International Conference on Artificial Reality and TelexistenceEurographics Symposium on Virtual Environments (2019)
Y. Kakehi and A. Hiyama (Editor)

Poster

Virtual remote view system in traffic jam
using smartphone peer-to-peer image propagation
Shohei Miki1 , Hirotaka Itoh1 , Kenji Funahashi1
1 Nagoya Institute of Technology, Nagoya, Japan

Abstract
You usually want to know the traffic situation ahead while driving. For example, you probably want to see a situation at thehead of a traffic jam. In this study, we propose a virtual remote view system in a traffic jam. Smartphones on a dashboard areconnected as peer-to-peer communication, and the jammed road images are propagated to them behind. An experiment wasconducted to confirm that this system works properly. Some positive evaluations for a virtual remote view were obtained fromsubjects.
CCS Concepts• Information systems → Multimedia information systems;

1. Introduction

2. Concept and outline

You usually want to know the traffic situation ahead while driving. You also want to know it over the vehicle in front of you. The
see-through view system has been proposed [SH12], a road image taken at the front of a truck is displayed on a rear panel ofa compartment. The other see-through view system has been proposed too [RHJ∗ 16], a vehicle on a road image is detected and removed by using some different position camera images. They needlarge equipment and are expensive to get "remote view". We havealso proposed a deferent type see-through system [MIF18], that issmartphone application and transfers a road image to a behind vehicle smartphone. Note that some automobile manufactures use theword; see-through also for an image monitor such as a navigation
system that displays blind spot image. Our system does not needa special device or server computer, but is realized by peer-to-peer
communication.

The virtual remote view system needs (1) a function to judge
whether it is a traffic jam or not, and (2) a function to propagate
an image to behind.

Here, these systems work for nearby vehicles, and they ahead aremade transparent. On the other hand, jam information is generally
reported and displayed on a navigation system recently, you probably want to see the situation at the head of a traffic jam. Although
there is a research to provide traffic jam road images from server toclient [TOY∗ 13], it still contains a same problem of a see-throughview system. In this study, we propose a virtual remote view system
in a traffic jam. Smartphones on a dashboard are connected as peerto-peer communication, and the jammed road images are propagated to them behind. You, driver can grasp traffic condition ahead
intuitively. Of course this system does not contribute to safety directly, unlike see-through, it is expected to relive the driver’s stress,
and to improve safety.
c 2019 The Author(s)⃝c 2019 The Eurographics Association.
Eurographics Proceedings ⃝(1) Traffic jam judgement: In order to distinguish a traffic jamfrom waiting at the lights and parking, first, when driving at lessthan a predefined threshold speed V [km/h] for a threshold period
T [sec], this vehicle is judged in a candidate state of traffic jam.
If one of the following three conditions is satisfied additionally,
this vehicle is judged in a traffic jam state.
• A traveled distance is more than a threshold distanceM[meter] after the state is changed to candidate.
• The number of the vehicles that states are candidate and aretraveling for a same direction is equal to or more than N.
• The number of the vehicles that states are traffic jam and aretraveling for a same direction is equal to or more than 1.
(2) Image propagation: In order to send an image from a smartphone to another smartphone, each smartphone acts one of theroles as a head transmitter node, a relay transmitter node, and a
receiver node according to each condition.
• There is no cars ahead that states are traffic jam and directions
are same: this smartphone acts as a head transmitter node.
It sends a front view image to a receiver node behind thatrequests. For the last receiver node within a threshold distance D[meter] behind, the head transmitter node send it amessage to act a relay transmitter node.

Shohei Miki & Hirotaka Itoh & Kenji Funahashi / Virtual remote view system in traffic jam using smartphone peer-to-peer image propagation• A front image sent by a transmitter node carries a role change
message: this smartphone acts a relay transmitter node.
It works like a head transmitter node, i.e. sends an image
and a message.
• There is a head or relay transmitter node ahead: this smartphone acts a receiver node.
It sends the nearest transmitter node ahead an image request.
In other words, the system needs each smartphone position, and tocalculate each speed, direction, and traveled distance. It also needs
to communicate with other smartphones around it, and to know
their information.
Figure 2: Appearance of experiment
3. Implementation
The pilot application for virtual remote view is implemented on anAndroid device. GPS function of a smartphone is used to obtain its
position data. Speed, direction, and traveled distance are calculated
by GPS displacement. Wi-Fi Direct technology is also used to communicate with other smartphones around it. Some information of asmartphone is necessary to decide a node role before connection isestablished, so they are labeled within a broadcastable device nameaccording to the Wi-Fi Direct standard. After connected based on arule mentioned above, each smartphone send or receive a jammedroad image as a socket communication.
A driver usually want to see not only a head image of a trafficjam, but also a halfway image of it, a road image ahead taken by
not only a head transmitter node, but also a relay transmitter node
is sent behind. However long traffic jam causes a large number ofimages, images should be thinned out. The GPS position data ofimages are compared for a pair of the closest images then morebehind image is removed until a threshold number, to keep road
images at equidistant intervals. They are displayed on an application screen in a list format (Fig. 1), and are able to scroll aheadand behind and to enlarge with text information as an image taken
position something like that.

Figure 3: Application screen (No. 4) of pilot system with images ofNo. 1 and No. 3 in Figure 2
the experiment; V = 20, T = 1, M = 100, N = 2, and D = 50.
The experiment assumed the situation where cars were in a traffic
jam without any actual cars (Fig. 2). Four Android devices wereused for the test. It was confirmed that each device changed arole according to the conditions, and propagated images each other(Fig. 3); Some positive evaluations for a virtual remote view werealso obtained from subjects. In the future, thinning image methodshould be reconsidered, the images that are not appropriate to get
the lay of the land, i.e. just a large rear panel image of a truck compartment, should be thinned.

4. Result and conclusion
An experiment was conducted to confirm that this virtual remote
view system propagates images taken by a smartphone ahead properly. Following thresholds and constant are used empirically inReferences[MIF18] M IKI S., I TOH H., F UNAHASHI K.: See-through View System
Using P2P Communication on Smartphones between Vehicles LocatedTandem. In Proc. Tokai-Section Joint Conference on Electrical, Electronics, Information, and Related Engineering (in Japanese) (Sep 2018),
pp. M2–5. 1[RHJ∗ 16] R AMEAU F., H A H., J OO K., C HOI J., PARK K., K WEON
I. S.: A Real-Time Augmented Reality System to See-Through Cars.
IEEE Transactions on Visualization and Computer Graphics 22 (Nov.
2016), 2395 – 2404. 1[SH12] S UZUKI K., H ASHIMOTO N.: Visual assistance system using
shared vehicle camera images. The Institute of Image Information andTelevision Engineers Technical Report (in Japanese) 36 (Feb. 2012), 29–32. 1

Figure 1: Illustration of expected application screen[TOY∗ 13] TAMAI M., O NOUE Y., YASUMOTO K., F UKUKURA T.,
I WAI A.: An images processing-based method for efficient collection
and sharing of video data about conditions of vehicular traffic congestion. IPSJ SIG Technical Report (in Japanese) 2013-MBL-65 (Mar.
2013), 1–8. 1
c 2019 The Author(s)⃝c 2019 The Eurographics Association.
Eurographics Proceedings ⃝