Class: QgsRasterLayer

class qgis.core.QgsRasterLayer

Bases: QgsMapLayer, QgsAbstractProfileSource

Represents a raster layer.

A QgsRasterLayer is instantiated by specifying the name of a data provider, such as “gdal” or “wms”, and a url defining the specific data set to connect to. The raster layer constructor in turn instantiates a QgsRasterDataProvider subclass corresponding to the provider type, and passes it the url. The data provider connects to the data source.

Sample usage of the QgsRasterLayer class:

my_raster_layer = QgsRasterLayer("/path/to/file.tif", "my layer")

QgsRasterLayer() Constructor. Provider is not set.

QgsRasterLayer(uri: str, baseName: str = ‘’, providerType: str = ‘’, options: QgsRasterLayer.LayerOptions = QgsRasterLayer.LayerOptions()) This is the constructor for the RasterLayer class.

The main tasks carried out by the constructor are:

• Load the rasters default style (.qml) file if it exists

• Populate the RasterStatsVector with initial values for each band.

• Calculate the layer extents

• Determine whether the layer is gray, paletted or multiband.

• Assign sensible defaults for the red, green, blue and gray bands.

Enums

LayerType

alias of RasterLayerType

Methods

accept	param visitor:
appendError	Add error message
attributeTable	Returns the (possibly NULL) raster attribute table for the given band bandNumber.
attributeTableCount	Returns the number of attribute tables for the raster by counting the number of bands that have an associated attribute table.
bandCount	Returns the number of bands in this layer.
bandName	Returns the name of a band given its number.
brightnessFilter	Returns the raster's brightness/contrast filter.
canCreateRasterAttributeTable	Returns True if the raster renderer is suitable for creation of a raster attribute table.
childEvent
clone	Returns a new instance equivalent to this one.
connectNotify
constDataProvider	Returns the source data provider.
createMapRenderer	param rendererContext:
createProfileGenerator	param request:
customEvent
dataProvider	Returns the source data provider.
decodedSource	param source:
disconnectNotify
draw	This is an overloaded version of the draw() function that is called by both draw() and thumbnailAsPixmap
elevationProperties	rtype: QgsMapLayerElevationProperties
encodedSource	param source:
hasDependencyCycle	Checks whether a new set of dependencies will introduce a cycle this method is now deprecated and always return False, because circular dependencies are now correctly managed.
height	Returns the height of the (unclipped) raster.
htmlMetadata	rtype: str
hueSaturationFilter	Returns the raster's hue/saturation filter.
ignoreExtents	If the ignoreExtent flag is set, the layer will also render outside the bounding box reported by the data provider.
invalidateWgs84Extent	Invalidates the WGS84 extent.
isSignalConnected
isSpatial	rtype: bool
isValidRasterFileName	This helper checks to see whether the file name appears to be a valid raster file name.
lastModified	Returns time stamp for given file name
legendSymbologyItems	Returns a list with classification items (Text and color).
opacity	rtype: float
paletteAsPixmap	Returns a 100x100 pixmap of the color palette.
pipe	Returns the raster pipe.
previewAsImage	Draws a preview of the rasterlayer into a QImage
properties	rtype: Qgis.MapLayerProperties
providerType	[ data provider interface ] Which provider is being used for this Raster Layer?
rasterType	Returns the raster layer type (which is a read only property).
rasterUnitsPerPixelX	Returns the number of raster units per each raster pixel in X axis.
rasterUnitsPerPixelY	Returns the number of raster units per each raster pixel in Y axis.
readCommonStyle	Read style data common to all layer types
readCustomProperties	Read custom properties from project file.
readStyle	param node:
readStyleManager	Read style manager's configuration (if any).
readSymbology	param node:
readXml	param layer_node:
receivers
reload
renderer	Returns the raster's renderer.
resampleFilter	Returns the raster's resample filter.
resamplingStage	Returns which stage of the pipe should apply resampling.
sender
senderSignalIndex
setContrastEnhancement	Set contrast enhancement algorithm
setDataProvider	Set the data provider.
setDefaultContrastEnhancement	Sets the default contrast enhancement
setError	Sets error message
setExtent	Sets the extent
setLayerOrder	param layers:
setOpacity	param opacity:
setProviderType	Sets the providerType (provider key)
setRenderer	Sets the raster's renderer.
setResamplingStage	Select which stage of the pipe should apply resampling.
setSubLayerVisibility	param name:
setSubsetString	Sets the string (typically sql) used to define a subset of the layer
setTransformContext	Sets the coordinate transform context to transformContext
setValid	Sets whether layer is valid or not
showStatusMessage	param message:
subLayers	rtype: List[str]
subsetString	Returns the string (typically sql) used to define a subset of the layer.
temporalProperties	rtype: QgsMapLayerTemporalProperties
timerEvent
timestamp	rtype: QDateTime
width	Returns the width of the (unclipped) raster.
writeCommonStyle	Write style data common to all layer types
writeCustomProperties	Write custom properties to project file.
writeSld	Writes the symbology of the layer into the document provided in SLD 1.0.0 format
writeStyle	param node:
writeStyleManager	Write style manager's configuration (if exists).
writeSymbology	param a0:
writeXml	param layer_node:

Signals

subsetStringChanged

pyqtSignal(*types, name: str = ..., revision: int = ..., arguments: Sequence = ...) -> PYQT_SIGNAL

Attributes

MULTIPLE_BAND_MULTI_BYTE_ENHANCEMENT_ALGORITHM
MULTIPLE_BAND_MULTI_BYTE_MIN_MAX_LIMITS
MULTIPLE_BAND_SINGLE_BYTE_ENHANCEMENT_ALGORITHM
MULTIPLE_BAND_SINGLE_BYTE_MIN_MAX_LIMITS
SAMPLE_SIZE
SINGLE_BAND_ENHANCEMENT_ALGORITHM
SINGLE_BAND_MIN_MAX_LIMITS

class LayerOptions(loadDefaultStyle: bool = True, transformContext: QgsCoordinateTransformContext = QgsCoordinateTransformContext())

Bases: sip.wrapper

Constructor for LayerOptions.

QgsRasterLayer.LayerOptions(QgsRasterLayer.LayerOptions)

loadDefaultStyle

skipCrsValidation

transformContext

LayerType

alias of RasterLayerType

MULTIPLE_BAND_MULTI_BYTE_ENHANCEMENT_ALGORITHM = 1

MULTIPLE_BAND_MULTI_BYTE_MIN_MAX_LIMITS = 3

MULTIPLE_BAND_SINGLE_BYTE_ENHANCEMENT_ALGORITHM = 0

MULTIPLE_BAND_SINGLE_BYTE_MIN_MAX_LIMITS = 1

SAMPLE_SIZE = 250000.0

SINGLE_BAND_ENHANCEMENT_ALGORITHM = 1

SINGLE_BAND_MIN_MAX_LIMITS = 1

accept(self, visitor: QgsStyleEntityVisitorInterface) → bool

Parameters:

visitor (QgsStyleEntityVisitorInterface) –

Return type:

bool

appendError(self, error: QgsErrorMessage)

Add error message

attributeTable(self, bandNumber: int) → QgsRasterAttributeTable

Returns the (possibly NULL) raster attribute table for the given band bandNumber.

New in version 3.30.

Parameters:

bandNumber (int) –

Return type:

QgsRasterAttributeTable

attributeTableCount(self) → int

Returns the number of attribute tables for the raster by counting the number of bands that have an associated attribute table.

New in version 3.30.

Return type:

int

bandCount(self) → int

Returns the number of bands in this layer.

Return type:

int

bandName(self, bandNoInt: int) → str

Returns the name of a band given its number.

Parameters:

bandNoInt (int) –

Return type:

str

brightnessFilter(self) → QgsBrightnessContrastFilter

Returns the raster’s brightness/contrast filter.

See also

resampleFilter()

See also

hueSaturationFilter()

Return type:

QgsBrightnessContrastFilter

canCreateRasterAttributeTable(self) → bool

Returns True if the raster renderer is suitable for creation of a raster attribute table. The supported renderers are QgsPalettedRasterRenderer and QgsSingleBandPseudoColorRenderer.

New in version 3.30.

Return type:

bool

childEvent(self, QChildEvent)

clone(self) → QgsRasterLayer

Returns a new instance equivalent to this one. A new provider is created for the same data source and renderer is cloned too.

Return type:

QgsRasterLayer

Returns:

a new layer instance

New in version 3.0.

connectNotify(self, QMetaMethod)

constDataProvider(self) → QgsRasterDataProvider

Returns the source data provider.

This will be None if the layer is invalid.

Return type:

QgsRasterDataProvider

createMapRenderer(self, rendererContext: QgsRenderContext) → QgsMapLayerRenderer

Parameters:

rendererContext (QgsRenderContext) –

Return type:

QgsMapLayerRenderer

createProfileGenerator(self, request: QgsProfileRequest) → QgsAbstractProfileGenerator

Parameters:

request (QgsProfileRequest) –

Return type:

QgsAbstractProfileGenerator

customEvent(self, QEvent)

dataProvider(self) → QgsRasterDataProvider

Returns the source data provider.

This will be None if the layer is invalid.

Return type:

QgsRasterDataProvider

decodedSource(self, source: str, provider: str, context: QgsReadWriteContext) → str

Parameters:

• source (str) –

• provider (str) –

• context (QgsReadWriteContext) –

Return type:

str

disconnectNotify(self, QMetaMethod)

draw(self, theQPainter: QPainter, myRasterViewPort: QgsRasterViewPort, qgsMapToPixel: QgsMapToPixel = None)

This is an overloaded version of the draw() function that is called by both draw() and thumbnailAsPixmap

Parameters:

• theQPainter (QPainter) –

• myRasterViewPort (QgsRasterViewPort) –

• qgsMapToPixel (QgsMapToPixel = None) –

elevationProperties(self) → QgsMapLayerElevationProperties

Return type:

QgsMapLayerElevationProperties

encodedSource(self, source: str, context: QgsReadWriteContext) → str

Parameters:

• source (str) –

• context (QgsReadWriteContext) –

Return type:

str

hasDependencyCycle(self, Iterable[QgsMapLayerDependency]) → bool

Checks whether a new set of dependencies will introduce a cycle this method is now deprecated and always return False, because circular dependencies are now correctly managed.

Deprecated since version QGIS: 3.10

height(self) → int

Returns the height of the (unclipped) raster.

See also

width()

Return type:

int

htmlMetadata(self) → str

Return type:

str

hueSaturationFilter(self) → QgsHueSaturationFilter

Returns the raster’s hue/saturation filter.

See also

resampleFilter()

See also

brightnessFilter()

Return type:

QgsHueSaturationFilter

ignoreExtents(self) → bool

If the ignoreExtent flag is set, the layer will also render outside the bounding box reported by the data provider. To be used for example for WMS layers with labels or symbology that happens to be drawn outside the data extent.

New in version 3.10.

Return type:

bool

invalidateWgs84Extent(self)

Invalidates the WGS84 extent. If FlagTrustLayerMetadata is enabled, the extent is not invalidated because we want to trust metadata whatever happens.

New in version 3.20.

isSignalConnected(self, QMetaMethod) → bool

isSpatial(self) → bool

Return type:

bool

isValidRasterFileName(fileNameQString: str, retError: str) → bool

This helper checks to see whether the file name appears to be a valid raster file name. If the file name looks like it could be valid, but some sort of error occurs in processing the file, the error is returned in retError.

isValidRasterFileName(fileNameQString: str) -> bool

Parameters:

• fileNameQString (str) –

• retError (str) –

Return type:

bool

lastModified(name: str) → QDateTime

Returns time stamp for given file name

Parameters:

name (str) –

Return type:

QDateTime

legendSymbologyItems(self) → List[Tuple[str, QColor]]

Returns a list with classification items (Text and color).

Deprecated since version use: QgsRasterRenderer.createLegendNodes() instead.

Return type:

List[Tuple[str, QColor]]

opacity(self) → float

Return type:

float

paletteAsPixmap(self, bandNumber: int = 1) → QPixmap

Returns a 100x100 pixmap of the color palette. If the layer has no palette a white pixmap will be returned

Parameters:

bandNumber (int = 1) – the number of the band to use for generating a pixmap of the associated palette

Return type:

QPixmap

pipe(self) → QgsRasterPipe

Returns the raster pipe.

Return type:

QgsRasterPipe

previewAsImage(self, size: QSize, bgColor: QColor | Qt.GlobalColor | QGradient = Qt.white, format: QImage.Format = QImage.Format_ARGB32_Premultiplied) → QImage

Draws a preview of the rasterlayer into a QImage

New in version 2.4.

Parameters:

• size (QSize) –

• bgColor (Union[QColor) –

• format (QImage.Format = QImage.Format_ARGB32_Premultiplied) –

Return type:

QImage

properties(self) → Qgis.MapLayerProperties

Return type:

Qgis.MapLayerProperties

providerType(self) → str

[ data provider interface ] Which provider is being used for this Raster Layer?

Return type:

str

rasterType(self) → Qgis.RasterLayerType

Returns the raster layer type (which is a read only property).

Return type:

Qgis.RasterLayerType

rasterUnitsPerPixelX(self) → float

Returns the number of raster units per each raster pixel in X axis.

In a world file, this is normally the first row (without the sign). (E.g. the value reported by the GDAL geotransform[1]).

See also

rasterUnitsPerPixelY()

Return type:

float

rasterUnitsPerPixelY(self) → float

Returns the number of raster units per each raster pixel in Y axis.

In a world file, this is normally the first row (without the sign).

See also

rasterUnitsPerPixelX()

Return type:

float

readCommonStyle(self, layerElement: QDomElement, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Read style data common to all layer types

New in version 3.0.

readCustomProperties(self, layerNode: QDomNode, keyStartsWith: str = '')

Read custom properties from project file.

Parameters:

• layerNode – note to read from

• keyStartsWith – reads only properties starting with the specified string (or all if the string is empty)

readStyle(self, node: QDomNode, errorMessage: str, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Parameters:

• node (QDomNode) –

• errorMessage (str) –

• context (QgsReadWriteContext) –

• categories (Union[QgsMapLayer.StyleCategories) –

Return type:

bool

readStyleManager(self, layerNode: QDomNode)

Read style manager’s configuration (if any). To be called by subclasses.

readSymbology(self, node: QDomNode, errorMessage: str, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Parameters:

• node (QDomNode) –

• errorMessage (str) –

• context (QgsReadWriteContext) –

• categories (Union[QgsMapLayer.StyleCategories) –

Return type:

bool

readXml(self, layer_node: QDomNode, context: QgsReadWriteContext) → bool

Parameters:

• layer_node (QDomNode) –

• context (QgsReadWriteContext) –

Return type:

bool

receivers(self, PYQT_SIGNAL) → int

reload(self)

renderer(self) → QgsRasterRenderer

Returns the raster’s renderer.

See also

setRenderer()

Return type:

QgsRasterRenderer

resampleFilter(self) → QgsRasterResampleFilter

Returns the raster’s resample filter.

See also

brightnessFilter()

See also

hueSaturationFilter()

Return type:

QgsRasterResampleFilter

resamplingStage(self) → Qgis.RasterResamplingStage

Returns which stage of the pipe should apply resampling.

See also

QgsRasterPipe.resamplingStage()

New in version 3.16.

Return type:

Qgis.RasterResamplingStage

sender(self) → QObject

senderSignalIndex(self) → int

setContrastEnhancement(self, algorithm: QgsContrastEnhancement.ContrastEnhancementAlgorithm, limits: QgsRasterMinMaxOrigin.Limits = QgsRasterMinMaxOrigin.MinMax, extent: QgsRectangle = QgsRectangle(), sampleSize: int = QgsRasterLayer.SAMPLE_SIZE, generateLookupTableFlag: bool = True)

Set contrast enhancement algorithm

Parameters:

• algorithm (QgsContrastEnhancement.ContrastEnhancementAlgorithm) – Contrast enhancement algorithm

• limits (QgsRasterMinMaxOrigin.Limits = QgsRasterMinMaxOrigin.MinMax) – Limits

• extent (QgsRectangle = QgsRectangle()) – Extent used to calculate limits, if empty, use full layer extent

• sampleSize (int = QgsRasterLayer.SAMPLE_SIZE) – Size of data sample to calculate limits, if 0, use full resolution

• generateLookupTableFlag (bool = True) – Generate lookup table.

setDataProvider(self, provider: str)

Set the data provider.

Deprecated since version Use: the version with ProviderOptions instead.

setDataProvider(self, provider: str, options: QgsDataProvider.ProviderOptions, flags: Union[QgsDataProvider.ReadFlags, QgsDataProvider.ReadFlag] = QgsDataProvider.ReadFlags()) Set the data provider.

Parameters:

• provider (str) – provider key string, must match a valid QgsRasterDataProvider key. E.g. “gdal”, “wms”, etc.

• options – provider options

• flags – provider flags since QGIS 3.16

New in version 3.2.

setDefaultContrastEnhancement(self)

Sets the default contrast enhancement

setError(self, error: QgsError)

Sets error message

setExtent(self, rect: QgsRectangle)

Sets the extent

setLayerOrder(self, layers: Iterable[str])

Parameters:

layers (Iterable[str]) –

setOpacity(self, opacity: float)

Parameters:

opacity (float) –

setProviderType(self, providerType: str)

Sets the providerType (provider key)

setRenderer(self, renderer: QgsRasterRenderer)

Sets the raster’s renderer. Takes ownership of the renderer object.

See also

renderer()

Parameters:

renderer (QgsRasterRenderer) –

setResamplingStage(self, stage: Qgis.RasterResamplingStage)

Select which stage of the pipe should apply resampling.

See also

QgsRasterPipe.setResamplingStage()

New in version 3.16.

Parameters:

stage (Qgis.RasterResamplingStage) –

setSubLayerVisibility(self, name: str, vis: bool)

Parameters:

• name (str) –

• vis (bool) –

setSubsetString(self, subset: str) → bool

Sets the string (typically sql) used to define a subset of the layer

Parameters:

subset (str) – The subset string. This may be the where clause of a sql statement or other definition string specific to the underlying dataprovider and data store.

Return type:

bool

Returns:

True, when setting the subset string was successful, False otherwise

New in version 3.12.

setTransformContext(self, transformContext: QgsCoordinateTransformContext)

Sets the coordinate transform context to transformContext

New in version 3.8.

Parameters:

transformContext (QgsCoordinateTransformContext) –

setValid(self, valid: bool)

Sets whether layer is valid or not

showStatusMessage(self, message: str)

Parameters:

message (str) –

subLayers(self) → List[str]

Return type:

List[str]

subsetString(self) → str

Returns the string (typically sql) used to define a subset of the layer.

Return type:

str

Returns:

The subset string or null QString if not implemented by the provider

New in version 3.12.

subsetStringChanged

pyqtSignal(*types, name: str = …, revision: int = …, arguments: Sequence = …) -> PYQT_SIGNAL

types is normally a sequence of individual types. Each type is either a type object or a string that is the name of a C++ type. Alternatively each type could itself be a sequence of types each describing a different overloaded signal. name is the optional C++ name of the signal. If it is not specified then the name of the class attribute that is bound to the signal is used. revision is the optional revision of the signal that is exported to QML. If it is not specified then 0 is used. arguments is the optional sequence of the names of the signal’s arguments.

Parameters:

• name (str = ...) –

• revision (int = ...) –

• arguments (Sequence = ...) –

Return type:

PYQT_SIGNAL

temporalProperties(self) → QgsMapLayerTemporalProperties

Return type:

QgsMapLayerTemporalProperties

timerEvent(self, QTimerEvent)

timestamp(self) → QDateTime

Return type:

QDateTime

width(self) → int

Returns the width of the (unclipped) raster.

See also

height()

Return type:

int

writeCommonStyle(self, layerElement: QDomElement, document: QDomDocument, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Write style data common to all layer types

New in version 3.0.

writeCustomProperties(self, layerNode: QDomNode, doc: QDomDocument)

Write custom properties to project file.

writeSld(self, node: QDomNode, doc: QDomDocument, errorMessage: str, props: Dict[str, Any] = {}) → bool

Writes the symbology of the layer into the document provided in SLD 1.0.0 format

Parameters:

• node (QDomNode) – the node that will have the style element added to it.

• doc (QDomDocument) – the document that will have the QDomNode added.

• errorMessage (str) – reference to string that will be updated with any error messages

• props (Dict[str) – a open ended set of properties that can drive/inform the SLD encoding

Return type:

bool

Returns:

True in case of success

New in version 3.6.

writeStyle(self, node: QDomNode, doc: QDomDocument, errorMessage: str, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Parameters:

• node (QDomNode) –

• doc (QDomDocument) –

• errorMessage (str) –

• context (QgsReadWriteContext) –

• categories (Union[QgsMapLayer.StyleCategories) –

Return type:

bool

writeStyleManager(self, layerNode: QDomNode, doc: QDomDocument)

Write style manager’s configuration (if exists). To be called by subclasses.

writeSymbology(self, a0: QDomNode, doc: QDomDocument, errorMessage: str, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Parameters:

• a0 (QDomNode) –

• doc (QDomDocument) –

• errorMessage (str) –

• context (QgsReadWriteContext) –

• categories (Union[QgsMapLayer.StyleCategories) –

Return type:

bool

writeXml(self, layer_node: QDomNode, doc: QDomDocument, context: QgsReadWriteContext) → bool

Parameters:

• layer_node (QDomNode) –

• doc (QDomDocument) –

• context (QgsReadWriteContext) –

Return type:

bool