Class: QgsAlignRaster¶

class qgis.analysis.QgsAlignRaster¶

Bases: sip.wrapper

QgsAlignRaster takes one or more raster layers and warps (resamples) them so they have the same: - coordinate reference system - cell size and raster size - offset of the raster grid

New in version 2.12: Enums

Methods

`alignedRasterExtent`	Returns the expected extent of the resulting aligned raster
`alignedRasterSize`	Returns the expected size of the resulting aligned raster
`cellSize`	Gets output cell size
`checkInputParameters`	Determine destination extent from the input rasters and calculate derived values
`clipExtent`	Gets clipping extent (region of interest).
`createAndWarp`	Internal function for processing of one raster (1.
`destinationCrs`	Gets the output CRS in WKT format
`dump`	write contents of the object to standard error stream - for debugging
`errorMessage`	Returns the error from a previous run() call.
`gridOffset`
`progressHandler`	Gets associated progress handler.
`rasters`	Gets list of rasters that will be aligned
`run`	Run the alignment process
`setCellSize`	Sets output cell size
`setClipExtent`	Configure clipping extent (region of interest).
`setDestinationCrs`	Sets the output CRS in WKT format
`setGridOffset`
`setParametersFromRaster`	Set destination CRS, cell size and grid offset from a raster file.
`setProgressHandler`	Assign a progress handler instance.
`setRasters`	Sets list of rasters that will be aligned
`suggestedReferenceLayer`	Returns the index of the layer which has smallest cell size (returns -1 on error)
`suggestedWarpOutput`	Determine suggested output of raster warp to a different CRS.

Signals

Attributes

`RA_Average`
`RA_Bilinear`
`RA_Cubic`
`RA_CubicSpline`
`RA_Lanczos`
`RA_Max`
`RA_Median`
`RA_Min`
`RA_Mode`
`RA_NearestNeighbour`
`RA_Q1`
`RA_Q3`

class Item(input: str, output: str)¶

Bases: sip.wrapper

QgsAlignRaster.Item(QgsAlignRaster.Item)

inputFilename¶

outputFilename¶

resampleMethod¶

rescaleValues¶

srcCellSizeInDestCRS¶

class ProgressHandler¶

Bases: sip.wrapper

QgsAlignRaster.ProgressHandler(QgsAlignRaster.ProgressHandler)

progress(self, complete: float) → bool¶

Method to be overridden for progress reporting.

Parameters: complete – Overall progress of the alignment operation
Returns: False if the execution should be canceled, True otherwise

RA_Average = 5¶

RA_Bilinear = 1¶

RA_Cubic = 2¶

RA_CubicSpline = 3¶

RA_Lanczos = 4¶

RA_Max = 8¶

RA_Median = 10¶

RA_Min = 9¶

RA_Mode = 6¶

RA_NearestNeighbour = 0¶

RA_Q1 = 11¶

RA_Q3 = 12¶

class RasterInfo(layerpath: str)¶

Bases: sip.wrapper

Construct raster info with a path to a raster file

bandCount(self) → int¶: Returns the number of raster bands in the file

cellSize(self) → QSizeF¶: Returns the cell size in map units

crs(self) → str¶: Returns the CRS in WKT format

dump(self)¶: Write contents of the object to standard error stream - for debugging

extent(self) → QgsRectangle¶: Returns the extent of the raster

gridOffset(self) → QPointF¶: Returns the grid offset

identify(self, mx: float, my: float) → float¶: Gets raster value at the given coordinates (from the first band)

isValid(self) → bool¶: Check whether the given path is a valid raster

origin(self) → QPointF¶: Returns the origin of the raster

rasterSize(self) → QSize¶: Returns the size of the raster grid in pixels

class ResampleAlg¶: Bases: int

alignedRasterExtent(self) → QgsRectangle¶: Returns the expected extent of the resulting aligned raster

Note

first need to run checkInputParameters() which returns with success

alignedRasterSize(self) → QSize¶: Returns the expected size of the resulting aligned raster

Note

first need to run checkInputParameters() which returns with success

cellSize(self) → QSizeF¶: Gets output cell size

checkInputParameters(self) → bool¶

Determine destination extent from the input rasters and calculate derived values

Returns: True on success, sets error on error (see errorMessage())

clipExtent(self) → QgsRectangle¶: Gets clipping extent (region of interest). No extra clipping is done if the rectangle is null

createAndWarp(self, raster: QgsAlignRaster.Item) → bool¶: Internal function for processing of one raster (1. create output, 2. do the alignment)

destinationCrs(self) → str¶: Gets the output CRS in WKT format

dump(self)¶: write contents of the object to standard error stream - for debugging

errorMessage(self) → str¶: Returns the error from a previous run() call. Error message is empty if run() succeeded (returned True)

gridOffset(self) → QPointF¶

progressHandler(self) → QgsAlignRaster.ProgressHandler¶: Gets associated progress handler. May be None (default)

rasters(self) → List[QgsAlignRaster.Item]¶: Gets list of rasters that will be aligned

run(self) → bool¶

Run the alignment process

Returns: True on success, sets error on error (see errorMessage())

setCellSize(self, x: float, y: float)¶

Sets output cell size

setCellSize(self, size: QSizeF) Sets output cell size

setClipExtent(self, xmin: float, ymin: float, xmax: float, ymax: float)¶

Configure clipping extent (region of interest). No extra clipping is done if the rectangle is null

setClipExtent(self, extent: QgsRectangle) Configure clipping extent (region of interest). No extra clipping is done if the rectangle is null

setDestinationCrs(self, crsWkt: str)¶: Sets the output CRS in WKT format

setGridOffset(self, offset: Union[QPointF, QPoint])¶

setParametersFromRaster(self, rasterInfo: QgsAlignRaster.RasterInfo, customCRSWkt: str = '', customCellSize: QSizeF = QSizeF(), customGridOffset: Union[QPointF, QPoint] = QPointF(-1, -1)) → bool¶

Set destination CRS, cell size and grid offset from a raster file. The user may provide custom values for some of the parameters - in such case only the remaining parameters are calculated.

If default CRS is used, the parameters are set according to the raster file’s geo-transform. If a custom CRS is provided, suggested reprojection is calculated first (using GDAL) in order to determine suitable defaults for cell size and grid offset.

Returns: True on success (may fail if it is not possible to reproject raster to given CRS)

setParametersFromRaster(self, filename: str, customCRSWkt: str = ‘’, customCellSize: QSizeF = QSizeF(), customGridOffset: Union[QPointF, QPoint] = QPointF(-1,-1)) -> bool Overridden variant for convenience, taking filename instead RasterInfo object. See the other variant for details.

setProgressHandler(self, progressHandler: QgsAlignRaster.ProgressHandler)¶: Assign a progress handler instance. Does not take ownership. None can be passed.

setRasters(self, list: Iterable[QgsAlignRaster.Item])¶: Sets list of rasters that will be aligned

suggestedReferenceLayer(self) → int¶: Returns the index of the layer which has smallest cell size (returns -1 on error)

suggestedWarpOutput(info: QgsAlignRaster.RasterInfo, destWkt: str, cellSize: QSizeF = None, gridOffset: Union[QPointF, QPoint] = None, rect: QgsRectangle = None) → bool¶: Determine suggested output of raster warp to a different CRS. Returns True on success