sensory information from the somatic and vestibular sensory systems and thereby causes sickness.[2] Therefore, in the VIMS evaluation system, the findings from biomedical effects pertaining to the visual global motion were selected as the primary component.The basic characteristic of the biomedical effect by visual global motion was studied by the author et al. in the “Standardization of the Image Safety Evaluation Method (FY 2003~2005),” a Standardization Certification R&D Project, Ministry of Economy, Trade and Industry. The author et al. set up a virtual room by CG where the observer stood in the center of that room. The three axes (pitch, yaw, and roll axes mentioned earlier) were set with the observer’s head in the center, and the observers were shown the CG moving image in which the reciprocating rotational motion (oscillation) around each axis occurred. The size of the image was 82 deg × 67 deg, duration about 1 minute, and the observer was asked for a subjective evaluation pertaining to VIMS on a 11-point scale. Two types of amplitudes (30, 90 deg) and six types of temporal frequencies (0.03, 0.06, 0.12, 0.24, 0.49, and 1.0 Hz) were used as the conditions for the reciprocating rotational motion around each axis. As a result, as shown in Fig. 5, the effect of VIMS was dominated not by the temporal frequency of the visual global motion in the image but mainly by the velocity component.[10] Fig. 5 Effect of the visual global motion on VIMSFig. 4 Relationship of the elemental technology in the VIMS evaluation system******10Model operationUse of moving images Input dataBasic data-Psychological measurement-Physiological measurementMajor experimental resultExperimental sceneUtilize produced imageBiomedical measurement to improve the accuracy of VIMS evaluation modelEstimation of VIMS using actual imageConstruction of the model for output based on the velocity of visual global motion included in moving imageVIMS evaluation modelVisual global motion analysis of imageBasic results of biomedical effects of visual global motionVIMS basic characteristics data of VIMS obtained with basic experimentsGlobal motion estimateLocal motion estimateZoomRollPanTiltTime (min)Amount of responseSustained responseTransient responseMaximum velocity (deg/s)* p<0.05 (Mann-Whitney test)Amplitude 90 degAmplitude 30 degSubjective scores concerning VIMSPitchYaw0.00.51.01.52.02.5101001000101001000Production of image that is likely to cause sickness, based on image production methodMaximum velocity (deg/s)*********1010010000.00.51.01.52.02.5Subjective scores for VIMS* p<0.05 (Mann-Whitney test)Amplitude 90 degAmplitude 30 degPitchYawRoll101001000101001000

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