1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
class QgsAlignRaster
{
%TypeHeaderCode
#include <qgsalignraster.h>
%End
public:
QgsAlignRaster();
//! Utility class for gathering information about rasters
struct RasterInfo
{
public:
//! Construct raster info with a path to a raster file
RasterInfo( const QString& layerpath );
~RasterInfo();
//! Check whether the given path is a valid raster
bool isValid() const;
//! Return CRS in WKT format
QString crs() const;
//! Return size of the raster grid in pixels
QSize rasterSize() const;
//! Return number of raster bands in the file
int bandCount() const;
//! Return cell size in map units
QSizeF cellSize() const;
//! Return grid offset
QPointF gridOffset() const;
//! Return extent of the raster
QgsRectangle extent() const;
//! Return origin of the raster
QPointF origin() const;
//! write contents of the object to standard error stream - for debugging
void dump() const;
//! Get raster value at the given coordinates (from the first band)
double identify( double mx, double my );
private:
RasterInfo( const QgsAlignRaster::RasterInfo& rh );
};
//! Resampling algorithm to be used (equivalent to GDAL's enum GDALResampleAlg)
enum ResampleAlg
{
RA_NearestNeighbour = 0, //!< Nearest neighbour (select on one input pixel)
RA_Bilinear = 1, //!< Bilinear (2x2 kernel)
RA_Cubic = 2, //!< Cubic Convolution Approximation (4x4 kernel)
RA_CubicSpline = 3, //!< Cubic B-Spline Approximation (4x4 kernel)
RA_Lanczos = 4, //!< Lanczos windowed sinc interpolation (6x6 kernel)
RA_Average = 5, //!< Average (computes the average of all non-NODATA contributing pixels)
RA_Mode = 6 //!< Mode (selects the value which appears most often of all the sampled points)
};
//! Definition of one raster layer for alignment
struct Item
{
Item( const QString& input, const QString& output );
//! filename of the source raster
QString inputFilename;
//! filename of the newly created aligned raster (will be overwritten if exists already)
QString outputFilename;
//! resampling method to be used
QgsAlignRaster::ResampleAlg resampleMethod;
//! rescaling of values according to the change of pixel size
bool rescaleValues;
// private part
//! used for rescaling of values (if necessary)
double srcCellSizeInDestCRS;
};
typedef QList<QgsAlignRaster::Item> List;
//! Helper struct to be sub-classed for progress reporting
struct ProgressHandler
{
//! Method to be overridden for progress reporting.
//! @param complete Overall progress of the alignment operation
//! @return false if the execution should be cancelled, true otherwise
virtual bool progress( double complete ) = 0;
virtual ~ProgressHandler();
};
//! Assign a progress handler instance. Does not take ownership. NULL can be passed.
void setProgressHandler( ProgressHandler* progressHandler );
//! Get associated progress handler. May be NULL (default)
ProgressHandler* progressHandler() const;
//! Set list of rasters that will be aligned
void setRasters( const List& list );
//! Get list of rasters that will be aligned
List rasters() const;
void setGridOffset( QPointF offset );
QPointF gridOffset() const;
//! Set output cell size
void setCellSize( double x, double y );
//! Set output cell size
void setCellSize( QSizeF size );
//! Get output cell size
QSizeF cellSize() const;
//! Set the output CRS in WKT format
void setDestinationCRS( const QString& crsWkt );
//! Get the output CRS in WKT format
QString destinationCRS() const;
//! Configure clipping extent (region of interest).
//! No extra clipping is done if the rectangle is null
void setClipExtent( double xmin, double ymin, double xmax, double ymax );
//! Configure clipping extent (region of interest).
//! No extra clipping is done if the rectangle is null
void setClipExtent( const QgsRectangle& extent );
//! Get clipping extent (region of interest).
//! No extra clipping is done if the rectangle is null
QgsRectangle clipExtent() const;
//! Set destination CRS, cell size and grid offset from a raster file.
//! The user may provide custom values for some of the parameters - in such case
//! only the remaining parameters are calculated.
//!
//! If default CRS is used, the parameters are set according to the raster file's geo-transform.
//! If a custom CRS is provided, suggested reprojection is calculated first (using GDAL) in order
//! to determine suitable defaults for cell size and grid offset.
//!
//! @return true on success (may fail if it is not possible to reproject raster to given CRS)
bool setParametersFromRaster( const QgsAlignRaster::RasterInfo& rasterInfo, const QString& customCRSWkt = QString(), QSizeF customCellSize = QSizeF(), QPointF customGridOffset = QPointF( -1, -1 ) );
//! Overridden variant for convenience, taking filename instead RasterInfo object.
//! See the other variant for details.
bool setParametersFromRaster( const QString& filename, const QString& customCRSWkt = QString(), QSizeF customCellSize = QSizeF(), QPointF customGridOffset = QPointF( -1, -1 ) );
//! Determine destination extent from the input rasters and calculate derived values
//! @return true on success, sets error on error (see errorMessage())
bool checkInputParameters();
//! Return expected size of the resulting aligned raster
//! @note first need to run checkInputParameters() which returns with success
QSize alignedRasterSize() const;
//! Return expected extent of the resulting aligned raster
//! @note first need to run checkInputParameters() which returns with success
QgsRectangle alignedRasterExtent() const;
//! Run the alignment process
//! @return true on success, sets error on error (see errorMessage())
bool run();
//! Return error from a previous run() call.
//! Error message is empty if run() succeeded (returned true)
QString errorMessage() const;
//! write contents of the object to standard error stream - for debugging
void dump() const;
//! Return index of the layer which has smallest cell size (returns -1 on error)
int suggestedReferenceLayer() const;
protected:
//! Internal function for processing of one raster (1. create output, 2. do the alignment)
bool createAndWarp( const Item& raster );
//! Determine suggested output of raster warp to a different CRS. Returns true on success
static bool suggestedWarpOutput( const RasterInfo& info, const QString& destWkt, QSizeF* cellSize = 0, QPointF* gridOffset = 0, QgsRectangle* rect = 0 );
};
|
