PAM raster band. More...

#include <gdal_pam.h>

Inheritance diagram for GDALPamRasterBand:

Public Member Functions
void	SetDescription (const char *) override
	Set object description. More...

CPLErr	SetNoDataValue (double) override
	Set the no data value for this band. More...

CPLErr	SetNoDataValueAsInt64 (int64_t nNoData) override
	Set the no data value for this band. More...

CPLErr	SetNoDataValueAsUInt64 (uint64_t nNoData) override
	Set the no data value for this band. More...

double	GetNoDataValue (int *pbSuccess=nullptr) override
	Fetch the no data value for this band. More...

int64_t	GetNoDataValueAsInt64 (int *pbSuccess=nullptr) override
	Fetch the no data value for this band. More...

uint64_t	GetNoDataValueAsUInt64 (int *pbSuccess=nullptr) override
	Fetch the no data value for this band. More...

CPLErr	DeleteNoDataValue () override
	Remove the no data value for this band. More...

CPLErr	SetColorTable (GDALColorTable *) override
	Set the raster color table. More...

GDALColorTable *	GetColorTable () override
	Fetch the color table associated with band. More...

CPLErr	SetColorInterpretation (GDALColorInterp) override
	Set color interpretation of a band. More...

GDALColorInterp	GetColorInterpretation () override
	How should this band be interpreted as color? More...

const char *	GetUnitType () override
	Return raster unit type. More...

CPLErr	SetUnitType (const char *) override
	Set unit type. More...

char **	GetCategoryNames () override
	Fetch the list of category names for this raster. More...

CPLErr	SetCategoryNames (char **) override
	Set the category names for this band. More...

double	GetOffset (int *pbSuccess=nullptr) override
	Fetch the raster value offset. More...

CPLErr	SetOffset (double) override
	Set scaling offset. More...

double	GetScale (int *pbSuccess=nullptr) override
	Fetch the raster value scale. More...

CPLErr	SetScale (double) override
	Set scaling ratio. More...

CPLErr	GetHistogram (double dfMin, double dfMax, int nBuckets, GUIntBig panHistogram, int bIncludeOutOfRange, int bApproxOK, GDALProgressFunc, void pProgressData) override
	Compute raster histogram. More...

CPLErr	GetDefaultHistogram (double pdfMin, double pdfMax, int pnBuckets, GUIntBig ppanHistogram, int bForce, GDALProgressFunc, void pProgressData) override
	Fetch default raster histogram. More...

CPLErr	SetDefaultHistogram (double dfMin, double dfMax, int nBuckets, GUIntBig *panHistogram) override
	Set default histogram. More...

CPLErr	SetMetadata (char *papszMetadata, const char pszDomain="") override
	Set metadata. More...

CPLErr	SetMetadataItem (const char pszName, const char pszValue, const char *pszDomain="") override
	Set single metadata item. More...

GDALRasterAttributeTable *	GetDefaultRAT () override
	Fetch default Raster Attribute Table. More...

CPLErr	SetDefaultRAT (const GDALRasterAttributeTable *) override
	Set default Raster Attribute Table. More...

int	GetXSize ()
	Fetch XSize of raster. More...

int	GetYSize ()
	Fetch YSize of raster. More...

int	GetBand ()
	Fetch the band number. More...

GDALDataset *	GetDataset ()
	Fetch the owning dataset handle. More...

GDALDataType	GetRasterDataType (void)
	Fetch the pixel data type for this band. More...

void	GetBlockSize (int pnXSize, int pnYSize)
	Fetch the "natural" block size of this band. More...

CPLErr	GetActualBlockSize (int nXBlockOff, int nYBlockOff, int pnXValid, int pnYValid)
	Fetch the actual block size for a given block offset. More...

virtual GDALSuggestedBlockAccessPattern	GetSuggestedBlockAccessPattern () const
	Return the suggested/most efficient access pattern to blocks (for read operations). More...

GDALAccess	GetAccess ()
	Find out if we have update permission for this band. More...

CPLErr	RasterIO (GDALRWFlag eRWFlag, int nXOff, int nYOff, int nXSize, int nYSize, void pData, int nBufXSize, int nBufYSize, GDALDataType eBufType, GSpacing nPixelSpace, GSpacing nLineSpace, GDALRasterIOExtraArg psExtraArg)
	Read/write a region of image data for this band. More...

CPLErr	ReadBlock (int nXBlockOff, int nYBlockOff, void *pImage)
	Read a block of image data efficiently. More...

CPLErr	WriteBlock (int nXBlockOff, int nYBlockOff, void *pImage)
	Write a block of image data efficiently. More...

GDALRasterBlock *	GetLockedBlockRef (int nXBlockOff, int nYBlockOff, int bJustInitialize=FALSE)
	Fetch a pointer to an internally cached raster block. More...

GDALRasterBlock *	TryGetLockedBlockRef (int nXBlockOff, int nYBlockYOff)
	Try fetching block ref. More...

CPLErr	FlushBlock (int nXBlockOff, int nYBlockOff, int bWriteDirtyBlock=TRUE)
	Flush a block out of the block cache. More...

unsigned char *	GetIndexColorTranslationTo (GDALRasterBand poReferenceBand, unsigned char pTranslationTable=nullptr, int *pApproximateMatching=nullptr)
	Compute translation table for color tables. More...

virtual CPLErr	FlushCache (bool bAtClosing=false)
	Flush raster data cache. More...

virtual CPLErr	DropCache ()
	Drop raster data cache : data in cache will be lost. More...

virtual double	GetMinimum (int *pbSuccess=nullptr)
	Fetch the minimum value for this band. More...

virtual double	GetMaximum (int *pbSuccess=nullptr)
	Fetch the maximum value for this band. More...

virtual CPLErr	Fill (double dfRealValue, double dfImaginaryValue=0)
	Fill this band with a constant value. More...

virtual CPLErr	GetStatistics (int bApproxOK, int bForce, double pdfMin, double pdfMax, double pdfMean, double padfStdDev)
	Fetch image statistics. More...

virtual CPLErr	ComputeStatistics (int bApproxOK, double pdfMin, double pdfMax, double pdfMean, double pdfStdDev, GDALProgressFunc, void *pProgressData)
	Compute image statistics. More...

virtual CPLErr	SetStatistics (double dfMin, double dfMax, double dfMean, double dfStdDev)
	Set statistics on band. More...

virtual CPLErr	ComputeRasterMinMax (int bApproxOK, double *adfMinMax)
	Compute the min/max values for a band. More...

virtual const char *	GetMetadataItem (const char pszName, const char pszDomain="") override
	Fetch single metadata item. More...

virtual int	HasArbitraryOverviews ()
	Check for arbitrary overviews. More...

virtual int	GetOverviewCount ()
	Return the number of overview layers available. More...

virtual GDALRasterBand *	GetOverview (int i)
	Fetch overview raster band object. More...

virtual GDALRasterBand *	GetRasterSampleOverview (GUIntBig)
	Fetch best sampling overview. More...

virtual CPLErr	BuildOverviews (const char pszResampling, int nOverviews, const int panOverviewList, GDALProgressFunc pfnProgress, void *pProgressData, CSLConstList papszOptions)
	If the operation is unsupported for the indicated dataset, then CE_Failure is returned, and CPLGetLastErrorNo() will return CPLE_NotSupported. More...

virtual CPLErr	AdviseRead (int nXOff, int nYOff, int nXSize, int nYSize, int nBufXSize, int nBufYSize, GDALDataType eBufType, char **papszOptions)
	Advise driver of upcoming read requests. More...

virtual GDALRasterBand *	GetMaskBand ()
	Return the mask band associated with the band. More...

virtual int	GetMaskFlags ()
	Return the status flags of the mask band associated with the band. More...

virtual CPLErr	CreateMaskBand (int nFlagsIn)
	Adds a mask band to the current band. More...

virtual bool	IsMaskBand () const
	Returns whether a band is a mask band. More...

virtual GDALMaskValueRange	GetMaskValueRange () const
	Returns the range of values that a mask band can take. More...

virtual CPLVirtualMem *	GetVirtualMemAuto (GDALRWFlag eRWFlag, int pnPixelSpace, GIntBig pnLineSpace, char **papszOptions)
	Create a CPLVirtualMem object from a GDAL raster band object. More...

int	GetDataCoverageStatus (int nXOff, int nYOff, int nXSize, int nYSize, int nMaskFlagStop=0, double *pdfDataPct=nullptr)
	Get the coverage status of a sub-window of the raster. More...

std::shared_ptr< GDALMDArray >	AsMDArray () const
	Return a view of this raster band as a 2D multidimensional GDALMDArray. More...

void	ReportError (CPLErr eErrClass, CPLErrorNum err_no, const char *fmt,...) CPL_PRINT_FUNC_FORMAT(4
	Emits an error related to a raster band. More...

int	GetMOFlags () const
	Returns the GMO_ flags. More...

void	SetMOFlags (int nFlagsIn)
	Assign GMO_flags. More...

virtual const char *	GetDescription () const
	Fetch object description. More...

virtual char **	GetMetadataDomainList ()
	Fetch list of metadata domains. More...

virtual char **	GetMetadata (const char *pszDomain="")
	Fetch metadata. More...

Static Public Member Functions
void static GDALRasterBandH	ToHandle (GDALRasterBand *poBand)
	Convert a GDALRasterBand* to a GDALRasterBandH. More...

static GDALMajorObjectH	ToHandle (GDALMajorObject *poMajorObject)
	Convert a GDALMajorObject* to a GDALMajorObjectH. More...

static GDALRasterBand *	FromHandle (GDALRasterBandH hBand)
	Convert a GDALRasterBandH to a GDALRasterBand*. More...

Protected Member Functions
virtual CPLErr	IReadBlock (int nBlockXOff, int nBlockYOff, void *pData)=0
	Default internal implementation ... More...

virtual CPLErr	IWriteBlock (int nBlockXOff, int nBlockYOff, void *pData)
	Write a block of data. More...

virtual CPLErr	IRasterIO (GDALRWFlag eRWFlag, int nXOff, int nYOff, int nXSize, int nYSize, void pData, int nBufXSize, int nBufYSize, GDALDataType eBufType, GSpacing nPixelSpace, GSpacing nLineSpace, GDALRasterIOExtraArg psExtraArg)
	Read/write a region of image data for this band. More...

virtual int	IGetDataCoverageStatus (int nXOff, int nYOff, int nXSize, int nYSize, int nMaskFlagStop, double *pdfDataPct)
	Get the coverage status of a sub-window of the raster. More...

char **	BuildMetadataDomainList (char **papszList, int bCheckNonEmpty,...) CPL_NULL_TERMINATED
	Helper function for custom implementations of GetMetadataDomainList() More...

Friends
class	GDALPamDataset

Detailed Description

PAM raster band.

Member Function Documentation

◆ AdviseRead()

CPLErr GDALRasterBand::AdviseRead	(	int	nXOff,
		int	nYOff,
		int	nXSize,
		int	nYSize,
		int	nBufXSize,
		int	nBufYSize,
		GDALDataType	eBufType,
		char **	papszOptions
	)

virtualinherited

Advise driver of upcoming read requests.

Some GDAL drivers operate more efficiently if they know in advance what set of upcoming read requests will be made. The AdviseRead() method allows an application to notify the driver of the region of interest, and at what resolution the region will be read.

Many drivers just ignore the AdviseRead() call, but it can dramatically accelerate access via some drivers.

Depending on call paths, drivers might receive several calls to AdviseRead() with the same parameters.

Parameters

nXOff	The pixel offset to the top left corner of the region of the band to be accessed. This would be zero to start from the left side.
nYOff	The line offset to the top left corner of the region of the band to be accessed. This would be zero to start from the top.
nXSize	The width of the region of the band to be accessed in pixels.
nYSize	The height of the region of the band to be accessed in lines.
nBufXSize	the width of the buffer image into which the desired region is to be read, or from which it is to be written.
nBufYSize	the height of the buffer image into which the desired region is to be read, or from which it is to be written.
eBufType	the type of the pixel values in the pData data buffer. The pixel values will automatically be translated to/from the GDALRasterBand data type as needed.
papszOptions	a list of name=value strings with special control options. Normally this is NULL.

Returns: CE_Failure if the request is invalid and CE_None if it works or is ignored.

◆ AsMDArray()

std::shared_ptr< GDALMDArray > GDALRasterBand::AsMDArray ( ) const

inherited

Return a view of this raster band as a 2D multidimensional GDALMDArray.

The band must be linked to a GDALDataset. If this dataset is not already marked as shared, it will be, so that the returned array holds a reference to it.

If the dataset has a geotransform attached, the X and Y dimensions of the returned array will have an associated indexing variable.

This is the same as the C function GDALRasterBandAsMDArray().

The "reverse" method is GDALMDArray::AsClassicDataset().

Returns: a new array, or nullptr.

Since: GDAL 3.1

◆ BuildMetadataDomainList()

char ** GDALMajorObject::BuildMetadataDomainList	(	char **	papszList,
		int	bCheckNonEmpty,
			...
	)

protectedinherited

Helper function for custom implementations of GetMetadataDomainList()

Parameters

papszList	initial list of domains. May be NULL. Will become invalid after function call (use return value)
bCheckNonEmpty	if TRUE, each candidate domain will be tested to be non empty
...	NULL terminated variadic list of candidate domains.

Returns: NULL or a string list. Must be freed with CSLDestroy()

Since: GDAL 1.11

◆ BuildOverviews()

CPLErr GDALRasterBand::BuildOverviews	(	const char *	pszResampling,
		int	nOverviews,
		const int *	panOverviewList,
		GDALProgressFunc	pfnProgress,
		void *	pProgressData,
		CSLConstList	papszOptions
	)

virtualinherited

If the operation is unsupported for the indicated dataset, then CE_Failure is returned, and CPLGetLastErrorNo() will return CPLE_NotSupported.

WARNING: It is not possible to build overviews for a single band in TIFF format, and thus this method does not work for TIFF format, or any formats that use the default overview building in TIFF format. Instead it is necessary to build overviews on the dataset as a whole using GDALDataset::BuildOverviews(). That makes this method pretty useless from a practical point of view.

Parameters

pszResampling	one of "NEAREST", "GAUSS", "CUBIC", "AVERAGE", "MODE", "AVERAGE_MAGPHASE" "RMS" or "NONE" controlling the downsampling method applied.
nOverviews	number of overviews to build.
panOverviewList	the list of overview decimation factors to build.
pfnProgress	a function to call to report progress, or NULL.
pProgressData	application data to pass to the progress function.
papszOptions	(GDAL >= 3.6) NULL terminated list of options as key=value pairs, or NULL

Returns: CE_None on success or CE_Failure if the operation doesn't work.

◆ ComputeRasterMinMax()

CPLErr GDALRasterBand::ComputeRasterMinMax	(	int	bApproxOK,
		double *	adfMinMax
	)

virtualinherited

Compute the min/max values for a band.

If approximate is OK, then the band's GetMinimum()/GetMaximum() will be trusted. If it doesn't work, a subsample of blocks will be read to get an approximate min/max. If the band has a nodata value it will be excluded from the minimum and maximum.

If bApprox is FALSE, then all pixels will be read and used to compute an exact range.

This method is the same as the C function GDALComputeRasterMinMax().

Parameters

bApproxOK	TRUE if an approximate (faster) answer is OK, otherwise FALSE.
adfMinMax	the array in which the minimum (adfMinMax[0]) and the maximum (adfMinMax[1]) are returned.

Returns: CE_None on success or CE_Failure on failure.

◆ ComputeStatistics()

CPLErr GDALRasterBand::ComputeStatistics	(	int	bApproxOK,
		double *	pdfMin,
		double *	pdfMax,
		double *	pdfMean,
		double *	pdfStdDev,
		GDALProgressFunc	pfnProgress,
		void *	pProgressData
	)

virtualinherited

Compute image statistics.

Returns the minimum, maximum, mean and standard deviation of all pixel values in this band. If approximate statistics are sufficient, the bApproxOK flag can be set to true in which case overviews, or a subset of image tiles may be used in computing the statistics.

Once computed, the statistics will generally be "set" back on the raster band using SetStatistics().

Cached statistics can be cleared with GDALDataset::ClearStatistics().

This method is the same as the C function GDALComputeRasterStatistics().

Parameters

bApproxOK	If TRUE statistics may be computed based on overviews or a subset of all tiles.
pdfMin	Location into which to load image minimum (may be NULL).
pdfMax	Location into which to load image maximum (may be NULL).-
pdfMean	Location into which to load image mean (may be NULL).
pdfStdDev	Location into which to load image standard deviation (may be NULL).
pfnProgress	a function to call to report progress, or NULL.
pProgressData	application data to pass to the progress function.

Returns: CE_None on success, or CE_Failure if an error occurs or processing is terminated by the user.

◆ CreateMaskBand()

CPLErr GDALRasterBand::CreateMaskBand ( int nFlagsIn )

virtualinherited

Adds a mask band to the current band.

The default implementation of the CreateMaskBand() method is implemented based on similar rules to the .ovr handling implemented using the GDALDefaultOverviews object. A TIFF file with the extension .msk will be created with the same basename as the original file, and it will have as many bands as the original image (or just one for GMF_PER_DATASET). The mask images will be deflate compressed tiled images with the same block size as the original image if possible. It will have INTERNAL_MASK_FLAGS_xx metadata items set at the dataset level, where xx matches the band number of a band of the main dataset. The value of those items will be the one of the nFlagsIn parameter.

Note that if you got a mask band with a previous call to GetMaskBand(), it might be invalidated by CreateMaskBand(). So you have to call GetMaskBand() again.

This method is the same as the C function GDALCreateMaskBand().

Since: GDAL 1.5.0

Parameters

nFlagsIn 0 or combination of GMF_PER_DATASET / GMF_ALPHA.

Returns: CE_None on success or CE_Failure on an error.

See also: https://gdal.org/development/rfc/rfc15_nodatabitmask.html; GDALDataset::CreateMaskBand()

◆ DeleteNoDataValue()

CPLErr GDALPamRasterBand::DeleteNoDataValue ( )

overridevirtual

Remove the no data value for this band.

This method is the same as the C function GDALDeleteRasterNoDataValue().

Returns: CE_None on success, or CE_Failure on failure. If unsupported by the driver, CE_Failure is returned by no error message will have been emitted.

Since: GDAL 2.1

Reimplemented from GDALRasterBand.

◆ DropCache()

CPLErr GDALRasterBand::DropCache ( )

virtualinherited

Drop raster data cache : data in cache will be lost.

This call will recover memory used to cache data blocks for this raster band, and ensure that new requests are referred to the underlying driver.

This method is the same as the C function GDALDropRasterCache().

Returns: CE_None on success.

Since: 3.9

◆ Fill()

CPLErr GDALRasterBand::Fill	(	double	dfRealValue,
		double	dfImaginaryValue = `0`
	)

virtualinherited

Fill this band with a constant value.

GDAL makes no guarantees about what values pixels in newly created files are set to, so this method can be used to clear a band to a specified "default" value. The fill value is passed in as a double but this will be converted to the underlying type before writing to the file. An optional second argument allows the imaginary component of a complex constant value to be specified.

This method is the same as the C function GDALFillRaster().

Parameters

dfRealValue	Real component of fill value
dfImaginaryValue	Imaginary component of fill value, defaults to zero

Returns: CE_Failure if the write fails, otherwise CE_None

◆ FlushBlock()

CPLErr GDALRasterBand::FlushBlock	(	int	nXBlockOff,
		int	nYBlockOff,
		int	bWriteDirtyBlock = `TRUE`
	)

inherited

Flush a block out of the block cache.

Parameters

nXBlockOff	block x offset
nYBlockOff	blocky offset
bWriteDirtyBlock	whether the block should be written to disk if dirty.

Returns: CE_None in case of success, an error code otherwise.

◆ FlushCache()

CPLErr GDALRasterBand::FlushCache ( bool bAtClosing = false )

virtualinherited

Flush raster data cache.

This call will recover memory used to cache data blocks for this raster band, and ensure that new requests are referred to the underlying driver.

This method is the same as the C function GDALFlushRasterCache().

Parameters

bAtClosing Whether this is called from a GDALDataset destructor

Returns: CE_None on success.

◆ FromHandle()

static GDALRasterBand* GDALRasterBand::FromHandle ( GDALRasterBandH hBand )

inlinestaticinherited

Convert a GDALRasterBandH to a GDALRasterBand*.

Since: GDAL 2.3

◆ GetAccess()

GDALAccess GDALRasterBand::GetAccess ( )

inherited

Find out if we have update permission for this band.

This method is the same as the C function GDALGetRasterAccess().

Returns: Either GA_Update or GA_ReadOnly.

◆ GetActualBlockSize()

CPLErr GDALRasterBand::GetActualBlockSize	(	int	nXBlockOff,
		int	nYBlockOff,
		int *	pnXValid,
		int *	pnYValid
	)

inherited

Fetch the actual block size for a given block offset.

Handles partial blocks at the edges of the raster and returns the true number of pixels

Parameters

nXBlockOff	the horizontal block offset for which to calculate the number of valid pixels, with zero indicating the left most block, 1 the next block and so forth.
nYBlockOff	the vertical block offset, with zero indicating the top most block, 1 the next block and so forth.
pnXValid	pointer to an integer in which the number of valid pixels in the x direction will be stored
pnYValid	pointer to an integer in which the number of valid pixels in the y direction will be stored

Returns: CE_None if the input parameters are valid, CE_Failure otherwise

Since: GDAL 2.2

◆ GetBand()

int GDALRasterBand::GetBand ( )

inherited

Fetch the band number.

This method returns the band that this GDALRasterBand objects represents within its dataset. This method may return a value of 0 to indicate GDALRasterBand objects without an apparently relationship to a dataset, such as GDALRasterBands serving as overviews.

This method is the same as the C function GDALGetBandNumber().

Returns: band number (1+) or 0 if the band number isn't known.

◆ GetBlockSize()

void GDALRasterBand::GetBlockSize	(	int *	pnXSize,
		int *	pnYSize
	)

inherited

Fetch the "natural" block size of this band.

GDAL contains a concept of the natural block size of rasters so that applications can organized data access efficiently for some file formats. The natural block size is the block size that is most efficient for accessing the format. For many formats this is simple a whole scanline in which case *pnXSize is set to GetXSize(), and *pnYSize is set to 1.

However, for tiled images this will typically be the tile size.

Note that the X and Y block sizes don't have to divide the image size evenly, meaning that right and bottom edge blocks may be incomplete. See ReadBlock() for an example of code dealing with these issues.

This method is the same as the C function GDALGetBlockSize().

Parameters

pnXSize	integer to put the X block size into or NULL.
pnYSize	integer to put the Y block size into or NULL.

◆ GetCategoryNames()

char ** GDALPamRasterBand::GetCategoryNames ( )

overridevirtual

Fetch the list of category names for this raster.

The return list is a "StringList" in the sense of the CPL functions. That is a NULL terminated array of strings. Raster values without associated names will have an empty string in the returned list. The first entry in the list is for raster values of zero, and so on.

The returned stringlist should not be altered or freed by the application. It may change on the next GDAL call, so please copy it if it is needed for any period of time.

This method is the same as the C function GDALGetRasterCategoryNames().

Returns: list of names, or NULL if none.

Reimplemented from GDALRasterBand.

◆ GetColorInterpretation()

GDALColorInterp GDALPamRasterBand::GetColorInterpretation ( )

overridevirtual

How should this band be interpreted as color?

GCI_Undefined is returned when the format doesn't know anything about the color interpretation.

This method is the same as the C function GDALGetRasterColorInterpretation().

Returns: color interpretation value for band.

Reimplemented from GDALRasterBand.

◆ GetColorTable()

GDALColorTable * GDALPamRasterBand::GetColorTable ( )

overridevirtual

Fetch the color table associated with band.

If there is no associated color table, the return result is NULL. The returned color table remains owned by the GDALRasterBand, and can't be depended on for long, nor should it ever be modified by the caller.

This method is the same as the C function GDALGetRasterColorTable().

Returns: internal color table, or NULL.

Reimplemented from GDALRasterBand.

◆ GetDataCoverageStatus()

int GDALRasterBand::GetDataCoverageStatus	(	int	nXOff,
		int	nYOff,
		int	nXSize,
		int	nYSize,
		int	nMaskFlagStop = `0`,
		double *	pdfDataPct = `nullptr`
	)

inherited

Get the coverage status of a sub-window of the raster.

Returns whether a sub-window of the raster contains only data, only empty blocks or a mix of both. This function can be used to determine quickly if it is worth issuing RasterIO / ReadBlock requests in datasets that may be sparse.

Empty blocks are blocks that contain only pixels whose value is the nodata value when it is set, or whose value is 0 when the nodata value is not set.

The query is done in an efficient way without reading the actual pixel values. If not possible, or not implemented at all by the driver, GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED | GDAL_DATA_COVERAGE_STATUS_DATA will be returned.

The values that can be returned by the function are the following, potentially combined with the binary or operator :

GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED : the driver does not implement GetDataCoverageStatus(). This flag should be returned together with GDAL_DATA_COVERAGE_STATUS_DATA.
GDAL_DATA_COVERAGE_STATUS_DATA: There is (potentially) data in the queried window.
GDAL_DATA_COVERAGE_STATUS_EMPTY: There is nodata in the queried window. This is typically identified by the concept of missing block in formats that supports it.

Note that GDAL_DATA_COVERAGE_STATUS_DATA might have false positives and should be interpreted more as hint of potential presence of data. For example if a GeoTIFF file is created with blocks filled with zeroes (or set to the nodata value), instead of using the missing block mechanism, GDAL_DATA_COVERAGE_STATUS_DATA will be returned. On the contrary, GDAL_DATA_COVERAGE_STATUS_EMPTY should have no false positives.

The nMaskFlagStop should be generally set to 0. It can be set to a binary-or'ed mask of the above mentioned values to enable a quick exiting of the function as soon as the computed mask matches the nMaskFlagStop. For example, you can issue a request on the whole raster with nMaskFlagStop = GDAL_DATA_COVERAGE_STATUS_EMPTY. As soon as one missing block is encountered, the function will exit, so that you can potentially refine the requested area to find which particular region(s) have missing blocks.

See also: GDALGetDataCoverageStatus()

Parameters

nXOff	The pixel offset to the top left corner of the region of the band to be queried. This would be zero to start from the left side.
nYOff	The line offset to the top left corner of the region of the band to be queried. This would be zero to start from the top.
nXSize	The width of the region of the band to be queried in pixels.
nYSize	The height of the region of the band to be queried in lines.
nMaskFlagStop	0, or a binary-or'ed mask of possible values GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED, GDAL_DATA_COVERAGE_STATUS_DATA and GDAL_DATA_COVERAGE_STATUS_EMPTY. As soon as the computation of the coverage matches the mask, the computation will be stopped. *pdfDataPct will not be valid in that case.
pdfDataPct	Optional output parameter whose pointed value will be set to the (approximate) percentage in [0,100] of pixels in the queried sub-window that have valid values. The implementation might not always be able to compute it, in which case it will be set to a negative value.

Returns: a binary-or'ed combination of possible values GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED, GDAL_DATA_COVERAGE_STATUS_DATA and GDAL_DATA_COVERAGE_STATUS_EMPTY

Note: Added in GDAL 2.2

◆ GetDataset()

GDALDataset * GDALRasterBand::GetDataset ( )

inherited

Fetch the owning dataset handle.

Note that some GDALRasterBands are not considered to be a part of a dataset, such as overviews or other "freestanding" bands.

This method is the same as the C function GDALGetBandDataset().

Returns: the pointer to the GDALDataset to which this band belongs, or NULL if this cannot be determined.

◆ GetDefaultHistogram()

CPLErr GDALPamRasterBand::GetDefaultHistogram	(	double *	pdfMin,
		double *	pdfMax,
		int *	pnBuckets,
		GUIntBig **	ppanHistogram,
		int	bForce,
		GDALProgressFunc	pfnProgress,
		void *	pProgressData
	)

overridevirtual

Fetch default raster histogram.

The default method in GDALRasterBand will compute a default histogram. This method is overridden by derived classes (such as GDALPamRasterBand, VRTDataset, HFADataset...) that may be able to fetch efficiently an already stored histogram.

This method is the same as the C functions GDALGetDefaultHistogram() and GDALGetDefaultHistogramEx().

Parameters

pdfMin	pointer to double value that will contain the lower bound of the histogram.
pdfMax	pointer to double value that will contain the upper bound of the histogram.
pnBuckets	pointer to int value that will contain the number of buckets in *ppanHistogram.
ppanHistogram	pointer to array into which the histogram totals are placed. To be freed with VSIFree
bForce	TRUE to force the computation. If FALSE and no default histogram is available, the method will return CE_Warning
pfnProgress	function to report progress to completion.
pProgressData	application data to pass to pfnProgress.

Returns: CE_None on success, CE_Failure if something goes wrong, or CE_Warning if no default histogram is available.

Reimplemented from GDALRasterBand.

◆ GetDefaultRAT()

GDALRasterAttributeTable * GDALPamRasterBand::GetDefaultRAT ( )

overridevirtual

Fetch default Raster Attribute Table.

A RAT will be returned if there is a default one associated with the band, otherwise NULL is returned. The returned RAT is owned by the band and should not be deleted by the application.

This method is the same as the C function GDALGetDefaultRAT().

Returns: NULL, or a pointer to an internal RAT owned by the band.

Reimplemented from GDALRasterBand.

◆ GetDescription()

const char * GDALMajorObject::GetDescription ( ) const

virtualinherited

Fetch object description.

The semantics of the returned description are specific to the derived type. For GDALDatasets it is the dataset name. For GDALRasterBands it is actually a description (if supported) or "".

This method is the same as the C function GDALGetDescription().

Returns: non-null pointer to internal description string.

◆ GetHistogram()

CPLErr GDALPamRasterBand::GetHistogram	(	double	dfMin,
		double	dfMax,
		int	nBuckets,
		GUIntBig *	panHistogram,
		int	bIncludeOutOfRange,
		int	bApproxOK,
		GDALProgressFunc	pfnProgress,
		void *	pProgressData
	)

overridevirtual

Compute raster histogram.

Note that the bucket size is (dfMax-dfMin) / nBuckets.

For example to compute a simple 256 entry histogram of eight bit data, the following would be suitable. The unusual bounds are to ensure that bucket boundaries don't fall right on integer values causing possible errors due to rounding after scaling.

GUIntBig anHistogram[256];
 
poBand->GetHistogram( -0.5, 255.5, 256, anHistogram, FALSE, FALSE,
                      GDALDummyProgress, nullptr );

Note that setting bApproxOK will generally result in a subsampling of the file, and will utilize overviews if available. It should generally produce a representative histogram for the data that is suitable for use in generating histogram based luts for instance. Generally bApproxOK is much faster than an exactly computed histogram.

This method is the same as the C functions GDALGetRasterHistogram() and GDALGetRasterHistogramEx().

Parameters

dfMin	the lower bound of the histogram.
dfMax	the upper bound of the histogram.
nBuckets	the number of buckets in panHistogram.
panHistogram	array into which the histogram totals are placed.
bIncludeOutOfRange	if TRUE values below the histogram range will mapped into panHistogram[0], and values above will be mapped into panHistogram[nBuckets-1] otherwise out of range values are discarded.
bApproxOK	TRUE if an approximate, or incomplete histogram OK.
pfnProgress	function to report progress to completion.
pProgressData	application data to pass to pfnProgress.

Returns: CE_None on success, or CE_Failure if something goes wrong.

Reimplemented from GDALRasterBand.

◆ GetIndexColorTranslationTo()

unsigned char * GDALRasterBand::GetIndexColorTranslationTo	(	GDALRasterBand *	poReferenceBand,
		unsigned char *	pTranslationTable = `nullptr`,
		int *	pApproximateMatching = `nullptr`
	)

inherited

Compute translation table for color tables.

When the raster band has a palette index, it may be useful to compute the "translation" of this palette to the palette of another band. The translation tries to do exact matching first, and then approximate matching if no exact matching is possible. This method returns a table such that table[i] = j where i is an index of the 'this' rasterband and j the corresponding index for the reference rasterband.

This method is thought as internal to GDAL and is used for drivers like RPFTOC.

The implementation only supports 1-byte palette rasterbands.

Parameters

poReferenceBand	the raster band
pTranslationTable	an already allocated translation table (at least 256 bytes), or NULL to let the method allocate it
pApproximateMatching	a pointer to a flag that is set if the matching is approximate. May be NULL.

Returns: a translation table if the two bands are palette index and that they do not match or NULL in other cases. The table must be freed with CPLFree if NULL was passed for pTranslationTable.

◆ GetLockedBlockRef()

GDALRasterBlock * GDALRasterBand::GetLockedBlockRef	(	int	nXBlockOff,
		int	nYBlockOff,
		int	bJustInitialize = `FALSE`
	)

inherited

Fetch a pointer to an internally cached raster block.

This method will returned the requested block (locked) if it is already in the block cache for the layer. If not, the block will be read from the driver, and placed in the layer block cached, then returned. If an error occurs reading the block from the driver, a NULL value will be returned.

If a non-NULL value is returned, then a lock for the block will have been acquired on behalf of the caller. It is absolutely imperative that the caller release this lock (with GDALRasterBlock::DropLock()) or else severe problems may result.

Note that calling GetLockedBlockRef() on a previously uncached band will enable caching.

Parameters

nXBlockOff	the horizontal block offset, with zero indicating the left most block, 1 the next block and so forth.
nYBlockOff	the vertical block offset, with zero indicating the top most block, 1 the next block and so forth.
bJustInitialize	If TRUE the block will be allocated and initialized, but not actually read from the source. This is useful when it will just be completely set and written back.

Returns: pointer to the block object, or NULL on failure.

◆ GetMaskBand()

GDALRasterBand * GDALRasterBand::GetMaskBand ( )

virtualinherited

Return the mask band associated with the band.

The GDALRasterBand class includes a default implementation of GetMaskBand() that returns one of four default implementations :

If a corresponding .msk file exists it will be used for the mask band.
If the dataset has a NODATA_VALUES metadata item, an instance of the new GDALNoDataValuesMaskBand class will be returned. GetMaskFlags() will return GMF_NODATA | GMF_PER_DATASET.
If the band has a nodata value set, an instance of the new GDALNodataMaskRasterBand class will be returned. GetMaskFlags() will return GMF_NODATA.
If there is no nodata value, but the dataset has an alpha band that seems to apply to this band (specific rules yet to be determined) and that is of type GDT_Byte then that alpha band will be returned, and the flags GMF_PER_DATASET and GMF_ALPHA will be returned in the flags.
If neither of the above apply, an instance of the new GDALAllValidRasterBand class will be returned that has 255 values for all pixels. The null flags will return GMF_ALL_VALID.

Note that the GetMaskBand() should always return a GDALRasterBand mask, even if it is only an all 255 mask with the flags indicating GMF_ALL_VALID.

For an external .msk file to be recognized by GDAL, it must be a valid GDAL dataset, with the same name as the main dataset and suffixed with .msk, with either one band (in the GMF_PER_DATASET case), or as many bands as the main dataset. It must have INTERNAL_MASK_FLAGS_xx metadata items set at the dataset level, where xx matches the band number of a band of the main dataset. The value of those items is a combination of the flags GMF_ALL_VALID, GMF_PER_DATASET, GMF_ALPHA and GMF_NODATA. If a metadata item is missing for a band, then the other rules explained above will be used to generate a on-the-fly mask band.

See also: CreateMaskBand() for the characteristics of .msk files created by GDAL.

This method is the same as the C function GDALGetMaskBand().

Returns: a valid mask band.

Since: GDAL 1.5.0

See also: https://gdal.org/development/rfc/rfc15_nodatabitmask.html

◆ GetMaskFlags()

int GDALRasterBand::GetMaskFlags ( )

virtualinherited

Return the status flags of the mask band associated with the band.

The GetMaskFlags() method returns an bitwise OR-ed set of status flags with the following available definitions that may be extended in the future:

GMF_ALL_VALID(0x01): There are no invalid pixels, all mask values will be
1. When used this will normally be the only flag set.
GMF_PER_DATASET(0x02): The mask band is shared between all bands on the dataset.
GMF_ALPHA(0x04): The mask band is actually an alpha band and may have values other than 0 and 255.
GMF_NODATA(0x08): Indicates the mask is actually being generated from nodata values. (mutually exclusive of GMF_ALPHA)

The GDALRasterBand class includes a default implementation of GetMaskBand() that returns one of four default implementations:

If a corresponding .msk file exists it will be used for the mask band.
If the dataset has a NODATA_VALUES metadata item, an instance of the new GDALNoDataValuesMaskBand class will be returned. GetMaskFlags() will return GMF_NODATA | GMF_PER_DATASET.
If the band has a nodata value set, an instance of the new GDALNodataMaskRasterBand class will be returned. GetMaskFlags() will return GMF_NODATA.
If there is no nodata value, but the dataset has an alpha band that seems to apply to this band (specific rules yet to be determined) and that is of type GDT_Byte then that alpha band will be returned, and the flags GMF_PER_DATASET and GMF_ALPHA will be returned in the flags.
If neither of the above apply, an instance of the new GDALAllValidRasterBand class will be returned that has 255 values for all pixels. The null flags will return GMF_ALL_VALID.

For an external .msk file to be recognized by GDAL, it must be a valid GDAL dataset, with the same name as the main dataset and suffixed with .msk, with either one band (in the GMF_PER_DATASET case), or as many bands as the main dataset. It must have INTERNAL_MASK_FLAGS_xx metadata items set at the dataset level, where xx matches the band number of a band of the main dataset. The value of those items is a combination of the flags GMF_ALL_VALID, GMF_PER_DATASET, GMF_ALPHA and GMF_NODATA. If a metadata item is missing for a band, then the other rules explained above will be used to generate a on-the-fly mask band.

See also: CreateMaskBand() for the characteristics of .msk files created by GDAL.

This method is the same as the C function GDALGetMaskFlags().

Since: GDAL 1.5.0

Returns: a valid mask band.

See also: https://gdal.org/development/rfc/rfc15_nodatabitmask.html

◆ GetMaskValueRange()

GDALMaskValueRange GDALRasterBand::GetMaskValueRange ( ) const

virtualinherited

Returns the range of values that a mask band can take.

Returns: the range of values that a mask band can take.

Since: GDAL 3.5.0

◆ GetMaximum()

double GDALRasterBand::GetMaximum ( int * pbSuccess = nullptr )

virtualinherited

Fetch the maximum value for this band.

For file formats that don't know this intrinsically, the maximum supported value for the data type will generally be returned.

This method is the same as the C function GDALGetRasterMaximum().

Parameters

pbSuccess pointer to a boolean to use to indicate if the returned value is a tight maximum or not. May be NULL (default).

Returns: the maximum raster value (excluding no data pixels)

◆ GetMetadata()

char ** GDALMajorObject::GetMetadata ( const char * pszDomain = "" )

virtualinherited

Fetch metadata.

The returned string list is owned by the object, and may change at any time. It is formatted as a "Name=value" list with the last pointer value being NULL. Use the CPL StringList functions such as CSLFetchNameValue() to manipulate it.

Note that relatively few formats return any metadata at this time.

This method does the same thing as the C function GDALGetMetadata().

Parameters

pszDomain the domain of interest. Use "" or NULL for the default domain.

Returns: NULL or a string list.

Reimplemented in GDALDataset, GDALPamDataset, and GDALPluginDriverProxy.

◆ GetMetadataDomainList()

char ** GDALMajorObject::GetMetadataDomainList ( )

virtualinherited

Fetch list of metadata domains.

The returned string list is the list of (non-empty) metadata domains.

This method does the same thing as the C function GDALGetMetadataDomainList().

Returns: NULL or a string list. Must be freed with CSLDestroy()

Since: GDAL 1.11

Reimplemented in GDALDataset.

◆ GetMetadataItem()

const char * GDALRasterBand::GetMetadataItem	(	const char *	pszName,
		const char *	pszDomain = `""`
	)

overridevirtualinherited

Fetch single metadata item.

The C function GDALGetMetadataItem() does the same thing as this method.

Parameters

pszName	the key for the metadata item to fetch.
pszDomain	the domain to fetch for, use NULL for the default domain.

Returns: NULL on failure to find the key, or a pointer to an internal copy of the value string on success.

Reimplemented from GDALMajorObject.

◆ GetMinimum()

double GDALRasterBand::GetMinimum ( int * pbSuccess = nullptr )

virtualinherited

Fetch the minimum value for this band.

For file formats that don't know this intrinsically, the minimum supported value for the data type will generally be returned.

This method is the same as the C function GDALGetRasterMinimum().

Parameters

pbSuccess pointer to a boolean to use to indicate if the returned value is a tight minimum or not. May be NULL (default).

Returns: the minimum raster value (excluding no data pixels)

◆ GetMOFlags()

int GDALMajorObject::GetMOFlags ( ) const

inherited

Returns the GMO_ flags.

Returns: flags

◆ GetNoDataValue()

double GDALPamRasterBand::GetNoDataValue ( int * pbSuccess = nullptr )

overridevirtual

Fetch the no data value for this band.

If there is no out of data value, an out of range value will generally be returned. The no data value for a band is generally a special marker value used to mark pixels that are not valid data. Such pixels should generally not be displayed, nor contribute to analysis operations.

The no data value returned is 'raw', meaning that it has no offset and scale applied.

For rasters of type GDT_Int64 or GDT_UInt64, using this method might be lossy if the nodata value cannot exactly been represented by a double. Use GetNoDataValueAsInt64() or GetNoDataValueAsUInt64() instead.

This method is the same as the C function GDALGetRasterNoDataValue().

Parameters

pbSuccess pointer to a boolean to use to indicate if a value is actually associated with this layer. May be NULL (default).

Returns: the nodata value for this band.

Reimplemented from GDALRasterBand.

◆ GetNoDataValueAsInt64()

int64_t GDALPamRasterBand::GetNoDataValueAsInt64 ( int * pbSuccess = nullptr )

overridevirtual

Fetch the no data value for this band.

This method should ONLY be called on rasters whose data type is GDT_Int64.

If there is no out of data value, an out of range value will generally be returned. The no data value for a band is generally a special marker value used to mark pixels that are not valid data. Such pixels should generally not be displayed, nor contribute to analysis operations.

The no data value returned is 'raw', meaning that it has no offset and scale applied.

This method is the same as the C function GDALGetRasterNoDataValueAsInt64().

Parameters

pbSuccess pointer to a boolean to use to indicate if a value is actually associated with this layer. May be NULL (default).

Returns: the nodata value for this band.

Since: GDAL 3.5

Reimplemented from GDALRasterBand.

◆ GetNoDataValueAsUInt64()

uint64_t GDALPamRasterBand::GetNoDataValueAsUInt64 ( int * pbSuccess = nullptr )

overridevirtual

Fetch the no data value for this band.

This method should ONLY be called on rasters whose data type is GDT_UInt64.

If there is no out of data value, an out of range value will generally be returned. The no data value for a band is generally a special marker value used to mark pixels that are not valid data. Such pixels should generally not be displayed, nor contribute to analysis operations.

The no data value returned is 'raw', meaning that it has no offset and scale applied.

This method is the same as the C function GDALGetRasterNoDataValueAsUInt64().

Parameters

pbSuccess pointer to a boolean to use to indicate if a value is actually associated with this layer. May be NULL (default).

Returns: the nodata value for this band.

Since: GDAL 3.5

Reimplemented from GDALRasterBand.

◆ GetOffset()

double GDALPamRasterBand::GetOffset ( int * pbSuccess = nullptr )

overridevirtual

Fetch the raster value offset.

This value (in combination with the GetScale() value) can be used to transform raw pixel values into the units returned by GetUnitType(). For example this might be used to store elevations in GUInt16 bands with a precision of 0.1, and starting from -100.

Units value = (raw value * scale) + offset

Note that applying scale and offset is of the responsibility of the user, and is not done by methods such as RasterIO() or ReadBlock().

For file formats that don't know this intrinsically a value of zero is returned.

This method is the same as the C function GDALGetRasterOffset().

Parameters

pbSuccess pointer to a boolean to use to indicate if the returned value is meaningful or not. May be NULL (default).

Returns: the raster offset.

Reimplemented from GDALRasterBand.

◆ GetOverview()

GDALRasterBand * GDALRasterBand::GetOverview ( int i )

virtualinherited

Fetch overview raster band object.

This method is the same as the C function GDALGetOverview().

Parameters

i	overview index between 0 and GetOverviewCount()-1.

Returns: overview GDALRasterBand.

◆ GetOverviewCount()

int GDALRasterBand::GetOverviewCount ( )

virtualinherited

Return the number of overview layers available.

This method is the same as the C function GDALGetOverviewCount().

Returns: overview count, zero if none.

◆ GetRasterDataType()

GDALDataType GDALRasterBand::GetRasterDataType ( void )

inherited

Fetch the pixel data type for this band.

This method is the same as the C function GDALGetRasterDataType().

Returns: the data type of pixels for this band.

◆ GetRasterSampleOverview()

GDALRasterBand * GDALRasterBand::GetRasterSampleOverview ( GUIntBig nDesiredSamples )

virtualinherited

Fetch best sampling overview.

Returns the most reduced overview of the given band that still satisfies the desired number of samples. This function can be used with zero as the number of desired samples to fetch the most reduced overview. The same band as was passed in will be returned if it has not overviews, or if none of the overviews have enough samples.

This method is the same as the C functions GDALGetRasterSampleOverview() and GDALGetRasterSampleOverviewEx().

Parameters

nDesiredSamples the returned band will have at least this many pixels.

Returns: optimal overview or the band itself.

◆ GetScale()

double GDALPamRasterBand::GetScale ( int * pbSuccess = nullptr )

overridevirtual

Fetch the raster value scale.

This value (in combination with the GetOffset() value) can be used to transform raw pixel values into the units returned by GetUnitType(). For example this might be used to store elevations in GUInt16 bands with a precision of 0.1, and starting from -100.

Units value = (raw value * scale) + offset

Note that applying scale and offset is of the responsibility of the user, and is not done by methods such as RasterIO() or ReadBlock().

For file formats that don't know this intrinsically a value of one is returned.

This method is the same as the C function GDALGetRasterScale().

Parameters

pbSuccess pointer to a boolean to use to indicate if the returned value is meaningful or not. May be NULL (default).

Returns: the raster scale.

Reimplemented from GDALRasterBand.

◆ GetStatistics()

CPLErr GDALRasterBand::GetStatistics	(	int	bApproxOK,
		int	bForce,
		double *	pdfMin,
		double *	pdfMax,
		double *	pdfMean,
		double *	pdfStdDev
	)

virtualinherited

Fetch image statistics.

Returns the minimum, maximum, mean and standard deviation of all pixel values in this band. If approximate statistics are sufficient, the bApproxOK flag can be set to true in which case overviews, or a subset of image tiles may be used in computing the statistics.

If bForce is FALSE results will only be returned if it can be done quickly (i.e. without scanning the image, typically by using pre-existing STATISTICS_xxx metadata items). If bForce is FALSE and results cannot be returned efficiently, the method will return CE_Warning but no warning will be issued. This is a non-standard use of the CE_Warning return value to indicate "nothing done".

If bForce is TRUE, and results are quickly available without scanning the image, they will be used. If bForce is TRUE and results are not quickly available, GetStatistics() forwards the computation to ComputeStatistics(), which will scan the image.

To always force recomputation of statistics, use ComputeStatistics() instead of this method.

Note that file formats using PAM (Persistent Auxiliary Metadata) services will generally cache statistics in the .pam file allowing fast fetch after the first request.

This method is the same as the C function GDALGetRasterStatistics().

Parameters

bApproxOK	If TRUE statistics may be computed based on overviews or a subset of all tiles.
bForce	If FALSE statistics will only be returned if it can be done without rescanning the image. If TRUE, statistics computation will be forced if pre-existing values are not quickly available.
pdfMin	Location into which to load image minimum (may be NULL).
pdfMax	Location into which to load image maximum (may be NULL).-
pdfMean	Location into which to load image mean (may be NULL).
pdfStdDev	Location into which to load image standard deviation (may be NULL).

Returns: CE_None on success, CE_Warning if no values returned, CE_Failure if an error occurs.

◆ GetSuggestedBlockAccessPattern()

GDALSuggestedBlockAccessPattern GDALRasterBand::GetSuggestedBlockAccessPattern ( ) const

virtualinherited

Return the suggested/most efficient access pattern to blocks (for read operations).

While all GDAL drivers have to expose a block size, not all can guarantee efficient random access (GSBAP_RANDOM) to any block. Some drivers for example decompress sequentially a compressed stream from top raster to bottom (GSBAP_TOP_TO_BOTTOM), in which case best performance will be achieved while reading blocks in that order. (accessing blocks in random access in such rasters typically causes the decoding to be re-initialized from the start if accessing blocks in a non-sequential order)

The base implementation returns GSBAP_UNKNOWN, which can also be explicitly returned by drivers that expose a somewhat artificial block size, because they can extract any part of a raster, but in a rather inefficient way.

The GSBAP_LARGEST_CHUNK_POSSIBLE value can be combined as a logical bitmask with other enumeration values (GSBAP_UNKNOWN, GSBAP_RANDOM, GSBAP_TOP_TO_BOTTOM, GSBAP_BOTTOM_TO_TOP). When a driver sets this flag, the most efficient strategy is to read as many pixels as possible in the less RasterIO() operations.

The return of this method is for example used to determine the swath size used by GDALDatasetCopyWholeRaster() and GDALRasterBandCopyWholeRaster().

Since: GDAL 3.6

◆ GetUnitType()

const char * GDALPamRasterBand::GetUnitType ( )

overridevirtual

Return raster unit type.

Return a name for the units of this raster's values. For instance, it might be "m" for an elevation model in meters, or "ft" for feet. If no units are available, a value of "" will be returned. The returned string should not be modified, nor freed by the calling application.

This method is the same as the C function GDALGetRasterUnitType().

Returns: unit name string.

Reimplemented from GDALRasterBand.

◆ GetVirtualMemAuto()

CPLVirtualMem * GDALRasterBand::GetVirtualMemAuto	(	GDALRWFlag	eRWFlag,
		int *	pnPixelSpace,
		GIntBig *	pnLineSpace,
		char **	papszOptions
	)

virtualinherited

Create a CPLVirtualMem object from a GDAL raster band object.

Only supported on Linux and Unix systems with mmap() for now.

This method allows creating a virtual memory object for a GDALRasterBand, that exposes the whole image data as a virtual array.

The default implementation relies on GDALRasterBandGetVirtualMem(), but specialized implementation, such as for raw files, may also directly use mechanisms of the operating system to create a view of the underlying file into virtual memory ( CPLVirtualMemFileMapNew() )

At the time of writing, the GeoTIFF driver and "raw" drivers (EHdr, ...) offer a specialized implementation with direct file mapping, provided that some requirements are met :

for all drivers, the dataset must be backed by a "real" file in the file system, and the byte ordering of multi-byte datatypes (Int16, etc.) must match the native ordering of the CPU.
in addition, for the GeoTIFF driver, the GeoTIFF file must be uncompressed, scanline oriented (i.e. not tiled). Strips must be organized in the file in sequential order, and be equally spaced (which is generally the case). Only power-of-two bit depths are supported (8 for GDT_Bye, 16 for GDT_Int16/GDT_UInt16, 32 for GDT_Float32 and 64 for GDT_Float64)

The pointer returned remains valid until CPLVirtualMemFree() is called. CPLVirtualMemFree() must be called before the raster band object is destroyed.

If p is such a pointer and base_type the type matching GDALGetRasterDataType(), the element of image coordinates (x, y) can be accessed with *(base_type*) ((GByte*)p + x * *pnPixelSpace + y * *pnLineSpace)

This method is the same as the C GDALGetVirtualMemAuto() function.

Parameters

eRWFlag	Either GF_Read to read the band, or GF_Write to read/write the band.
pnPixelSpace	Output parameter giving the byte offset from the start of one pixel value in the buffer to the start of the next pixel value within a scanline.
pnLineSpace	Output parameter giving the byte offset from the start of one scanline in the buffer to the start of the next.
papszOptions	NULL terminated list of options. If a specialized implementation exists, defining USE_DEFAULT_IMPLEMENTATION=YES will cause the default implementation to be used. On the contrary, starting with GDAL 2.2, defining USE_DEFAULT_IMPLEMENTATION=NO will prevent the default implementation from being used (thus only allowing efficient implementations to be used). When requiring or falling back to the default implementation, the following options are available : CACHE_SIZE (in bytes, defaults to 40 MB), PAGE_SIZE_HINT (in bytes), SINGLE_THREAD ("FALSE" / "TRUE", defaults to FALSE)

Returns: a virtual memory object that must be unreferenced by CPLVirtualMemFree(), or NULL in case of failure.

Since: GDAL 1.11

◆ GetXSize()

int GDALRasterBand::GetXSize ( )

inherited

Fetch XSize of raster.

This method is the same as the C function GDALGetRasterBandXSize().

Returns: the width in pixels of this band.

◆ GetYSize()

int GDALRasterBand::GetYSize ( )

inherited

Fetch YSize of raster.

This method is the same as the C function GDALGetRasterBandYSize().

Returns: the height in pixels of this band.

◆ HasArbitraryOverviews()

int GDALRasterBand::HasArbitraryOverviews ( )

virtualinherited

Check for arbitrary overviews.

This returns TRUE if the underlying datastore can compute arbitrary overviews efficiently, such as is the case with OGDI over a network. Datastores with arbitrary overviews don't generally have any fixed overviews, but the RasterIO() method can be used in downsampling mode to get overview data efficiently.

This method is the same as the C function GDALHasArbitraryOverviews(),

Returns: TRUE if arbitrary overviews available (efficiently), otherwise FALSE.

◆ IGetDataCoverageStatus()

int GDALRasterBand::IGetDataCoverageStatus	(	int	nXOff,
		int	nYOff,
		int	nXSize,
		int	nYSize,
		int	nMaskFlagStop,
		double *	pdfDataPct
	)

protectedvirtualinherited

Get the coverage status of a sub-window of the raster.

Returns whether a sub-window of the raster contains only data, only empty blocks or a mix of both. This function can be used to determine quickly if it is worth issuing RasterIO / ReadBlock requests in datasets that may be sparse.

Empty blocks are blocks that contain only pixels whose value is the nodata value when it is set, or whose value is 0 when the nodata value is not set.

The query is done in an efficient way without reading the actual pixel values. If not possible, or not implemented at all by the driver, GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED | GDAL_DATA_COVERAGE_STATUS_DATA will be returned.

The values that can be returned by the function are the following, potentially combined with the binary or operator :

GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED : the driver does not implement GetDataCoverageStatus(). This flag should be returned together with GDAL_DATA_COVERAGE_STATUS_DATA.
GDAL_DATA_COVERAGE_STATUS_DATA: There is (potentially) data in the queried window.
GDAL_DATA_COVERAGE_STATUS_EMPTY: There is nodata in the queried window. This is typically identified by the concept of missing block in formats that supports it.

Note that GDAL_DATA_COVERAGE_STATUS_DATA might have false positives and should be interpreted more as hint of potential presence of data. For example if a GeoTIFF file is created with blocks filled with zeroes (or set to the nodata value), instead of using the missing block mechanism, GDAL_DATA_COVERAGE_STATUS_DATA will be returned. On the contrary, GDAL_DATA_COVERAGE_STATUS_EMPTY should have no false positives.

The nMaskFlagStop should be generally set to 0. It can be set to a binary-or'ed mask of the above mentioned values to enable a quick exiting of the function as soon as the computed mask matches the nMaskFlagStop. For example, you can issue a request on the whole raster with nMaskFlagStop = GDAL_DATA_COVERAGE_STATUS_EMPTY. As soon as one missing block is encountered, the function will exit, so that you can potentially refine the requested area to find which particular region(s) have missing blocks.

See also: GDALGetDataCoverageStatus()

Parameters

nXOff	The pixel offset to the top left corner of the region of the band to be queried. This would be zero to start from the left side.
nYOff	The line offset to the top left corner of the region of the band to be queried. This would be zero to start from the top.
nXSize	The width of the region of the band to be queried in pixels.
nYSize	The height of the region of the band to be queried in lines.
nMaskFlagStop	0, or a binary-or'ed mask of possible values GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED, GDAL_DATA_COVERAGE_STATUS_DATA and GDAL_DATA_COVERAGE_STATUS_EMPTY. As soon as the computation of the coverage matches the mask, the computation will be stopped. *pdfDataPct will not be valid in that case.
pdfDataPct	Optional output parameter whose pointed value will be set to the (approximate) percentage in [0,100] of pixels in the queried sub-window that have valid values. The implementation might not always be able to compute it, in which case it will be set to a negative value.

Returns: a binary-or'ed combination of possible values GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED, GDAL_DATA_COVERAGE_STATUS_DATA and GDAL_DATA_COVERAGE_STATUS_EMPTY

Note: Added in GDAL 2.2

◆ IRasterIO()

CPLErr GDALRasterBand::IRasterIO	(	GDALRWFlag	eRWFlag,
		int	nXOff,
		int	nYOff,
		int	nXSize,
		int	nYSize,
		void *	pData,
		int	nBufXSize,
		int	nBufYSize,
		GDALDataType	eBufType,
		GSpacing	nPixelSpace,
		GSpacing	nLineSpace,
		GDALRasterIOExtraArg *	psExtraArg
	)

protectedvirtualinherited

Read/write a region of image data for this band.

This method allows reading a region of a GDALRasterBand into a buffer, or writing data from a buffer into a region of a GDALRasterBand. It automatically takes care of data type translation if the data type (eBufType) of the buffer is different than that of the GDALRasterBand. The method also takes care of image decimation / replication if the buffer size (nBufXSize x nBufYSize) is different than the size of the region being accessed (nXSize x nYSize).

The nPixelSpace and nLineSpace parameters allow reading into or writing from unusually organized buffers. This is primarily used for buffers containing more than one bands raster data in interleaved format.

Some formats may efficiently implement decimation into a buffer by reading from lower resolution overview images. The logic of the default implementation in the base class GDALRasterBand is the following one. It computes a target_downscaling_factor from the window of interest and buffer size which is min(nXSize/nBufXSize, nYSize/nBufYSize). It then walks through overviews and will select the first one whose downscaling factor is greater than target_downscaling_factor / 1.2.

Let's assume we have overviews at downscaling factors 2, 4 and 8. The relationship between target_downscaling_factor and the select overview level is the following one:

target_downscaling_factor	selected_overview
]0, 2 / 1.2]	full resolution band
]2 / 1.2, 4 / 1.2]	2x downsampled band
]4 / 1.2, 8 / 1.2]	4x downsampled band
]8 / 1.2, infinity[	8x downsampled band

Note that starting with GDAL 3.9, this 1.2 oversampling factor can be modified by setting the GDAL_OVERVIEW_OVERSAMPLING_THRESHOLD configuration option. Also note that starting with GDAL 3.9, when the resampling algorithm specified in psExtraArg->eResampleAlg is different from GRIORA_NearestNeighbour, this oversampling threshold defaults to 1. Consequently if there are overviews of downscaling factor 2, 4 and 8, and the desired downscaling factor is 7.99, the overview of factor 4 will be selected for a non nearest resampling.

For highest performance full resolution data access, read and write on "block boundaries" as returned by GetBlockSize(), or use the ReadBlock() and WriteBlock() methods.

This method is the same as the C GDALRasterIO() or GDALRasterIOEx() functions.

Parameters

eRWFlag	Either GF_Read to read a region of data, or GF_Write to write a region of data.
nXOff	The pixel offset to the top left corner of the region of the band to be accessed. This would be zero to start from the left side.
nYOff	The line offset to the top left corner of the region of the band to be accessed. This would be zero to start from the top.
nXSize	The width of the region of the band to be accessed in pixels.
nYSize	The height of the region of the band to be accessed in lines.
pData	The buffer into which the data should be read, or from which it should be written. This buffer must contain at least nBufXSize * nBufYSize words of type eBufType. It is organized in left to right, top to bottom pixel order. Spacing is controlled by the nPixelSpace, and nLineSpace parameters. Note that even with eRWFlag==GF_Write, the content of the buffer might be temporarily modified during the execution of this method (and eventually restored back to its original content), so it is not safe to use a buffer stored in a read-only section of the calling program.
nBufXSize	the width of the buffer image into which the desired region is to be read, or from which it is to be written.
nBufYSize	the height of the buffer image into which the desired region is to be read, or from which it is to be written.
eBufType	the type of the pixel values in the pData data buffer. The pixel values will automatically be translated to/from the GDALRasterBand data type as needed. Most driver implementations will use GDALCopyWords64() to perform data type translation.
nPixelSpace	The byte offset from the start of one pixel value in pData to the start of the next pixel value within a scanline. If defaulted (0) the size of the datatype eBufType is used.
nLineSpace	The byte offset from the start of one scanline in pData to the start of the next. If defaulted (0) the size of the datatype eBufType * nBufXSize is used.
psExtraArg	(new in GDAL 2.0) pointer to a GDALRasterIOExtraArg structure with additional arguments to specify resampling and progress callback, or NULL for default behavior. The GDAL_RASTERIO_RESAMPLING configuration option can also be defined to override the default resampling to one of BILINEAR, CUBIC, CUBICSPLINE, LANCZOS, AVERAGE or MODE.

Returns: CE_Failure if the access fails, otherwise CE_None.

◆ IReadBlock()

GDALRasterBand::IReadBlock	(	int	nBlockXOff,
		int	nBlockYOff,
		void *	pData
	)

protectedpure virtualinherited

Default internal implementation ...

to be overridden by subclasses that support reading.

Parameters

nBlockXOff	Block X Offset
nBlockYOff	Block Y Offset
pData	Pixel buffer into which to place read data.

Returns: CE_None on success or CE_Failure on an error.

◆ IsMaskBand()

bool GDALRasterBand::IsMaskBand ( ) const

virtualinherited

Returns whether a band is a mask band.

Mask band must be understood in the broad term: it can be a per-dataset mask band, an alpha band, or an implicit mask band. Typically the return of GetMaskBand()->IsMaskBand() should be true.

This method is the same as the C function GDALIsMaskBand().

Returns: true if the band is a mask band.

See also: GDALDataset::CreateMaskBand()

Since: GDAL 3.5.0

◆ IWriteBlock()

CPLErr GDALRasterBand::IWriteBlock	(	int	nBlockXOff,
		int	nBlockYOff,
		void *	pData
	)

protectedvirtualinherited

Write a block of data.

Default internal implementation ... to be overridden by subclasses that support writing.

Parameters

nBlockXOff	Block X Offset
nBlockYOff	Block Y Offset
pData	Pixel buffer to write

Returns: CE_None on success or CE_Failure on an error.

◆ RasterIO()

CPLErr GDALRasterBand::RasterIO	(	GDALRWFlag	eRWFlag,
		int	nXOff,
		int	nYOff,
		int	nXSize,
		int	nYSize,
		void *	pData,
		int	nBufXSize,
		int	nBufYSize,
		GDALDataType	eBufType,
		GSpacing	nPixelSpace,
		GSpacing	nLineSpace,
		GDALRasterIOExtraArg *	psExtraArg
	)

inherited

Read/write a region of image data for this band.

This method allows reading a region of a GDALRasterBand into a buffer, or writing data from a buffer into a region of a GDALRasterBand. It automatically takes care of data type translation if the data type (eBufType) of the buffer is different than that of the GDALRasterBand. The method also takes care of image decimation / replication if the buffer size (nBufXSize x nBufYSize) is different than the size of the region being accessed (nXSize x nYSize).

The nPixelSpace and nLineSpace parameters allow reading into or writing from unusually organized buffers. This is primarily used for buffers containing more than one bands raster data in interleaved format.

Some formats may efficiently implement decimation into a buffer by reading from lower resolution overview images. The logic of the default implementation in the base class GDALRasterBand is the following one. It computes a target_downscaling_factor from the window of interest and buffer size which is min(nXSize/nBufXSize, nYSize/nBufYSize). It then walks through overviews and will select the first one whose downscaling factor is greater than target_downscaling_factor / 1.2.

Let's assume we have overviews at downscaling factors 2, 4 and 8. The relationship between target_downscaling_factor and the select overview level is the following one:

target_downscaling_factor	selected_overview
]0, 2 / 1.2]	full resolution band
]2 / 1.2, 4 / 1.2]	2x downsampled band
]4 / 1.2, 8 / 1.2]	4x downsampled band
]8 / 1.2, infinity[	8x downsampled band

For highest performance full resolution data access, read and write on "block boundaries" as returned by GetBlockSize(), or use the ReadBlock() and WriteBlock() methods.

This method is the same as the C GDALRasterIO() or GDALRasterIOEx() functions.

Parameters

	eRWFlag	Either GF_Read to read a region of data, or GF_Write to write a region of data.
	nXOff	The pixel offset to the top left corner of the region of the band to be accessed. This would be zero to start from the left side.
	nYOff	The line offset to the top left corner of the region of the band to be accessed. This would be zero to start from the top.
	nXSize	The width of the region of the band to be accessed in pixels.
	nYSize	The height of the region of the band to be accessed in lines.
[in,out]	pData	The buffer into which the data should be read, or from which it should be written. This buffer must contain at least nBufXSize * nBufYSize words of type eBufType. It is organized in left to right, top to bottom pixel order. Spacing is controlled by the nPixelSpace, and nLineSpace parameters.
	nBufXSize	the width of the buffer image into which the desired region is to be read, or from which it is to be written.
	nBufYSize	the height of the buffer image into which the desired region is to be read, or from which it is to be written.
	eBufType	the type of the pixel values in the pData data buffer. The pixel values will automatically be translated to/from the GDALRasterBand data type as needed.
	nPixelSpace	The byte offset from the start of one pixel value in pData to the start of the next pixel value within a scanline. If defaulted (0) the size of the datatype eBufType is used.
	nLineSpace	The byte offset from the start of one scanline in pData to the start of the next. If defaulted (0) the size of the datatype eBufType * nBufXSize is used.
[in]	psExtraArg	(new in GDAL 2.0) pointer to a GDALRasterIOExtraArg structure with additional arguments to specify resampling and progress callback, or NULL for default behavior. The GDAL_RASTERIO_RESAMPLING configuration option can also be defined to override the default resampling to one of BILINEAR, CUBIC, CUBICSPLINE, LANCZOS, AVERAGE or MODE.

Returns: CE_Failure if the access fails, otherwise CE_None.

◆ ReadBlock()

CPLErr GDALRasterBand::ReadBlock	(	int	nXBlockOff,
		int	nYBlockOff,
		void *	pImage
	)

inherited

Read a block of image data efficiently.

This method accesses a "natural" block from the raster band without resampling, or data type conversion. For a more generalized, but potentially less efficient access use RasterIO().

This method is the same as the C GDALReadBlock() function.

See the GetLockedBlockRef() method for a way of accessing internally cached block oriented data without an extra copy into an application buffer.

The following code would efficiently compute a histogram of eight bit raster data. Note that the final block may be partial ... data beyond the edge of the underlying raster band in these edge blocks is of an undetermined value.

CPLErr GetHistogram( GDALRasterBand *poBand, GUIntBig *panHistogram )
 
{
    memset( panHistogram, 0, sizeof(GUIntBig) * 256 );
 
    CPLAssert( poBand->GetRasterDataType() == GDT_Byte );
 
    int nXBlockSize, nYBlockSize;
 
    poBand->GetBlockSize( &nXBlockSize, &nYBlockSize );
    int nXBlocks = (poBand->GetXSize() + nXBlockSize - 1) / nXBlockSize;
    int nYBlocks = (poBand->GetYSize() + nYBlockSize - 1) / nYBlockSize;
 
    GByte *pabyData = (GByte *) CPLMalloc(nXBlockSize * nYBlockSize);
 
    for( int iYBlock = 0; iYBlock < nYBlocks; iYBlock++ )
    {
        for( int iXBlock = 0; iXBlock < nXBlocks; iXBlock++ )
        {
            int        nXValid, nYValid;
 
            poBand->ReadBlock( iXBlock, iYBlock, pabyData );
 
            // Compute the portion of the block that is valid
            // for partial edge blocks.
            poBand->GetActualBlockSize(iXBlock, iYBlock, &nXValid, &nYValid)
 
            // Collect the histogram counts.
            for( int iY = 0; iY < nYValid; iY++ )
            {
                for( int iX = 0; iX < nXValid; iX++ )
                {
                    panHistogram[pabyData[iX + iY * nXBlockSize]] += 1;
                }
            }
        }
    }
}

Parameters

nXBlockOff	the horizontal block offset, with zero indicating the left most block, 1 the next block and so forth.
nYBlockOff	the vertical block offset, with zero indicating the top most block, 1 the next block and so forth.
pImage	the buffer into which the data will be read. The buffer must be large enough to hold GetBlockXSize()*GetBlockYSize() words of type GetRasterDataType().

Returns: CE_None on success or CE_Failure on an error.

◆ ReportError()

void GDALRasterBand::ReportError	(	CPLErr	eErrClass,
		CPLErrorNum	err_no,
		const char *	fmt,
			...
	)

inherited

Emits an error related to a raster band.

This function is a wrapper for regular CPLError(). The only difference with CPLError() is that it prepends the error message with the dataset name and the band number.

Parameters

eErrClass	one of CE_Warning, CE_Failure or CE_Fatal.
err_no	the error number (CPLE_*) from cpl_error.h.
fmt	a printf() style format string. Any additional arguments will be treated as arguments to fill in this format in a manner similar to printf().

Since: GDAL 1.9.0

◆ SetCategoryNames()

CPLErr GDALPamRasterBand::SetCategoryNames ( char ** papszNames )

overridevirtual

Set the category names for this band.

See the GetCategoryNames() method for more on the interpretation of category names.

This method is the same as the C function GDALSetRasterCategoryNames().

Parameters

papszNames the NULL terminated StringList of category names. May be NULL to just clear the existing list.

Returns: CE_None on success of CE_Failure on failure. If unsupported by the driver CE_Failure is returned, but no error message is reported.

Reimplemented from GDALRasterBand.

◆ SetColorInterpretation()

CPLErr GDALPamRasterBand::SetColorInterpretation ( GDALColorInterp eColorInterp )

overridevirtual

Set color interpretation of a band.

This method is the same as the C function GDALSetRasterColorInterpretation().

Parameters

eColorInterp the new color interpretation to apply to this band.

Returns: CE_None on success or CE_Failure if method is unsupported by format.

Reimplemented from GDALRasterBand.

◆ SetColorTable()

CPLErr GDALPamRasterBand::SetColorTable ( GDALColorTable * poCT )

overridevirtual

Set the raster color table.

The driver will make a copy of all desired data in the colortable. It remains owned by the caller after the call.

This method is the same as the C function GDALSetRasterColorTable().

Parameters

poCT	the color table to apply. This may be NULL to clear the color table (where supported).

Returns: CE_None on success, or CE_Failure on failure. If the action is unsupported by the driver, a value of CE_Failure is returned, but no error is issued.

Reimplemented from GDALRasterBand.

◆ SetDefaultHistogram()

CPLErr GDALPamRasterBand::SetDefaultHistogram	(	double	dfMin,
		double	dfMax,
		int	nBuckets,
		GUIntBig *	panHistogram
	)

overridevirtual

Set default histogram.

This method is the same as the C function GDALSetDefaultHistogram() and GDALSetDefaultHistogramEx()

Reimplemented from GDALRasterBand.

◆ SetDefaultRAT()

CPLErr GDALPamRasterBand::SetDefaultRAT ( const GDALRasterAttributeTable * poRAT )

overridevirtual

Set default Raster Attribute Table.

Associates a default RAT with the band. If not implemented for the format a CPLE_NotSupported error will be issued. If successful a copy of the RAT is made, the original remains owned by the caller.

This method is the same as the C function GDALSetDefaultRAT().

Parameters

poRAT the RAT to assign to the band.

Returns: CE_None on success or CE_Failure if unsupported or otherwise failing.

Reimplemented from GDALRasterBand.

◆ SetDescription()

void GDALPamRasterBand::SetDescription ( const char * pszNewDesc )

overridevirtual

Set object description.

The semantics of the description are specific to the derived type. For GDALDatasets it is the dataset name. For GDALRasterBands it is actually a description (if supported) or "".

Normally application code should not set the "description" for GDALDatasets. It is handled internally.

This method is the same as the C function GDALSetDescription().

Reimplemented from GDALMajorObject.

◆ SetMetadata()

CPLErr GDALPamRasterBand::SetMetadata	(	char **	papszMetadataIn,
		const char *	pszDomain = `""`
	)

overridevirtual

Set metadata.

The C function GDALSetMetadata() does the same thing as this method.

Parameters

papszMetadataIn	the metadata in name=value string list format to apply.
pszDomain	the domain of interest. Use "" or NULL for the default domain.

Returns: CE_None on success, CE_Failure on failure and CE_Warning if the metadata has been accepted, but is likely not maintained persistently by the underlying object between sessions.

Reimplemented from GDALMajorObject.

◆ SetMetadataItem()

CPLErr GDALPamRasterBand::SetMetadataItem	(	const char *	pszName,
		const char *	pszValue,
		const char *	pszDomain = `""`
	)

overridevirtual

Set single metadata item.

The C function GDALSetMetadataItem() does the same thing as this method.

Parameters

pszName	the key for the metadata item to fetch.
pszValue	the value to assign to the key.
pszDomain	the domain to set within, use NULL for the default domain.

Returns: CE_None on success, or an error code on failure.

Reimplemented from GDALMajorObject.

◆ SetMOFlags()

void GDALMajorObject::SetMOFlags ( int nNewFlags )

inherited

Assign GMO_flags.

Parameters

nNewFlags new flags.

◆ SetNoDataValue()

CPLErr GDALPamRasterBand::SetNoDataValue ( double dfNoData )

overridevirtual

Set the no data value for this band.

Depending on drivers, changing the no data value may or may not have an effect on the pixel values of a raster that has just been created. It is thus advised to explicitly called Fill() if the intent is to initialize the raster to the nodata value. In any case, changing an existing no data value, when one already exists and the dataset exists or has been initialized, has no effect on the pixel whose value matched the previous nodata value.

For rasters of type GDT_Int64 or GDT_UInt64, whose nodata value cannot always be represented by a double, use SetNoDataValueAsInt64() or SetNoDataValueAsUInt64() instead.

To clear the nodata value, use DeleteNoDataValue().

This method is the same as the C function GDALSetRasterNoDataValue().

Parameters

dfNoData the value to set.

Returns: CE_None on success, or CE_Failure on failure. If unsupported by the driver, CE_Failure is returned by no error message will have been emitted.

Reimplemented from GDALRasterBand.

◆ SetNoDataValueAsInt64()

CPLErr GDALPamRasterBand::SetNoDataValueAsInt64 ( int64_t nNoDataValue )

overridevirtual

Set the no data value for this band.

This method should ONLY be called on rasters whose data type is GDT_Int64.

Depending on drivers, changing the no data value may or may not have an effect on the pixel values of a raster that has just been created. It is thus advised to explicitly called Fill() if the intent is to initialize the raster to the nodata value. In ay case, changing an existing no data value, when one already exists and the dataset exists or has been initialized, has no effect on the pixel whose value matched the previous nodata value.

To clear the nodata value, use DeleteNoDataValue().

This method is the same as the C function GDALSetRasterNoDataValueAsInt64().

Parameters

nNoDataValue the value to set.

Returns: CE_None on success, or CE_Failure on failure. If unsupported by the driver, CE_Failure is returned by no error message will have been emitted.

Since: GDAL 3.5

Reimplemented from GDALRasterBand.

◆ SetNoDataValueAsUInt64()

CPLErr GDALPamRasterBand::SetNoDataValueAsUInt64 ( uint64_t nNoDataValue )

overridevirtual

Set the no data value for this band.

This method should ONLY be called on rasters whose data type is GDT_UInt64.

Depending on drivers, changing the no data value may or may not have an effect on the pixel values of a raster that has just been created. It is thus advised to explicitly called Fill() if the intent is to initialize the raster to the nodata value. In ay case, changing an existing no data value, when one already exists and the dataset exists or has been initialized, has no effect on the pixel whose value matched the previous nodata value.

To clear the nodata value, use DeleteNoDataValue().

This method is the same as the C function GDALSetRasterNoDataValueAsUInt64().

Parameters

nNoDataValue the value to set.

Returns: CE_None on success, or CE_Failure on failure. If unsupported by the driver, CE_Failure is returned by no error message will have been emitted.

Since: GDAL 3.5

Reimplemented from GDALRasterBand.

◆ SetOffset()

CPLErr GDALPamRasterBand::SetOffset ( double dfNewOffset )

overridevirtual

Set scaling offset.

Very few formats implement this method. When not implemented it will issue a CPLE_NotSupported error and return CE_Failure.

This method is the same as the C function GDALSetRasterOffset().

Parameters

dfNewOffset the new offset.

Returns: CE_None or success or CE_Failure on failure.

Reimplemented from GDALRasterBand.

◆ SetScale()

CPLErr GDALPamRasterBand::SetScale ( double dfNewScale )

overridevirtual

Set scaling ratio.

Very few formats implement this method. When not implemented it will issue a CPLE_NotSupported error and return CE_Failure.

This method is the same as the C function GDALSetRasterScale().

Parameters

dfNewScale the new scale.

Returns: CE_None or success or CE_Failure on failure.

Reimplemented from GDALRasterBand.

◆ SetStatistics()

CPLErr GDALRasterBand::SetStatistics	(	double	dfMin,
		double	dfMax,
		double	dfMean,
		double	dfStdDev
	)

virtualinherited

Set statistics on band.

This method can be used to store min/max/mean/standard deviation statistics on a raster band.

The default implementation stores them as metadata, and will only work on formats that can save arbitrary metadata. This method cannot detect whether metadata will be properly saved and so may return CE_None even if the statistics will never be saved.

This method is the same as the C function GDALSetRasterStatistics().

Parameters

dfMin	minimum pixel value.
dfMax	maximum pixel value.
dfMean	mean (average) of all pixel values.
dfStdDev	Standard deviation of all pixel values.

Returns: CE_None on success or CE_Failure on failure.

◆ SetUnitType()

CPLErr GDALPamRasterBand::SetUnitType ( const char * pszNewValue )

overridevirtual

Set unit type.

Set the unit type for a raster band. Values should be one of "" (the default indicating it is unknown), "m" indicating meters, or "ft" indicating feet, though other nonstandard values are allowed.

This method is the same as the C function GDALSetRasterUnitType().

Parameters

pszNewValue the new unit type value.

Returns: CE_None on success or CE_Failure if not successful, or unsupported.

Reimplemented from GDALRasterBand.

◆ ToHandle() [1/2]

static GDALMajorObjectH GDALMajorObject::ToHandle ( GDALMajorObject * poMajorObject )

inlinestaticinherited

Convert a GDALMajorObject* to a GDALMajorObjectH.

Since: GDAL 2.3

◆ ToHandle() [2/2]

void static GDALRasterBandH GDALRasterBand::ToHandle ( GDALRasterBand * poBand )

inlinestaticinherited

Convert a GDALRasterBand* to a GDALRasterBandH.

Since: GDAL 2.3

◆ TryGetLockedBlockRef()

GDALRasterBlock * GDALRasterBand::TryGetLockedBlockRef	(	int	nXBlockOff,
		int	nYBlockOff
	)

inherited

Try fetching block ref.

This method will returned the requested block (locked) if it is already in the block cache for the layer. If not, nullptr is returned.

If a non-NULL value is returned, then a lock for the block will have been acquired on behalf of the caller. It is absolutely imperative that the caller release this lock (with GDALRasterBlock::DropLock()) or else severe problems may result.

Parameters

nXBlockOff	the horizontal block offset, with zero indicating the left most block, 1 the next block and so forth.
nYBlockOff	the vertical block offset, with zero indicating the top most block, 1 the next block and so forth.

Returns: NULL if block not available, or locked block pointer.

◆ WriteBlock()

CPLErr GDALRasterBand::WriteBlock	(	int	nXBlockOff,
		int	nYBlockOff,
		void *	pImage
	)

inherited

Write a block of image data efficiently.

This method accesses a "natural" block from the raster band without resampling, or data type conversion. For a more generalized, but potentially less efficient access use RasterIO().

This method is the same as the C GDALWriteBlock() function.

See ReadBlock() for an example of block oriented data access.

Parameters

nXBlockOff	the horizontal block offset, with zero indicating the left most block, 1 the next block and so forth.
nYBlockOff	the vertical block offset, with zero indicating the left most block, 1 the next block and so forth.
pImage	the buffer from which the data will be written. The buffer must be large enough to hold GetBlockXSize()*GetBlockYSize() words of type GetRasterDataType(). Note that the content of the buffer might be temporarily modified during the execution of this method (and eventually restored back to its original content), so it is not safe to use a buffer stored in a read-only section of the calling program.

Returns: CE_None on success or CE_Failure on an error.

The documentation for this class was generated from the following files:

gdal_pam.h
gdalpamrasterband.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Friends

Detailed Description

Member Function Documentation

◆ AdviseRead()

◆ AsMDArray()

◆ BuildMetadataDomainList()

◆ BuildOverviews()

◆ ComputeRasterMinMax()

◆ ComputeStatistics()

◆ CreateMaskBand()

◆ DeleteNoDataValue()

◆ DropCache()

◆ Fill()

◆ FlushBlock()

◆ FlushCache()

◆ FromHandle()

◆ GetAccess()

◆ GetActualBlockSize()

◆ GetBand()

◆ GetBlockSize()

◆ GetCategoryNames()

◆ GetColorInterpretation()

◆ GetColorTable()

◆ GetDataCoverageStatus()

◆ GetDataset()

◆ GetDefaultHistogram()

◆ GetDefaultRAT()

◆ GetDescription()

◆ GetHistogram()

◆ GetIndexColorTranslationTo()

◆ GetLockedBlockRef()

◆ GetMaskBand()

◆ GetMaskFlags()

◆ GetMaskValueRange()

◆ GetMaximum()

◆ GetMetadata()

◆ GetMetadataDomainList()

◆ GetMetadataItem()

◆ GetMinimum()

◆ GetMOFlags()

◆ GetNoDataValue()

◆ GetNoDataValueAsInt64()

◆ GetNoDataValueAsUInt64()

◆ GetOffset()

◆ GetOverview()

◆ GetOverviewCount()

◆ GetRasterDataType()

◆ GetRasterSampleOverview()

◆ GetScale()

◆ GetStatistics()

◆ GetSuggestedBlockAccessPattern()

◆ GetUnitType()

◆ GetVirtualMemAuto()

◆ GetXSize()

◆ GetYSize()

◆ HasArbitraryOverviews()

◆ IGetDataCoverageStatus()

◆ IRasterIO()

◆ IReadBlock()

◆ IsMaskBand()

◆ IWriteBlock()

◆ RasterIO()

◆ ReadBlock()

◆ ReportError()

◆ SetCategoryNames()

◆ SetColorInterpretation()

◆ SetColorTable()

◆ SetDefaultHistogram()

◆ SetDefaultRAT()

◆ SetDescription()

◆ SetMetadata()

◆ SetMetadataItem()

◆ SetMOFlags()

◆ SetNoDataValue()

◆ SetNoDataValueAsInt64()

◆ SetNoDataValueAsUInt64()

◆ SetOffset()