[Qgis-user] Raster to Vector polygons

[Thayer Young]

 Hi Normand,
You might want to try the "Reclassify by table" tool. Depending on how complex your styling is, you can either copy the limits manually into a table or export them as an SLD and open the file in a text editor and transfer them to a table by copy and paste.
https://docs.qgis.org/3.16/en/docs/user_manual/processing_algs/qgis/rasteranalysis.html#qgisreclassifybytable

To save an SLD file of the style go to Layer Properties: Symbology. At the bottom of the window click Style then Save Style. Then save it as either a QML or and SLD. The QML is a little more complex.From an SLD copy the value in quotes after: quantity=From a QML copy the value in quotes after: value=
Note that this method also gives you the exact color that you have set.
-Thayer
Message: 1
Date: Mon, 1 Feb 2021 10:58:46 -0700
From: <upland at mcsnet.ca>
To: "QGIS mailing List" <Qgis-user at lists.osgeo.org>
Subject: [Qgis-user] Raster to Vector polygons
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Hello 

I've been trying to figure out a way to convert Raster slope catagories into
vector polygons.  I classify a raster surface model into slope classes
giving nice curvy polygons on the raster with the colors to differentiate
the different classes.  I've tried using the polygonize raster to vector but
it makes a whole bunch of square or rectangular polygons that don't match up
at all with my raster layer style.  I was hoping to find something that
would create polygons that are exactly reflective of what the raster looks
like with the classes and colors. Any ideas would be great.

Thank you

Normand 


  
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