ID: 53197
Title: Evaluation of the RPC model for spaceborne SAR imagery
Author: Guo Zhang, Wen-bo Fei, Zhen Li, Xiaoyong Zhu, and De-ren Li
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Rational polynomial coefficient (RPC) model, SAR imagery
Abstract: The rational polynomial coefficient (RPC) model has raised considerable interest in the photogrammetry and remote sensing community. Much work has been done on frame camera imagery and /or push-broom scanner imagery, and it has been widely accepted that the RPC model can be taken as an alternative to rigorous sensor models for photogrammetric processing. However, there have been few publications discussing the application of the RPC model to SAR image processig. In this paper, we first review the geometric effects of SAR imagery and compare SAR imagery with optical satellite imagery. Then, the unbiased RPC estimates for a series of SAR images are derived. Based on numerous tests with the rigorous sensor model available, the modeling error of the RPC is analyzed. This study found that the RPC model is suitable for SAR imagery and can be used as a replacement for the rigorous sensor model for photogrammetric processing.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53196
Title: Detecting seasonal changes in crop community structure using day and night digital images
Author: Toshihiro Sakamoto, Michio Shibayama, Eiji Takada, Akihiro Inoue, Kazuhiro Morita, Wataru Takahashi, Shigenori Miura, and Akihiko Kimura
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Day and night digital images, NRBINIR (Nighttime Relative Brightness Index in Near Infra Red), digital cameras
Abstract: This study investigates a simple approach using day and night digital images to objectively measure seasonal changes in crop morphology. A paddy field in the Toyama prefecture and a barley field in teh Ibaraki prefecture of Japan were observed by two cmmercially available digital cameras in simple waterproof cases which captured day and night images by shooting at regular intervals using an auto-flash mode. The newly developed NRBINIR (Nighttime Relative Brightness Index in Near Infra Red), based on the nighttime NIR images, had high correlations with plant length until heading (paddy; R2 = 0.996, barley; R2 = 0.996), and the total dry weight until 20 days after heading (paddy; R2 = 0.997). Investigating the temporal pattern of the three indexes (daytime NDVIGR, nighttime NDVIGR, and NRBINIR) coupled with field measurement data, we confirmed that the time-series data derived from inexpensive, specifically modified digital cameras are available for monitoring the seasonal changes in crop growth.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53195
Title: Effects of topographic variability and Lidar sampling density on several DEM interpolation methods
Author: Qinghua Guo, Wenkai Li, Hong Yu and Otto ALvarez
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Coefficient variation of elevation (CV), lidar (Light Detection and Ranging), DEM (Digital Elevation Model), natural neighbor (NN), inverse distance weighted (IDW), triangulated irregular network (TIN), spline, ordinary kriging (OK), universal kri
Abstract: This study aims to quantify the effects of topographic variability (measured by coefficient variation of elevation, CV) and lidar (Light Detection and Ranging) sampling density on the DEM (Digital Elevation Model) accuracy derived from several interpolation methods at different spatial resolutions. Interpolation methods include natural neighbor (NN), inverse distance weighted (IDW), triangulated irregular network (TIN), spline, ordinary kriging (OK), and universal kriging (UK). This study is unique in that a comprehensive evaluation of the combined effects of three influencing factors (CV, sampling density, and spatial resolution) on lidar-derived DEM accuracy is carried out using different interpolation methods. Results indicate that simple interpolation methods, such as IDW, NN, and TIN, are more efficient at generating DEMs from lidar data, but kriging-based methods, such as OK and UK, are more reliable if accuracy is the most important consideration. Moreover, spatial resolution also plays an important role when generating DEMs from lidar data. Our results could be used to guide the choice of appropriate lidar interpolation methods for DEM generation given the resolution, sampling desity, and topograhic variability.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53194
Title: Mapping Lantana camara: Accuracy comparison of various fusion techniques
Author: Subhashni Taylor, Lalit Kumar, and Nick Reid
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Panchromatic QuickBird , Multi-spectral QuickBird, satellite imagery, fusion techniques, Brovey, Hue-Saturation-Value, Principal Components, Gram-Schmidt Spectral Sharpening, kappa coefficient
Abstract: Fusion of panchromatic and multi-spectral QuickBird satellite imagery was carried out to evaluate the impact of fusion techniques on classification accuracies for Lantana mapping. This study compared four image fusion techniques, namely Brovey, Hue-Saturation-Value, Principal Components, and Gram-Schmidt Spectral Sharpening. Classification accuracy assessment was calculated using an error martix for all images. Gram-Schmidt and Principal Components spectral sharpening techniques had an overall accuracy of 90.5 percetn and 89.5 percent and a kappa coefficient of 0.85 and 0.84, respectively, compared to the MS image which had an overall accuracy of 86.3 percent and a kapa coefficient of 0.79. Brovey transformation and HSV performed poorly in the supervised classification with overall accuracies of 64.2 percent and 76.8 percent and kappa coefficients of 0.48 and 0.65, respectively. Visual and statistical anlayses of the fused images showed that Gram-Schmidt and Principal Components spectral sharpening techniques preserved spectral quality much better than Brovey and HSV fused images.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53193
Title: A novel approach to terrestrial Lidar georeferencing
Author: Benjamin E. Wilkinson, Ahmed H. Mohamed, Bon A. Dewitt, and Gamal H. Seedahmed
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Lidar, GPS, Non-linear georeferencing model, skew-symmetric matrix, Euler attitude angles
Abstract: This paper describes a novel method for determining the absolute orientation of lidar point clouds using GPS measurements from two antennas firmly mounted on the optical head of a lidar scanner. The solution is linear and is derived from the non-linear georeferencing model by exploiting the properties of the skew-symmetric matrix. Simulation and real world experimentation using our prototype suggest a precision of about 0.050 (~1 mrad) for the three Euler attitude angles. The method can help alleviate problems associated with the conventional technique and can allow for an increased number of practical applications for georeferenced terrestrial lidar.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53192
Title: A pixel based regeneration index using time series similarity and spatial context
Author: Stefaan Lhermitte, Jan Verbesselt, willem W. Verstraeten, and Pal Coppin
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Regeneration index, vegetation regrowth, Time Series Similarity (TSS)
Abstract: Although the regeneration index based on control plots provides a valuable tool to quantify fire impact and subsequent vegetation tool to quantify fire impact and subsequent vegetation regrowth, the practical implementation at large scale levels remains limited due to the need for detailed reference maps. The objective of this research therefore was the development of an image-based selection approach for control pixels based on time series similarity (TSS). The TSS approach allows the computation of a per pixel regeneration index on regional to global scale without the need for reference maps. Evaluation of the control plot selection approaches based on un-burnt focal pixels confirmed the validity of the TSS approach and showed optimal results for the TSSRMSD approach with x = 4 and NT = 8 due to beneficial averaging effects and minimal window size effects. As such, the effects of spatial heterogeneity and noise are minimized and a preliminary quality indicator can be derived.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53191
Title: Acquisition, Orthorectification, and Object-based classification of unmanned Aerial Vehicle (UAV) Imagery for Rangeland Monitoring
Author: Andrea S. Laliberte, Jeffrey E. Herrick, Albert Rango, and Craig Winters
Editor: Russell G. Congalton
Year: 2010
Publisher: ASPRS, Vol 76, No 6, June 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Photogrammetric Engineering & Remote Sensing
Keywords: Unmanned Aerial Vehicles (UAVs), orthorectified image mosaics, Rangeland monitoring
Abstract: The use of unmanned aerial vehicles (UAVs) for natural resource applications has increased considerably in recent years due to their greater availability, the miniaturization of sensors, and the ability to deploy a UAV relatively quickly and repeatedly at low altitudes. We examine in this paper the potential of using a small UAV for rangeland inventory, assessment and monitoring. Imagery with a ground resolved distance of 8 cm was acquired over a 290 ha site in southwestern Idaho. We developed a semi-automated orthorectification procedure suitable for handling large numbers of small-footprint UAV images. The geometric accuracy of the orthorectified image mosaics ranged from 1.5 m to 2 m. We used object-based hierarchical image analysis to classify imagery of plots measured concurrently on the ground using standard rangeland monitoring procedures. Correlations between image-and ground-based estimates of percent cover resulted in r-squared values ranging from 0.86 to 0.98. Time estimates indicated a greater efficiency for the image-based method compared to ground measurements. The overall classification accuracies for the two image mosaics were 83 percent and 88 percent. Even under the current limitations of operating a UAV in the National Airspace, the results of this study show that UAVs can be used successfully to obtain imagery for rangeland monitoring, and that the remote sensing approach can either complement or replace some ground-based measurements. We discuss details of the UAV mission, image processing and analysis, and accuracy assessment.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53190
Title: Color correction of texture images for true photorealistic visualization
Author: Yonghak Song, Jie Shan
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Color correction, Photorealistic visualization, Rendering Texture mapping
Abstract: Photorealistic visualization combines 3-D geometric models with their texture images to render the virtual world. This paper points out that the texture images should be radiometrically corrected to achieve a true realistic appearance. Such a correction should include not only the color adjustment among images of the same object, but also the shade variation caused by the illumination change. The objective of this study is to correct the input texture images such that their shade varies when being rendered under different illumination directions. To achieve this goal we first apply teh specular-to-diffuse mechanism based on the dichromatic reflection model to remove the specular component from the texture image. The resultant diffusion-only image then undergoes a shade correction to produce a normalized shade-free texture image. In the final step, shades under any illumination are produced to achieve a true photorealistic effect. Presented in the paper are the principles and methods of such corrections, along with a performance evaluation based on the graphic and numerical results for roof texture images.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53189
Title: Analytical 3D views and virtual globes - scientific results in a familiar spatial context
Author: Dirk Tiede, Stefan Lang
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Information delivery, Analytical spatial information, object-based information extraction, Globe viewer, Conditioned information
Abstract: In this paper we introduce analytical three-dimensional (3D) views as a means for effective and comprehensible information delivery, using virtual globes and the third dimension as an additional information carrier. Four case studies are presented, in which information extraction results from very high spatial resolution (VHSR) satellite images were conditioned and aggregated or disaggregated to regular spatial units. The case studies were embedded in the context of : (1) urban life quality assessment (Salzburg/Austria); (2) post-disaster assessment (Harare/Zimbabwe); (3) emergency response (Lukole/Tanzania); and (4) contingency planning (faked crisis scenario/Germany). The results are made available in different virtual globe environments, using the implemented contextual data (such as satellite imagery, aerial photographs, and auxiliary geodata) as valuable additional context information. Both day-to-day users and high-level decision makers are addresses of this tailored information product. The degree of abstraction required for understanding a complex analytical content is balanced with the east and appeal by which the context is conveyed.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53188
Title: Addressing the value of art in cartographic communication
Author: William E. Cartwright
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Cartography, Design, Art
Abstract: Contemporary methods for depicting the earth and its cultural and natural attributes use graphic and non-graphic formates, maps and map-related artefacts, for visualizing geography and building virtual landscapes and environments. The discipline area of cartography, traditionally, has applied are (design), science and technology to map making to design and realise these products. Prior to the mid-1950s, cartographic artefacts were built under the theoretical and practical ' umbrella ' of this partnership of art, science and technology. However, since then, the theory and methodology associated with visualizing geography has focused on Science and Technology, and away from Art. This ' move ' away from art was accelerated by : (1) computing, computers and completer automated systems: and (2) the ' quest ' to gain ' scientific legitimacy ' by using scientific visualization as a lodestone for gauging the ' quality ' of theories and applications.
Science and Technology has been embrace by cartography as a means to ensure that what is presented is scientifically ' correct ' - products are considered to ' work ' if they are scientifically ' elegant ' , ' technologically ' ' buildable ' and ' deliverable ' using contemporary communication systems. But, it is argued, science or technology, need not always take on primary roles, and there now is a need to address the role that design should take to facilitate the further development of contemporary cartography, especially in the areas where new media has been applied to facilitate the building of georgraphical visualization tools. This paper will address how, by incorporating art elements into the design criteria of geographical visualization artefacts, ' different ' visualization tools might be provided using all three elements of cartography: art, science and technology.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53187
Title: An automatic mosaicking method for building facade texture mapping using a monocular close-range image sequence
Author: Zhizhong Kang, Liqiang Zhang, Sisi Zlatanova, Jonathan Li
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Terrestrial imaging, Digital camera calibration , Mosaicking, Building facade, Texture mapping
Abstract: This paper presents an automatic mosaicking method of generating building facade textures from a monocular close-range digital image sequence. The process begins with the computation of the camera parameters (except the coordinates of the projective centre), which are determined by combining vanishing point geometry with constraints of a straight line bundle as well as prior information of parallel lines in object space. The raw images are later rectified for the purpose of eliminating their salient geometric distortion. Next, automatic retrieval of the relevant image segment is implemented using the detecting range variance by means of the histogram of projective differences between the corresponding points for each of the facades from the raw image sequence. A strip model of the least-squares adjustment, which is similar to the strip block adjustment in aerial triangulation, is employed to determine the spatial alignment of each of the image segments in order to generate the facade textures from the relevant image segments. Afterwards, the entire building facade texture is mosaicked by ortho-image generation. Two refining strategies are proposed to optimize the mosaic result. One is refining the mosaic region where corresponding points ae difficult to match but plenty of horizontal lines are available, and the constraint of corresponding horizontal lines is introduced to implement this process. The other strategy is to refine the unsatisfactory mosaic region by densifying the corresponding points by means of the spatial alignment of the relevant image segment computed by the strip method. The experimental results indicate that this method is widely applicable and compares well with other reported approaches with regard to automation level and applicability, for uncalibrated images as well as images with large geometric distortions.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53186
Title: The development of an integrated technical - methodical approach to visualise hydrological processes in an exemplary post-mining area in Central Germany
Author: C.Glaber, D. Thurkow, Ch. Dette, S. Scheuer
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Web based, Visualisation, Hydrology, Multitemporal, Database
Abstract: The rapid development of software and hardware during the last decade caused a paradigm change in data processing. That is why, in geosciences, monolithic GIS systems are increasingly complemented by web -based services and multimedia content, while geovisualisation is becoming more popular to visualise and analyse geoscientific processes. An increasing realism in geovisualisations tends to result in more complex geodata and metadata, requiring sophisticated solutions for efficient data management. This paper describes an integrated approach to geographic data processing and geovisualisation in a open, modular system. A former open-pit mining area in Central Germany characterised by a highly dynamic landscape and rapidly changing natural and anthropogenic processes has been chosen as an exemplary test site. Here, geovisualisation is used to depict the extreme charges in the landscape. The focus is on hydrological process, which are highly complex and difficult to comprehend. The described approach will show how heterogeneous data can be used to support the understandingand transfer of knowledge.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53185
Title: An evaluation of measures for quantifying map information
Author: Lars Harrie, Hanna Stigmar
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Cartography, Generalisation, Simplification, Visualisation, Analysis
Abstract: A real-time map must not contain too much information. Therefore, we need measures of map information that could be guidelines for the selection of data layers and the real-time generalisation process. In this paper we evaluate measures of the amount of information and the distribution of information. The evaluation is performed by (1) defining measures, (2) implementing the measures, (3) computing the measures for some test maps, and finally (4) comparing the values of the measures with human judgement of the map information. For amount of information, we found that the measures number of objects, number of points and object line length had better correspondence with human judgement than object area. We also found that measures based on the size of Voronoi regions of objects (respectively points) can be used for identifying the distribution of information. The results are based on the testing of only building objects. Future work should extend the test, using all object types.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53184
Title: Augmented paper maps: Exploring the design space of a mixed reality system
Author: Volker Paelke , Monika Sester
Editor: George Vosselman
Year: 2010
Publisher: Elsevier, Vol 65, issue 3, May 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Cartography, Augmented reality, Mobile interfaces
Abstract: Paper maps and mobile electronic devices have complementary strengths and shortcomings in outdoor use. In many scenarios, like small craft sailing or cross-country trekking, a complete replacement of maps is neither useful nor desirable. Paper maps are fail-safe, relatively cheap, offer superior resolution and provide large scale overview. In uses like open-water sailing it is therefore mandatory to carry adequate maps/charts. GPS based mobile devices, on the other hand, offer useful features like automatic positioning and plotting, real-time information update and dynamic adaptation to user requirements. While paper maps are now commonly used in combination with mobile GPS devices, there is no meaningful integration between the two, and the combined use leads to a number of interaction problems and potential safety issues. In this paper we explore the design space of augmented paper maps in which maps are augmented with additional functionality through a mobile device to achieve a meaningful integration between device and map that combines their respective strengths.
Location: 231
Literature cited 1: None
Literature cited 2: None
ID: 53183
Title: Lipids in Photosynthesis: Essential and Regulatory Functions (Advances in photosynthesis and Respiration: Volume (30)
Author: None
Editor: P.Balaram
Year: 2010
Publisher: Current Science Association, Vol 98, No 8, 25 April 2010
Source: Centre for Ecological Science,Indian Institute of Science, Bangalore-12
Reference: None
Subject: Current Science
Keywords: None
Abstract: None
Location: 241
Literature cited 1: None
Literature cited 2: None