====== Raster Visualisation ======

The legend tools of Orbit GIS can also be used to specify how you want a raster to be rendered.  These tools are only enabled for single-band images because Orbit GIS only considers those to be rasters (this may change as Orbit GIS evolves in upcoming versions).

Legend options for Rasters are limited to :
  * Basic Appearance 
  * [[orbitgis:datasets:propreties:legend:old:legend_classificationpanel|Classification]] (of sample values)

===== Basic Appearance =====

The basic appearance tab allows you to modify basic image rendering parameters.


{{rap_legend_basicappearance.png|:extensions:rasterprocessing:rap_legend_basicappearance.png}}

==== Color & Grayscale Images ====

These are editors for generic image rendering parameters.

FIXME Refer to the orbitgis documentation about these parameters once it's ready.


==== Raster Image ====

A raster may contain specific samples that are of no real value but rather indicate the given sample is to be ignored.

Orbit GIS allows you to configure a sample value that's to be considered "background" or a sample value that's to be considered "missing".  When configured, these values will not be used when Orbit GIS creates a histogram.

<note important>The missing values will only be used from the moment they are saved in the legend file.\\ Please press the "save" button in the toolbar before proceeding.</note>


===== Classification =====

The "Classification" tab is only enabled when a raster image is selected.  

The only classification that can be made is one that classifies the "SampleValue" attribute to a "Thematic Color" parameter which is then used to render the raster.

{{rap_legend_classification.png|:extensions:rasterprocessing:rap_legend_classification.png}}

==== Classification Auto Fill-In ====

Once mappings have been generated, the "Auto Fill-In" utility can be used to apply a gradient or palette to the mappings table.

{{rap_autofillin.png|:extensions:rasterprocessing:rap_autofillin.png}}