24 Depth scaling of binocular stereopsis by observer s own movements 1130313 2013 3 1
3D 3D 3D 2 2 i
Abstract Depth scaling of binocular stereopsis by observer s own movements It will become more usual for observers to move while observing 3D images as virtual reality and 3D games prevail. The stereoscopic 3D perception is achieved by presenting images with binocular disparity and the binocular disparity changes depending on the viewing distance. So even if we see the same object, the retinal disparity changes according to the viewing distance. Although the previous study investigated depth scaling when the target object is moved in the direction of depth, how we perceive and scale depth when we actively move is largely unknown. Thus, the purpose of this study is to investigate the characteristics of the scaling of depth by the movement of the observer and examined the disparity value which the depth of object seem to be the same between two viewing positions by presenting static frames of stereograms in each position. In addition, to examine the effect of a continuous change of disparity in real time during the observers movement, we set the condition which showed the object continuously and dynamic change of disparity are presented. The results showed that the depth seemed to be constant when the disparity of object is smaller than theoretical value in shorter distance, i.e. the flatter object seemed to be the same if observer moved close to the object in both static two frames condition and real-time continuous displaying condition. These results might come from the underestimation of the movement distance, or increase of binocular disparity itself because of the shorter ii
viewing distance. As correlation analysis between perceived movement and perceived depth revealed no correlation among them, it is plausible that the result may be caused by the increase of disparity. The clear difference between two frame and continuous conditions was not found and this result suggests that the continuous and gradual change of disparity does not have a significant effect on accurate depth scaling. key words Binocular disparity, viewing distance, depth, movement, random dot stereogram iii
1 1 1.1...................................... 1 1.2................................... 2 1.3................................ 4 1.4................................... 4 2 5 2.1...................................... 5 2.2...................................... 7 2.3.................................... 9 2.4.................................... 10 2.4.1 12....................... 10 2.4.2 2........................ 12 3 14 3.1 12.......................... 14 3.2 2........................... 20 3.3................... 27 4 28 5 29 30 31 iv
1.1 [2].................................. 2 1.2 [3].......................... 3 2.1................................. 6 2.2................................... 6 2.3................................... 6 2.4..................................... 6 2.5.......................... 8 2.6.............................. 8 2.7...................................... 8 2.8 1................................ 11 2.9 2................................ 13 3.1 1................................. 14 3.2 A 1........................... 15 3.3 B 1........................... 15 3.4 C 1........................... 16 3.5 D 1........................... 16 3.6 E 1........................... 17 3.7 F 1........................... 17 3.8 G 1........................... 18 3.9 2................................. 20 3.10 A 2........................... 21 3.11 B 2........................... 21 v
3.12 C 2........................... 23 3.13 D 2........................... 23 3.14 E 2........................... 24 3.15 F 2........................... 24 3.16 G 2........................... 25 3.17................... 27 vi
1 1.1 3D 3D 3D 3D 3D 3D 3D [1] 1
1.2 1.2 1.1 [2] 6 cm 2
1.2 1.2 [3] 1.2 F 1 F 2 2 a 6 cm F 1 DF 1 F 2 D 1.2 F 1 F 2 θ 1 θ 2 θ 1 θ 2 θ θ = θ 1 θ 2 = α 2 α 1 a D a D a D D 2 = 206, 265 a D D 2 D 2 [4] 3
1.3 1.3 6 12 18 4 4 m [5] 1.4 2 2 2 4
2 2.1 6 cm 12 cm 90 cm 3.82 deg 7.63 deg 60 cm 5.72 deg 11.42 2.4 cd/m 2 76.7 cd/m 2 2000 90 cm 3 cm 60 cm 1.5,2 2.5 3 3.5 4 4.5 cm 90 cm 0.13 deg 60 cm 0.140190.240.290.33 0.380.43 deg 2.2 2.3 2 1 1.125cm 1.125 cm 5
2.1 2.1 2.2 2.3 2.4 6
2.2 2.2 MATLAB+Psychtoolbox 21 CRT EIZO FlexScan T9611024 768pixel 120Hz3D 3D PC ELECOMTK2-BT3H 2 POLHEMUS FASTRAK 60 Hz 150 cm 120 cm 200 cm 7
2.2 2.5 2.6 2.7 8
2.3 2.3 7 9
2.4 2.4 2.4.1 12 90 cm 3 cm 1.5s 90 cm 90 cm 60 cm 60cm 60 cm 5 60 cm 7 1.5 s 6 4 90 cm 5 1 7 10 3 210 10
2.4 2.8 1 11
2.4 2.4.2 2 CRT 90 cm 3 cm 1.5 s 1 90 cm 90 cm 1.5 s 60 cm 60cm 60 cm 60 cm 7 60 cm 1.5 s 5 6 4 90 cm 5 1 7 10 3 210 90 cm 60 cm 12
2.4 2.9 2 13
3 3.1 12 1 7 3.1 3.2 3.8 90 cm 3 cm 0.5 0.5 2.36 cm 3 cm t6= 9.156p< 0.012.36 cm 3 cm 75 cm 3.1 1 14
3.1 12 3.2 A 1 3.3 B 1 15
3.1 12 3.4 C 1 3.5 D 1 16
3.1 12 3.6 E 1 3.7 F 1 17
3.1 12 3.8 G 1 18
3.1 12 0.5 3.1 3cm 3.1 0.5 1 0.5 A B C D E F G 2.5cm 2.65cm 1.51cm 2.5cm 2.3cm 2.63cm 2.44cm 19
3.2 2 3.2 2 2 7 3.9 3.10 3.16 90 cm 3 cm 1 0.5 0.5 2.55 cm 3 cm t6= 13.254p< 0.01 2.55 cm 3 cm 69.97 cm 3.9 2 20
3.2 2 3.10 A 2 3.11 B 2 21
3.2 2 0.5 3.2 6 3cm 3.2 0.5 2 0.5 A B C D E F G 2.46cm 2.17cm 2.3cm 2.34cm 2.27cm 2.51cm 3.04cm 22
3.2 2 3.12 C 2 3.13 D 2 23
3.2 2 3.14 E 2 3.15 F 2 24
3.2 2 3.16 G 2 25
3.2 2 3.2 7 4 1 2 3.3 90cm 60cm A 100cm 60cm 40cm B 100cm 60cm 40cm C 100cm 80cm 20cm D 50cm 40cm 10cm E 110cm 80cm 30cm F 100cm 80cm 20cm G 70cm 50cm 20cm 26
3.3 3.3 1 2 3.17 27
4 1 2 2 1 2 2 0.5 1 2 2.36 cm 2 2.55 cm 2 2 t6= 0.400p= 0.702 3D 3D 3D 28
5 3D 3D 2 2 29
30
[1] PScarfePBHibbardDisparity-defined objects moving in depth do not elicit three-dimensional shape constancyvision Res200646101599-610 [2] GibsonJJ1950The perception of the visual worldhoughton Miffilin [3] Graham CHEd1965 Vision and visual perceptionwiley [4] OnoHand commerfordjstereoscopic depth constancyepstein W1977 Stability and constancy in visual perceptionwiley-interscience PublicationNew York [5] Vision132001 pp163-180 [6] 60(4)2004 pp 455-459 [7] Vol10 2005No 2 pp249-256 [8] --2000 [9] 2000 [10] Psychtoolbox http://sites.google.com/site/ptbganba/ 31