**Geometric Correction****geometric correction** - [remote sensing] The correction of errors in remotely sensed data, such as those caused by satellites or aircraft not staying at a constant altitude or by sensors deviating from the primary focus plane.

**Geometric correction** instructions.

Open the image to be corrected in Viewer

Open the Raster **geometric correction** menu

A series of windows will first prompt you to set the **geometric correction** model. Choose polynomial as a generic correction tool.

See Also: **geometric correction**, rectification

[satellite imaging] The process of correcting the geometry of an image so that it appears as though each pixel were acquired from directly overhead. Orthorectification uses elevation data to correct terrain distortion in aerial or satellite imagery.

(1990) **Geometric correction** of airborne scanner imagery by matching Delaunay triangles. International Journal of Remote Sensing 11(12): 2237-2251.

Duggin, M.J., and Robinove, C.J. (1990) Assumptions implicit in remote sensing data acquisition and analysis.

3. The calculation of new DN for pixels created during **geometric correction** of a digital scene, based on the values in the local area around the uncorrected pixels.

Image rubber sheeting functions allow **geometric correction** or registration of an image to a new coordinate system. R2V supports both Bi-linear and Delaunay triangulation methods for geometric transformation.

Often used in the **geometric correction** of remotely sensed images and surveying.

Image: A graphic representation or description of a scene, typically produced by an optical or electronic device. Common examples include remotely sensed data (satellite data), scanned data, and photographs.

For a correct matching, one needs a set of reliable control points in the image which are linked to map co-ordinates in accordance with the method discussed earlier This link is defined by a **geometric correction** model, for instance linear equations, projective equations, ...

See also: Image, Pixel, GIS, Model, Geographic

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