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
Methods
Returns the expected extent of the resulting aligned raster
Returns the expected size of the resulting aligned raster
Gets output cell size
Determine destination extent from the input rasters and calculate derived values
Gets clipping extent (region of interest).
Internal function for processing of one raster (1.
Gets the output CRS in WKT format
write contents of the object to standard error stream - for debugging
Returns the error from a previous
run()
call.- rtype
QPointF
Gets associated progress handler.
Gets list of rasters that will be aligned
Run the alignment process
Sets output cell size
Configure clipping extent (region of interest).
Sets the output CRS in WKT format
- param offset
Set destination CRS, cell size and grid offset from a raster file.
Assign a progress handler instance.
Sets list of rasters that will be aligned
Returns the index of the layer which has smallest cell size (returns -1 on error)
Determine suggested output of raster warp to a different CRS.
Attributes
-
class
Item
(input: str, output: str)¶ Bases:
sip.wrapper
QgsAlignRaster.Item(QgsAlignRaster.Item)
- Parameters
input (str) –
output (str) –
-
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 (float) – Overall progress of the alignment operation
- Return type
bool
- 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
- Parameters
layerpath (str) –
-
bandCount
(self) → int¶ Returns the number of raster bands in the file
- Return type
int
-
cellSize
(self) → QSizeF¶ Returns the cell size in map units
- Return type
QSizeF
-
crs
(self) → str¶ Returns the CRS in WKT format
- Return type
str
-
dump
(self)¶ Write contents of the object to standard error stream - for debugging
-
extent
(self) → QgsRectangle¶ Returns the extent of the raster
- Return type
-
gridOffset
(self) → QPointF¶ Returns the grid offset
- Return type
QPointF
-
identify
(self, mx: float, my: float) → float¶ Gets raster value at the given coordinates (from the first band)
- Parameters
mx (float) –
my (float) –
- Return type
float
-
isValid
(self) → bool¶ Check whether the given path is a valid raster
- Return type
bool
-
origin
(self) → QPointF¶ Returns the origin of the raster
- Return type
QPointF
-
rasterSize
(self) → QSize¶ Returns the size of the raster grid in pixels
- Return type
QSize
-
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- Return type
-
alignedRasterSize
(self) → QSize¶ Returns the expected size of the resulting aligned raster
Note
first need to run
checkInputParameters()
which returns with success- Return type
QSize
-
cellSize
(self) → QSizeF¶ Gets output cell size
- Return type
QSizeF
-
checkInputParameters
(self) → bool¶ Determine destination extent from the input rasters and calculate derived values
- Return type
bool
- Returns
True
on success, sets error on error (seeerrorMessage()
)
-
clipExtent
(self) → QgsRectangle¶ Gets clipping extent (region of interest). No extra clipping is done if the rectangle is null
- Return type
-
createAndWarp
(self, raster: QgsAlignRaster.Item) → bool¶ Internal function for processing of one raster (1. create output, 2. do the alignment)
- Parameters
raster (QgsAlignRaster.Item) –
- Return type
bool
-
destinationCrs
(self) → str¶ Gets the output CRS in WKT format
- Return type
str
-
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 ifrun()
succeeded (returnedTrue
)- Return type
str
-
gridOffset
(self) → QPointF¶ - Return type
QPointF
-
progressHandler
(self) → QgsAlignRaster.ProgressHandler¶ Gets associated progress handler. May be
None
(default)- Return type
-
rasters
(self) → List[QgsAlignRaster.Item]¶ Gets list of rasters that will be aligned
- Return type
List[QgsAlignRaster.Item]
-
run
(self) → bool¶ Run the alignment process
- Return type
bool
- Returns
True
on success, sets error on error (seeerrorMessage()
)
-
setCellSize
(self, x: float, y: float)¶ Sets output cell size
setCellSize(self, size: QSizeF) Sets output cell size
- Parameters
x (float) –
y (float) –
-
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- Parameters
xmin (float) –
ymin (float) –
xmax (float) –
ymax (float) –
-
setDestinationCrs
(self, crsWkt: str)¶ Sets the output CRS in WKT format
- Parameters
crsWkt (str) –
-
setGridOffset
(self, offset: Union[QPointF, QPoint])¶ - Parameters
offset (Union[QPointF) –
-
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.
- Return type
bool
- 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.
- Parameters
rasterInfo (QgsAlignRaster.RasterInfo) –
customCRSWkt (str = '') –
customCellSize (QSizeF = QSizeF()) –
customGridOffset (Union[QPointF) –
-
setProgressHandler
(self, progressHandler: QgsAlignRaster.ProgressHandler)¶ Assign a progress handler instance. Does not take ownership.
None
can be passed.- Parameters
progressHandler (QgsAlignRaster.ProgressHandler) –
-
setRasters
(self, list: Iterable[QgsAlignRaster.Item])¶ Sets list of rasters that will be aligned
- Parameters
list (Iterable[QgsAlignRaster.Item]) –
-
suggestedReferenceLayer
(self) → int¶ Returns the index of the layer which has smallest cell size (returns -1 on error)
- Return type
int
-
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- Parameters
info (QgsAlignRaster.RasterInfo) –
destWkt (str) –
cellSize (QSizeF = None) –
gridOffset (Union[QPointF) –
rect (
QgsRectangle
= None) –
- Return type
bool