Linked Questions

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1answer
1k views

Multiple reclassification using RasterCalc in QGIS [duplicate]

Is there any way to perform multiple reclassification using RasterCalc? For example reclassifying value 1 to 100 in map Map can be written as: eq([Map]@1, 1, 100) But if there are multiple values ...
1
vote
1answer
168 views

Reclassifying raster analysis (like the one in ArcGIS Spatial Analyst) in QGIS [duplicate]

I am trying to reclassify raster (DEM) in QGIS. I know how it is done in ArcGIS (Spatial Analyst, reclassify option), but I would like to know how it is done in QGIS?. The point of my exercise is to ...
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0answers
40 views

No cell value in raster file [duplicate]

I downloaded a .tif raster file from opentopography.org. It's an Alos (AW3D30 ) topography file showing mountainous terrain in Sweden. On the very right the file contains terrain, and on the left a ...
8
votes
4answers
6k views

How to reclassify a float raster?

I have three rasters which represent distance (in metres) from certain things (bus stops, parks, libraries). I would like to reclassify these rasters so that they get integer values based on the ...
3
votes
2answers
11k views

How to reclass a raster with reclassify grid values in QGIS?

I'm new in QGIS and I'm trying to reclass a raster with reclassify grid values. I want to reclassify by table, however fixed table has only 3 rows and I need some more, but button to add is not ...
4
votes
2answers
5k views

How to classify/style rasters correctly?

I am using a GeoTiff raster data and trying to classify it. I was wondering what are the techniques that I can use in QGIS to do this? The raster I have looks like but I tried the reclassify tool ...
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2answers
2k views

Retrieving Elevation from Color in Raster DEM?

I'm fairly new to GIS work. I have a DEM in raster format, that is unfortunately not properly meta-referenced. In other words it has a legend where each color is assigned with the respective ...
1
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1answer
1k views

Export classified raster Class Values from DEM

I've classified an elevation raster into 4 classes. Is there a way to export these class values (0, 1, 2, 3) to a separate raster? I've tried exporting the raster to file, but this just gives the same ...
2
votes
1answer
3k views

How to replace the Nan or nodata values into 0? [duplicate]

I have a raster in .img format and i would trasform some values (Nan) into 0 with QGIS 2.14.3 (Windows). I've tried different ways but I didn't have results: 1- with raster --> conversion --> ...
0
votes
1answer
2k views

Classifying slope (flat, slope, steep, very steep) in QGIS? [duplicate]

I want to classify the slope of the DEM data, by dividing the slope by 4 classes: flat, ramps, steep, very steep. How to do this with QGIS?
2
votes
2answers
475 views

How to polygonise a large and detailed raster into a single valid polygon with QGIS?

I am doing research on the protected areas of the Amazon rainforest and I need to create a single polygon layer that has all the forested non-protected areas in one attribute row. I have tried using ...
2
votes
1answer
410 views

QGIS saving raster styles as vectors

I am using QGIS for analysis of aerial images. I have used the properties>style menu to create colour-banding for my raster map layer. This created 2 colour bands - but I want to convert these to ...
2
votes
1answer
772 views

Density slice/Colour slice in QGIS?

Can you do Raster Color Slices (like in ENVI) in QGIS? I.e. Where the histogram can be divided up into discrete units to represent different classes based on the values of the pixels.
4
votes
1answer
283 views

Cropping raster and merge it to overlapping DEM?

I am working with an existing DEM of a river and its surrounding area in QGIS (actually a virtual raster from four separate DEM TIF tiles). My goal is to add a bridge's profile to the DEM. I have a ...
1
vote
1answer
294 views

Draw a mask on a TIFF file

I have a raster (TIFF file) and I would like to draw a mask on it. So, I basically create a shapefile and draw polygons on the area I wanted to mask. Then, I would like to rasterize this shapefile by ...

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