You can add raster data stored on your device or raster data from an image service by performing one of the following tasks:
- Adding a raster to a map or scene using a raster layer if you want to display the raster
- Adding a raster to a map or scene for use with a raster function
Raster data provides a unique way to analyze and visualize geographic phenomena. Rasters consist of a matrix of cells, with each cell containing a value. Rasters can have multiple dimensions or bands, for example, the red, green, and blue channels in an aerial photo. Rasters are different from vectors, which use points, lines, and polygons to represent features. For more information on raster data, including advantages and disadvantages of using it, see What is raster data? and Imagery and raster in ArcGIS Pro in the ArcGIS Desktop help.
Raster data is represented by the Raster
class. Your ArcGIS Runtime app can work with many sources of raster data including raster files, mosaic datasets, raster data shared through image services, or the results of raster functions. A raster function can take any of these rasters as input for analysis.
The Raster object implements the loadable pattern described in Loading resources asynchronously and asynchronously accesses raster data from remote services or datasets.
Raster data supports the identify operation to obtain Raster
values when a user clicks on a pixel in a Map
or Scene
for Raster
.
Create a raster from a raster file
To add raster files stored on your desktop or device to your app, create a Raster
object using the path of the raster file.
Raster* raster = new Raster(m_localRasterFilePath, this);
Load a raster from a GeoPackage
A GeoPackage is an open, standards-based, platform-independent, portable, self-describing, compact format for transferring geospatial information. It is a platform-independent SQLite database file that contains data and metadata tables. For details, refer to the OGC GeoPackage specification. Using ArcGIS Runtime SDK, you can read a local GeoPackage and load the feature tables and rasters it contains.
Open a Geo
using the path to the .gpkg
file. The Geo
property returns a collection of all rasters in the package. You can work with a Geo
as you would any other Raster
, including adding it as a Raster
to your app's map.
Create a raster from a mobile mosaic dataset
Raster data stored in a mobile mosaic dataset should be read through the Mosaic
, which inherits from Raster
. The Mosaic
object is instantiated with a path of the mobile geodatabase and a name of the dataset.
MosaicDatasetRaster* mosaicDatasetRaster = new MosaicDatasetRaster(m_localMdsSqliteFilePath, m_localMdsTableName, this);
Create a mobile mosaic dataset and add raster files
Mosaic
can also be used to create a mobile mosaic dataset in a new mobile geodatabase and save it to the device. After the mobile mosaic dataset is created, individual raster files can be asynchronously added to it. The mobile geodatabase is created when the Mosaic
is loaded successfully.
QString gdbFilePath = QDir::toNativeSeparators(QDir::homePath() + m_geodatabase);
m_mosaicDatasetRaster = MosaicDatasetRaster::create(gdbFilePath, m_tableName, SpatialReference::webMercator());
connect(m_mosaicDatasetRaster, &MosaicDatasetRaster::loadStatusChanged, this, [this](LoadStatus loadStatus)
{
if (loadStatus == LoadStatus::Loaded)
{
AddRastersParameters m_addRastersParameters;
m_addRastersParameters.setInputDirectory(QDir::toNativeSeparators(QDir::homePath() + m_inputDirectoryUrl));
m_addRastersParameters.setFilter("tif$"); // Regex filter
m_mosaicDatasetRaster->addRasters(m_addRastersParameters);
}
});
connect(m_mosaicDatasetRaster, &MosaicDatasetRaster::addRastersCompleted, this, [this](QUuid taskId, Error error)
{
Q_UNUSED(taskId)
if (error.isEmpty())
{
m_rasterLayer = new RasterLayer(m_mosaicDatasetRaster);
m_map->operationalLayers()->append(m_rasterLayer);
}
});
m_mosaicDatasetRaster->load();
MosaicDatasetRaster {
id: mdsRaster
onComponentCompleted: {
createWithPath(System.temporaryFolder.url + "/NewMosaicDataSet.geodatabase",
"rasterCollection", SpatialReference.createWebMercator());
addRasters(addRasterParams);
}
}
// add a mapView component
MapView {
id: mapView
anchors.fill: parent
focus: true
Map {
BasemapLightGrayCanvas {}
RasterLayer {
id: rasterLayer
raster: mdsRaster
visible: true
}
}
}
Use the Add
class to perform tasks, such as the following:
- Set the input directory containing the raster files to be added
- Control other properties of the mosaic, such as minimum and maximum pixel sizes
Create a raster from an image service
Raster and image data can be shared as an image service using ArcGIS Server. An image service provides access to raster data through a web service. A single raster dataset or a mosaic dataset that contains a collection of raster datasets can be served as one image service. The mosaic dataset can dynamically process and mosaic the images on the fly. An image service supports accessing both the mosaicked image and its catalog, as well as individual rasters in the catalog. For more information on image services, see Key concepts for image services in the ArcGIS help.
Use the Image
class to work with image services in your ArcGIS Runtime app. You can create an Image
with the URL of an image service. And if you want to display the raster data on a map, create a raster layer for it.
For mosaicked images, a mosaic rule defines how the individual rasters are combined. You can use the default rule defined with the service or, starting with 100.9.0, define rule settings to control how overlapping areas in the mosaic are handled. In addition to how it's displayed, the mosaic rule may effect values returned when identifying, computing a histogram, or exporting the image.
Image
is a subclass of Raster
, so any operation that can be applied to the Raster class, such as raster functions, can also be applied to Image
. Besides the common properties inherited from the Raster
class, Image
has additional properties and capabilities, such as the image service metadata and rendering rules. After the image service raster has been loaded, the metadata of the image service can be retrieved through the service info property, which is represented by ArcGIS
. However, only a subset of the metadata, including attribution text and a list of information on predefined service rendering rules, is exposed in ArcGIS Runtime. For more information on the metadata of an image service, see Image Service in the ArcGIS services reference.
ImageServiceRaster* imageServiceRaster = new ImageServiceRaster(m_imageServiceUrl, this);
if (imageServiceRaster)
{
connect(imageServiceRaster, &ImageServiceRaster::doneLoading, this, [this, imageServiceRaster]()
{
RasterLayer* rasterLayer = new RasterLayer(imageServiceRaster, this);
if (rasterLayer)
{
connect(rasterLayer, &RasterLayer::doneLoading, this, [this, rasterLayer]()
{
m_mapFromService->operationalLayers()->clear();
m_mapFromService->operationalLayers()->append(rasterLayer);
resetMap(m_mapFromService);
});
rasterLayer->load();
}
});
imageServiceRaster->load();
}
Create a raster from a raster function
Raster functions can be applied to a raster to process that data. This processing is not permanently applied to the data; instead, it is applied on the fly as the rasters are accessed.
ArcGIS Runtime supports a subset of raster functions.
The code below gives an example of how to create a raster from a raster function.
RasterFunction* rasterFunction = new RasterFunction(m_dataPath + "/hillshade_simplified.json", this);
RasterFunctionArguments* arguments = rasterFunction->arguments();
arguments->setRaster("raster", m_imageServiceRaster);
// create a new raster with the raster function and add to the operational layer
Raster* raster = new Raster(rasterFunction, this);
RasterLayer* rasterLayer = new RasterLayer(raster, this);
Raster functions supported by ArcGIS Runtime
ArcGIS Runtime supports a subset of raster functions supported. The raster functions supported by ArcGIS Runtime are provided in this section, along with the syntax for using them. The syntax is close to the ArcGIS REST syntax for the same functions but is not exactly the same.
The general syntax for ArcGIS Runtime raster functions is the following:
{
"raster_function":{"type":"<Raster Function Name>"},
"raster_function_arguments":
{
"argument1":"<JSON Value Object>",
"argument2":"<JSON Value Object>",
"argumentN":"<JSON Value Object>",
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Clip
{
"raster_function":{"type":"Clip_function"},
"raster_function_arguments":
{
"minx":{"double":value,"type":"Raster_function_variable"},
"miny":{"double":value,"type":"Raster_function_variable"},
"maxx":{"double":value,"type":"Raster_function_variable"},
"maxy":{"double":value,"type":"Raster_function_variable"},
"dx":{"double":cell_size_x,"type":"Raster_function_variable"},
"dy":{"double":cell_size_y,"type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Colormap
{
"raster_function":{"type":"Colormap_function"},
"raster_function_arguments":
{
"raster_colormap":{"colors":[color1,color2,...,colorN],"type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Colormap_to_RGB
{
"raster_function":{"type":"Colormap_to_RGB_function"},
"raster_function_arguments":
{
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Color_ramp
{
"raster_function":{"type":"Color_ramp_function"},
"raster_function_arguments":
{
"resizable":{"bool":false,"type":"Raster_function_variable"},
"color_ramp":
{
"color_ramp":
{
"ramps":
[
{"to_color":[0,255,0],"from_color":[0,191,191],"num_colors":3932,"type":"Algorithmic_color_ramp","algorithmic_type":"hsv"},
{"to_color":[255,255,0],"from_color":[0,255,0],"num_colors":3932,"type":"Algorithmic_color_ramp","algorithmic_type":"hsv"},
{"to_color":[255,127,0],"from_color":[255,255,0],"num_colors":3932,"type":"Algorithmic_color_ramp","algorithmic_type":"hsv"},
{"to_color":[191,127,63],"from_color":[255,127,0],"num_colors":3932,"type":"Algorithmic_color_ramp","algorithmic_type":"hsv"},
{"to_color":[20,20,20],"from_color":[191,127,63],"num_colors":3935,"type":"Algorithmic_color_ramp","algorithmic_type":"hsv"}
],
"type":"Multipart_color_ramp"
},
"type":"Raster_function_variable"
},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Composite_band
{
"raster_function":{"type":"Composite_band_function"},
"raster_function_arguments":
{
"raster_names":{"name":"raster_names","string_array":["r1","r2","r3","r4"],"type":"Raster_function_variable"},
"r1":{"name":"r1","is_raster":true,"type":"Raster_function_variable"},
"r2":{"name":"r2","is_raster":true,"type":"Raster_function_variable"},
"r3":{"name":"r3","is_raster":true,"type":"Raster_function_variable"},
"r4":{"name":"r4","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Extract_band
{
"raster_function":{"type":"Extract_band_function"},
"raster_function_arguments":
{
"exact_match":{"bool":false,"type":"Raster_function_variable"},
"band_indexes":{"int_array":[2,1,0],"type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Geometric
{
"raster_function":{"type":"Geometric_function"},
"raster_function_arguments":
{
"raster_transform":{"raster_transform":"Raster Transform JSON object","type":"Raster_function_variable"},
"z_offset":{"double":0,"type":"Raster_function_variable"},
"z_factor":{"double":1,"type":"Raster_function_variable"},
"raster":{"is_raster":true,"name":"raster","type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Hillshade
{
"raster_function":{"type":"Hillshade_function"},
"raster_function_arguments":
{
"z_factor":{"double":0.0002,"type":"Raster_function_variable"},
"slope_type":{"raster_slope_type":"none","type":"Raster_function_variable"},
"azimuth":{"double":315,"type":"Raster_function_variable"},
"altitude":{"double":45,"type":"Raster_function_variable"},
"nbits":{"int":8,"type":"Raster_function_variable"}, // Number of bits per pixel for output raster
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Mask
{
"raster_function":{"type":"Mask_function"},
"raster_function_arguments":
{
"nodata_values":{"double_array":[value1, value2, ..., valueN],"type":"Raster_function_variable"},
"nodata_interpretation":{"nodata_interpretation":"all","type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Pansharpen
{
"raster_function":{"type":"Pansharpen_function"},
"raster_function_arguments":
{
"weights":{"double_array":[0.10000000000000001,0.5,0.40000000000000002,0.29999999999999999],"type":"Raster_function_variable"},
"pansharpen_type":{"pansharpen_type":"gram_schmidt","type":"Raster_function_variable"},
"pan_raster":{"name":"pan_raster","is_raster":true,"type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Raster_calculator
{
"raster_function":{"type":"Raster_calculator_function"},
"raster_function_arguments":
{
"expression":{"string":"r1 + r2","name":"expression","type":"Raster_function_variable"},
"raster_names":{"name":"raster_names","type":"Raster_function_variable"},
"raster_names":{"name":"raster_names","string_array":["r1","r2"],"type":"Raster_function_variable"},
"r1":{"name":"r1","is_raster":true,"type":"Raster_function_variable"},
"r2":{"name":"r2","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Stretch
{
"raster_function":{"type":"Stretch_function"},
"raster_function_arguments":
{
"stretch_type":{"raster_stretch_type":"minimum_maximum","type":"Raster_function_variable"},
"min_values":{"double_array":[-10977],"type":"Raster_function_variable"},
"max_values":{"double_array":[8685],"type":"Raster_function_variable"},
"estimate_stats":{"bool":false,"type":"Raster_function_variable"},
"raster":{"name":"raster","is_raster":true,"type":"Raster_function_variable"},
"type":"Raster_function_arguments"
},
"type":"Raster_function_template"
}
Add a raster using a raster layer
It's not necessary to display the raster data you work with in your app. However, if you want your users to view raster data on a map, add the raster using the Raster
class. Raster
can render raster data from any type of raster. See Layers for more information about creating and working with raster layers.
You can add a raster layer to a map as either a basemap or an operational layer. When adding a raster layer as an operational layer to a map with different spatial reference, the layer will be reprojected on the fly and added to the map.
You can also change the renderer to control how the data is visualized on the map.
See Layers for more information about creating and working with raster layers.
Supported raster formats
ArcGIS Runtime supports a subset of raster file formats that ArcGIS Desktop supports. The raster file formats ArcGIS Runtime supports include the following:
- ASRP/USRP
- CRF
- DTED0, 1, 2
- GeoTIFF
- HFA
- HRE
- IMG
- JPEG
- JPEG 2000
- MrSID, generations 2, 3, and 4
- NITF
- PNG
- RPF (CIB)
- RPF (CADRG)
- SRTM1, 2
- Mobile mosaic datasets