IMAGE-BASED DRIVER’S GUIDANCE SYSTEM 
Z.Tóth - T. Lovas - G. Mélyküti - Á. Barsi 
Department of Photogrammetry and Geoinformatics 
Budapest University of Technology and Economics, 
H-1111 Budapest, Müegyetem rkp. 3. 
Hungary 
{toth.zoltan, lovas.tamas,melykuti.gabor,barsi.arpad} @fmt.bme.hu 
Commission IV, WG IV/S5 
KEY WORDS: Navigation, Image database, Information system, Data structures 
ABSTRACT: 
The paper presents a low-cost navigation system, which is based on digital terrestrial images. The database of the test area is filled 
by digital images about road junctions, crossings, and other ,irregularities" taken with a high-resolution commercial camera. The 
developed guidance system solves the usual problem within urban circumstances (one or two way streets etc.), which is followed by 
a systematic image query along the found optimal path. The queried images of the database are extended by simple navigational 
instructions (arrows) to give visual information for the driver. The obtained image-based itinerary contains more information than 
the widely used navigation systems, and allows better navigation performance in unknown situations. The paper gives an overview 
about the planning of the field works, the execution of data acquisition by GPS and photography, as well as the database built-up 
and how the whole data set is structured and stored. It is followed by the presentation of the implemented algorithms. The use of the 
developed system is shown on an example executed in Budapest, Hungary. 
1. INTRODUCTION 
Due to the low-cost vehicle navigation systems, more than 5 
million navigation systems are expected to be sold in the 
European Union by 2005. These low-cost systems either 
integrate GPS receivers or are based on PDAs. 
The interfaces of this system — also called HMI (Human- 
Machine Interface) — have three main components: 
e Display interface 
e. Voice interface 
. Control interface 
The usability of the vehicle navigation system depends on the 
practicability of those components. For the users the usability is 
defined as a function as (Burnett 2000): 
e Effectiveness: achievement of user's goals, such as 
reaching a destination with no wrong turnings. 
e Efficiency: resources required by users to achieve 
those goals. 
e Satisfaction: effect on users’ opinions 
The visualization possibility of these traditional systems are 
divided into three main groups (Lovas 1999): in the first case a 
small display shows basic navigation instructions, for example 
the direction of the next turning, only as simple arrows, and 
short text messages on a small and usually monochrome LCD 
display. The VDO Dayton 4150 system uses this solution as 
shown in Figure la. The advantages of these systems are their 
low price, and simplicity. The next solution provides more 
navigation instructions for the drivers on a larger display, 
usually on a color LCD or DVD display. These systems present 
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the current position of the vehicle on a navigation map, and 
some additional information (Figure 1b). An interesting, new 
developing way is the three dimensional representation of the 
surrounding environment from bird’s eye view. This so-called 
BIRDVIEW system shows the current route emphasizing 
typical orienteering buildings (e.g. churches, bridges, towers 
etc.) (Figure 1c). 
  
  
  
  
Figure 1. The visualization solutions of the traditional 
navigation systems. 
In our solution the navigation instructions are completed with 
digital terrestrial images which were taken about the junctions 
in urban areas. The traditional navigation instructions (arrows, 
text messages etc.) extended by the terrestrial images on the 
display provide much better instruction for the drivers. In this 
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