QGIS API Documentation 3.39.0-Master (67e056379ed)
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qgsalgorithmfillnodata.cpp
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1/***************************************************************************
2 qgsalgorithmfillnodata.cpp
3 ---------------------
4 begin : January 2020
5 copyright : (C) 2020 by Clemens Raffler
6 email : clemens dot raffler at gmail dot com
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
19#include "qgsrasterfilewriter.h"
20
22
23QString QgsFillNoDataAlgorithm::name() const
24{
25 return QStringLiteral( "fillnodata" );
26}
27
28QString QgsFillNoDataAlgorithm::displayName() const
29{
30 return QObject::tr( "Fill NoData cells" );
31}
32
33QStringList QgsFillNoDataAlgorithm::tags() const
34{
35 return QObject::tr( "data,cells,fill,set" ).split( ',' );
36}
37
38QString QgsFillNoDataAlgorithm::group() const
39{
40 return QObject::tr( "Raster tools" );
41}
42
43QString QgsFillNoDataAlgorithm::groupId() const
44{
45 return QStringLiteral( "rastertools" );
46}
47
48void QgsFillNoDataAlgorithm::initAlgorithm( const QVariantMap & )
49{
50 addParameter( new QgsProcessingParameterRasterLayer( QStringLiteral( "INPUT" ), QStringLiteral( "Raster input" ) ) );
51 addParameter( new QgsProcessingParameterBand( QStringLiteral( "BAND" ), QObject::tr( "Band Number" ), 1, QStringLiteral( "INPUT" ) ) );
52 addParameter( new QgsProcessingParameterNumber( QStringLiteral( "FILL_VALUE" ), QObject::tr( "Fill value" ), Qgis::ProcessingNumberParameterType::Double, 1, false ) );
53
54 std::unique_ptr< QgsProcessingParameterString > createOptsParam = std::make_unique< QgsProcessingParameterString >( QStringLiteral( "CREATE_OPTIONS" ), QObject::tr( "Creation options" ), QVariant(), false, true );
55 createOptsParam->setMetadata( QVariantMap( {{QStringLiteral( "widget_wrapper" ), QVariantMap( {{QStringLiteral( "widget_type" ), QStringLiteral( "rasteroptions" ) }} ) }} ) );
56 createOptsParam->setFlags( createOptsParam->flags() | Qgis::ProcessingParameterFlag::Advanced );
57 addParameter( createOptsParam.release() );
58
59 addParameter( new QgsProcessingParameterRasterDestination( QStringLiteral( "OUTPUT" ), QObject::tr( "Output raster" ) ) );
60}
61
62QString QgsFillNoDataAlgorithm::shortHelpString() const
63{
64 return QObject::tr( "This algorithm resets the NoData values in the input raster "
65 "to a chosen value, resulting in a raster dataset with no NoData pixels. "
66 "This value can be set by the user using the Fill value parameter. "
67 "The algorithm respects the input raster data type (eg. a floating point fill value will be truncated "
68 "when applied to an integer raster)." );
69}
70
71QgsFillNoDataAlgorithm *QgsFillNoDataAlgorithm::createInstance() const
72{
73 return new QgsFillNoDataAlgorithm();
74}
75
76bool QgsFillNoDataAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
77{
78 Q_UNUSED( feedback );
79 mInputRaster = parameterAsRasterLayer( parameters, QStringLiteral( "INPUT" ), context );
80 mFillValue = parameterAsDouble( parameters, QStringLiteral( "FILL_VALUE" ), context );
81
82 if ( !mInputRaster )
83 throw QgsProcessingException( invalidRasterError( parameters, QStringLiteral( "INPUT" ) ) );
84
85 mBand = parameterAsInt( parameters, QStringLiteral( "BAND" ), context );
86 if ( mBand < 1 || mBand > mInputRaster->bandCount() )
87 throw QgsProcessingException( QObject::tr( "Invalid band number for BAND (%1): Valid values for input raster are 1 to %2" ).arg( mBand ).arg( mInputRaster->bandCount() ) );
88
89 mInterface.reset( mInputRaster->dataProvider()->clone() );
90 mInputNoDataValue = mInputRaster->dataProvider()->sourceNoDataValue( mBand );
91 mExtent = mInputRaster->extent();
92 mLayerWidth = mInputRaster->width();
93 mLayerHeight = mInputRaster->height();
94 mCrs = mInputRaster->crs();
95 mNbCellsXProvider = mInterface->xSize();
96 mNbCellsYProvider = mInterface->ySize();
97 return true;
98}
99
100QVariantMap QgsFillNoDataAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
101{
102 //test if input dataset has NoData
103 if ( !mInputRaster->dataProvider()->sourceHasNoDataValue( mBand ) )
104 feedback->reportError( QObject::tr( "Input raster has no NoData values. There exist no NoData cells to fill." ), false );
105
106 //prepare output dataset
107 const QString createOptions = parameterAsString( parameters, QStringLiteral( "CREATE_OPTIONS" ), context ).trimmed();
108 const QString outputFile = parameterAsOutputLayer( parameters, QStringLiteral( "OUTPUT" ), context );
109 const QFileInfo fi( outputFile );
110 const QString outputFormat = QgsRasterFileWriter::driverForExtension( fi.suffix() );
111 std::unique_ptr< QgsRasterFileWriter > writer = std::make_unique< QgsRasterFileWriter >( outputFile );
112 writer->setOutputProviderKey( QStringLiteral( "gdal" ) );
113 if ( !createOptions.isEmpty() )
114 {
115 writer->setCreateOptions( createOptions.split( '|' ) );
116 }
117 writer->setOutputFormat( outputFormat );
118 std::unique_ptr<QgsRasterDataProvider > provider( writer->createOneBandRaster( mInterface->dataType( mBand ), mNbCellsXProvider, mNbCellsYProvider, mExtent, mCrs ) );
119 if ( !provider )
120 throw QgsProcessingException( QObject::tr( "Could not create raster output: %1" ).arg( outputFile ) );
121 if ( !provider->isValid() )
122 throw QgsProcessingException( QObject::tr( "Could not create raster output %1: %2" ).arg( outputFile, provider->error().message( QgsErrorMessage::Text ) ) );
123
124 //prepare output provider
125 QgsRasterDataProvider *destinationRasterProvider;
126 destinationRasterProvider = provider.get();
127 destinationRasterProvider->setEditable( true );
128
131 const int nbBlocksWidth = static_cast< int >( std::ceil( 1.0 * mLayerWidth / maxWidth ) );
132 const int nbBlocksHeight = static_cast< int >( std::ceil( 1.0 * mLayerHeight / maxHeight ) );
133 const int nbBlocks = nbBlocksWidth * nbBlocksHeight;
134
135 QgsRasterIterator iter( mInterface.get() );
136 iter.startRasterRead( mBand, mLayerWidth, mLayerHeight, mExtent );
137 int iterLeft = 0;
138 int iterTop = 0;
139 int iterCols = 0;
140 int iterRows = 0;
141 std::unique_ptr< QgsRasterBlock > filledRasterBlock;
142 while ( iter.readNextRasterPart( mBand, iterCols, iterRows, filledRasterBlock, iterLeft, iterTop ) )
143 {
144 if ( feedback )
145 feedback->setProgress( 100 * ( ( iterTop / maxHeight * nbBlocksWidth ) + iterLeft / maxWidth ) / nbBlocks );
146
147 if ( feedback && feedback->isCanceled() )
148 break;
149
150 if ( !filledRasterBlock->hasNoDataValue() )
151 {
152 destinationRasterProvider->writeBlock( filledRasterBlock.get(), mBand, iterLeft, iterTop );
153 continue;
154 }
155
156 for ( int row = 0; row < iterRows; row++ )
157 {
158 if ( feedback && feedback->isCanceled() )
159 break;
160 for ( int column = 0; column < iterCols; column++ )
161 {
162 if ( filledRasterBlock->isNoData( row, column ) )
163 filledRasterBlock->setValue( row, column, mFillValue );
164 }
165 }
166 destinationRasterProvider->writeBlock( filledRasterBlock.get(), mBand, iterLeft, iterTop );
167 }
168 destinationRasterProvider->setEditable( false );
169
170 QVariantMap outputs;
171 outputs.insert( QStringLiteral( "OUTPUT" ), outputFile );
172 return outputs;
173}
174
@ Advanced
Parameter is an advanced parameter which should be hidden from users by default.
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:53
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:61
Contains information about the context in which a processing algorithm is executed.
Custom exception class for processing related exceptions.
Base class for providing feedback from a processing algorithm.
virtual void reportError(const QString &error, bool fatalError=false)
Reports that the algorithm encountered an error while executing.
A raster band parameter for Processing algorithms.
A numeric parameter for processing algorithms.
A raster layer destination parameter, for specifying the destination path for a raster layer created ...
A raster layer parameter for processing algorithms.
Base class for raster data providers.
bool writeBlock(QgsRasterBlock *block, int band, int xOffset=0, int yOffset=0)
Writes pixel data from a raster block into the provider data source.
virtual bool setEditable(bool enabled)
Turns on/off editing mode of the provider.
static QString driverForExtension(const QString &extension)
Returns the GDAL driver name for a specified file extension.
Iterator for sequentially processing raster cells.
static const int DEFAULT_MAXIMUM_TILE_WIDTH
Default maximum tile width.
static const int DEFAULT_MAXIMUM_TILE_HEIGHT
Default maximum tile height.