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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B4, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
AN INNOVATION APPROACH FOR DEVELOPING A 3D MODEL BY REGISTERING A MONO IMAGE 
ON A DTM 
Amir Saced Homainejad 
Independent Research Group on Geospatial, Tehran, Islamic Republic of Iran, (saeed.homain@gmail.com) 
Commission VI, WG V1/4 
KEY WORDS: 3D model, Visualisation, Image registration, Object extraction 
ABSTRACT: 
This paper is reflecting a study on developing and reconstructing a 3D model from registering an aerial image on a point clouds or a 
DTM. The point clouds has been chosen as the main data for reconstructing a 3D model. For achieving the aspects of the study, all 
objects were individually detected and extracted from the point clouds and captured in a particular layer in a CAD environment. Then 
cach object will be converted to a raster format and will be registered on the image. This process is called the reverse registration in 
this study. Since the object segmentation and detection from a digital image is a complex process, the reverse registration is 
implemented in order to assist the process of the object detection from the image. This paper will discuss two methods of object 
detection from point clouds for the reverse registration. These methods were proposed and implemented for this study. Also, the 
paper will discuss the reverse registration and how this method improves the process of the object detection and extraction from the 
image. Discussion of reconstructing a 3D model from registering the digital image on a DTM or DSM (both of which developed 
from the point clouds data) is another goal of this paper. 
1. INTRODUCTION 
Reconstructing of 3D model from acrial images specifically, 
and in generic term from any type of images is now within the 
grasp of a vast variety of businesses. There are great benefits 
with rendering a 3D model for analysis and interpreting of the 
object, and consequently it has attracted the interest of the most 
businesses, government bodies, and developers and research 
groups. Due to implementing a reliable method for 
reconstructing a 3D model from images, a computer enhanced 
with a powerful graphic card is essential. Especially with 
development of computer graphic, the computer has been 
become easier to interact with, and better understanding and 
interpreting any type of data. Developments in computer 
graphics have had great impact in most of computer's 
applications as well as digital photogrammetry and remote 
sensing. Reconstructing a 3D model from a stereo image using a 
stereoplotter or a stereoscop is a well known technique in 
photogrammetry. In conventional fashion, a stereo model was 
reconstructed within a stereoplotter and coordinates of the 
interest points on the object or the terrain were extracted 
manually; however, in modern digital stereoplotters the process 
has been implemented automatically or it is better to say semi- 
automatically. Modern stercoplotters are able automatically to 
develop a Digital Terrain Model (DTM) or Digital Surface 
Model (DSM) from sterco images; nevertheless, there are other 
approaches for reconstruction a 3D model from non-optical 
sequence images such as those approaches has been 
implemented by Brahim et al. (2010) or Wei et al. (2009). Also 
there are some approaches for reconstruction a 3D model from 
mono image with help of the auxiliary data (Zhang and Tsui, 
1998, Qian, 2010, or Chen and Kohatsu, 2007). In recent years 
with development of computer graphics, there is an interest 
towards reconstructing 3D model in computer for visualising, 
rendering, and objects analysing. In such a context, all platforms 
for developing a 3D model have to meet the requirements of the 
3D modelling. Therefore, majority of the techniques have been 
developed based on integration of two or more sensors, while 
cach sensor provides a particular data from the terrain or the 
object and with combining those data finally a comprehensive 
3D model can be reconstructed. For example, Sportouche et al. 
(2009) reconstructed a 3D model with registering high 
resolution optical image on a SAR image. In their approach, two 
dimensional data were extracted from a mono image with 
implementing a number of constraints; they registered the 
extracted data on a SAR image. Tupin and Roux (2003) were 
developed a method that was very close to previous method. 
They also extracted planar data from images and registered on a 
SAR image. The main aspect of both methods was to detect 
buildings from SAR image which matches with their 
corresponding which already were detected from images due to 
reconstructing a 3D model. Dammann et al. (2006) 
reconstructed a 3D model by registering an optical image on a 
generated 3D model from Chirped Amplitude Modulation (AM) 
LADAR image. The purpose of registration of optical image on 
the constructed 3D model was to provide a texture to the 3D 
model. Homainejad (2011 a, 2011 b, and 2010) implemented an 
approach for reconstructing a 3D model by registering mono 
images on a generated DTM or DSM or 3D model. The 
approach consists of the following steps: 
1- Dividing the image to sub area, 
2- Each sub area was registered on its corresponding in 
the DTM or 3D model. In this step all pixel will be 
transformed to the 3D model space and will be 
converted to points. Each point included X, Y, and Z 
coordinates and intensity value which inherited from 
the image. 
3- The output from this approach is a 3D model; 
however, it has an ortho-image characteristic as well. 
This paper will discuss a new version of Homainejad's 
approach for reconstructing a 3D model by registering an image 
on a 3D model which was developed from the point clouds. The 
organisation of this paper is: the background and proposal will 
be given in the next section; study area will be given in section 
3, the methodology, the result and analysis will be given in 
section 4, and section 5 will give a conclusion. 
2. BACKGROUND AND PROPOSAL 
The author is participating in a project on urban classification 
and 3D building reconstruction which has been proposed by 
ISPRS — Commission III (Working Group III/4). The core of 
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