A base class for stretch raster renderers. More...
| Header: | #include <BaseStretchRenderer.h> |
| Since: | Esri::ArcGISRuntime 100.0 |
| Inherits: | Esri::ArcGISRuntime::RasterRenderer |
| Inherited By: | Esri::ArcGISRuntime::RGBRenderer and Esri::ArcGISRuntime::StretchRenderer |
This class was introduced in Esri::ArcGISRuntime 100.0.
Public Functions
| virtual | ~BaseStretchRenderer() override |
| QList<double> | gammas() const |
| bool | isEstimateStatistics() const |
| Esri::ArcGISRuntime::StretchParameters | stretchParameters() const |
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:
- HistogramEqualizationStretchParameters
- MinMaxStretchParameters
- PercentClipStretchParameters
- StandardDeviationStretchParameters
For detailed information on the different stretch types, please consult the ArcGIS Desktop documentation.
Member Function Documentation
[override virtual] BaseStretchRenderer::~BaseStretchRenderer ()
Destructor.
QList<double> BaseStretchRenderer::gammas() const
Returns the gamma values.
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.
bool BaseStretchRenderer::isEstimateStatistics () const
Returns whether statistics should be estimated for the raster dataset.
This is typically needed for datasets that do not have statistics.
Esri::ArcGISRuntime::StretchParameters BaseStretchRenderer::stretchParameters () const
Returns the StretchParameters to use for this StretchRenderer.