QGIS API Documentation  3.21.0-Master (56b4176581)
qgsrasterdataprovider.h
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1 /***************************************************************************
2  qgsrasterdataprovider.h - DataProvider Interface for raster layers
3  --------------------------------------
4  Date : Mar 11, 2005
5  Copyright : (C) 2005 by Brendan Morley
6  email : morb at ozemail dot com dot au
7 
8  async legend fetcher : Sandro Santilli < strk at keybit dot net >
9 
10  ***************************************************************************/
11 
12 /***************************************************************************
13  * *
14  * This program is free software; you can redistribute it and/or modify *
15  * it under the terms of the GNU General Public License as published by *
16  * the Free Software Foundation; either version 2 of the License, or *
17  * (at your option) any later version. *
18  * *
19  ***************************************************************************/
20 
21 /* Thank you to Marco Hugentobler for the original vector DataProvider */
22 
23 #ifndef QGSRASTERDATAPROVIDER_H
24 #define QGSRASTERDATAPROVIDER_H
25 
26 #include "qgis_core.h"
27 #include "qgis_sip.h"
28 #include <cmath>
29 
30 #include <QDateTime>
31 #include <QVariant>
32 #include <QImage>
33 
34 #include "qgscolorrampshader.h"
35 #include "qgsdataprovider.h"
36 #include "qgsraster.h"
37 #include "qgsfields.h"
38 #include "qgsrasterinterface.h"
39 #include "qgsrasterpyramid.h"
40 #include "qgsrasterrange.h"
41 #include "qgsrectangle.h"
42 #include "qgsrasteriterator.h"
44 
45 class QImage;
46 class QByteArray;
47 
48 class QgsPointXY;
50 class QgsMapSettings;
51 
57 class CORE_EXPORT QgsImageFetcher : public QObject
58 {
59  Q_OBJECT
60  public:
62  QgsImageFetcher( QObject *parent = nullptr ) : QObject( parent ) {}
63 
68  virtual void start() = 0;
69 
70  signals:
71 
76  void finish( const QImage &legend );
78  void progress( qint64 received, qint64 total );
80  void error( const QString &msg );
81 };
82 
83 
88 class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRasterInterface
89 {
90  Q_OBJECT
91 
92  public:
93 
99  {
100  NoProviderCapabilities = 0,
101  ReadLayerMetadata = 1 << 1,
102  WriteLayerMetadata = 1 << 2,
103  ProviderHintBenefitsFromResampling = 1 << 3,
104  ProviderHintCanPerformProviderResampling = 1 << 4,
105  ReloadData = 1 << 5,
106  DpiDependentData = 1 << 6,
107  };
108 
110  Q_DECLARE_FLAGS( ProviderCapabilities, ProviderCapability )
111 
113 
122  QgsRasterDataProvider( const QString &uri,
124  QgsDataProvider::ReadFlags flags = QgsDataProvider::ReadFlags() );
125 
126  QgsRasterDataProvider *clone() const override = 0;
127 
132  virtual QgsRasterDataProvider::ProviderCapabilities providerCapabilities() const;
133 
134  /* It makes no sense to set input on provider */
135  bool setInput( QgsRasterInterface *input ) override { Q_UNUSED( input ) return false; }
136 
137  QgsRectangle extent() const override = 0;
138 
140  Qgis::DataType dataType( int bandNo ) const override = 0;
141 
147  virtual QgsFields fields() const { return QgsFields(); };
148 
153  Qgis::DataType sourceDataType( int bandNo ) const override = 0;
154 
156  virtual int colorInterpretation( int bandNo ) const;
157 
158  QString colorName( int colorInterpretation ) const
159  {
160  // Modified copy from GDAL
161  switch ( colorInterpretation )
162  {
164  return QStringLiteral( "Undefined" );
165 
167  return QStringLiteral( "Gray" );
168 
170  return QStringLiteral( "Palette" );
171 
172  case QgsRaster::RedBand:
173  return QStringLiteral( "Red" );
174 
176  return QStringLiteral( "Green" );
177 
178  case QgsRaster::BlueBand:
179  return QStringLiteral( "Blue" );
180 
182  return QStringLiteral( "Alpha" );
183 
184  case QgsRaster::HueBand:
185  return QStringLiteral( "Hue" );
186 
188  return QStringLiteral( "Saturation" );
189 
191  return QStringLiteral( "Lightness" );
192 
193  case QgsRaster::CyanBand:
194  return QStringLiteral( "Cyan" );
195 
197  return QStringLiteral( "Magenta" );
198 
200  return QStringLiteral( "Yellow" );
201 
203  return QStringLiteral( "Black" );
204 
206  return QStringLiteral( "YCbCr_Y" );
207 
209  return QStringLiteral( "YCbCr_Cb" );
210 
212  return QStringLiteral( "YCbCr_Cr" );
213 
214  default:
215  return QStringLiteral( "Unknown" );
216  }
217  }
219  virtual bool reload() { return true; }
220 
221  QString colorInterpretationName( int bandNo ) const override;
222 
227  virtual double bandScale( int bandNo ) const { Q_UNUSED( bandNo ) return 1.0; }
228 
233  virtual double bandOffset( int bandNo ) const { Q_UNUSED( bandNo ) return 0.0; }
234 
235  // TODO: remove or make protected all readBlock working with void*
236 
238  QgsRasterBlock *block( int bandNo, const QgsRectangle &boundingBox, int width, int height, QgsRasterBlockFeedback *feedback = nullptr ) override SIP_FACTORY;
239 
241  virtual bool sourceHasNoDataValue( int bandNo ) const { return mSrcHasNoDataValue.value( bandNo - 1 ); }
242 
244  virtual bool useSourceNoDataValue( int bandNo ) const { return mUseSrcNoDataValue.value( bandNo - 1 ); }
245 
247  virtual void setUseSourceNoDataValue( int bandNo, bool use );
248 
250  virtual double sourceNoDataValue( int bandNo ) const { return mSrcNoDataValue.value( bandNo - 1 ); }
251 
252  virtual void setUserNoDataValue( int bandNo, const QgsRasterRangeList &noData );
253 
255  virtual QgsRasterRangeList userNoDataValues( int bandNo ) const { return mUserNoDataValue.value( bandNo - 1 ); }
256 
257  virtual QList<QgsColorRampShader::ColorRampItem> colorTable( int bandNo ) const
258  { Q_UNUSED( bandNo ) return QList<QgsColorRampShader::ColorRampItem>(); }
259 
264  QStringList subLayers() const override
265  {
266  return QStringList();
267  }
268 
269  QgsRasterDataProviderTemporalCapabilities *temporalCapabilities() override;
270  const QgsRasterDataProviderTemporalCapabilities *temporalCapabilities() const override SIP_SKIP;
271 
273  virtual bool supportsLegendGraphic() const { return false; }
274 
286  virtual QImage getLegendGraphic( double scale = 0, bool forceRefresh = false, const QgsRectangle *visibleExtent = nullptr ) SIP_SKIP
287  {
288  Q_UNUSED( scale )
289  Q_UNUSED( forceRefresh )
290  Q_UNUSED( visibleExtent )
291  return QImage();
292  }
293 
308  {
309  Q_UNUSED( mapSettings )
310  return nullptr;
311  }
312 
329  virtual QString buildPyramids( const QList<QgsRasterPyramid> &pyramidList,
330  const QString &resamplingMethod = "NEAREST",
332  const QStringList &configOptions = QStringList(),
333  QgsRasterBlockFeedback *feedback = nullptr )
334  {
335  Q_UNUSED( pyramidList )
336  Q_UNUSED( resamplingMethod )
337  Q_UNUSED( format )
338  Q_UNUSED( configOptions )
339  Q_UNUSED( feedback )
340  return QStringLiteral( "FAILED_NOT_SUPPORTED" );
341  }
342 
361  virtual QList<QgsRasterPyramid> buildPyramidList( const QList<int> &overviewList = QList<int>() )
362  { Q_UNUSED( overviewList ) return QList<QgsRasterPyramid>(); }
363 
373  bool hasPyramids();
374 
379  virtual QString htmlMetadata() = 0;
380 
405  virtual QgsRasterIdentifyResult identify( const QgsPointXY &point, QgsRaster::IdentifyFormat format, const QgsRectangle &boundingBox = QgsRectangle(), int width = 0, int height = 0, int dpi = 96 );
406 
421  virtual double sample( const QgsPointXY &point, int band,
422  bool *ok SIP_OUT = nullptr,
423  const QgsRectangle &boundingBox = QgsRectangle(), int width = 0, int height = 0, int dpi = 96 );
424 
433  virtual QString lastErrorTitle() = 0;
434 
444  virtual QString lastError() = 0;
445 
447  virtual QString lastErrorFormat();
448 
450  int dpi() const { return mDpi; }
451 
453  void setDpi( int dpi ) { mDpi = dpi; }
454 
456  QDateTime timestamp() const override { return mTimestamp; }
457 
459  QDateTime dataTimestamp() const override { return QDateTime(); }
460 
467  virtual bool isEditable() const { return false; }
468 
479  virtual bool setEditable( bool enabled ) { Q_UNUSED( enabled ) return false; }
480 
481  // TODO: add data type (may be different from band type)
482 
484  virtual bool write( void *data, int band, int width, int height, int xOffset, int yOffset )
485  {
486  Q_UNUSED( data )
487  Q_UNUSED( band )
488  Q_UNUSED( width )
489  Q_UNUSED( height )
490  Q_UNUSED( xOffset )
491  Q_UNUSED( yOffset )
492  return false;
493  }
494 
511  bool writeBlock( QgsRasterBlock *block, int band, int xOffset = 0, int yOffset = 0 );
512 
514  static QgsRasterDataProvider *create( const QString &providerKey,
515  const QString &uri,
516  const QString &format, int nBands,
517  Qgis::DataType type,
518  int width, int height, double *geoTransform,
520  const QStringList &createOptions = QStringList() );
521 
527  virtual bool setNoDataValue( int bandNo, double noDataValue ) { Q_UNUSED( bandNo ) Q_UNUSED( noDataValue ); return false; }
528 
530  virtual bool remove() { return false; }
531 
536  static QList<QPair<QString, QString> > pyramidResamplingMethods( const QString &providerKey );
537 
544  {
545  QString name;
546  QString uri;
547  QString provider;
548  };
549 
556  {
559  int width;
560  int height;
561  QString formula;
562  QList <QgsRasterDataProvider::VirtualRasterInputLayers> rInputLayers;
563 
564  };
565 
571  static QgsRasterDataProvider::VirtualRasterParameters decodeVirtualRasterProviderUri( const QString &uri, bool *ok = nullptr );
572 
578  static QString encodeVirtualRasterProviderUri( const VirtualRasterParameters &parts );
579 
585  virtual QString validateCreationOptions( const QStringList &createOptions, const QString &format )
586  { Q_UNUSED( createOptions ) Q_UNUSED( format ); return QString(); }
587 
593  const QStringList &configOptions, const QString &fileFormat )
594  { Q_UNUSED( pyramidsFormat ) Q_UNUSED( configOptions ); Q_UNUSED( fileFormat ); return QString(); }
595 
596  static QString identifyFormatName( QgsRaster::IdentifyFormat format );
597  static QgsRaster::IdentifyFormat identifyFormatFromName( const QString &formatName );
598  static QString identifyFormatLabel( QgsRaster::IdentifyFormat format );
599  static Capability identifyFormatToCapability( QgsRaster::IdentifyFormat format );
600 
607 
614 
623  virtual QList< double > nativeResolutions() const;
624 
631  virtual bool ignoreExtents() const;
632 
638  {
641  };
642 
655  virtual QgsPoint transformCoordinates( const QgsPoint &point, TransformType type );
656 
657 
664  virtual bool enableProviderResampling( bool enable ) { Q_UNUSED( enable ); return false; }
665 
678  bool isProviderResamplingEnabled() const { return mProviderResamplingEnabled; }
679 
684  enum class ResamplingMethod
685  {
686  Nearest,
687  Bilinear,
688  Cubic,
689  CubicSpline,
690  Lanczos,
691  Average,
692  Mode,
693  Gauss
694  };
695 
702  virtual bool setZoomedInResamplingMethod( ResamplingMethod method ) { Q_UNUSED( method ); return false; }
703 
708  ResamplingMethod zoomedInResamplingMethod() const { return mZoomedInResamplingMethod; }
709 
716  virtual bool setZoomedOutResamplingMethod( ResamplingMethod method ) { Q_UNUSED( method ); return false; }
717 
722  ResamplingMethod zoomedOutResamplingMethod() const { return mZoomedOutResamplingMethod; }
723 
730  virtual bool setMaxOversampling( double factor ) { Q_UNUSED( factor ); return false; }
731 
736  double maxOversampling() const { return mMaxOversampling; }
737 
738  void readXml( const QDomElement &filterElem ) override;
739 
740  void writeXml( QDomDocument &doc, QDomElement &parentElem ) const override;
741 
742  signals:
743 
748  void statusChanged( const QString & ) const;
749 
750  protected:
751 
757  virtual bool readBlock( int bandNo, int xBlock, int yBlock, void *data ) SIP_SKIP
758  { Q_UNUSED( bandNo ) Q_UNUSED( xBlock ); Q_UNUSED( yBlock ); Q_UNUSED( data ); return false; }
759 
765  virtual bool readBlock( int bandNo, QgsRectangle const &viewExtent, int width, int height, void *data, QgsRasterBlockFeedback *feedback = nullptr ) SIP_SKIP
766  { Q_UNUSED( bandNo ) Q_UNUSED( viewExtent ); Q_UNUSED( width ); Q_UNUSED( height ); Q_UNUSED( data ); Q_UNUSED( feedback ); return false; }
767 
769  bool userNoDataValuesContains( int bandNo, double value ) const;
770 
772  void copyBaseSettings( const QgsRasterDataProvider &other );
773 
778  int mDpi = -1;
779 
784  //bool hasNoDataValue ( int bandNo );
785 
787  QList<double> mSrcNoDataValue;
788 
790  QList<bool> mSrcHasNoDataValue;
791 
797  QList<bool> mUseSrcNoDataValue;
798 
803  QList< QgsRasterRangeList > mUserNoDataValue;
804 
806 
808  bool mProviderResamplingEnabled = false;
809 
811  ResamplingMethod mZoomedInResamplingMethod = ResamplingMethod::Nearest;
812 
814  ResamplingMethod mZoomedOutResamplingMethod = ResamplingMethod::Nearest;
815 
817  double mMaxOversampling = 2.0;
818 
819  private:
820 
824  std::unique_ptr< QgsRasterDataProviderTemporalCapabilities > mTemporalCapabilities;
825 
826 };
827 
828 Q_DECLARE_OPERATORS_FOR_FLAGS( QgsRasterDataProvider::ProviderCapabilities )
829 
830 // clazy:excludeall=qstring-allocations
831 
832 #endif
DataType
Raster data types.
Definition: qgis.h:120
This class represents a coordinate reference system (CRS).
Abstract base class for spatial data provider implementations.
Container of fields for a vector layer.
Definition: qgsfields.h:45
Handles asynchronous download of images.
QgsImageFetcher(QObject *parent=nullptr)
Constructor.
void progress(qint64 received, qint64 total)
Emitted to report progress.
void error(const QString &msg)
Emitted when an error occurs.
void finish(const QImage &legend)
Emitted when the download completes.
virtual void start()=0
Starts the image download.
The QgsMapSettings class contains configuration for rendering of the map.
A class to represent a 2D point.
Definition: qgspointxy.h:59
Point geometry type, with support for z-dimension and m-values.
Definition: qgspoint.h:49
Feedback object tailored for raster block reading.
Raster data container.
Implementation of data provider temporal properties for QgsRasterDataProviders.
Base class for raster data providers.
virtual QgsFields fields() const
Returns the fields of the raster layer for data providers that expose them, the default implementatio...
virtual QString buildPyramids(const QList< QgsRasterPyramid > &pyramidList, const QString &resamplingMethod="NEAREST", QgsRaster::RasterPyramidsFormat format=QgsRaster::PyramidsGTiff, const QStringList &configOptions=QStringList(), QgsRasterBlockFeedback *feedback=nullptr)
Creates pyramid overviews.
QList< bool > mUseSrcNoDataValue
Use source nodata value.
TransformType
Types of transformation in transformCoordinates() function.
@ TransformLayerToImage
Transforms layer (georeferenced) coordinates to image coordinates.
@ TransformImageToLayer
Transforms image coordinates to layer (georeferenced) coordinates.
virtual QList< QgsColorRampShader::ColorRampItem > colorTable(int bandNo) const
virtual bool setNoDataValue(int bandNo, double noDataValue)
Set no data value on created dataset.
virtual double bandOffset(int bandNo) const
Read band offset for raster value.
virtual bool readBlock(int bandNo, QgsRectangle const &viewExtent, int width, int height, void *data, QgsRasterBlockFeedback *feedback=nullptr)
Reads a block of raster data into data, using the given extent and size.
virtual bool useSourceNoDataValue(int bandNo) const
Returns the source nodata value usage.
virtual QString validateCreationOptions(const QStringList &createOptions, const QString &format)
Validates creation options for a specific dataset and destination format.
virtual QString lastError()=0
Returns the verbose error text for the last error in this provider.
virtual QList< QgsRasterPyramid > buildPyramidList(const QList< int > &overviewList=QList< int >())
Returns the raster layers pyramid list.
Qgis::DataType sourceDataType(int bandNo) const override=0
Returns source data type for the band specified by number, source data type may be shorter than dataT...
bool isProviderResamplingEnabled() const
Returns whether provider-level resampling is enabled.
virtual bool remove()
Remove dataset.
virtual double sourceNoDataValue(int bandNo) const
Value representing no data value.
QString colorName(int colorInterpretation) const
virtual QImage getLegendGraphic(double scale=0, bool forceRefresh=false, const QgsRectangle *visibleExtent=nullptr)
Returns the legend rendered as pixmap.
virtual bool reload()
Reload data (data could change)
QList< QgsRasterRangeList > mUserNoDataValue
List of lists of user defined additional no data values for each band, indexed from 0.
ResamplingMethod zoomedOutResamplingMethod() const
Returns resampling method for zoomed-out operations.
virtual bool isEditable() const
Checks whether the provider is in editing mode, i.e.
QgsRasterDataProvider * clone() const override=0
Clone itself, create deep copy.
virtual bool enableProviderResampling(bool enable)
Enable or disable provider-level resampling.
void setDpi(int dpi)
Sets the output device resolution.
QDateTime timestamp() const override
Time stamp of data source in the moment when data/metadata were loaded by provider.
QgsRectangle extent() const override=0
Returns the extent of the layer.
virtual bool setMaxOversampling(double factor)
Sets maximum oversampling factor for zoomed-out operations.
Qgis::DataType dataType(int bandNo) const override=0
Returns data type for the band specified by number.
double maxOversampling() const
Returns maximum oversampling factor for zoomed-out operations.
QStringList subLayers() const override
Returns the sublayers of this layer - useful for providers that manage their own layers,...
virtual double bandScale(int bandNo) const
Read band scale for raster value.
ProviderCapability
Enumeration with capabilities that raster providers might implement.
int dpi() const
Returns the dpi of the output device.
virtual QString validatePyramidsConfigOptions(QgsRaster::RasterPyramidsFormat pyramidsFormat, const QStringList &configOptions, const QString &fileFormat)
Validates pyramid creation options for a specific dataset and destination format.
QDateTime dataTimestamp() const override
Current time stamp of data source.
virtual QString htmlMetadata()=0
Returns metadata in a format suitable for feeding directly into a subset of the GUI raster properties...
QList< double > mSrcNoDataValue
Source no data value is available and is set to be used or internal no data is available.
virtual bool readBlock(int bandNo, int xBlock, int yBlock, void *data)
Reads a block of raster data into data.
bool setInput(QgsRasterInterface *input) override
Set input.
QList< bool > mSrcHasNoDataValue
Source no data value exists.
void statusChanged(const QString &) const
Emit a message to be displayed on status bar, usually used by network providers (WMS,...
virtual QgsRasterRangeList userNoDataValues(int bandNo) const
Returns a list of user no data value ranges.
virtual bool setZoomedInResamplingMethod(ResamplingMethod method)
Set resampling method to apply for zoomed-in operations.
virtual int stepHeight() const
Step height for raster iterations.
virtual bool setEditable(bool enabled)
Turns on/off editing mode of the provider.
virtual int stepWidth() const
Step width for raster iterations.
ResamplingMethod zoomedInResamplingMethod() const
Returns resampling method for zoomed-in operations.
ResamplingMethod
Resampling method for provider-level resampling.
virtual QString lastErrorTitle()=0
Returns the caption error text for the last error in this provider.
virtual bool write(void *data, int band, int width, int height, int xOffset, int yOffset)
Writes into the provider datasource.
virtual bool setZoomedOutResamplingMethod(ResamplingMethod method)
Set resampling method to apply for zoomed-out operations.
virtual QgsImageFetcher * getLegendGraphicFetcher(const QgsMapSettings *mapSettings)
Returns a new image downloader for the raster legend.
Raster identify results container.
Base class for processing filters like renderers, reprojector, resampler etc.
static const int DEFAULT_MAXIMUM_TILE_WIDTH
Default maximum tile width.
static const int DEFAULT_MAXIMUM_TILE_HEIGHT
Default maximum tile height.
IdentifyFormat
Definition: qgsraster.h:58
RasterPyramidsFormat
Definition: qgsraster.h:82
@ PyramidsGTiff
Definition: qgsraster.h:83
@ RedBand
Red band of RGBA image.
Definition: qgsraster.h:40
@ UndefinedColorInterpretation
Definition: qgsraster.h:37
@ YCbCr_YBand
Y Luminance.
Definition: qgsraster.h:51
@ YellowBand
Yellow band of CMYK image.
Definition: qgsraster.h:49
@ YCbCr_CbBand
Cb Chroma.
Definition: qgsraster.h:52
@ BlueBand
Blue band of RGBA image.
Definition: qgsraster.h:42
@ PaletteIndex
Paletted (see associated color table)
Definition: qgsraster.h:39
@ HueBand
Hue band of HLS image.
Definition: qgsraster.h:44
@ LightnessBand
Lightness band of HLS image.
Definition: qgsraster.h:46
@ AlphaBand
Alpha (0=transparent, 255=opaque)
Definition: qgsraster.h:43
@ BlackBand
Black band of CMLY image.
Definition: qgsraster.h:50
@ GreenBand
Green band of RGBA image.
Definition: qgsraster.h:41
@ CyanBand
Cyan band of CMYK image.
Definition: qgsraster.h:47
@ SaturationBand
Saturation band of HLS image.
Definition: qgsraster.h:45
@ GrayIndex
Greyscale.
Definition: qgsraster.h:38
@ MagentaBand
Magenta band of CMYK image.
Definition: qgsraster.h:48
@ YCbCr_CrBand
Cr Chroma.
Definition: qgsraster.h:53
A rectangle specified with double values.
Definition: qgsrectangle.h:42
#define SIP_SKIP
Definition: qgis_sip.h:126
#define SIP_OUT
Definition: qgis_sip.h:58
#define SIP_FACTORY
Definition: qgis_sip.h:76
Q_DECLARE_OPERATORS_FOR_FLAGS(QgsField::ConfigurationFlags) CORE_EXPORT QDataStream &operator<<(QDataStream &out
Writes the field to stream out. QGIS version compatibility is not guaranteed.
QList< QgsRasterRange > QgsRasterRangeList
const QgsCoordinateReferenceSystem & crs
Setting options for creating vector data providers.
Struct that stores information of the raster used in QgsVirtualRasterProvider for the calculations,...
Struct that stores the information about the parameters that should be given to the QgsVirtualRasterP...
QList< QgsRasterDataProvider::VirtualRasterInputLayers > rInputLayers