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BaseStretchRenderer QML Type

A base class for stretch raster renderers. More...

Import Statement: import Esri.ArcGISRuntime 100.6
Since: Esri.ArcGISRuntime 100.0
Inherits:

RasterRenderer

Inherited By:

RGBRenderer and StretchRenderer

Properties

Signals

Detailed Description

A base class for stretch renderers that can help visualize raster data using RasterLayer.

Stretching improves the appearance of the raster data by spreading its pixel values along a histogram whose minimum and maximum values are defined by the raster's bit depth. For example, an 8-bit raster dataset will be stretched along a histogram from 0 to 255.

Utilize the different stretch types by using the different StretchParameters classes:

For detailed information on the different stretch types, please consult the ArcGIS Desktop documentation.

Note: You cannot declare or create a component of this type in QML code.

Note: This type is immutable once created. Once the renderer is created and applied to a layer, none of its properties can be changed. Instead, create a new renderer and apply it to the layer.

This QML type supports the following default properties. A default property may be declared inside another declared object without being assigned explicitly to a property.

TypeDefault Property
StretchParametersstretchParameters

Property Documentation

estimateStatistics : bool

Whether statistics should be estimated for the raster dataset.

This is typically needed for datasets that do not have statistics.


gammas : list<double>

A list of values in the range 0-2 to apply gamma correction for each band in the raster dataset.

Gammas specifies a list of values in the range 0-2 to apply gamma correction for each band in the raster dataset. Gamma refers to the degree of contrast between the mid-level gray values of a raster dataset. Gamma does not affect the black or white values in a raster dataset, only the middle values. By applying a gamma correction, you can control the overall brightness of a raster dataset. Additionally, gamma changes not only the brightness but also the ratios of red to green to blue. Values lower than 1 decrease the contrast in the darker areas and increase the contrast in the lighter areas. This darkens the image without saturating the dark or light areas of the image. This helps bring out details in lighter features, such as building tops. Conversely, gamma values greater than 1 increase the contrast in darker areas, such as shadows from buildings. Gamma values greater than one can also help bring out details in lower elevation areas when working with elevation data.


[default] stretchParameters : StretchParameters

The StretchParameters to use for this StretchRenderer.


Signal Documentation

estimateStatisticsChanged()

Emitted when the estimateStatistics property changes.


gammasChanged()

Emitted when the gammas property changes.


stretchParametersChanged()

Emitted when the stretchParameters property changes.



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