Journal of Heat Island Institute International Vol. 12-2 (2017)

Academic Article

Investigation and Research on the Green Visual Ratio and its
Psychological Effects Using an Omnidirectional Camera
Hirotoshi YODA

Faculty of Humanity-Oriented Science and Engineering, Kindai University
Corresponding author: yoda@fuk.kindai.ac.jp
ABSTRACTIn this study, the green visual ratio is investigated and calculated in the Iizuka urban area; the purpose is toclarify the correlations between the green visual ratio and the psychological effects.
R , the area was photographed at 69 sites, including
Using an omnidirectional camera, RICOH THETA○
schools, traffic-related facilities, other facilities, and green spaces in Iizuka City, Fukuoka Prefecture. The
photography points were neighborhood doorways as the point of contact for roadside trees and facilities. The
photographic height was set to 150 cm and the period of photography was from August 6 to August 29, 2015.
R , the green area was extracted, and the green visual ratio was calculated to divide
Using Adobe Photoshop○
the number of green pixels by the number of pixels in the circle image.
In addition, through a questionnaire to university students, the correlation between the green visual ratio andthe psychological effect was analyzed.
Key Words : Green visual ratio, Green psychological effect, Omnidirectional camera, Iizuka City

１. Introduction

manual work, based on the photograph taken at a specificviewing angle, fixing the line of sight from a certain point in the

Urban greenery has the function of improving the urban

horizontal forward direction.

thermal environment by shutting out the sunlight and changing

Conventional metrology method is highly adaptable tothe land surface. Adding to such physical effects, it has beenreality and is often used as a method of current situation

pointed out that there are psychological effects of raising

analysis.

comfort levels and calm feelings(1).

The actual view of a human being varies depending on the

In this study, the green visual ratio is investigated andsituation and behavior at each occasion. The green existence

calculated in the Iizuka urban area; the purpose is to clarify theevaluation has a great influence not only on the amount of green

correlations between the green visual ratio and the psychologicalforward in the progressing direction but also on the amount ofeffects.

overhead green. In addition, the crown looking up from underGreen coverage ratio and green visual ratio are available

the high tree and the green like the grass surface spreading out at

as an index for grasping the green amount.

the foot exist on a daily basis.

Green coverage ratio is the percentage of green covered

So it is necessary not only the measurement of thearea in a region or district. It is an index to grasp the amount of

conventional green visual rate with fixed gaze direction andplanar green, and it is used for urban planning.

viewing angle but also the measurement of omnidirectional

On the other hand, the green visual ratio is the percentage

green visual rate.

of green in the field of view.

The Iizuka City in the Fukuoka Prefecture has a total area
214.07 km2, and a population of 131,492 as of the end of June

It is a concept considered as an index close to a spatial real
feeling with respect to green coverage ratio that can be captured

2016.

in a planar view.

Natural land use consists of forest, agricultural land, andPrevious measurement of green visual ratio has beenwater, constitutes about 65% of the total of Iizuka City.

mainly a method of calculating by visual discrimination and

Unnatural land use consists of roads, residential sites,- 97 -

２. The Green Visual Ratio

commercial/office sites, industrial sites, and others.
The green quantity of land area is 14,755 ha, or
approximately 69% of the total of Iizuka City as of the end of

R 1),
Using an omnidirectional camera, RICOH THETA○

March 2008. The green area ratio of agricultural land is 18.8%,

the area was photographed at 69 sites, including schools,

the forest is 72.0%, river, reservoir, and waterways are 3.4%,

traffic-related facilities, other facilities, and green spaces infacilities’ green tracts of land such as urban parks are 1.7%, andIizuka City. The photography points were neighborhood

the golf course is 4.1% (2).

doorways as the point of contact for roadside trees and facilities.

The land use map of Iizuka City is shown in Figure 1.

The photographic height was set to 150 cm and the period ofphotography was from August 6 to August 29, 2015.
Figure 2 shows the site of view by the satellite image.
Figure 3 shows the procedures from photographing to extractingof greenery. The summary of the investigation on the green
visual ratio is shown in Table 1.
The photographed equidistant cylindrical projection image
was converted to the stereographic projection image by the
R . This stereographic
application software of RICOH THETA○

projection image can be transferred to a smartphone for viewing.
Further, the transferred still image on the touch panel can be
pinched in/pinched out, can be rotated by sliding it, can be freely
moved and can be seen with favorite angle.
The stereographic projection image was converted to theorthograpic projection image by SPCONV ver.0.7, projection
converter 3).
R ’s
The green area was roughly extracted by Photoshop○“ automatic selectiontool”, and then extracted
by visual interpretation.
The green visual ratio
was calculated to divide
Source;The land use by the Digital National Land Information in Japan, FY 2006

Figure 1. Land use map of Iizuka City

the number of green
pixels by the number ofpixelsinthecircleimage.
Source; Google Earth, 2014/10/17

Figure 2. Site of view by the satellite image(e.g. Aeon Honami Shopping Center)(a) Equidistant cylindrical projection image(b) Stereographic projection image(c) Orthograpic projection image(d) Extracted image of greenery

Figure 3. Procedures from photographing to extracting of greenery (e.g. Aeon Honami Shopping Center)- 98 -

Table 1. Summary of the investigation on the green visual ratio
Investigation enforcement days
from August 6 to August 29, 2015
69 photography sites
1. Futase District
Igisu Elementary School, Futase Junior High School, Kyushu Institute of Technology, Futase Community Center,
Kawazu Green Way
2. Kobukuro District
Kobukuro Community Center
3. Chinzei District
Yakiyama Elementary School, Kaho High School, Chinzei Community Center
4. Komoda District
Komoda Elementary School, Kyushu Junior College of Kindai University, Komoda Community Center, Iizuka Station
5. Tateiwa District
Tateiwa Elementary School, Iizuka Nisshinkan Elementary/Junior High School, Kahohigashi High School, Iizuka HighSchool, Iizuka City Hall Headquarters, Sunabilities-iizuka, Honami Welfare Research Center, Shin-iizuka Station
6. Iizuka-higashi District
Iizuka-higashi Community Center, Iizuka-daini Junior High School, Faculty of Humanity-oriented Science andEngineering, Kindai University, Iizuka-higashi Community Center, Kamimio Station, Kayanomori Greenery
7. Iizuka District
Iizuka Elementary School, Katashima Elementary School, Chuo Community Center, Iizuka Library, Iizuka Gymnasium,
Aso Iizuka Hospital, Iizuka Bus Center, Iizuka Green Way, Katsumori Park
8. Namazuta District
Namazuta Community Center, Urata Station, Namazuta Station
9. Honami District
Takata Elementary School, Rakuichi Elementary School, Iizuka City Hall Honami Branch, Honami Community Center,
Honami Gymnasium, Honami Library, Iizuka City Hospital, Saiseikai Iizuka Kaho Hospital, Aeon Honami Shopping
Center, Tento Station
10. Chikuho District
Daibu Elementary School, Iizuka City Hall Chikuho Branch, Chikuho Community Center, Chikuho Gymnasium,
Chikuho Library, Chikuho Health and Welfare Research Center, Chikuzen-daibu Station, Kuroubaru Station,
Chikuzen-uchino Station, Kami-honami Station
11. Shonai District
Shonai Elementary School, Iizuka City Hall Shonai Branch, Shonai Library, Shonai Community Center, Shonai
Gymnasium, Shonai Health and Welfare Research Center, Chikuzen-syonai Station, Chikuho Greenery
12. Kaita District
Kaita Community Center, Kaita Library, Kaita Elementary/Junior High School, Iizuka City Hall Kaita Branch, Kaita
Gymnasium, Kaita Hospital
13. Other District
Kaho-Sogo High School, Keisen Station
The green visual ratio of the investigation sites are shownat 11.8% (in Figure 5).

in Figure 4. The average total was 8.8%. Forty-seven sites

In addition, by looking at the green visual ratio of(68.1%) had less than a 10% green visual ratio, eighteen sites

facilities, it was found that the largest average score of green(26.1%) had a 10–20% ratio, one site (1.4%) had a 20–30% ratio,

spaces was 18.4%.

and three sites (4.3%) had a ratio over 30%.

The average score of public facilities was the smallest at

By looking at the green visual ratio of districts, the

7.1%, followed by education facilities and other ones at 8.5% (inaverage score at Namazuta District was the largest at 17.3%,

Figure 6).

followed by Futase District at 14.0%, and Iizuka-higashi District
Green visual ratio
40.0%
30.0%
20.0%
10.0%

Ave. 8.8%

0.0%
Education facilities (n=22)
Traffic-related facilities (n=13)

Public facilities (n=25)
Green spaces (n=5)

Figure 4. Green visual ratio at 69 photography sites (ascending order)- 99 -

Other facilities (n=4)

Maximum3/4 quartile
Average
Median
1/4 quartile
Minimum

Total (n=69)

Green spaces (n=5)

Traffic-related
facilities (n=13)

Other facilities (n=4)

Figure 5. Green visual ratio of districts

Public facilities (n=25)

Educational facilities(n=22)

Total(n=69)

Kaita(n=4)

Others(n=2)

Shonai(n=7)

Honami(n=9)

0.0%Chikuho(n=8)

0.0%Namazuta(n=3)

10.0%
Iizuka(n=9)

10.0%Tateiwa(n=8)

20.0%

Iizuka-higashi(n=6)

20.0%

Komoda(n=4)

30.0%

Chinzei(n=3)

30.0%Futase(n=5)

Green visual ratio
40.0%

Kobukuro(n=1)

Green visual ratio
40.0%

Figure 6. Green visual ratio of facilities

３. The Correlation between the Green Visual Ratio
and the Psychological Effect

The questionnaire, involving 85 university students, wascarried out on January 18 and 22, 2015.
The questionnaire contents included gender, hometown,

In addition, through a questionnaire to university students,

amount of greenery in hometown, amount of greenery in Iizuka

the correlation between the green visual ratio and theCity compared with hometown, feelings about greenery, andpsychological effect was analyzed.

impressions of greenery (in Table 2).

Table 2. Summary of the questionnaire about the green visual ratio and the psychological effectInvestigation enforcement days
January 18 and 22, 2015
84 students, 1st grade, Department of Architecture and Design, Faculty of
Execution object of the questionnaire
Humanity-Oriented Science and Engineering, Kindai University
Execution sites of the questionnaire
20 sites
The stereographic projection image have installed to a smartphone for viewing can be
How to show images to subjects
seen with favorite angle.
Questionnaire contents
1. Gender
Are you male or female?
Male/Female
2. Hometown
Where is your hometown?
□Prefecture □City
3. Amount of greenery in hometown (five-grade relative estimation), a little (-) ↔ much (+)
How much greenery is your hometown?
A little/Rather little/Neutral/Rather much/Much
4. Amount of greenery in Iizuka City compared with hometown (five-grade relative estimation) , a little (-) ↔ much (+)
How much greenery is Iizuka City compared with your hometown?
A little/Rather little/Neutral/Rather much/Much
5. Feelings about greenery (five-grade relative estimation) , dislike (-) ↔ like (+)
How about your feelings about greenery?
Dislike/Rather dislike/Neutral/Rather like/Like
6. Impressions of greenery (five-grade relative estimation)
How do you feel by looking at the image?
1) narrow (-) ↔ extensive (+) ; Very narrow (-2)/Quite narrow (-1)/Neither (±0)/Quite extensive (+1)/Very extensive (+2)2) deserted (-) ↔ lively (+) ; Very deserted (-2)/Quite deserted (-1)/Neither (±0)/Quite lively (+1)/Very lively (+2)3) dreary (-) ↔ charming (+) ; Very dreary (-2)/Quite dreary (-1)/Neither (±0)/Quite charming (+1)/Very charming (+2)4) thorny (-) ↔ friendly (+) ; Very thorny (-2)/Quite thorny (-1)/Neither (±0)/Quite friendly (+1)/Very friendly (+2)5) unpleasant (-) ↔ comfortable (+) ;Very unpleasant (-2)/Quite unpleasant (-1)/Neither (±0)/Quite comfortable (+1)/Very comfortable (+2)6) boring (-) ↔ attractive (+) ; Very boring (-2)/Quite boring (-1)/Neither (±0)/Quite attractive (+1)/Very attractive (+2)7) cold (-) ↔ warm (+) ; Very cold (-2)/Quite cold (-1)/Neither (±0)/Quite warm (+1)/Very warm (+2)8) messy (-) ↔ refreshing (+) ; Very messy (-2)/Quite messy (-1)/Neither (±0)/Quite refreshing (+1)/Very refreshing (+2)9) uncomfortable (-) ↔ comfortable (+) ;Very uncomfortable (-2)/Quite uncomfortable (-1)/Neither (±0)/Quite comfortable (+1)/Very comfortable (+2)10) undesirable (-) ↔ desirable (+) ;Very undesirable (-2)/Quite undesirable (-1)/Neither (±0)/Quite desirable (+1)/Very desirable (+2)11) poor greenery (-) ↔ rich greenery (+) ;Very poor greenery (-2)/Quite poor greenery (-1)/Neither (±0)/Quite rich greenery (+1)/Very rich greenery (+2)- 100 -

To get an evaluation in the form that is almost sight, theTable 5).

stereographic images were used in the questionnaire. The

Therefore, with regard to feelings about greenery, 75.9%

execution sites of the questionnaire, and the comparison betweenof all students responded that they felt either “like” or “rather

the green visual ratio by stereographic image and bylike”, and only one student expressed a “rather dislike”. Thisorthographic image is shown in Table 3.

shows that many have a feeling friendly to greenery (in Table 6).

With regard to amount of greenery in hometown, 47.6%

The result of a chi-square test assuming a level ofof all students responded that they felt as either “much” orsignificance of 5%, did not show any meaningful difference“rather much”. And 15.5% of all students responded that they

between gender, hometown, amount of greenery in hometown,

felt as either “a little” or “rather little”.

amount of greenery in Iizuka City compared with hometown, orWith regard to amount of greenery in Iizuka City

feelings about greenery; only the amount of greenery in thecompared with hometown, 58.4% of all students responded that

hometown and the amount of greenery in Iizuka City compared

they felt as either “much” or “rather much”. And 19.0% of allwith hometown showed a significant correlation (in Table 4 tostudents responded that they felt as either “a little” or “rather

Table 9).

little” (in Table 4).

As the amount of greenery in the hometown increases, theWith regard to both amount of greenery in hometown andamount of greenery in Iizuka City compared with hometown, theamount of greenery in Iizuka City compared with hometown
tends to be lower (in Table 7).

students felt as “much” or “rather much” are high percentage (inTable 3. Execution sites of the questionnaire, and the green visual ratio by stereographic projection image and by orthographic
projection image
Green visual ratio
by stereographic
by orthographic
projection image
projection image
26.6%
10.3%
47.5%
35.5%
12.1%
6.2%
6.7%
5.5%
2.0%
1.3%
1.7%
2.0%

Sites

Districts

Facilities

Kyushu Institute of Technology
Kawazu Green Way
Kyushu Junior College of Kindai University
Iizuka Station
Iizuka City Hall Headquarters
Shin-iizuka Station
Faculty of Humanity-oriented Science andEngineering, Kindai University
Kayanomori Greenery
Iizuka Green Way
Katsumori Park
Urata Station
Namazuta Station
Iizuka City Hall Honami Branch
Tento Station
Iizuka City Hall Chikuho Branch
Chikuzen-daibu Station
Iizuka City Hall Shonai Branch
Chikuho Greenery
Iizuka City Hall Kaita Branch
Keisen Station

FutaseFutaseKomodaKomodaTateiwa
Tateiwa

Educational facility
Green space
Educational facility
Traffic-related facility
Public facility
Traffic-related facility

Iizuka-higashi

Educational facility

14.7%

7.3%

Iizuka-higashi
IizukaIizukaNamazuta
Namazuta
HonamiHonami
ChikuhoChikuho
ShonaiShonai
Kaita
Other

Green space
Green space
Green space
Traffic-related facility
Traffic-related facility
Public facility
Traffic-related facility
Public facility
Traffic-related facility
Public facility
Green space
Public facility
Traffic-related facility

19.0%
31.9%
31.2%
33.0%
12.0%
3.7%
4.9%
8.3%
6.8%
14.3%
13.0%
1.8%
0.8%

9.6%
24.1%
10.2%
38.5%
9.8%
2.4%
2.2%
4.9%
3.6%
6.9%
12.7%
1.6%
0.8%

Table 4. Cross tabulation of questionnaire contents, gender and amount of greenery in hometown, a chi-square test (α=5%)Gender

Male
Femal
Total

Amount of Greenery in Hometown
a little (-) ↔ much (+)
-2
-1
±0
4
7
20
6.5%
11.3%
32.3%
0
2
11
0.0%
9.1%
50.0%
4
9
31
4.8%
10.7%
36.9%

- 101 -

+1
17
27.4%
7
31.8%
24
28.6%

+2

Total
14
62
22.6%
100%
2
22
9.1%
100%
16
84
19.0%
100%
 no significant differences

Table 5. Cross tabulation of questionnaire contents, gender and amount of greenery in Iizuka City compared with hometown, aGenderchi-square test (α=5%)
Amount of Greenery in Iizuka City compared with Hometown
a little (-) ↔ much (+)
-2
-1
±0
+1
Male
5
8
13
16
8.1%
12.9%
21.0%
25.8%
Female
2
1
6
8
9.1%
4.5%
27.3%
36.4%
Total
7
9
19
24
8.3%
10.7%
22.6%
28.6%

+2

Total
20
62
32.3%
100%
5
22
22.7%
100%
25
84
29.8%
100%
 no significant differences

Table 6. Cross tabulation of questionnaire contents, gender and feelings about greenery, a chi-square test (α=5%)
Feelings about Greenery-2
GenderMale
Female
Total

0
0.0%
0
0.0%
0
0.0%

dislike (-) ↔ like (+)
±0
0
16
0.0%
26.2%
1
3
4.5%
13.6%
1
19
1.2%
22.9%

-1

+1
24
39.3%
8
36.4%
32
38.6%

+2

Total
21
61
34.4%
100%
10
22
45.5%
100%
31
83
37.3%
100%
 no significant differences

Table 7. Cross tabulation of questionnaire contents, amount of greenery in Iizuka City compared with hometown and amount ofa little (-) ↔ much (+)

Amount of greenery in Iizuka
City compared with hometown

greenery in hometown, a chi-square test (α=5%)
Amount of greenery in hometown
a little (-) ↔ much (+)
-2
-1
±0
-2
1
0
1
14.3%
0.0%
14.3%
-1
0
0
3
0.0%
0.0%
33.3%
±0
0
0
8
0.0%
0.0%
42.1%
+1
2
6
6
8.3%
25.0%
25.0%
+2
1
3
13
4.0%
12.0%
52.0%
Total
4
9
31
4.8%
10.7%
36.9%

+1
1
14.3%
2
22.2%
9
47.4%
7
29.2%
5
20.0%
24
28.6%

+2

Total
4
7
57.1%
100%
4
9
44.4%
100%
2
19
10.5%
100%
3
24
12.5%
100%
3
25
12.0%
100%
16
84
19.0%
100%
 significant differences

greenerya little (-) ↔ much (+)

Amount ofhometown

Table 8. Cross tabulation of questionnaire contents, amount of greenery in hometown and feelings to greenery, a chi-square test (α=5%)
Feelings to greenery
dislike (-) ↔ like (+)
-2
-1
±0
+1
+2
Total
-2
0
0
0
3
1
4
0.0%
0.0%
0.0%
75.0%
25.0%
100%
-1
0
0
5
3
1
9
0.0%
0.0%
55.6%
33.3%
11.1%
100%
±0
0
1
4
13
13
31
0.0%
3.2%
12.9%
41.9%
41.9%
100%
+1
0
0
6
11
7
24
0.0%
0.0%
25.0%
45.8%
29.2%
100%
+2
0
0
4
2
9
15
0.0%
0.0%
26.7%
13.3%
60.0%
100%
Total
0
1
19
32
31
83
0.0%
1.2%
22.9%
38.6%
37.3%
100%
 no significant differencesin- 102 -

Table 9. Cross tabulation of questionnaire contents, amount of greenery in Iizuka City compared with hometown and feelings togreenery, a chi-square test (α=5%)
Feelings to greenery-2
a little (-) ↔ much (+)

Amount of greenery in Iizuka
City compared with hometown

-2
-1
±0
+1
+2
Total

-1
0
0.0%
0
0.0%
0
0.0%
0
0.0%
0
0.0%
0
0.0%

dislike (-) ↔ like (+)
±0
0
2
0.0%
28.6%
0
2
0.0%
22.2%
1
1
5.3%
5.3%
0
7
0.0%
29.2%
0
7
0.0%
29.2%
1
19
1.2%
22.9%

The correlation of the green visual ratio and the averagescore of impressions of greenery is shown in Table 10.

+1

+2

0
0.0%
2
22.2%
10
52.6%
12
50.0%
8
33.3%
32
38.6%

Total
5
7
71.4%
100%
5
9
55.6%
100%
7
19
36.8%
100%
5
24
20.8%
100%
9
24
37.5%
100%
31
83
37.3%
100%
 no significant differences

There was a correlation between the green visual ratio andthe impression about green amount, and it was felt that there was

Figure 7 shows the correlation between the 20 sites’ green

rich green, if over 15.5% green visual ratio in this study. The
items of “messy (-) ↔ refreshing (+),” “uncomfortable (-) ↔

visual ratio and the score on impressions of greenery.
The “narrow (−) ↔ extensive (+)” and the other six items

comfortable (+),” “undesirable (-) ↔ desirable (+),” and “poorgreenery (-) ↔ rich greenery (+)” correlated with the green

showed a plus average score for 84 student respondents.
The opposite to the “deserted (−) ↔ lively (+)” and thevisual ratio in a statistically significant level of 5% or 1%, butother three items was a minus average score for the same 84

the other items did not. It is inferred that this is due to thestudents.

influence of other factors such as green type, green position,

The items of “poor greenery (−) ↔ rich greenery (+),”“uncomfortable (−) ↔ comfortable (+),” “messy (−) ↔

green condition, green maintenance situation, non-green
structure shown in the image.

refreshing (+),” “undesirable (−) ↔ desirable (+),” “thorny (−)↔ friendly (+),” “cold (−) ↔ warm (+),” “boring (−) ↔

Figure 8 shows the average score of impressions ofgreenery of facilities.

attractive (+),” “dreary (−) ↔ charming (+),” and “unpleasant(−) ↔ comfortable (+)” showed positive correlations.

The facilities with the higher average green visual ratio
are biased toward “rich greenery”. Average green visual ratio ofMoreover, the items of “narrow (−) ↔ extensive (+)” andeducational facilities is 17.8%, next to the green spaces, but the“deserted (−) ↔ lively (+)” showed negative correlations.

score on impressions of greenery of educational facilities are

The items of “poor greenery (−) ↔ rich greenery (+)” andbiased toward “deserted”, “dreary”, and “boring”. Not only the“uncomfortable (−) ↔ comfortable (+)” showed high positive

green visual ratio of the facilities but also the surroundings

correlations.

affects the impressions of greenery.

Table 10. Correlation of green visual ratio and average score of impressions of greenery
Coefficient of
Items
Average score
determination
narrow (-) ↔ extensive (+)+ 0.480.034
deserted (-) ↔ lively (+)- 0.100.018
dreary (-) ↔ charming (+)- 0.030.022
thorny (-) ↔ friendly (+)+ 0.160.095
unpleasant (-) ↔ comfortable (+)+ 0.220.005
boring (-) ↔ attractive (+)- 0.100.038
cold (-) ↔ warm (+)+ 0.090.077
messy (-) ↔ refreshing (+)+ 0.250.293 **
uncomfortable (-) ↔ comfortable (+)+ 0.110.450 **
undesirable (-) ↔ desirable (+)+ 0.120.207 *
poor greenery (-) ↔ rich greenery (+)- 0.070.657 **
Note; ** Correlated in a statistically significant level of 1%* Correlated in a statistically significant level of 5%- 103 -

Green visual ratio withimpression score of greenery of ±0
17.0%
14.4%
14.8%
12.9%
13.4%
15.2%
14.0%
8.7%
11.6%
12.9%
15.5%

Green visual ratio

Green visual ratio
Ave. +0.48

50.0%Green visual ratio

Ave. -0.10

50.0%

40.0%

40.0%

40.0%

30.0%

30.0%

30.0%

20.0%

20.0%

y = -0.0489x + 0.1695
R² = 0.042
Ave. 14.6%

10.0%

y = -0.0227x + 0.1437
R² = 0.012
Ave. 14.6%

10.0%

0.0%

20.0%

±0

-1

+1

y = 0.0478x + 0.1477
R² = 0.035
Ave. 14.6%

10.0%

0.0%
-2

Ave. -0.03

50.0%

0.0%

+2

-2

±0

-1

+1

+2

-2

±0

-1

+1

(a) narrow (-) ↔ extensive (+)(b) deserted (-) ↔ lively (+)(c) dreary (-) ↔ charming (+)

Green visual ratio

Green visual ratio

Green visual ratio

Ave. +0.16

50.0%

Ave. +0.22

50.0%
40.0%

40.0%

30.0%

30.0%

30.0%

20.0%

y = 0.104x + 0.1293
R² = 0.098
Ave. 14.6%

10.0%

20.0%

Ave. 14.6%

y = 0.0571x + 0.1336
R² = 0.026

±0

-1

+1

Ave. 14.6%

10.0%

0.0%
-2

y = 0.0579x + 0.1517
R² = 0.041

20.0%

10.0%

0.0%

Ave. -0.10

50.0%

40.0%

0.0%

+2

-2

±0

-1

+1

+2

-2

±0

-1

+1

(d) thorny (-) ↔ friendly (+)(e) unpleasant (-) ↔ comfortable (+)(f) boring (-) ↔ attractive (+)

Green visual ratio

Green visual ratio

Green visual ratio

Ave. +0.09

50.0%

+2

Ave. +0.25

50.0%

+2

Ave. +0.11

50.0%

Kawazu Green Way

40.0%

40.0%

40.0% y = 0.2626x + 0.1164

30.0%

30.0%

30.0%

R² = 0.500

20.0%

y = 0.0694x + 0.14
R² = 0.076
Ave. 14.6%

y = 0.2417x + 0.0868
R² = 0.329

20.0%

10.0%

20.0%

Ave. 14.6%

10.0%

10.0%

0.0%

0.0%
-2

±0

-1

+1

+2

0.0%
-2

±0

-1

+1

(g) cold (-) ↔ warm (+)(h) messy (-) ↔ refreshing (+)

Green visual ratio

Green visual ratio

Ave. +0.12

50.0%

40.0%

30.0%

30.0%

y = 0.1386x + 0.1288
20.0% R² = 0.200
Ave. 14.6%

20.0%

10.0%

10.0%

0.0%

+2

Kawazu Green Way
Urata Stationy = 0.1288x + 0.1554
R² = 0.834
Ave. 14.6%

0.0%
-2

-1

±0

+1

(j) undesirable (-) ↔ desirable (+)

+2

-2

-1

±0

+1

+2

(k) poor greenery (-) ↔ rich greenery (+)

Figure 7. Correlation between 20 sites’ green visual ratio and score of impressions of greenery- 104 -

-2

-1

±0

+1

+2

(i) uncomfortable (-) ↔ comfortable (+)

Ave. -0.07

50.0%

40.0%

Ave. 14.6%

Kyushu Institute ofTechnology

-1

±0

+1
extensive (+)
lively (+)
charming (+)
friendly (+)
comfortable (+)
attractive (+)
warm (+)
refreshing (+)
comfortable (+)
desirable (+)
rich greenery (+)

narrow (-)
deserted (-)
dreary (-)
thorny (-)
unpleasant (-)
boring (-)
cold (-)
messy (-)
uncomfortable (-)
undesirable (-)
poor greenery (-)
Educational facilities (n=3)
Traffic-related facilities (n=7)
Total (n=20)

Table 12. Average green visual ratio of facilities
Facilities
Educational facilities
Public facilities
Traffic-related facilities
Green spaces
Total

Average green
visual ratio
17.8%
6.0%
9.4%
28.5%
14.6%

Public facilities (n=5)
Green spaces (n=5)

Figure 8. Average score of impressions of greenery of facilities
４. Conclusion

Notes
(8)
R
1) RICOH THETA○

In this study, the green visual ratio is investigated andTable 11. Main specifications of the device

calculated in the Iizuka urban area; the purpose is to clarify the

Shooting distancecorrelations between the green visual ratio and the psychological

Shooting mode

effects.

Exposure control mode
Exposure compensation

The average total green visual ratio of the investigation

ISO sensitivity (standard
output sensitivity)
White balance modesites was 8.8%. By looking at the green visual ratio of districts,
the average score at Namazuta District was the largest at 17.3%.
And by looking at the green visual ratio of facilities, the averagescore of green spaces was the largest at 18.4%.
The result of a chi-square test assuming a level of

Shutter speed

significance of 5%, the amount of greenery in the hometown andMemoryStorage capacity

the amount of greenery in Iizuka City compared with hometown
showed a significant correlation.
Shown as the correlation of the green visual ratio and thePower
Battery life
Image file format

average score of impressions of greenery, the items of “poorgreenery (−) ↔ rich greenery (+)” and “uncomfortable (−) ↔
comfortable (+)” showed high positive correlations.

External interface
Dimensions (L x W x D)
WeightOperating temperatures
Operating humidity
Storage temperatures

There was a correlation between the green visual ratio andthe impression about green amount, and it was felt that there wasrich green, if over 15.5% green visual ratio in this study. The
items of “messy (-) ↔ refreshing (+),” “uncomfortable (-) ↔

Approximately 10cm to infinity(from front of lens)Still image: Auto, shutter priority, ISOpriority *5, Video: Auto
Automatic
Still image: Manual compensation(-2.0 - +2.0EV, 1/3EV step)
Still image: ISO 100 to 1600, Video: ISO
100 to 400
Still image: Auto, indoors, outdoors,
cloudy, incandescent lamp 1, incandescentlamp 2, daylight color fluorescent lamp,
natural white fluorescent lamp, whitefluorescent lamp, light bulb color
fluorescent lamp*5, Video: Auto
Still image:1/8000 to 1/7.5 secont,Video:1/8000 to 1/15 secont
Internal, approximately 4GB
Still image: Approx. 1200, Video (timeper recording): Max. 3 minutes, Video(total recording time): Approx. 40
minutes.
Internal lithium ion battery
Approximately 200 captures
Still image: JPEG (Exif Ver. 2.3), DCF2.0
compliant, MOV (Video: MPEG-4
AVC/H.264, Audio: LinearPCM)
microUSB2.042mm x 129mm x 22.8mm (17.4mm)
Approx. 95g
0 to 40℃
Under 90%
-20℃ to 60℃

comfortable (+),” “undesirable (-) ↔ desirable (+),” and “poorgreenery (-) ↔ rich greenery (+)” correlated with the green
visual ratio in a statistically significant level of 5% or 1%, but
the other items did not. It is inferred that this is due to the
influence of other factors such as green type, green position,
green condition, green maintenance situation, non-green
structure shown in the image.
We will continue our research in the future and clarify therelevance between items other than green visual ratio andFigure 9. Photograph of the device

impressions of greenery.

- 105 -

Acknowledgements
The author would like to express thanks to Mr. Kanamaru
and the Iizuka City Planning Division.
References(1) Green Tract of Land Environment Promotion Room, MLIT,
About the Urban Green Scene and Psychology Effect ofRelaxing the Discomfort of the Hot Day, the Social Experiment
Investigation into Correlation of the Urban Green Quantity andthePsychological

Effect

of

the

City,

(2005),

http://www.mlit.go.jp/kisha/kisha05/04/040812_3_.html.
(2) Iizuka City, Iizuka Greenery Basic Plan (2010).
(3) A, Nagata, SPCONV ver.0.7,projection converter, Building
Simulation Resources Library, Application and Database by the
AIJ Thermal Environmental Simulation Subcommittee, (2015),
http://news-sv.aij.or.jp/kankyo/s12/Resource/ap/SPCONV/SPC
ONV.htm.
(4) A. Nakagawa et al., Selection of Greening Maintenance
Promotion Area by Green Rate and Estimation of Impression in
the Central District of Oita City (Part 2), Summaries ofTechnical Papers of Annual Meeting, AIJ, F-1, (2008),
pp.1119-1120.
(5) Osaka Prefecture, Green Visual Ratio Investigation Guideline(2013).
(6) T. Takahashi et al., Study on the Evaluation of Green Landscapeon the Street Researched form the Aspect of the Ratio of Greenin Photograph and Green Rate, Summaries of Technical Papersof Tokai Branch, AIJ, 45, (2007), pp.541-544.
(7) T. Fujii et al., Measurement of the Ratio of Visible Green Spacesin the Omnidirectional Field of Visual using CG Models andtheir Potential Applications, AIJ Journal of Technology and
Design Vol. 19, No. 43, (2013), pp.1067-1072.
(8) RICOH IMAGING COMPANY, LTD., RICOH THETA,
http://www.ricoh-imaging.co.jp/english/products/theta_m15/.
(Received Apr. 25, 2017, Accepted Jul. 7, 2017)- 106 -