Accuracy Of DEM Research Articles

Evaluación y comparación de métodos de interpolación determinísticos y probabilísticos para la generación de modelos digitales de elevación

Digital elevation models (dem) are the most common and effective representation of the land surface. Unfortunately, similarly to most digital geographic information, dem inherently contain errors, which magnitude should be assessed and informed to dem users. One factor that introduces errors in dem is the interpolation method and several previous studies have presented findings that disagree among them regarding the suitability of several interpolation methods for dem generation. With the aim of contributing to this discussion and of improving the understanding of errors introduced in dem by interpolation methods, in this paper we evaluate and compare the accuracy of dem generated using both deterministic (idw, anudem) and probabilistic (ok, kt) interpolation methods. Our results suggest that kt produces more accurate dem than the other interpolation methods evaluated in this paper and that it produces dem without systematic errors, which occur in dem generated using idw, anudem and ok. These results are consistent with some previous studies, but at the same time disagree with other similar studies.

Comparison of gross tractive effort of a single grouser in two-dimensional DEM and experiment

In the development of DEM programs for interaction studies, 2D DEM analysis is often compared to the results of experiments done in 3D conditions. From an alternative viewpoint, a quasi-2D experiment was designed for this study to collect results of gross tractive effort and to examine the accuracy of 2D DEM applied to soil–grouser systems. To intensify the understanding and comparison of the grouser reaction and soil behavior, a soil model incorporating aluminum cylinders was used in the experiment instead of real soil. The particle size distribution of model soil was approximated by the combination of cylinders of two radii. The bulk density was set to be identical in DEM and the experiment. The normal spring constant and the coefficient of rolling friction in the contact model of DEM were adjusted using trial and error, considering the allowable time step, sinkage of the grouser, and the slope angle of the cavity behind the grouser. The developed 2D DEM program was confirmed to have sufficient capability to reproduce the experimentally obtained results of gross tractive effort with nine combinations of conditions of grouser height and grouser thickness.

Fast Data Acquisition of Aerial Images Using Unmanned Aerial Vehicle System

The present work discusses the technique and methodology of analysing the potential of fast data acquisition of aerial images using unmanned aerial vehicle system. This study utilizes UAV system for large scale mapping by using digital camera attached to the UAV. UAV is developed from the low-altitude photogrammetric mapping to perform the accuracy of the aerial photography and the resolution of the image. The Ground Control Points (GCPs) and Check Points (CPs) are established using Rapid Static techniques through GPS observation for registration purpose in photogrammetric process. The GCPs is used in the photogrammetric processes to produce photogrammetric output while the CP is employed for accuracy assessment. A Pentax Optio W90 consumer digital camera is also used in image acquisition of the aerial photograph. Besides, this study also involves image processing and map production using Erdas Imagine 8.6 software. The accuracy of the orthophoto is determined using the equation of Root Mean Square Error (RMSE). The final result from orthophoto is compared to the ground survey using total station to show the different accuracy of DEM and planimetric survey. It is discovered that root mean square errors obtained from UAV system are ± 0.510, ± 0.564 and ± 0.622 for coordinate x, y and z respectively. Hence, it can be concluded that the accuracy obtained from UAV system is achieved in sub meter. In a nutshell, UAV system has potential use for large scale mapping in field of surveying and other diversified environmental applications especially for small area which has limited time and less man power.

GeoEtrim, SharpQ and Epix: Trio of Tools for Geospatial Image Analysis

Abstract. This paper presents an overview of three approaches developed in Matlab for geospatial analysis of images. GeoEtrim has two subpackages, GeoSpot and GeoFigcon. GeoSpot aims to perform bundle adjustment of stereo linear array remotely sensed images considering their interior and exterior orientation parameters. The correlation among orientation parameters, their validation and efficiency on the final accuracy can be estimated. The current version is available for SPOT-5 HRG level 1A stereoimages, reaching ±1 pixel accuracy at ICPs (Independent Check Points). GeoFigcon is the other sub-package of GeoEtrim, developed for estimation of georeferencing accuracy of orthoimages generated by various sensor-independent mathematical models and RFM (Rational Function Model). Using GeoFigcon, one can estimate the combined effect of the accuracy of transformation parameters estimated/updated by GCPs and DEM accuracy on the georeferencing accuracy of orthoimages. The experiments with IKONOS Geo, QuickBird OrthoReady Standard, OrbView-3 Basic and Pléiades-1A Primary prove that using RFM produces higher accuracy than using sensor-independent transformation models. Moreover, accuracy varies reducing from geometric centre of GCPs accommodating the high profile of topography. SharpQ generates pan-sharp images using the methods PCA (Principal Component Analysis), Brovey, and IHS (Intensity Hue Saturation), validates their quality with quantitative analysis by the methods CC (Correlation Coefficient), RMSE (Root Mean Square Error), RASE (Relative Average Spectral Error), SAM (Spectral Angle Mapper) and ERGAS (Erreur Relative Globale Adimensionnelle de Synthése). epix, the last member of the trio, can be used for estimation of effective GSD (Ground Sampling Distance) value of original or generated (such as pan-sharp) images, depending the principle of ESF (Edge Spread Function). So the real geometric resolution can be estimated for any kind of image. This trio is being still developed with the continuous research.

EVALUACIÓN DE MDE PARA LA ESTIMACIÓN DE VOLÚMENES POR PROCESOS DE EROSIÓN APLICANDO ANÁLISIS DE AUTOCORRELACIÓN ESPACIAL EN UNA CUENCA DE LOS ANDES VENEZOLANOS. CASO DE ESTUDIO: MICROCUENCA TORRENCIAL LA MACHIRÍ

La revista Colombia Forestal publica manuscritos originales en temáticas del campo forestal y diversos aspectos de los recursos naturales y del medio ambiente, los cuales se discriminan en las categorías de artículo de investigación, de revisión, de reflexión y notas técnicas de acuerdo con lo estipulado por COLCIENCIAS para las publicaciones científicas. De acuerdo a la clasificación de áreas científicas de la Organización para la Cooperación y el Desarrollo Económico (OCDE), la revista Colombia Forestal pertenece al gran área de Ciencias Agrícolas(4), área de Agricultura, Silvicultura y Pesca(4A) y a la disciplina Forestal (4A02).

A regional-scale assessment of digital mapping of soil attributes in a tropical hillslope environment

The purpose of this study was to analyze the relationships between soil attributes and environmental covariates in a tropical hillslope environment on a regional scale to estimate spatial distribution of soil attributes and identify statistical and geostatistical techniques that could represent the variation of the soil attributes. The study was performed in Bom Jardim County, Brazil, and covered an area of 390km2 with a soil database of 208 sample points distributed in six depth layers (0.53 pts/km2). The study used 18 environmental covariates derived from DEM and satellite imagery. The models evaluated were linear regression, regression trees and ordinary and regression kriging. An exploratory analysis showed that DEM, NDVI, MRVBF, MSP, b3/b2, b5/b7, SPI, SWI, SLOPE and ASPECT were correlated with soil properties. The models performance had a mean crossvalidation r2 of 0.13. The best results were achieved with kriging models, with a crossvalidation r2 of 0.19. A comparison between multiple linear regression and regression trees showed that the tree model yielded the best results. The sample density alone could not explain the results, but an interaction between DEM accuracy, sample density, covariates and geological conditions was suitable as an explanatory factor. Studies of tropical hillslope digital soil mapping on regional scales need to be more exhaustively focused to develop this research area.

Effect of DEM data resolution on low relief region sub-watershed boundaries delineating using of SWAT model and DEM derived from CARTOSAT-1 (IRS-P5), SRTM and ASTER

Watersheds are natural integrators of hydrological, biological, and geological processes and as such require an integrated approach to data analysis and modeling, which usually starts delineating accurately a polygon vector layer of watershed boundaries as input. In that way, Garrah sub-watershed in Shahjahanpur district of U.P., India, had been isolated with the objective of evaluate the accuracy of sub-watershed boundaries derived from three different sources: One was delineated by 2.6 m resolution CARTOSAT-1 DEM (IRS-P5) and other two were derived from a 30 m ASTER DEM and a 90 m SRTM DEM, using the Soil and Water Assessment Tool (SWAT) model. In this analysis we found that the accuracy of CARTOSAT-1 DEM is so best for accurate delineation of a sub-watershed in the management of the watershed, and the coarse spatial resolution SRTM DEM (90 m) performed much better and significantly than the high spatial resolution ASTER DEM (30 m) it’s cause of the errors in the ASTER DEM, map algebra was used to define where the “Fill” tool had filled the sinks finding that the errors in the stream network occurred where some especially large fills had occurred. Not only the visual interpretation of the produces figures indicate the SRTM DEM delineated sub-watershed as relatively more accurate from ASTER DEM delineated sub-watershed boundaries, also statistics for the SRTM DEM elevation turned in significantly higher than that of the ASTER DEM. Overall SRTM DEMs offer more precise elevations while, ASTER DEMs offer more details. Therefore, the accuracy of the sub-watershed delineation depends on the first place on the accuracy of the DEM.

Combined Efficiency of RPC and DEM Accuracy on Georeferencing Accuracy of Orthoimage: Case Study With Pléiades Panchromatic Mono Image

Generation of orthoimages in remote sensing and photogrammetry is a common and sometimes mandatory issue. The desired georeferencing accuracy of the orthoimage depends on two main factors: accuracy of transformation parameters and density and accuracy of height information. The objective of this letter is to estimate the combined efficiency of accuracies of refined rational polynomial coefficients and digital elevation models on georeferencing accuracy of the orthoimage utilizing the figure condition method (FCM). In this letter, details of the method, the characteristics of the evaluated Pléiades panchromatic mono image and auxiliary data, and also the test site are presented. The findings were compared with other results from high-resolution satellite images such as those from IKONOS, QuickBird, and OrbView-3. It is observed that the FCM might be preferred to estimate the overall georeferencing accuracy of an orthoimage, reaching ± 0.3-2.7-pixel accuracy range. The Pléiades panchromatic mono image presents almost equal accuracy as the compared images. The research was carried out on the Zonguldak (Turkey) test site which has mountainous and extremely undulating topography.

Research on Block Adjustment of Airborne InSAR Images

Airborne InSAR system and InSAR data processing algorithm have been one of the hot topics in the international SAR field. Geometric constraint relation of images is set up through airborne InSAR block adjustment, adjustment parameters are adjusted and refined, and the three-dimensional(3D) ground coordinates of tie-points(TPs) are solved according to least squares theory. The number of the ground control points(GCPs) is reduced. The airborne InSAR block adjustment experiment was done using self-developed Airborne InSAR Block Adjustment Software System. The 76 airborne InSAR images which are 0.5 m resolution and cover an area of 472 square kilometers generated a block of 4 strips and 19 rows with approximately 30% overlap between adjacent strips. The study site is located in in Jiangyou Sichuan province and characterized by a hilly topography. The result meets DEM and DOM mapping accuracy requirements at scale of 1:10000.

Assessment of cropland area on sloping land in DPRK

Following the famines of the mid 1990s, the government of the Democratic People's Republic of Korea (DPRK) authorized cultivation on sloping land before deciding, in the years 2000, to limit this practice on slopes above 15 degrees in order to reduce erosion. There are still many cultivated fields on slopes and their total estimated area ranges from 300,000 ha to more than 2 million ha. This study aims at assessing cropland areas on slopes above 10 and 15 degrees by using high to very high resolution remote sensing satellite imagery. For this purpose, a grid of points was superimposed over the DPRK territory and stratified according to slope, as derived from two DEMs, the 30 m ASTER GDEM V2 and the 3 arc second (~90 m) SRTM Dem V4. A sample of about 2100 points was drawn using an optimal allocation sampling plan, based on a preliminary assessment of the variance of the estimated cropland percentage per class of slope. These 2100 points were interpreted into cropland, no cropland and doubt using mostly Google Earth imagery acquired after 2004. For slopes above 10 degrees, the area cropped was estimated to be around 1,000,000 ha (5.6% CV) and 742,000 ha (8.1% CV) according to the ASTER and SRTM DEM respectively. Above 15 degrees, the estimated cropland area ranges from 360,000 ha (9.7% CV) with SRTM to 540,000 ha (6.6.% CV) with ASTER. To decide between these two estimations, a validation of the two DEMs should be carried out on a region with similar relief. Alternatively, a higher accuracy DEM such as the one to be derived from the TanDEM-X mission in 2014 should provide more accurate estimates of the cropland area on sloping land.

DEM automatic extraction on Rio de Janeiro from WV2 stereo pair images

The use of three-dimensional data has become, for a lot of mapping applications, very important. DEM are applied for modelling purposes, i.e. the 3D city model generation, but principally for imagery orthorectification. In aerial photogrammetry is well known the suitable use of stereo imagery to produce an accurate DEM, but the limits of the process (cost, schedule of data collection, highly technical staff) and the new advanced digital image processing algorithms have open the work scenario to the remote sensing data. This research has wanted to investigate the possibility to obtain accurate DEMs by means of automatic terrain extraction algorithms implemented in Leica Photogrammetry Suite (LPS) from stereoscopic remote sensing images collected by DigitalGlobe's WorldView-2 (WV2) satellite. The DEM of Rio de Janeiro (Brazil) and the correspondent digital orthoimages have been the results.

Spatial probabilistic approach on landslide susceptibility assessment from high resolution sensors derived parameters

Landslide occurrence depends on various interrelating factors which consequently initiate to massive mass of soil and rock debris that move downhill due to the gravity action. LiDAR has come with a progressive approach in mitigating landslide by permitting the formation of more accurate DEM compared to other active space borne and airborne remote sensing techniques. The objective of this research is to assess the susceptibility of landslide in Ulu Klang area by investigating the correlation between past landslide events with geo environmental factors. A high resolution LiDAR DEM was constructed to produce topographic attributes such as slope, curvature and aspect. These data were utilized to derive second deliverables of landslide parameters such as topographic wetness index (TWI), surface area ratio (SAR) and stream power index (SPI) as well as NDVI generated from IKONOS imagery. Subsequently, a probabilistic based frequency ratio model was applied to establish the spatial relationship between the landslide locations and each landslide related factor. Factor ratings were summed up to obtain Landslide Susceptibility Index (LSI) to construct the landslide susceptibility map.

고해상도 SAR 영상의 기하 위치정확도 관련 중요변수 분석

SAR 위성 영상의 기하 위치정확도는 크게 시스템 내적 변수인 위성 궤도 및 센서 정보와 시스템 외적 변수인 DEM 오차, 대기 지연 등에 영향을 받는다. 이러한 변수들이 현재 운용 중인 다목적실용위성 5호와 개발 중인 다목적실용위성 6호의 영상 내 기하 위치정확도에 미치는 영향을 분석하기 위하여 유사한 제원을 지닌 TerraSAR-X 영상을 이용하여 연구를 수행하였다. 오차 분석을 위해 경사거리 방정식과 도플러 방정식을 이용하여 시뮬레이션 데이터를 생성하였으며, 위성 궤도 변수, 센서 변수, 시스템 외적 변수에 대한 오차를 지상 좌표와 영상 좌표 간 관계식에 반영하여 해당 변수들에 대한 민감도 분석을 수행하였다. 오차 분석을 통해 저궤도 위성의 위치 및 속도 정보로 인한 영상 내 오차는 이중주파수 GPS 데이터 이용에 따라 20cm 내외로 크지 않음이 확인되었다. 따라서 센서관련 변수들이 위치정확도에 영향을 줄 수 있으며, 특히 센서 내 전자적 시간 지연은 경사거리 방향의 정확도에 영향을 크게 미쳐 지속적인 모니터링이 필요할 것으로 판단되었다. 시스템 변수 외에도 DEM 정확도에 의한 오차로 인해 산지지역에서 영상 Geocoding 시 오차가 20~30m까지 크게 발생하고, 대기 지연 현상에 의해 오차는 입사각에 따라 5m까지 발생할 수 있어 영상 활용 시 이에 대한 고려가 필요함이 확인되었다. The geolocation accuracy of SAR satellite imagery is affected by orbit and sensor information and external variables such as DEM accuracy and atmospheric delay. To predict geolocation accuracy of KOMPSAT-5 and KOMPSAT-6, this paper uses TerraSAR-X imagery which has similar spec. Simulation data for sensitivity analysis are generated using range equation and doppler equation with several key error sources. As a result of simulation analysis, the effect of sensor information error is larger than orbit information error. Especially, onboard electronic delay needs to be monitored periodically because this error affects geolocation accuracy of slant range direction by 30m. Additionally, DEM accuracy causes geolocation error by 20~30m in mountainous area and atmospheric delay can occur by 5m in response to atmospheric condition and incidence angle.

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There are very little attempts of DEM evaluation in such a disturbed or discontinuous surface (e.g., in tillage area). Present study aims to evaluate common interpolation methods (triangulation, nearest neighbor, natural neighbor, minimum curvature, multiquadratic radial basis function (MRBF), ordinary kriging, and inverse distance weight) in representing the detail topography of two different tillage types, namely bench terrace and furrow. Evaluation procedure was conducted through a stepwise analysis by using combination between the accuracy level (coefficient of determination (R2), mean error (ME) and standard deviation error (S)) and the shape similarity analysis. This study also shows the application of break-line function during the interpolation process in order to optimize some interpolation methods and the usage of drainage sink area as another step in evaluating DEM quality. To achieve the aim of this study, two field-size of dry-land agriculture (tegalan) were observed by using a set of total station Nikon DTM 322 with 3” angle accuracy. These plots, namely Tieng (1652 m²) and Buntu (673 m²), are situated in the upper part of Wonosobo District, Central Java Province, Indonesia. Tieng plot represents the bench terrace system embedded with stones on its terrace risers and showing relatively smooth ground surface. On the other side, Buntu plot shows the ridges and furrows system that lays perpendicularly to the contour lines. In terms of R², ME and S, there were slight differences in results between each method, except the multiquadratic radial basis function which was failed to generate terrace form in Tieng. The final result shows that triangulation is the best fit method followed by natural neighbour at representing the bench terraces in Tieng plot. In the case of furrow in Buntu plot, natural neighbour is the most accurate method. Despite its superiority at representing the bench terrace, triangulation has larger sink drainage area compared to natural neighbour. This study has confirmed the robustness of a stepwise analysis between quantitative and qualitative assessment techniques for DEM accuracy. A fine value of quantitative parameter does not necessarily mean that it will fairly possess a good spatial accuracy.

Comparison and validation of SRTM and ASTER GDEM for a subtropical landscape in Southeastern China

This paper evaluates the quality characteristics of existing versions of 3-arc-second SRTM and 1-arc-second GDEM over Anji County, Zhejiang, China using reference elevations from a high-quality 1:10 k topographic map. Results show that SRTM has higher accuracy (RMSE =12.44 m) than GDEM (RMSE=14.20 m for Version 1, 12.76 m for Version 2); however, unsatisfactory void filling and an overall 1/2 pixel shift exits in SRTM version 4.1. Although spurious elevations over omitted water bodies still persist, GDEM Version 2 demonstrated significant improvement over Version 1. Accuracies of both SRTM and GDEM decrease on steeper slopes. Aspect also influences both the magnitude and the sign of errors. DEM accuracy in non-forested areas is considerably higher than that in forested areas. SRTM version 4.1 and GDEM version 2 possessed actual spatial resolutions of 90 m, despite both of them failed to match their nominal accuracies. SRTM Version 4.1 could be the first choice, while ASTER GDEM Version 2 would be a good alternative for areas where extensive voids exist in SRTM.

Establishes the Precise Three-Dimensional Terrain Method Study Based on Anudem

Take a typical region in the Loess Plateau of North Shaanxi Province zone as the study area.Based on relief map with a scale of 1:1000 to generate accurate 3D terrain DEM using Anudem algorithm. Compared with the production of Anudem method TIN method and Kriging method between DEM. DEM accuracy evaluation including value target, profile and slope and terrain attribute visualization, contour line playbacking and different differential value algorithm result variance analysis. The DEM difference that the result demonstrates that the different algorithm obtains is big, and DEM precision of Anudem method production is best, can very good response precise three-dimensional terrain.

Extraction of High Resolution DEM from Cartosat-1 Stereo Imagery using Rational Math Model and Its Accuracy Assessment for a Part of Snow Covered NW-Himalaya

This paper reports the experiments carried out for extraction of DEMs from Cartosat-1 stereo imagery using stereo correlation technique for Manali region. The focus of this paper was to assess the accuracy of extracted DEM with respect to DGPS observations, DEM generated from digitized contours of Survey of India (SoI), 1:50,000 scale topographic map(converted to ellipsoidal height using egm2008 geoid model) as well as well-known freely available DEMs ASTER GDEM and SRTM. The vertical accuracy of Cartosat-1 DEMs was analysed with DGPS derived ground control points. The relative vertical accuracy (root mean square error; RMSE) of Cartosat-1 DEM with DGPS control points was ±9.6 m. The RMSE with the topographic DEM was found to be ±10.6 for 22 spot heights and ±10.8 m for 6,458,800 checkpoints. The relative vertical accuracy assessment is more important than the absolute vertical accuracy assessment. The result of relative accuracy assessment of DEMs with respect to field measurement of DGPS points and reference DEMs shows Cartosat-1 DEM is more accurate when compared to ASTER DEM, SoI Topographic DEM, and SRTM DEM for Manali region.

Quantifying and modelling the impact of land consolidation and field borders on soil redistribution in agricultural landscapes (1954–2009)

Soil erosion rates in cultivated areas have intensified during the last decades leading to both on and off-site problems for farmers and rural communities. Furthermore, soil redistribution processes play an important role in sediment and carbon storage within, and exports from, cultivated catchments. This study focuses on the impact of land consolidation and changes in landscape structure on medium term soil erosion and landscape morphology within a 3.7-ha field in France. The area was consolidated in 1967 and we used the Cs-137-technique to quantify soil erosion for the period (1954-2009). We measured the Cs-137 inventories of 68 soil cores sampled along transects covering the entire area and especially specific linear landforms located along both present and past field borders (i.e., lynchets and undulations landforms, respectively). These results were then confronted with the outputs of a spatially-distributed Cs-137 conversion model that simulates and discriminates soil redistribution induced by water and tillage erosion processes. Our results showed that tillage processes dominated the soil redistribution in our study area for the last 55 years and generated about 95% (i.e., 4.50 Mg.ha(-1).yr(-1)) of the total gross erosion in the field. Furthermore, we demonstrated that soil redistribution was largely affected by the presence of current and also former field borders, where hotspots areas of erosion and deposition (>20 Mg.ha(-1).yr(-1)) were concentrated. Land consolidation contributed to the acceleration of soil erosion through the conversion of depositional areas into sediment generating areas. Although the conversion model was able to reproduce the general tendencies observed in the patterns of Cs-137 inventories, the model performance was relatively poor with a r(2) of 0.20. Discrepancies were identified and associated with sampling points located along the current field borders. Our data suggests that tillage erosion processes near field boundaries cannot be described as a typical diffusive process. These processes near field boundaries should be characterised and taken into account in a future version of the model to accurately simulate rates and patterns of past soil redistribution in fragmented cultivated hillslopes. We also showed that the use of an accurate DEM resulting from LIDAR data, based on present-day topography, leads to the underestimation of soil redistribution rates by the model, especially in this landscape submitted to recent and important morphological changes. Our results have important implications for the simulation of tillage erosion processes and our understanding of soil redistribution processes in complex cultivated areas. This is of particular interest to improve our knowledge and prediction of patterns of soil physical parameters, such as carbon storage or water content, particularly sensitive to surface erosion and landscape structuration. Anglais

RAPID GEOMETRIC CORRECTION OF SSC TERRASAR-X IMAGES WITH DIRECT GEOREFERENCING, GLOBAL DEM AND GLOBAL GEOID MODELS

Abstract. In this paper a process for rapid geometric correction of slant range SAR images is presented. The process is completely independent of ground control information thanks to the direct georeferencing method capabilities offered by the TerraSAR-X sensor. The process is especially rapid due to the use of readily available global DEMs and global geoid models. An additional advantage of this process is its flexibility. If a more accurate local DEM or local geoid model is readily available it can be used instead of the global DEM or global geoid model. The process is applied to geometrically correct a SSC TerraSAR-X image over a sub-urban mountainous area using the SRTM and the ASTER global DEMs and the EGM2008 global geoid model. Additionally two local, more accurate DEMs, are used. The accuracy of the process is evaluated by independent check points.

EVALUATION OF SAR DATA AS SOURCE OF GROUND CONTROL INFORMATION: FIRST RESULTS

Abstract. The high resolution imaging modes of modern SAR sensors has made SAR data compatible with optical images. SAR data offers various capabilities which can enhance the geometric correction process of optical images (accurate, direct and ground-independent georeferencing capabilities and global DEM products). In this paper the first results of an on-going study on the evaluation of SAR data as source of ground control information for the georeferencing of optical images are presented. The georeferencing of optical images using SAR data is in fact a co-registration problem which involves multimodal, mutitemporal, and multiresolution data. And although 2D transformations have proved to be insufficient for the georeferencing process, as they can not account for the distortions due to terrain, quite a few approaches on the registration of optical to SAR data using 2D-2D transformations can still be found in the literature. In this paper the performance of 2D-2D transformations is compared to the 3D-2D projective transformation over a greater area of Earth’s surface with arbitrary terrain type. Two alternative forms of ground control information are used: points and FFLFs. The accuracy of the computed results is obtained using independent CPs and it is compared to the geolocation accuracy specification of the optical image, as well as to the accuracy of exhaustive georeferencing done by third parties.