Changing Raster Layer Style

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:''The raster layer properties are only to be used for displaying [[wikipedia:GDAL|GDAL]] raster files. They won't have any effect on GRASS raster maps. If you're working on  GRASS, see [[Displaying GRASS raster layers]].''
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The raster layer propertiers differ from the vector layer properties, due to the significant differences of the data.
 
The raster layer propertiers differ from the vector layer properties, due to the significant differences of the data.
 
You can open this dialog by double-clicking a raster layer in the [[Table of contents | TOC]] or right-clicking on the layer in the  [[Table of contents | TOC]] and choosing {{mitem|text=Properties}}.  
 
You can open this dialog by double-clicking a raster layer in the [[Table of contents | TOC]] or right-clicking on the layer in the  [[Table of contents | TOC]] and choosing {{mitem|text=Properties}}.  
  
[[File:Raster_properties.png|600 px|thumb|Raster layer properties in QGIS (on a LINUX [[Wiki:Operating system|OS]])|center]]
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==Render Type: Multiband color==
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#* True color (RGB=3,2,1) simulates the natural color.
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#* Standard false color (RGB=4,3,2) makes healthy vegetation generally appear red.
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#* False color (RGB=5,4,3 or 4,5,3) tends to distinguish different landcover material.
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# In the {{button|text=Layer stack}} pulldown-menu, select {{button|text=Yes}}.
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# Click the bottom {{button|text=...}} button to select directory and file name to save the result. You can skip this step if you only want to save the result temporarily.
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# Check the box {{button|text=Open output file after running algorithm}} (if not checked per default) and click {{button|text=Run}}. The resulting map should be added to the [[TOC]] automatically after the algorithm has finished, under the name ''Output layer''.
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# If necessary, you can rearrange the bands by opening the layer [[Exercise 01: First steps in QGIS|properties]] and selecting the {{button|text=Style}} tab. Adjust the bands as you see fit and confirm with {{button|text=Apply}} or {{button|text=OK}} ('''figure B''').
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#* For some color composites, (e.g. true color composites), the image may be enhanced by selecting {{button|text=Stretch to MinMax}} from the {{button|text=Contrast enhancement}} menu and selecting the {{button|text=Mean +/- standard deviation x}} radio button. After adjusting the standard deviation factor (a value between 1 and 2 should do), click {{button|text=Load}} and confirm with {{button|text=Apply}} or {{button|text=OK}}.
  
From top to bottom, you find the following options:
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[[Image:RemSens_Exercise03_2.png|thumb|center|450px|'''Figure B:''' The ''properties'' dialogue for a multiband raster layer in [[QGIS]] 2.0]]
# Symbology: here you can choose between two different ways of displaying the map:
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#* Single band gray: here you can choose between four sub-options:
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#** [[Grayscale]]
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#** [[Pseudocolor]]
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#** [[Freak out]]
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#** [[Color map]]
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#* [[Three band color]]
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# Transparency: set the [[raster transparency settings]]
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# Colormap: set the rules for the corresponding symbology (see above)
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# General: in this tab, information on the layer source, rows and columns, display, nodata value and the coordinate system is listed <br> Display name, coordinate system and visibility on different [[scale|scales]] can be [[scale dependent visibility|set]]
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# Metadata: this tab sums up any available information on the layer, e.g. driver, data type, origin and pixel size
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# Pyramids: this tab gives the possibility to build pyramids, which means creating lower resolution copies of the map, eventually increasing display  and navigation speed
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==Related articles==
 
* [[Vector layer properties]]
 
* [[Vector data]]
 
* [[Raster data]]
 
  
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==Render Type: Singleband gray==
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==Render Type: Singleband pseudocolor==
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==Set Transperancy==
  
 
[[category: Changing Raster Layer Symbology]]
 
[[category: Changing Raster Layer Symbology]]

Revision as of 15:35, 16 September 2014

The raster layer propertiers differ from the vector layer properties, due to the significant differences of the data. You can open this dialog by double-clicking a raster layer in the TOC or right-clicking on the layer in the TOC and choosing Properties.

Contents

Render Type: Multiband color

    • True color (RGB=3,2,1) simulates the natural color.
    • Standard false color (RGB=4,3,2) makes healthy vegetation generally appear red.
    • False color (RGB=5,4,3 or 4,5,3) tends to distinguish different landcover material.
  1. In the Layer stack pulldown-menu, select Yes.
  2. Click the bottom ... button to select directory and file name to save the result. You can skip this step if you only want to save the result temporarily.
  3. Check the box Open output file after running algorithm (if not checked per default) and click Run. The resulting map should be added to the TOC automatically after the algorithm has finished, under the name Output layer.
  4. If necessary, you can rearrange the bands by opening the layer properties and selecting the Style tab. Adjust the bands as you see fit and confirm with Apply or OK (figure B).
    • For some color composites, (e.g. true color composites), the image may be enhanced by selecting Stretch to MinMax from the Contrast enhancement menu and selecting the Mean +/- standard deviation x radio button. After adjusting the standard deviation factor (a value between 1 and 2 should do), click Load and confirm with Apply or OK.
Figure B: The properties dialogue for a multiband raster layer in QGIS 2.0


Render Type: Singleband gray

Render Type: Singleband pseudocolor

Set Transperancy

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