move gamma correction code inside brightness/contrast filter

qgis · Jun 30, 2020 · 0214b4f · 0214b4f
1 parent cfa5c5b
commit 0214b4f
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Showing 22 changed files with 68 additions and 493 deletions.
diff --git a/python/core/auto_generated/raster/qgsbrightnesscontrastfilter.sip.in b/python/core/auto_generated/raster/qgsbrightnesscontrastfilter.sip.in
@@ -13,7 +13,7 @@
 class QgsBrightnessContrastFilter : QgsRasterInterface
 {
 %Docstring
-Brightness/contrast filter pipe for rasters.
+Brightness/contrast and gamma correction filter pipe for rasters.
 %End
 
 %TypeHeaderCode
@@ -43,6 +43,9 @@ Brightness/contrast filter pipe for rasters.
     void setContrast( int contrast );
     int contrast() const;
 
+    void setGamma( double gamma );
+    double gamma() const;
+
     virtual void writeXml( QDomDocument &doc, QDomElement &parentElem ) const;
 
 

diff --git a/python/core/auto_generated/raster/qgsgammacorrectionfilter.sip.in b/python/core/auto_generated/raster/qgsgammacorrectionfilter.sip.in
diff --git a/python/core/auto_generated/raster/qgsrasterinterface.sip.in b/python/core/auto_generated/raster/qgsrasterinterface.sip.in
@@ -95,7 +95,6 @@ Base class for processing filters like renderers, reprojector, resampler etc.
 #include "qgsrasterinterface.h"
 // QgsRasterInterface subclasses
 #include <qgsbrightnesscontrastfilter.h>
-#include <qgsgammacorrectionfilter.h>
 #include <qgshuesaturationfilter.h>
 #include <qgsrasterdataprovider.h>
 #include <qgsrasternuller.h>
@@ -116,8 +115,6 @@ Base class for processing filters like renderers, reprojector, resampler etc.
       sipType = sipType_QgsBrightnessContrastFilter;
     else if ( dynamic_cast<QgsHueSaturationFilter *>( sipCpp ) )
       sipType = sipType_QgsHueSaturationFilter;
-    else if ( dynamic_cast<QgsGammaCorrectionFilter *>( sipCpp ) )
-      sipType = sipType_QgsGammaCorrectionFilter;
     else if ( dynamic_cast<QgsRasterDataProvider *>( sipCpp ) )
     {
       sipType = sipType_QgsRasterDataProvider;

diff --git a/python/core/auto_generated/raster/qgsrasterlayer.sip.in b/python/core/auto_generated/raster/qgsrasterlayer.sip.in
@@ -190,8 +190,6 @@ Returns the raster's resample filter.
 
 .. seealso:: :py:func:`brightnessFilter`
 
-.. seealso:: :py:func:`gammaCorrectionFilter`
-
 .. seealso:: :py:func:`hueSaturationFilter`
 %End
 
@@ -201,22 +199,7 @@ Returns the raster's brightness/contrast filter.
 
 .. seealso:: :py:func:`resampleFilter`
 
-.. seealso:: :py:func:`gammaCorrectionFilter`
-
-.. seealso:: :py:func:`hueSaturationFilter`
-%End
-
-    QgsGammaCorrectionFilter *gammaCorrectionFilter() const;
-%Docstring
-Returns the raster's gamma correction filter.
-
-.. seealso:: :py:func:`resampleFilter`
-
-.. seealso:: :py:func:`brightnessFilter`
-
 .. seealso:: :py:func:`hueSaturationFilter`
-
-.. versionadded:: 3.16
 %End
 
     QgsHueSaturationFilter *hueSaturationFilter() const;
@@ -226,8 +209,6 @@ Returns the raster's hue/saturation filter.
 .. seealso:: :py:func:`resampleFilter`
 
 .. seealso:: :py:func:`brightnessFilter`
-
-.. seealso:: :py:func:`gammaCorrectionFilter`
 %End
 
     void setResamplingStage( QgsRasterPipe::ResamplingStage stage );

diff --git a/python/core/auto_generated/raster/qgsrasterpipe.sip.in b/python/core/auto_generated/raster/qgsrasterpipe.sip.in
@@ -31,7 +31,6 @@ Base class for processing modules.
       ProjectorRole,
       NullerRole,
       HueSaturationRole,
-      GammaCorrectionRole
     };
 
     QgsRasterPipe();
@@ -103,13 +102,6 @@ Test if interface at index may be switched on/off
     QgsRasterRenderer *renderer() const;
     QgsRasterResampleFilter *resampleFilter() const;
     QgsBrightnessContrastFilter *brightnessFilter() const;
-
-    QgsGammaCorrectionFilter *gammaCorrectionFilter() const;
-%Docstring
-Returns gamma correction filter pipe
-
-.. versionadded:: 3.16
-%End
     QgsHueSaturationFilter *hueSaturationFilter() const;
     QgsRasterProjector *projector() const;
     QgsRasterNuller *nuller() const;

diff --git a/python/core/core_auto.sip b/python/core/core_auto.sip
@@ -468,7 +468,6 @@
 %Include auto_generated/raster/qgscontrastenhancement.sip
 %Include auto_generated/raster/qgscontrastenhancementfunction.sip
 %Include auto_generated/raster/qgscubicrasterresampler.sip
-%Include auto_generated/raster/qgsgammacorrectionfilter.sip
 %Include auto_generated/raster/qgshillshaderenderer.sip
 %Include auto_generated/raster/qgshuesaturationfilter.sip
 %Include auto_generated/raster/qgslinearminmaxenhancement.sip

diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
@@ -315,7 +315,6 @@ Q_GUI_EXPORT extern int qt_defaultDpiX();
 #include "qgsrasterlayerproperties.h"
 #include "qgsrasternuller.h"
 #include "qgsbrightnesscontrastfilter.h"
-#include "qgsgammacorrectionfilter.h"
 #include "qgsrasterrenderer.h"
 #include "qgsrasterlayersaveasdialog.h"
 #include "qgsrasterprojector.h"
@@ -12257,8 +12256,8 @@ void QgisApp::adjustGamma( double delta )
       return;
     }
 
-    QgsGammaCorrectionFilter *gammaFilter = rasterLayer->gammaCorrectionFilter();
-    gammaFilter->setGamma( gammaFilter->gamma() + delta );
+    QgsBrightnessContrastFilter *brightnessFilter = rasterLayer->brightnessFilter();
+    brightnessFilter->setGamma( brightnessFilter->gamma() + delta );
 
     rasterLayer->triggerRepaint();
   }

diff --git a/src/app/qgisapp.h b/src/app/qgisapp.h
@@ -2120,7 +2120,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     //! Do histogram stretch for singleband gray / multiband color rasters
     void histogramStretch( bool visibleAreaOnly = false, QgsRasterMinMaxOrigin::Limits limits = QgsRasterMinMaxOrigin::MinMax );
 
-    //! Apply raster brightness
+    //! Apply raster brightness/contrast
     void adjustBrightnessContrast( int delta, bool updateBrightness = true );
 
     /**

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
@@ -572,7 +572,6 @@ SET(QGIS_CORE_SRCS
   raster/qgsbilinearrasterresampler.cpp
   raster/qgsbrightnesscontrastfilter.cpp
   raster/qgscubicrasterresampler.cpp
-  raster/qgsgammacorrectionfilter.cpp
   raster/qgshuesaturationfilter.cpp
   raster/qgsmultibandcolorrenderer.cpp
   raster/qgspalettedrasterrenderer.cpp
@@ -1307,7 +1306,6 @@ SET(QGIS_CORE_HDRS
   raster/qgscontrastenhancement.h
   raster/qgscontrastenhancementfunction.h
   raster/qgscubicrasterresampler.h
-  raster/qgsgammacorrectionfilter.h
   raster/qgshillshaderenderer.h
   raster/qgshuesaturationfilter.h
   raster/qgslinearminmaxenhancement.h

diff --git a/src/core/raster/qgsbrightnesscontrastfilter.cpp b/src/core/raster/qgsbrightnesscontrastfilter.cpp
@@ -32,6 +32,7 @@ QgsBrightnessContrastFilter *QgsBrightnessContrastFilter::clone() const
   QgsBrightnessContrastFilter *filter = new QgsBrightnessContrastFilter( nullptr );
   filter->setBrightness( mBrightness );
   filter->setContrast( mContrast );
+  filter->setGamma( mGamma );
   return filter;
 }
 
@@ -122,9 +123,9 @@ QgsRasterBlock *QgsBrightnessContrastFilter::block( int bandNo, QgsRectangle  co
     return outputBlock.release();
   }
 
-  if ( mBrightness == 0 && mContrast == 0 )
+  if ( mBrightness == 0 && mContrast == 0 && mGamma == 1.0 )
   {
-    QgsDebugMsgLevel( QStringLiteral( "No brightness changes." ), 4 );
+    QgsDebugMsgLevel( QStringLiteral( "No brightness/contrast/gamma changes." ), 4 );
     return inputBlock.release();
   }
 
@@ -139,6 +140,7 @@ QgsRasterBlock *QgsBrightnessContrastFilter::block( int bandNo, QgsRectangle  co
 
   int r, g, b, alpha;
   double f = std::pow( ( mContrast + 100 ) / 100.0, 2 );
+  double gammaCorrection = 1.0 / mGamma;
 
   for ( qgssize i = 0; i < ( qgssize )width * height; i++ )
   {
@@ -151,22 +153,22 @@ QgsRasterBlock *QgsBrightnessContrastFilter::block( int bandNo, QgsRectangle  co
     myColor = inputBlock->color( i );
     alpha = qAlpha( myColor );
 
-    r = adjustColorComponent( qRed( myColor ), alpha, mBrightness, f );
-    g = adjustColorComponent( qGreen( myColor ), alpha, mBrightness, f );
-    b = adjustColorComponent( qBlue( myColor ), alpha, mBrightness, f );
+    r = adjustColorComponent( qRed( myColor ), alpha, mBrightness, f, gammaCorrection );
+    g = adjustColorComponent( qGreen( myColor ), alpha, mBrightness, f, gammaCorrection );
+    b = adjustColorComponent( qBlue( myColor ), alpha, mBrightness, f, gammaCorrection );
 
     outputBlock->setColor( i, qRgba( r, g, b, alpha ) );
   }
 
   return outputBlock.release();
 }
 
-int QgsBrightnessContrastFilter::adjustColorComponent( int colorComponent, int alpha, int brightness, double contrastFactor ) const
+int QgsBrightnessContrastFilter::adjustColorComponent( int colorComponent, int alpha, int brightness, double contrastFactor, double gammaCorrection ) const
 {
   if ( alpha == 255 )
   {
     // Opaque pixel, do simpler math
-    return qBound( 0, ( int )( ( ( ( ( ( colorComponent / 255.0 ) - 0.5 ) * contrastFactor ) + 0.5 ) * 255 ) + brightness ), 255 );
+    return qBound( 0, ( int )( 255 * std::pow( ( ( ( ( ( ( colorComponent / 255.0 ) - 0.5 ) * contrastFactor ) + 0.5 ) * 255 ) + brightness ) / 255.0, gammaCorrection ) ), 255 );
   }
   else if ( alpha == 0 )
   {
@@ -181,7 +183,7 @@ int QgsBrightnessContrastFilter::adjustColorComponent( int colorComponent, int a
     double adjustedColor = colorComponent / alphaFactor;
 
     // Make sure to return a premultiplied color
-    return alphaFactor * qBound( 0., ( ( ( ( ( ( adjustedColor / 255.0 ) - 0.5 ) * contrastFactor ) + 0.5 ) * 255 ) + brightness ), 255. );
+    return alphaFactor * qBound( 0., std::pow( ( ( ( ( ( ( adjustedColor / 255.0 ) - 0.5 ) * contrastFactor ) + 0.5 ) * 255 ) + brightness ) / 255, gammaCorrection ), 255. );
   }
 }
 
@@ -196,6 +198,7 @@ void QgsBrightnessContrastFilter::writeXml( QDomDocument &doc, QDomElement &pare
 
   filterElem.setAttribute( QStringLiteral( "brightness" ), QString::number( mBrightness ) );
   filterElem.setAttribute( QStringLiteral( "contrast" ), QString::number( mContrast ) );
+  filterElem.setAttribute( QStringLiteral( "gamma" ), QString::number( mGamma ) );
   parentElem.appendChild( filterElem );
 }
 
@@ -208,4 +211,5 @@ void QgsBrightnessContrastFilter::readXml( const QDomElement &filterElem )
 
   mBrightness = filterElem.attribute( QStringLiteral( "brightness" ), QStringLiteral( "0" ) ).toInt();
   mContrast = filterElem.attribute( QStringLiteral( "contrast" ), QStringLiteral( "0" ) ).toInt();
+  mGamma = filterElem.attribute( QStringLiteral( "gamma" ), QStringLiteral( "1" ) ).toDouble();
 }
diff --git a/src/core/raster/qgsbrightnesscontrastfilter.h b/src/core/raster/qgsbrightnesscontrastfilter.h
@@ -26,7 +26,7 @@ class QDomElement;
 
 /**
  * \ingroup core
-  * Brightness/contrast filter pipe for rasters.
+  * Brightness/contrast and gamma correction filter pipe for rasters.
   */
 class CORE_EXPORT QgsBrightnessContrastFilter : public QgsRasterInterface
 {
@@ -49,20 +49,27 @@ class CORE_EXPORT QgsBrightnessContrastFilter : public QgsRasterInterface
     void setContrast( int contrast ) { mContrast = qBound( -100, contrast, 100 ); }
     int contrast() const { return mContrast; }
 
+    void setGamma( double gamma ) { mGamma = qBound( 0.1, gamma, 10.0 ); }
+    double gamma() const { return mGamma; }
+
     void writeXml( QDomDocument &doc, QDomElement &parentElem ) const override;
 
     //! Sets base class members from xml. Usually called from create() methods of subclasses
     void readXml( const QDomElement &filterElem ) override;
 
   private:
-    //! Adjusts a color component by the specified brightness and contrast factor
-    int  adjustColorComponent( int colorComponent, int alpha, int brightness, double contrastFactor ) const;
+    //! Adjusts a color component by the specified brightness, contrast factor and gamma correction
+    int  adjustColorComponent( int colorComponent, int alpha, int brightness, double contrastFactor, double gammaCorrection ) const;
 
     //! Current brightness coefficient value. Default: 0. Range: -255...255
     int mBrightness = 0;
 
     //! Current contrast coefficient value. Default: 0. Range: -100...100
-    double mContrast = 0;
+    int mContrast = 0;
+
+    //! Current gamma value. Default: 1. Range: 0.1…10.0
+    double mGamma = 1.0;
+
 };
 
 #endif // QGSBRIGHTNESSCONTRASTFILTER_H