QGIS API Documentation
qgslinearminmaxenhancementwithclip.cpp
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1 /* **************************************************************************
2  qgslinearminmaxenhancementwithclip.cpp - description
3  -------------------
4 begin : Fri Nov 16 2007
5 copyright : (C) 2007 by Peter J. Ersts
6 email : [email protected]
7 
8 ****************************************************************************/
9 
10 /* **************************************************************************
11  * *
12  * This program is free software; you can redistribute it and/or modify *
13  * it under the terms of the GNU General Public License as published by *
14  * the Free Software Foundation; either version 2 of the License, or *
15  * (at your option) any later version. *
16  * *
17  ***************************************************************************/
18 
20 
21 QgsLinearMinMaxEnhancementWithClip::QgsLinearMinMaxEnhancementWithClip( QGis::DataType theQgsRasterDataType, double theMinimumValue, double theMaximumValue ) : QgsContrastEnhancementFunction( theQgsRasterDataType, theMinimumValue, theMaximumValue )
22 {
23 }
24 
26 {
27  if ( theValue < mMinimumValue || theValue > mMaximumValue )
28  {
29  return -1;
30  }
31 
32  int myStretchedValue = static_cast<int>((( theValue - mMinimumValue ) / ( mMinimumMaximumRange ) ) * 255.0 );
33  if ( myStretchedValue < 0 )
34  {
35  return 0;
36  }
37  else if ( myStretchedValue > 255 )
38  {
39  return 255;
40  }
41 
42  return myStretchedValue;
43 }
44 
46 {
47  if ( theValue < mMinimumValue || theValue > mMaximumValue )
48  {
49  return false;
50  }
51 
52  return true;
53 }
double mMinimumMaximumRange
Minimum maximum range for the band, used for enhanceContrasting.
bool isValueInDisplayableRange(double) override
A customicable method to indicate if the pixels is displayable.
A contrast enhancement funcion is the base class for all raster contrast enhancements.
double mMaximumValue
User defineable maximum value for the band, used for enhanceContrasting.
double mMinimumValue
User defineable minimum value for the band, used for enhanceContrasting.
QgsLinearMinMaxEnhancementWithClip(QGis::DataType, double, double)
DataType
Raster data types.
Definition: qgis.h:129
int enhance(double) override
A customizable method that takes in a double and returns a int between 0 and 255. ...