Systems for data processing, anaylsis and representation

Allam, Mosaad; Plunkett, Gordon

Bibliographic data

Monograph

Persistent identifier:: 1067490280

Title:: Systems for data processing, anaylsis and representation

Sub title:: ISPRS Commission II Symposium : June 6 - 10, Ottawa, Canada

Scope:: 1 Online-Ressource (XX, 530 Seiten)

Year of publication:: 1994

Place of publication:: Ottawa

Publisher of the original:: The Surveys, Mapping and Remote Sensing, Natural Resources Canada

Identifier (digital):: 1067490280

Illustration:: Illustrationen

Signature of the source:: ZS 312(30,2)

Language:: English

Additional Notes:: Erscheinungsdatum des Originals ist aus dem Copyrightjahr ermittelt.

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Editor:: Allam, Mosaad; Plunkett, Gordon

Corporations:: Symposium Systems for Data Processing, Analysis and Representation, 1994, Ottawa; International Society for Photogrammetry and Remote Sensing; International Society for Photogrammetry and Remote Sensing, Commission Instrumentation for Data Reduction and Analysis; Kanada, Surveys, Mapping and Remote Sensing Sector

Adapter:: Symposium Systems for Data Processing, Analysis and Representation, 1994, Ottawa; International Society for Photogrammetry and Remote Sensing; International Society for Photogrammetry and Remote Sensing, Commission Instrumentation for Data Reduction and Analysis; Kanada, Surveys, Mapping and Remote Sensing Sector

Founder of work:: Symposium Systems for Data Processing, Analysis and Representation, 1994, Ottawa; International Society for Photogrammetry and Remote Sensing; International Society for Photogrammetry and Remote Sensing, Commission Instrumentation for Data Reduction and Analysis; Kanada, Surveys, Mapping and Remote Sensing Sector

Other corporate:: Symposium Systems for Data Processing, Analysis and Representation, 1994, Ottawa; International Society for Photogrammetry and Remote Sensing; International Society for Photogrammetry and Remote Sensing, Commission Instrumentation for Data Reduction and Analysis; Kanada, Surveys, Mapping and Remote Sensing Sector

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2019

Document type:: Monograph

Collection:: Earth sciences

Chapter

Title:: [Thursday, June 9, 1994]

Document type:: Monograph

Structure type:: Chapter

Chapter

Title:: [Joint ISPRS/GIS '94 Plenary IV]

Document type:: Monograph

Structure type:: Chapter

Chapter

Title:: DIGITAL PHOTOGRAMMETRIC SYSTEMS AND THEIR INTEGRATION WITH GIS IAN DOWMAN

Document type:: Monograph

Structure type:: Chapter

Operations can be automated entirely or in - part. An example of partial automation, or computer assisted operations is when the operator sets an approximate position and the final position is fixed automatically. This allows the computer to perform the difficult operation and usually to achieve maximum precision. An example is the line extraction routine in the ISTAR VUE3D system in which the operator roughly indicates the position of a line and the computer finds the exact line of the feature using a dynamic programming technique developed by Mâitre and Wu (1989). The stereo matching of two images to ensure correct height when the operator follows a feature is another example which was introduced in the Kern DSP1 and is now incorporated into a number of systems. In the production systems automation does not tend to be introduced until a robust algorithm has been developed and proven. Thus most systems still rely on the operator to carry out the inner, relative and absolute orientation with support from image processing routines such as zooming. Software for the production of DEMs is now is use for production and DEMs can be produced automatically but still need to be edited for blunders and missing areas. 3.3 Research directions With the exception of the DEM extraction, no commercial systems has a proven automated component. It is evident from the literature that there are a number of areas where automation is seen as having a potential, either in the near or distant future. These areas are: * identification of ground control points; * Speeding up the orientation process necessary to determine the exterior orientation of the images; * feature extraction; * change detection. 3.3.1 Automatic GCP extraction There is a significant amount of work going on to reduce the dependence on ground control points (GCPs) for absolute orientation and georeferencing procedures. The identification and selection of GCPs for geometric processing of digital images is usually a time-consuming and expensive process although discussion with producers indicates that this is a small proportion of the total cost of producing image maps. Automatic 340 matching with earlier processed images is a significant help in removing this bottle-neck. This has been discussed and implemented for a number of years, for example Benny (1981). A major problem to be addressed is the accuracy and distribution of extracted points. The problem of map-image matching is much more difficult as work by UCL has shown (Stevens et al 1988). Building on earlier work (Schenk et. al. 1991) on automatic tie-point determination for the orientation of digital photographs, Toth and Schenk (1992) have described a method of automatically registering images by matching extracted edges and determining identical points. 3.32 Automation within the orientation process In order to determine the orientation elements it is necessary to establish the calibration parameters of the sensor and to fix relative orientation and absolute orientation using ground reference points. The points required for calibration and relative orientation (conjugate points) can already be determined automatically. The fiducial points and the conjugate image coordinates can be derived from stereo matching. Stokes (1988) developed a fully automated procedure to identify and measure fiducial marks. Fiducial marks are generally different in different cameras. However, they usually have a well defined appearance and occupy an extended area devoid of other information. Their degree of symmetry is high and their approximate location in the image known in advance. They can therefore easily be identified using template matching and then localised with centre of gravity methods. Haala et al (1993) have described work leading to full automation of the conjugate point problem starting with an interest operator and using an image pyramid to refine the match. A number of organisations are working with image registration systems which consider whole images (Lee et al, 1993) or layers in images such as roads (ENST in Paris using techniques described by Maitre and Wu, 1989). Schickler (1992) developed a system for automating the exterior orientation of a single image. It is based on control points which consist of a list of straight 3D-line segments, whose 3D-coordinates are known in a object centred coordinate system, and which mostly repre valuc to in the ir segir imag avail resec segim preci This of di: phot more point space plan: their for i techi essel than orde extrz featu must WOrk geon perf phot Haal relat desc insta back struc obtai colo linea the | map: been Syst 3.3.3 Feat inter defir robu McK majc varia othe: Syste comi rese: the relat with mult

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