Class: QgsRasterInterface¶

Base class for processing filters like renderers, reprojector, resampler etc.

Note

This is an abstract class, with methods which must be implemented by a subclass.

The following methods must be implemented: bandCount(), block(), clone(), dataType()

Class Hierarchy¶

Subclasses¶

`QgsBrightnessContrastFilter`	Brightness/contrast and gamma correction filter pipe for rasters.
`QgsRasterRenderer`	Raster renderer pipe that applies colors to a raster.
`QgsHueSaturationFilter`	Color and saturation filter pipe for rasters.
`QgsRasterDataProvider`	Base class for raster data providers.
`QgsRasterNuller`	Raster pipe that deals with null values.
`QgsRasterProjector`	Implements approximate projection support for optimised raster transformation.
`QgsRasterResampleFilter`	Resample filter pipe for rasters.

Enums

Capability

alias of RasterInterfaceCapability

Abstract Methods

`bandCount`	Gets number of bands
`block`	Read block of data using given extent and size.
`clone`	Clone itself, create deep copy
`dataType`	Returns data type for the band specified by number

Methods

`bandStatistics`	Returns the band statistics.
`capabilitiesString`	Returns the raster interface capabilities in friendly format.
`dataTypeSize`	Returns the size (in bytes) for the data type for the specified band.
`displayBandName`	Generates a friendly, descriptive name for the specified bandNumber.
`hasStatistics`	Returns `True` if histogram is available (cached, already calculated).
`initHistogram`	Fill in histogram defaults if not specified
`initStatistics`	Fill in statistics defaults if not specified

Virtual Methods

In PyQGIS, only methods marked as virtual can be safely overridden in a Python subclass of QgsRasterInterface. See the FAQ for more details.

`capabilities`	Returns the capabilities supported by the interface.
`colorInterpretationName`	Returns the name of the color interpretation for the specified bandNumber.
`cumulativeCut`	Find values for cumulative pixel count cut.
`extent`	Gets the extent of the interface.
`generateBandName`	helper function to create zero padded band names
`hasHistogram`	Returns `True` if histogram is available (cached, already calculated)
`histogram`	Returns a band histogram.
`input`	Current input
`on`	Returns whether the interface is on or off
`readXml`	Sets base class members from xml.
`setInput`	Set input.
`setOn`	Sets whether the interface is on or off
`sourceDataType`	Returns source data type for the band specified by number, source data type may be shorter than dataType
`sourceInput`	Gets source / raw input, the first in pipe, usually provider.
`writeXml`	Write base class members to xml.
`xBlockSize`	Gets block size
`xSize`	Gets raster size
`yBlockSize`
`ySize`

class qgis.core.QgsRasterInterface[source]¶

Bases: object

Capability¶: alias of RasterInterfaceCapability

abstract bandCount(self) → int[source]¶

Gets number of bands

Return type:: int

bandStatistics(self, bandNo: int, stats: int, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0, feedback: QgsRasterBlockFeedback | None = None) → QgsRasterBandStats[source]¶

Returns the band statistics.

Parameters:

bandNo (int) – The band (number).
stats (int) – Requested statistics
extent (QgsRectangle = QgsRectangle()) – Extent used to calc statistics, if empty, whole raster extent is used.
sampleSize (int = 0) – Approximate number of cells in sample. If 0, all cells (whole raster will be used). If raster does not have exact size (WCS without exact size for example), provider decides size of sample.
feedback (Optional[QgsRasterBlockFeedback] = None) – optional feedback object

Deprecated since version 3.40: Use Qgis.RasterBandStatistic instead of int for stats argument.

Return type:: QgsRasterBandStats

bandStatistics(self, bandNo: int, stats: Qgis.RasterBandStatistics | Qgis.RasterBandStatistic = Qgis.RasterBandStatistic.All, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0, feedback: QgsRasterBlockFeedback | None = None) → QgsRasterBandStats[source]

Returns the band statistics.

Parameters:

bandNo (int) – The band (number).
stats (Union[Qgis.RasterBandStatistics, Qgis.RasterBandStatistic] = Qgis.RasterBandStatistic.All) – Requested statistics
extent (QgsRectangle = QgsRectangle()) – Extent used to calc statistics, if empty, whole raster extent is used.
sampleSize (int = 0) – Approximate number of cells in sample. If 0, all cells (whole raster will be used). If raster does not have exact size (WCS without exact size for example), provider decides size of sample.
feedback (Optional[QgsRasterBlockFeedback] = None) – optional feedback object

Return type:

QgsRasterBandStats

abstract block(self, bandNo: int, extent: QgsRectangle, width: int, height: int, feedback: QgsRasterBlockFeedback | None = None) → QgsRasterBlock | None[source]¶

Read block of data using given extent and size. Returns pointer to data. Caller is responsible to free the memory returned.

Parameters:

bandNo (int) – band number
extent (QgsRectangle) – extent of block
width (int) – pixel width of block
height (int) – pixel height of block
feedback (Optional[QgsRasterBlockFeedback] = None) – optional raster feedback object for cancellation/preview. Added in QGIS 3.0.

Return type:

Optional[QgsRasterBlock]

virtual capabilities(self) → Qgis.RasterInterfaceCapabilities[source]¶

Returns the capabilities supported by the interface.

Return type:: Qgis.RasterInterfaceCapabilities

capabilitiesString(self) → str[source]¶

Returns the raster interface capabilities in friendly format.

Deprecated since version 3.40: Will be removed in QGIS 4.0.

Return type:: str

abstract clone(self) → QgsRasterInterface | None[source]¶

Clone itself, create deep copy

Return type:: Optional[QgsRasterInterface]

virtual colorInterpretationName(self, bandNumber: int) → str[source]¶

Returns the name of the color interpretation for the specified bandNumber. It is translated since QGIS 3.40

Added in version 3.18.

Parameters:: bandNumber (int)
Return type:: str

virtual cumulativeCut(self, bandNo: int, lowerCount: float, upperCount: float, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0)[source]¶

Find values for cumulative pixel count cut.

Parameters:

bandNo (int) – The band (number).
lowerCount (float) – The lower count as fraction of 1, e.g. 0.02 = 2%
upperCount (float) – The upper count as fraction of 1, e.g. 0.98 = 98%
lowerValue – Location into which the lower value will be set.
upperValue – Location into which the upper value will be set.
extent (QgsRectangle = QgsRectangle()) – Extent used to calc histogram, if empty, whole raster extent is used.
sampleSize (int = 0) -> (float) – Approximate number of cells in sample. If 0, all cells (whole raster will be used). If raster does not have exact size (WCS without exact size for example), provider decides size of sample.

abstract dataType(self, bandNo: int) → Qgis.DataType[source]¶

Returns data type for the band specified by number

Parameters:: bandNo (int)
Return type:: Qgis.DataType

dataTypeSize(self, bandNo: int) → int[source]¶

Returns the size (in bytes) for the data type for the specified band.

Parameters:: bandNo (int)
Return type:: int

displayBandName(self, bandNumber: int) → str[source]¶

Generates a friendly, descriptive name for the specified bandNumber.

Added in version 3.18.

Parameters:: bandNumber (int)
Return type:: str

virtual extent(self) → QgsRectangle[source]¶

Gets the extent of the interface.

Return type:: QgsRectangle
Returns:: QgsRectangle containing the extent of the layer

virtual generateBandName(self, bandNumber: int) → str[source]¶

helper function to create zero padded band names

Parameters:: bandNumber (int)
Return type:: str

virtual hasHistogram(self, bandNo: int, binCount: int, minimum: Any = Py_None, maximum: Any = Py_None, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0, includeOutOfRange: bool = False) → bool[source]¶

Returns True if histogram is available (cached, already calculated)

Note

the parameters are the same as in histogram()

Parameters:

bandNo (int)
binCount (int)
minimum (Any = Py_None)
maximum (Any = Py_None)
extent (QgsRectangle = QgsRectangle())
sampleSize (int = 0)
includeOutOfRange (bool = False)

Return type:

bool

hasStatistics(self, bandNo: int, stats: int, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0) → bool[source]¶

Returns True if histogram is available (cached, already calculated). The parameters are the same as in bandStatistics()

Return type:: bool
Returns:: True if statistics are available (ready to use)

Deprecated since version 3.40: Use Qgis.RasterBandStatistic instead of int for stats argument.

Parameters:

bandNo (int)
stats (int)
extent (QgsRectangle = QgsRectangle())
sampleSize (int = 0)

hasStatistics(self, bandNo: int, stats: Qgis.RasterBandStatistics | Qgis.RasterBandStatistic = Qgis.RasterBandStatistic.All, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0) → bool[source]

Returns True if histogram is available (cached, already calculated). The parameters are the same as in bandStatistics()

Return type:

bool

Returns:

True if statistics are available (ready to use)

Parameters:

bandNo (int)
stats (Union[Qgis.RasterBandStatistics, Qgis.RasterBandStatistic] = Qgis.RasterBandStatistic.All)
extent (QgsRectangle = QgsRectangle())
sampleSize (int = 0)

virtual histogram(self, bandNo: int, binCount: int = 0, minimum: Any = Py_None, maximum: Any = Py_None, extent: QgsRectangle = QgsRectangle(), sampleSize: int = 0, includeOutOfRange: bool = False, feedback: QgsRasterBlockFeedback | None = None) → QgsRasterHistogram[source]¶

Returns a band histogram. Histograms are cached in providers.

Parameters:

bandNo (int) – The band (number).
binCount (int = 0) – Number of bins (intervals,buckets). If 0, the number of bins is decided automatically according to data type, raster size etc.
minimum (Any = Py_None) – Minimum value, if NaN (None for Python), raster minimum value will be used.
maximum (Any = Py_None) – Maximum value, if NaN (None for Python), raster maximum value will be used.
extent (QgsRectangle = QgsRectangle()) – Extent used to calc histogram, if empty, whole raster extent is used.
sampleSize (int = 0) – Approximate number of cells in sample. If 0, all cells (whole raster will be used). If raster does not have exact size (WCS without exact size for example), provider decides size of sample.
includeOutOfRange (bool = False) – include out of range values
feedback (Optional[QgsRasterBlockFeedback] = None) – optional feedback object

Return type:

QgsRasterHistogram

Returns:

Vector of non NULL cell counts for each bin.

Note

binCount, minimum and maximum not optional in Python bindings

initHistogram(self, histogram: QgsRasterHistogram, bandNo: int, binCount: int, minimum: Any = Py_None, maximum: Any = Py_None, boundingBox: QgsRectangle = QgsRectangle(), sampleSize: int = 0, includeOutOfRange: bool = False)[source]¶

Fill in histogram defaults if not specified

Note

the parameters are the same as in histogram()

Parameters:

histogram (QgsRasterHistogram)
bandNo (int)
binCount (int)
minimum (Any = Py_None)
maximum (Any = Py_None)
boundingBox (QgsRectangle = QgsRectangle())
sampleSize (int = 0)
includeOutOfRange (bool = False)

initStatistics(self, statistics: QgsRasterBandStats, bandNo: int, stats: int, boundingBox: QgsRectangle = QgsRectangle(), binCount: int = 0)[source]¶

Fill in statistics defaults if not specified

Deprecated since version 3.40: Use Qgis.RasterBandStatistic instead of int for stats argument.

Parameters:

statistics (QgsRasterBandStats)
bandNo (int)
stats (int)
boundingBox (QgsRectangle = QgsRectangle())
binCount (int = 0)

initStatistics(self, statistics: QgsRasterBandStats, bandNo: int, stats: Qgis.RasterBandStatistics | Qgis.RasterBandStatistic = Qgis.RasterBandStatistic.All, boundingBox: QgsRectangle = QgsRectangle(), binCount: int = 0)[source]

Fill in statistics defaults if not specified

Parameters:

statistics (QgsRasterBandStats)
bandNo (int)
stats (Union[Qgis.RasterBandStatistics, Qgis.RasterBandStatistic] = Qgis.RasterBandStatistic.All)
boundingBox (QgsRectangle = QgsRectangle())
binCount (int = 0)

virtual input(self) → QgsRasterInterface | None[source]¶

Current input

Return type:: Optional[QgsRasterInterface]

virtual on(self) → bool[source]¶

Returns whether the interface is on or off

Return type:: bool

virtual readXml(self, filterElem: QDomElement)[source]¶

Sets base class members from xml. Usually called from create() methods of subclasses

Parameters:: filterElem (QDomElement)

virtual setInput(self, input: QgsRasterInterface | None) → bool[source]¶

Set input. Returns True if set correctly, False if cannot use that input

Parameters:: input (Optional[QgsRasterInterface])
Return type:: bool

virtual setOn(self, on: bool)[source]¶

Sets whether the interface is on or off

Parameters:: on (bool)

virtual sourceDataType(self, bandNo: int) → Qgis.DataType[source]¶

Returns source data type for the band specified by number, source data type may be shorter than dataType

Parameters:: bandNo (int)
Return type:: Qgis.DataType

virtual sourceInput(self) → QgsRasterInterface | None[source]¶

Gets source / raw input, the first in pipe, usually provider. It may be used to get info about original data, e.g. resolution to decide resampling etc.

Return type:: Optional[QgsRasterInterface]

virtual writeXml(self, doc: QDomDocument, parentElem: QDomElement)[source]¶

Write base class members to xml.

Parameters:

doc (QDomDocument)
parentElem (QDomElement)

virtual xBlockSize(self) → int[source]¶

Gets block size

Return type:: int

virtual xSize(self) → int[source]¶

Gets raster size

Return type:: int

virtual yBlockSize(self) → int[source]¶

Return type:: int

virtual ySize(self) → int[source]¶

Return type:: int