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New Member
Posts: 1
Registered: ‎07-07-2019

Automatic extraction of coastline using SPOT 5 satellite imagery

Hi.

In my project Ineed to extract a coastline from a SPOT 5 image. Dose any one please can give a hand how to  perform it using  Spatial modeler. Thanks 

Technical Evangelist
Posts: 799
Registered: ‎10-01-2015

Re: Automatic extraction of coastline using SPOT 5 satellite imagery

Hi,

 

a Normalised Difference Water Index (NDWI) with manual or automated thresholding should do it. Take a look at this example

 

https://community.hexagongeospatial.com/t5/Spatial-Modeler-Tutorials/Extract-Coastline-from-WorldVie...

 

Cheers

 

Ian Anderson
Chief Product Owner, Desktop Remote Sensing
Hexagon Geospatial
Technical Evangelist
Posts: 799
Registered: ‎10-01-2015

Re: Automatic extraction of coastline using SPOT 5 satellite imagery

Old SPOT 5 data is probably a bit more problematic. This paper should give you some ideas:

 

https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XXXIX-B8/181/2012/isprsarchives-XXXI...

 

So a Spatial Model like this is the basis you want to isolate water pixels:

 

SPOT5water.PNG

 

After that you can add steps to convert to vector features if that's how you want your coastline.

 

Remember to convert the data to Reflectance first and get the bands in the correct order (SPOT 5 is generaly NIR, R, G, SWIR order, but not always!)

 

Cheers

 

Ian Anderson
Chief Product Owner, Desktop Remote Sensing
Hexagon Geospatial