Acceptable Raster Registration Error
Contents |
1: Georeferencing a DRG
        Georeferencing a raster image involves placing control points and performing either a first order (affine) or 2nd order polynomial coordinate transformation.   Associated with any of these transformation methods is some error.  We will be discussing this error known as the RMS error (the root mean squareError In Gis
error) and what is a "reasonable" RMS Error.  According to the accepted definition of a precision error definition reasonable RMS error:  RMSei is less than or equal to 1/2 of the side of a cell which make up the total
Difference Between Accuracy And Error
resolution of th image.   In this case we have a scanned DRG quad map from the USGS with a map scale of 1 inch measured equals 24,000 inches on the ground, or in the case error and accuracy tok of cells we have 1 inch equivalent to 250 cells.   Upon converting to meters we end up with 609.60 meters/measured inch.  Now calculating meters/cell (609.60/250 = 2.4384 meters/cell).  By definition we end up with an RMS error of 2.4384/2 = 1.22 meters.  Now the question remains how does this compare with the RMS error resulting from the placing of our map control points and substituting the the real world x and y precision error formula coordinates into the link table?  Well in this case the results compared quite favorably with the link table value coming in at 1.04174 (see figure 1 below).   After deleting and replacing control points a couple of times I settled with this value being acceptable according to the less than or equal to cell side/2 rule.
  Figure 1: Screen Capture of the State College DRG complete with image of Link Table         When considering whether or not an RMS value has any diagnostic value a technician must first ask if the projection and resolution of the scanned map are known?   If so then it is possible to determine the map units and length of a cell side since the scale is known.   In the case of the statecollegege_DRG.tif shown in the background of figure 1 (above) this is all true, therfore we can say that the RMS value in this case has diagnostic value.  Now asking the question as to what might limit a technicians ability to arrive at a low RMS error when georeferencing raster data.   There are potentially 3 reasons which all could contribute to this limiting factor 1:  Incorrectly correlated and digitized ground control point locations in source and projected data. 2:  poor choice of reference point locations or 3:  damagedBadges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the
4 Potential Sources Of Error In A Gis
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State Three Possible Sources Of Error
GIS professionals. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Georeferencing Raster automatically fails http://photographicviewpoints.com/Geo484/Lesson3.html up vote 0 down vote favorite While trying to auto register a raster image in georeferencing - using a wms raster layer as reference - I get the simple error message "Failed to auto register". Thereby the Link Table remains empty. I am currently using ArcGIS Desktop 10.3.1 and followed all the steps in the related ESRI Article (up to #7). The WMS Layer is projected in WGS84, data frame rotation is set to zero. arcgis-desktop raster http://gis.stackexchange.com/questions/183615/georeferencing-raster-automatically-fails wms arcgis-10.3 georeferencing share|improve this question edited Mar 6 at 10:11 PolyGeo♦ 38.8k1357141 asked Mar 6 at 10:01 Fred 92 add a comment| 1 Answer 1 active oldest votes up vote 0 down vote Fred, Did you load the WMS Layer to ArcMap first? It sounded like you may have two different projection within ArcMap. So, I would clear that up in ArcMap and then bring the WMS Layer first then add other layers. I would also check the Layers at the TOC (Table of Contents) and right click on it and click on the tab on Coordinate Systems to check which projection ArcMap uses. Can you explain to us what you were trying to do? share|improve this answer answered Mar 6 at 15:58 PROBERT 2,12112249 Hi Probert, basically I am trying to use a certain part of this WMS in order to georeference a corresponding layer. First I export the visible area by "File->Export Map". Then I drag the new png (or tiff, jpg etc.) onto the Data Frame with the WMS in it. The match of both is perfect, but the exported raster image lacks the spatial reference. The main reason for me trying to georeference my raster that way, is the slow server of my workplace, which takes forever to load single raster images of the WMS (which we use for ge
R- istration (WBIR). Previous WBIRs took place in Bled, Slovenia (1999), at the UniversityofPennsylvania,USA(2003)andinUtrecht,TheNetherlands(2006). This year, WBIR was hosted by the Institute Mathematics and Image Proce- ing and the...https://books.google.com.ph/books/about/Biomedical_Image_Registration.html?id=LSCyAXI3jvkC&utm_source=gb-gplus-shareBiomedical Image RegistrationMy https://books.google.com/books?id=LSCyAXI3jvkC&pg=PA64&lpg=PA64&dq=acceptable+raster+registration+error&source=bl&ots=A7J7Ng7QK1&sig=butXQezwD72Py9saQXMquEpuMs0&hl=en&sa=X&ved=0ahUKEwiv4ren0KnPAhWl4IMKHWWbAmsQ6AEIOjAE libraryHelpAdvanced Book SearchView eBookGet this book in printSpringer ShopAmazon.comNational http://www.personal.psu.edu/users/c/l/clw300/484_Project_1.html BookstorePowerbooksFind in a libraryAll sellers»Biomedical Image Registration: 4th International Workshop, WBIR 2010, Lübeck, July 11-13, 2010, ProceedingsBernd FischerSpringer Science & Business Media, 5 Jul 2010 - Computers - 280 pages 0 Reviewshttps://books.google.com.ph/books/about/Biomedical_Image_Registration.html?id=LSCyAXI3jvkCWelcome to the proceedings of the 4th Workshop error in on Biomedical Image R- istration (WBIR). Previous WBIRs took place in Bled, Slovenia (1999), at the UniversityofPennsylvania,USA(2003)andinUtrecht,TheNetherlands(2006). This year, WBIR was hosted by the Institute Mathematics and Image Proce- ing and the Fraunhofer Project Group on Image Registration and it was held in Lub ̈ eck, Germany. It provided error in gis the opportunity to bring together researchers from all over the world to discuss some of the most recent advances in image registration and its applications. We had an excellent collection of papers that were reviewed by at least three reviewers each from a 35-member Program Committee assembled from a wor- wide community of registration experts. This year 17 papers were accepted for oral presentation, while another 7 papers were accepted as poster papers. We believe all of the conference papers were of excellent quality. Registration is a fundamental task in image processing used to match two or more pictures taken, for example, at di?erent times, from di?erent sensors, or from di?erent viewpoints. Establishing the correspondence of structures within medical images is fundamental to diagnosis, treatment planning, and surgical guidance. The conference papers address state-of-the-art techniques for prov- ing reliable and e?cient registration techniques, thereby impos
system. Often times when building and using GIS systems, scanned maps, photographs or satellite images are used to digitize features or see area specifics (Sloan, 2007). However, scanned maps or photos do not normally contain spatial reference information and therefore they need to be georeferenced in order to align properly to the existing data. When you georeference a dataset, you are ultimately defining its location using map coordinates and assigning a coordinate system. Georeferencing raster data allows it to be viewed, queried, and analyzed with other geographic data (ESRI, 2005). The process of georeferencing actually comes about via one of four transformation methods. In this lesson we will apply two different transformation methods to three different datasets, via two software techniques (Sloan, 2007): Using an affine transformation, and explicit XY coordinates of control points, we will georeference a USGS DRG that has "lost" its georeferencing information. Using an affine transformation and explicit XY coordinates of control points, we will georeference a scanned portion of a paper version of the same USGS topo quad represented by the DRG above. Using a second-order polynomial transformation, we will attempt to georeference a vertical aerial photograph (not orthorectified) by using an interactive tool to specify pairs of control points. Figure 1. Screen capture showing A) State College DRG as the active layer, B) the link table that shows the 4 links with the data values supplied in the table, the 1st Order Polynomial (Affine) Transformation method, and the RMS error, and 3) the coordinate readout at the bottom of the view screen in Meters. Figure 2. Screen capture showing A) State College Map as the active layer, B) the link table that shows the 4 links with the data values supplied in the table, the 1st Order Polynomial (Affine) Transformation method, and the RMS error, and 3) the coordinate readout at the bottom of the view screen in Meters. Figure 3. Screen capture showing A) S