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Aerial_Imagery/OC3_1967_LowRes (ImageServer)

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Service Description: There is positional error inherent in the ortho-rectification of the photo (ranging from 3-15 meters, but usually about 3 meters) GROUND POINT MEASUREMENT & TRIANGULATION : The collection of "Ground Control Points" (GCPs) refers to identifying certain features in each photo whose geographical coordinates can be provided. Each individual raw photo had an average of at least 3 GCPs and about 7 or more Tie Points. The GCPs were obtained using the 2005 reference orthophotos to determine the geographical coordinates of features (e.g., road intersections) that were visible in both the 2005 and 1967 photos. The same feature was then identified graphically in the un-registered 1967 photo. Often, when road intersections or houses were not available, natural features were used, such as large boulders on the beach arranged in a recognizable pattern. The entire suite of 1611 photos along the entire coastline of Oregon were broken up into 48 individual "blocks", and each one was GCP-measured and triangulated separately. Triangulation refers to the very quick process of hitting the "Triangulate" button and finding out whether or not the Ground Control Points (GCPs) fit together like a puzzle in a mathematically robust way. There is a resultant "Total RMS" error that indicates how well the geometry of the GCPs "converged". Convergence values greater than 4 meters were chosen as a threshold to indicate a problem and that GCPs had to be re-measured. The maximum positioning error of a single GCP was 16.37 meters; that was in a block whose block-average error was 4.61 meters. The average "Total RMS error" throughout all 48 blocks was 2.96 meters, and the average "Maximum error" of each of the 48 blocks was 10.70 meters. ORTHO-RECTIFICATION: After triangulation, the creation of ortho-photos is straightforward and simple. It creates a new photo from the original raw photo by applying the mathematically converged geometry to the old photo. The new, ortho-rectified photo has a geographical coordinate (Easting and Northing) associated with each pixel. Features outside the center of photo are affected by the radial distortion of the camera lens and by the elevation changes of the terrain. These two factors can cause a feature (e.g., a house) to be incorrectly moved inward or outward from the center of the photo. The ortho-rectification process incorporates the radial distortion parameters for the given camera lens as well as the terrain model (Digital Elevation Model) to correct for these factors and move the feature to its correct location in the photo.

Name: Aerial_Imagery/OC3_1967_LowRes

Description: There is positional error inherent in the ortho-rectification of the photo (ranging from 3-15 meters, but usually about 3 meters) GROUND POINT MEASUREMENT & TRIANGULATION : The collection of "Ground Control Points" (GCPs) refers to identifying certain features in each photo whose geographical coordinates can be provided. Each individual raw photo had an average of at least 3 GCPs and about 7 or more Tie Points. The GCPs were obtained using the 2005 reference orthophotos to determine the geographical coordinates of features (e.g., road intersections) that were visible in both the 2005 and 1967 photos. The same feature was then identified graphically in the un-registered 1967 photo. Often, when road intersections or houses were not available, natural features were used, such as large boulders on the beach arranged in a recognizable pattern. The entire suite of 1611 photos along the entire coastline of Oregon were broken up into 48 individual "blocks", and each one was GCP-measured and triangulated separately. Triangulation refers to the very quick process of hitting the "Triangulate" button and finding out whether or not the Ground Control Points (GCPs) fit together like a puzzle in a mathematically robust way. There is a resultant "Total RMS" error that indicates how well the geometry of the GCPs "converged". Convergence values greater than 4 meters were chosen as a threshold to indicate a problem and that GCPs had to be re-measured. The maximum positioning error of a single GCP was 16.37 meters; that was in a block whose block-average error was 4.61 meters. The average "Total RMS error" throughout all 48 blocks was 2.96 meters, and the average "Maximum error" of each of the 48 blocks was 10.70 meters. ORTHO-RECTIFICATION: After triangulation, the creation of ortho-photos is straightforward and simple. It creates a new photo from the original raw photo by applying the mathematically converged geometry to the old photo. The new, ortho-rectified photo has a geographical coordinate (Easting and Northing) associated with each pixel. Features outside the center of photo are affected by the radial distortion of the camera lens and by the elevation changes of the terrain. These two factors can cause a feature (e.g., a house) to be incorrectly moved inward or outward from the center of the photo. The ortho-rectification process incorporates the radial distortion parameters for the given camera lens as well as the terrain model (Digital Elevation Model) to correct for these factors and move the feature to its correct location in the photo.

Single Fused Map Cache: false

Extent: Initial Extent: Full Extent: Pixel Size X: 1.6405287813977338

Pixel Size Y: 1.6405287813977338

Band Count: 1

Pixel Type: U8

RasterFunction Infos: {"rasterFunctionInfos": [{ "name": "None", "description": "", "help": "" }]}

Mensuration Capabilities: None

Has Histograms: true

Has Colormap: false

Has Multi Dimensions : false

Rendering Rule:

Min Scale: 0

Max Scale: 0

Copyright Text: This dataset was developed by the Southwest Washington Coastal Erosion Study, Coastal Monitoring & Analysis Program, Washington State Department of Ecology, with funding by the United States Geological Survey.

Service Data Type: esriImageServiceDataTypeGeneric

Min Values: 1

Max Values: 254

Mean Values: 127.77142179768254

Standard Deviation Values: 48.20294127114741

Object ID Field: OBJECTID

Fields: Default Mosaic Method: Northwest

Allowed Mosaic Methods: NorthWest,Center,LockRaster,ByAttribute,Nadir,Viewpoint,Seamline,None

SortField:

SortValue: null

Mosaic Operator: First

Default Compression Quality: 75

Default Resampling Method: Bilinear

Max Record Count: 1000

Max Image Height: 4100

Max Image Width: 15000

Max Download Image Count: 20

Max Mosaic Image Count: 20

Allow Raster Function: true

Allow Copy: true

Allow Analysis: true

Allow Compute TiePoints: false

Supports Statistics: true

Supports Advanced Queries: true

Use StandardizedQueries: true

Raster Type Infos: Has Raster Attribute Table: false

Edit Fields Info: null

Ownership Based AccessControl For Rasters: null

Child Resources:   Info   Histograms   Statistics   Key Properties   Legend   Raster Function Infos

Supported Operations:   Export Image   Query   Identify   Compute Histograms   Compute Statistics Histograms   Get Samples   Compute Class Statistics   Query Boundary   Compute Pixel Location   Validate   Project