DEM generation and accuracy assessment from stereo ASTER imagery

Ok, AO
Turker, M
In this study, Digital Elevation Models (DEMs) were generated from ASTER stereo images for a study area enclosing the city of Ankara and covering an area of 3600 km(2). Majority of the area was covered by large scale orthophotos, which were used as the main source to collect the Ground Control Points (GCPs). For those areas that were not covered by the orthophotos the GCPs were collected through a differential GPS. The bundle adjustment process and the generation of DEMs were carried out using PCI Geomatica image analysis software. In order to rind the best GCP combination, DEMs were generated using different number of GCPs (8, 16, 24 and 32). DEM accuracies were assessed based on different parameters including the check points, slopes and land cover types. The accuracies of the resulting DEMS revealed that 16 GCPs were good compromise to produce the most accurate DEM. It was found that the post processing and blunder removal were crucial stages that affect the overall DEM accuracy up to 38%. There was a strong linear relationship between the accuracy of DEMS and the terrain slopes. For urban and forested areas, the accuracy in elevation was found to be 8.03 m and 12.69 m, respectively. The overall accuracy computed for 2,171,664 points produced 10.92 m elevation accuracy.


Geometric Camera Calibration of BiLSAT Small Satellite Preliminary Results
Friedrich, Jurgen; Leloğlu, Uğur Murat; Tunalı, Erol (null; 2006-02-14)
The interior geometric calibration of the multi-spectral camera of BiLSAT satellite is aimed using three sets of images from Ankara. Each set contains four different images for channels Red, Green, Blue (RGB), and Near Infra Red (NIR) in which well-defined target points were identified and their image coordinates measured. The target points’ UTM coordinates were extracted from aerial photos or topographic maps and collected from field using hand-held GPS receiver. A least square parameter estimation was the...
Digital terrain model extraction from high-resolution point clouds by using a multi-resolution planarity-based approach
Koçan, Yasin; Leloğlu, Uğur Murat; Department of Geodetic and Geographical Information Technologies (2021-9-09)
Digital Elevation Model (DEM) is a mathematical representation of the elevation of the Earth’s surface. There are two types of DEM, namely Digital Surface Model (DSM) and Digital Terrain Model (DTM). DSM contains natural (bare-ground, trees, bushes, etc.) and artificial above-ground objects (buildings, vehicles, powerlines, etc.), while DTM covers only the bare earth without anything on it. Above-ground objects need to be removed to extract the DTM, which is a tedious task. This thesis proposes an algorithm...
Discontinuity mapping with automatic lineament extraction from high resolution satellite imagery
Karpuz, Celal (null; 2004-09-01)
In this study, automatic lineament analysis is performed by using high resolution satellite imagery for identification of rock discontinuities. A case study area is selected as an Andesite mine area in Gölbaı, Ankara, Turkey. For the high resolution data 8-bit Ikonos Precision Plus with 1 meter resolution orthorectified image is used. The image data contain three bands as blue, green, red as band 1, band 2 and band 3, respectively. Then an additional band (fourth band) for the image is assigned by obtainin...
Kose, Kivanc; Yılmaz, Erdal; ÇETİN, AHMET ENİS (2009-07-17)
In this paper a new Digital Elevation Map (DEM) image compression algorithm is proposed. DEM image can be threated as a grayscale image, whose pixel values are the elevation values of the map points. The grayscale DEM image is compressed using an adaptive wavelet based image compression algorithm. The method, which is an extension of the progressive mesh compression takes advantage of the multiresolution property of the wavelets while coding the map images. This makes it possible to decode different resolut...
Ground Motion Characterization for Vertical Ground Motions in Turkey—Part 2: Vertical Ground Motion Models and the Final Logic Tree
Gülerce, Zeynep; SANDIKKAYA, MUSTAFA ABDULLAH (Springer Science and Business Media LLC, 2020-05-01)
The main objectives of this study are: (1) to choose the vertical ground motion models (GMMs) that are consistent with the magnitude, distance, depth, and site amplification scaling of the updated Turkish ground motion database, and (2) to combine the vertical GMMs with the V/H ratio models selected in the accompanying paper (Alipour et al. in Pure Appl Geophys 1-22, 2019) to provide the ground motion characterization logic tree for the vertical ground motion component in Turkey. Four global vertical GMMs [...
Citation Formats
A. Ok and M. Turker, “DEM generation and accuracy assessment from stereo ASTER imagery,” 2005, p. 523, Accessed: 00, 2020. [Online]. Available: