HistogramEditor Class Reference

Interface for adjusting image historgram using upper and lower bounds and bright and contrast controls. More...

#include <histogramEditor.h>

Inheritance diagram for HistogramEditor:

Collaboration diagram for HistogramEditor:

Public Member Functions
	HistogramEditor (QString filename, QWidget *parent=0, const char *name=0)
	Constructs layout.
	~HistogramEditor ()
QImage *	getModifiedImage ()
	get modified image that resulted from adjustments
void	getHistBoundaries (int &lumLeft, int &lumRight, int &redLeft, int &redRight, int &greenLeft, int &greenRight, int &blueLeft, int &blueRight)
	returns histogram boundaries

Protected Member Functions
void	keyPressEvent (QKeyEvent *e)
void	keyReleaseEvent (QKeyEvent *e)

Private Slots
void	selectPreviewImageType (int selection)
	updates preview image
void	selectHistogramType (int selection)
	updates historgram interface
void	resetBrightness ()
	reset brightness
void	resetContrast ()
	reset contrast
void	applyAction ()
	check for changes to settings, if so
void	resetAction ()
	resets all adjustments
void	generateAdjustedPreviewImage ()
	updates adjusted preview image

Private Member Functions
void	adjustImage (QImage &image)
double	scaleColor (double color, int left, int right)

Private Attributes
QString	fileName
double	meanR
	Mean color values.
double	meanG
double	meanB
ScaledPreviewInterface *	previewInterface
	Preview image.
HistogramInterface *	histogramInterface
	Histogram view.
QComboBox *	previewSelection
QComboBox *	histogramType
ClickableLabel *	brightnessIcon
ClickableLabel *	contrastIcon
Q3Frame *	buttonsFrame
DynamicSlider *	brightness
	Brightness slider.
DynamicSlider *	contrast
	Contrast slider.

Detailed Description

Interface for adjusting image historgram using upper and lower bounds and bright and contrast controls.

Definition at line 34 of file histogramEditor.h.

Constructor & Destructor Documentation

HistogramEditor()

HistogramEditor::HistogramEditor	(	QString	filename,
		QWidget *	parent = 0,
		const char *	name = 0 )

Constructs layout.

Definition at line 40 of file histogramEditor.cpp.

                                                                                      : QDialog(parent,name,true)
{
  //set pointer to null to make sure no 
  //random data is ever accessed by the preview interface
  histogramInterface = NULL;
 
  //record filename
  this->fileName = fileName;
  
  //-----
  //find mean color values
  meanR = 0;
  meanG = 0;
  meanB = 0;
  int x, y;
  QRgb* rgb;
  uchar* scanLine;
  QImage image = QImage( fileName );
  for( y=0; y<image.height(); y++)
  {   
    scanLine = image.scanLine(y);
    for( x=0; x<image.width(); x++)
    {
      rgb = ((QRgb*)scanLine+x);
      double r = ((double)qRed(*rgb)   )/255.0;
      double g = ((double)qGreen(*rgb) )/255.0;
      double b = ((double)qBlue(*rgb)  )/255.0;
      
      meanR+=r;
      meanG+=g;
      meanB+=b;
    } //x
  } //y
  meanR = meanR / ( image.width() * image.height() );
  meanG = meanG / ( image.width() * image.height() );
  meanB = meanB / ( image.width() * image.height() );
  
  Q3Frame* visibleFrame = new Q3Frame( this, "visible widgets" );
  //--------------  
  //Preview frame: 
  previewInterface = new ScaledPreviewInterface( fileName, visibleFrame, 
                                                 "previewInterface" );
  connect( previewInterface, SIGNAL(resized()), 
           this, SLOT(generateAdjustedPreviewImage()) );  
 
  previewSelection = new QComboBox( visibleFrame, "previewSelction" );
  previewSelection->insertItem( tr("Split View") );
  previewSelection->insertItem( tr("Original Image") );
  previewSelection->insertItem( tr("Adjusted Image") );
  connect( previewSelection, SIGNAL(activated(int)), this, SLOT(selectPreviewImageType(int)) );  
  //--------------
  //Adjust frame:   
  histogramInterface = new HistogramInterface( fileName, visibleFrame, 
                                               "histogramInterface" );  
 
  //connect adjustments in histogram to generateAdjustedPreviewImage
  connect( histogramInterface, SIGNAL( selectedRangeChanged() ),
           SLOT( generateAdjustedPreviewImage() ) );
  
  QToolTip::add( histogramInterface, tr("Click and drag to select tonal range") );  
 
  histogramType = new QComboBox( visibleFrame, "histogramType" );
  histogramType->insertItem( tr("Luminosity") );
  histogramType->insertItem( tr("Red") );
  histogramType->insertItem( tr("Green") );
  histogramType->insertItem( tr("Blue") );  
  connect( histogramType, SIGNAL(activated(int)), this, SLOT(selectHistogramType(int)) );  
  QToolTip::add( histogramType, tr("Histogram channel displayed") );  
  //--------------
  //Slider frame:
  QString noChange = QString( tr("No change") );
  
  brightness = new DynamicSlider( Qt::Vertical, visibleFrame );
  brightness->setZeroString( noChange );
  brightness->setPrefixes("", "+");
  brightness->setMinValue( -SLIDER_RADIUS );
  brightness->setMaxValue( SLIDER_RADIUS );
  connect( brightness, SIGNAL(valueChanged(int)),
           this, SLOT(generateAdjustedPreviewImage()) );;
  QToolTip::add( brightness, tr("Drag to adjust image brightness") );  
           
  brightnessIcon = new ClickableLabel( visibleFrame, "brightnessIcon" );
  brightnessIcon->setPixmap( QPixmap(QString(IMAGE_PATH)+"miscImages/brightness.png") );
  connect( brightnessIcon, SIGNAL(clicked()), SLOT(resetBrightness()) );    
  QToolTip::add( brightnessIcon, tr("Reset brightness") );
 
  contrast = new DynamicSlider( Qt::Vertical, visibleFrame );
  contrast->setZeroString( noChange );
  contrast->setPrefixes("", "+");
  contrast->setMinValue( -SLIDER_RADIUS );
  contrast->setMaxValue( SLIDER_RADIUS );
  connect( contrast, SIGNAL(valueChanged(int)),
           this, SLOT(generateAdjustedPreviewImage()) );
  QToolTip::add( contrast, tr("Drag to adjust image contrast") );  
 
  contrastIcon = new ClickableLabel( visibleFrame, "contrastIcon" );
  contrastIcon->setPixmap( QPixmap(QString(IMAGE_PATH)+"miscImages/contrast.png") );
  connect( contrastIcon, SIGNAL(clicked()), SLOT(resetContrast()) );    
  QToolTip::add( contrastIcon, tr("Reset contrast") );
  //--------------
  //Dialog buttons:  
  buttonsFrame =   new Q3Frame( visibleFrame, "dialogButtons" );
 
  QPushButton* applyButton = new QPushButton( tr("Apply"), buttonsFrame );
  applyButton->setDefault(true);
  applyButton->setFocus();
  connect( applyButton, SIGNAL(clicked()), SLOT(applyAction()) );
                                
  QPushButton* cancelButton = new QPushButton( tr("Cancel"), buttonsFrame );
  connect( cancelButton, SIGNAL(clicked()), SLOT(reject()) );
 
  QPushButton* resetButton = new QPushButton( tr("Reset"), buttonsFrame );
  connect( resetButton, SIGNAL(clicked()), SLOT(resetAction()) );
 
  Q3GridLayout* buttonsGrid = new Q3GridLayout( buttonsFrame, 1, 5, 0 );
  buttonsGrid->setColStretch( 0, 1 );
  buttonsGrid->addWidget( applyButton,  0, 1 );
  buttonsGrid->addWidget( cancelButton, 0, 2 );
  buttonsGrid->addWidget( resetButton, 0, 3 );
  buttonsGrid->setColStretch( 4, 1 );  
  buttonsGrid->setSpacing( WIDGET_SPACING );
  //--------------
  Q3GridLayout* mainGrid = new Q3GridLayout( visibleFrame, 5, 3, 0 );
  
  mainGrid->addMultiCellWidget( previewInterface,     0,0, 0,2 );
  mainGrid->addMultiCellWidget( previewSelection, 1,1, 0,2, Qt::AlignHCenter );  
   
  mainGrid->addWidget( histogramInterface,    2, 0 ); 
  mainGrid->addWidget( brightness,            2, 1 );
  mainGrid->addWidget( contrast,              2, 2 );
  
  //make sure sliders have enough space so all slider units are settable
  mainGrid->setRowSpacing( 2, 2*SLIDER_RADIUS + 5) ;
    
  mainGrid->addWidget( histogramType,    3, 0, Qt::AlignHCenter );
  mainGrid->addWidget( brightnessIcon,   3, 1 );  
  mainGrid->addWidget( contrastIcon,     3, 2 );  
  
  mainGrid->addMultiCellWidget( buttonsFrame, 4,4, 0,2 );
 
  mainGrid->setRowStretch( 0, 1 );
  mainGrid->setColStretch( 0, 1 );
  
  mainGrid->setSpacing( WIDGET_SPACING );
  mainGrid->setMargin( WIDGET_SPACING );
  
  Q3GridLayout* invisibleGrid = new Q3GridLayout( this, 2, 1, 0 );
  invisibleGrid->addWidget( visibleFrame, 0, 0 );
  invisibleGrid->setRowStretch( 0, 1 );
  
  //PLATFORM_SPECIFIC_CODE
  //windows users expect a grip, but qt doesn't put one in by default. we'll add
  //it for them too. :-)
#if defined(Q_OS_WIN)
  QSizeGrip* sizeGrip = new QSizeGrip( this );
  invisibleGrid->addWidget( sizeGrip, 1, 0, Qt::AlignRight | Qt::AlignBottom );
#endif
  
  
  
  
  //Window caption
  setCaption( tr("Histogram Editor") );
  //-------------------------------
}

References applyAction(), b, brightness, brightnessIcon, buttonsFrame, contrast, contrastIcon, fileName, generateAdjustedPreviewImage(), histogramInterface, histogramType, IMAGE_PATH, meanB, meanG, meanR, previewInterface, previewSelection, resetAction(), resetBrightness(), resetContrast(), selectHistogramType(), selectPreviewImageType(), ClickableLabel::setPixmap(), DynamicSlider::setPrefixes(), DynamicSlider::setZeroString(), SLIDER_RADIUS, and WIDGET_SPACING.

~HistogramEditor()

HistogramEditor::~HistogramEditor

(

)

Definition at line 206 of file histogramEditor.cpp.

{ }

Member Function Documentation

adjustImage()

void HistogramEditor::adjustImage ( QImage & image )

private

Definition at line 302 of file histogramEditor.cpp.

{
  //obtain histogram left and right boundaries
  //sanity check
  int lumLeft, lumRight, redLeft, redRight, greenLeft, greenRight, blueLeft, blueRight;
  if( histogramInterface )
  {
    histogramInterface->getHistBoundaries( lumLeft, lumRight,
                                           redLeft, redRight,
                                           greenLeft, greenRight,
                                           blueLeft, blueRight );
  }
  else
  {
    lumLeft = 0; lumRight = 255;
    redLeft = 0; redRight = 255;
    greenLeft = 0; greenRight = 255;
    blueLeft = 0; blueRight = 255;
  }
  
  //modify image
  double displayToOneScalar = 1.0/255.0;
  double scaledMeanR = displayToOneScalar*scaleColor( 255.0*meanR, redLeft, redRight );
  double scaledMeanG = displayToOneScalar*scaleColor( 255.0*meanG, greenLeft, greenRight );
  double scaledMeanB = displayToOneScalar*scaleColor( 255.0*meanB, blueLeft, blueRight );
  
  double brightnessScalar, addedBrightnessColor;
  if(brightness->value() < 0)
  {
    brightnessScalar = ((double)(SLIDER_RADIUS + brightness->value()))/SLIDER_RADIUS;
    addedBrightnessColor = 1.0 - brightnessScalar;
  }
  else
  {
    brightnessScalar = ((double)(SLIDER_RADIUS - brightness->value()))/SLIDER_RADIUS;
    addedBrightnessColor = 0.0;
  }
  
  int x, y;  
  QRgb* rgb;
  double r,g,b;
  double h,s,v;
  int rPrime, gPrime, bPrime;
  uchar* scanLine;
  
  for( y=0; y<image.height(); y++)
  {   
    scanLine = image.scanLine(y);
    for( x=0; x<image.width(); x++)
    {
      //get rgb value
      rgb = ((QRgb*)scanLine+x);
      r = qRed(*rgb);
      g = qGreen(*rgb);
      b = qBlue(*rgb);
      
      //apply histogram boundaries
      RGBtoHSV(r,g,b,&h,&s,&v);
      v = scaleColor( v, lumLeft, lumRight );
      HSVtoRGB( &r,&g,&b, h,s,v);         
      
      r = scaleColor( r, redLeft, redRight );
      g = scaleColor( g, greenLeft, greenRight );
      b = scaleColor( b, blueLeft, blueRight );
      
      //convert to 0-1 scale
      r = r*displayToOneScalar;
      g = g*displayToOneScalar;
      b = b*displayToOneScalar;
      
      //adjust contrast
      r = ( (r-scaledMeanR) * (SLIDER_RADIUS-contrast->value()) )/SLIDER_RADIUS + scaledMeanR;
      g = ( (g-scaledMeanG) * (SLIDER_RADIUS-contrast->value()) )/SLIDER_RADIUS + scaledMeanG;
      b = ( (b-scaledMeanB) * (SLIDER_RADIUS-contrast->value()) )/SLIDER_RADIUS + scaledMeanB;
      
      //apply brightness adjustment
      //http://www.sgi.com/misc/grafica/interp/
      r = brightnessScalar*r + addedBrightnessColor;
      g = brightnessScalar*g + addedBrightnessColor;
      b = brightnessScalar*b + addedBrightnessColor;
      
      //scale and clamp to 0-255 range
      rPrime = (int) MIN( MAX((r*255), 0), 255 );
      gPrime = (int) MIN( MAX((g*255), 0), 255 );
      bPrime = (int) MIN( MAX((b*255), 0), 255 );
      
      //set adjusted color value
      *rgb = qRgb(rPrime, gPrime, bPrime);          
    } //x
  } //y  
}

References b, brightness, contrast, HistogramInterface::getHistBoundaries(), histogramInterface, HSVtoRGB(), MAX, meanB, meanG, meanR, MIN, RGBtoHSV(), scaleColor(), and SLIDER_RADIUS.

Referenced by generateAdjustedPreviewImage(), and getModifiedImage().

applyAction

void HistogramEditor::applyAction ( )

privateslot

check for changes to settings, if so

Definition at line 208 of file histogramEditor.cpp.

{
  //check if user has adjusted brightness, contrast, or histogram ranges.
  //if any changes have taken place call "accept", else "reject" so image is not
  //updated and appear modified
  int lumLeft, lumRight, redLeft, redRight, greenLeft, greenRight, blueLeft, blueRight;
  histogramInterface->getHistBoundaries( lumLeft, lumRight,
                                         redLeft, redRight,
                                         greenLeft, greenRight,
                                         blueLeft, blueRight );  
  if( brightness->value() != 0 || contrast->value()   != 0 ||
      lumLeft != 0 || lumRight != 255 ||
      redLeft !=0 || redRight != 255 ||
      greenLeft != 0 || greenRight != 255 ||
      blueLeft != 0 || blueRight != 255 )
  { accept(); }
  else
  { reject(); }  
}

References brightness, contrast, HistogramInterface::getHistBoundaries(), and histogramInterface.

Referenced by HistogramEditor().

generateAdjustedPreviewImage

void HistogramEditor::generateAdjustedPreviewImage ( )

privateslot

updates adjusted preview image

Definition at line 289 of file histogramEditor.cpp.

{
  //get original image
  QImage origImage = previewInterface->getOrigImage();
 
  //construct adjusted image
  QImage adjustedImage = origImage.copy();
  adjustImage( adjustedImage );
  
  //set adjusted image
  previewInterface->setAdjustedImage( adjustedImage );
}

References adjustImage(), SplitViewInterface::getOrigImage(), previewInterface, and SplitViewInterface::setAdjustedImage().

Referenced by HistogramEditor().

getHistBoundaries()

void HistogramEditor::getHistBoundaries	(	int &	lumLeft,
		int &	lumRight,
		int &	redLeft,
		int &	redRight,
		int &	greenLeft,
		int &	greenRight,
		int &	blueLeft,
		int &	blueRight )

returns histogram boundaries

Definition at line 267 of file histogramEditor.cpp.

{
  //sanity check
  if( histogramInterface )
  {
    histogramInterface->getHistBoundaries( lumLeft, lumRight,
                                           redLeft, redRight,
                                           greenLeft, greenRight,
                                           blueLeft, blueRight );
  }
  else
  {
    lumLeft = 0; lumRight = 255;
    redLeft = 0; redRight = 255;
    greenLeft = 0; greenRight = 255;
    blueLeft = 0; blueRight = 255;
  }
}

References HistogramInterface::getHistBoundaries(), and histogramInterface.

getModifiedImage()

QImage * HistogramEditor::getModifiedImage

(

)

get modified image that resulted from adjustments

Definition at line 235 of file histogramEditor.cpp.

{ 
  QImage* adjustedImage = new QImage(fileName);
  
  //convert to 32-bit depth if necessary
  if( adjustedImage->depth() < 32 )
  {
    QImage* tmp = adjustedImage;
    adjustedImage = new QImage( tmp->convertDepth( 32, Qt::AutoColor ) );
    delete tmp; tmp=NULL;
  }
  
  adjustImage( *adjustedImage );
  return adjustedImage;  
}

References adjustImage(), and fileName.

Referenced by EditingInterface::tuneLevels().

keyPressEvent()

void HistogramEditor::keyPressEvent ( QKeyEvent * e )

protected

Definition at line 399 of file histogramEditor.cpp.

{
  if(e->key() == Qt::Key_Control )
  {
    PREVIEW_MODE curMode = (PREVIEW_MODE) previewSelection->currentItem();
    if(curMode == ORIGINAL_IMAGE)
      previewInterface->setPreviewMode( ADJUSTED_IMAGE, true );
    else if(curMode == ADJUSTED_IMAGE)
      previewInterface->setPreviewMode( ORIGINAL_IMAGE, true );
    else
      previewInterface->setPreviewMode( INV_SPLIT_VIEW );
  }
  else { QDialog::keyPressEvent(e); }
}

References ADJUSTED_IMAGE, INV_SPLIT_VIEW, ORIGINAL_IMAGE, previewInterface, previewSelection, and SplitViewInterface::setPreviewMode().

keyReleaseEvent()

void HistogramEditor::keyReleaseEvent ( QKeyEvent * e )

protected

Definition at line 414 of file histogramEditor.cpp.

{
  if(e->key() == Qt::Key_Control )
  {
    previewInterface->setPreviewMode( (PREVIEW_MODE) previewSelection->currentItem(), 
                                      false );
  }
  else { QDialog::keyReleaseEvent(e); }
}

References previewInterface, previewSelection, and SplitViewInterface::setPreviewMode().

resetAction

void HistogramEditor::resetAction ( )

privateslot

resets all adjustments

Definition at line 228 of file histogramEditor.cpp.

{
  histogramInterface->resetBoundaries();
  resetBrightness();
  resetContrast();
}

References histogramInterface, HistogramInterface::resetBoundaries(), resetBrightness(), and resetContrast().

Referenced by HistogramEditor().

resetBrightness

void HistogramEditor::resetBrightness ( )

privateslot

reset brightness

Definition at line 261 of file histogramEditor.cpp.

{ brightness->setValue( 0 ); }

References brightness.

Referenced by HistogramEditor(), and resetAction().

resetContrast

void HistogramEditor::resetContrast ( )

privateslot

reset contrast

Definition at line 264 of file histogramEditor.cpp.

{ contrast->setValue( 0 ); }

References contrast.

Referenced by HistogramEditor(), and resetAction().

scaleColor()

double HistogramEditor::scaleColor ( double color, int left, int right )

private

Definition at line 394 of file histogramEditor.cpp.

{
  return MAX( MIN( (255.0*(color-left)) / (right-left), 255), 0 );  
}

References MAX, and MIN.

Referenced by adjustImage().

selectHistogramType

void HistogramEditor::selectHistogramType ( int selection )

privateslot

updates historgram interface

Definition at line 256 of file histogramEditor.cpp.

{
  histogramInterface->setDisplayChannel( (DISPLAYED_CHANNEL) selection );
}

References histogramInterface, and HistogramInterface::setDisplayChannel().

Referenced by HistogramEditor().

selectPreviewImageType

void HistogramEditor::selectPreviewImageType ( int selection )

privateslot

updates preview image

Definition at line 251 of file histogramEditor.cpp.

{
  previewInterface->setPreviewMode( (PREVIEW_MODE)selection );
}

References previewInterface, and SplitViewInterface::setPreviewMode().

Referenced by HistogramEditor().

Member Data Documentation

brightness

DynamicSlider* HistogramEditor::brightness

private

Brightness slider.

Definition at line 108 of file histogramEditor.h.

Referenced by adjustImage(), applyAction(), HistogramEditor(), and resetBrightness().

brightnessIcon

ClickableLabel* HistogramEditor::brightnessIcon

private

Definition at line 102 of file histogramEditor.h.

Referenced by HistogramEditor().

buttonsFrame

Q3Frame* HistogramEditor::buttonsFrame

private

Definition at line 104 of file histogramEditor.h.

Referenced by HistogramEditor().

contrast

DynamicSlider* HistogramEditor::contrast

private

Contrast slider.

Definition at line 111 of file histogramEditor.h.

Referenced by adjustImage(), applyAction(), HistogramEditor(), and resetContrast().

contrastIcon

ClickableLabel* HistogramEditor::contrastIcon

private

Definition at line 103 of file histogramEditor.h.

Referenced by HistogramEditor().

fileName

QString HistogramEditor::fileName

private

Definition at line 89 of file histogramEditor.h.

Referenced by getModifiedImage(), and HistogramEditor().

histogramInterface

HistogramInterface* HistogramEditor::histogramInterface

private

Histogram view.

Definition at line 98 of file histogramEditor.h.

Referenced by adjustImage(), applyAction(), getHistBoundaries(), HistogramEditor(), resetAction(), and selectHistogramType().

histogramType

QComboBox* HistogramEditor::histogramType

private

Definition at line 101 of file histogramEditor.h.

Referenced by HistogramEditor().

meanB

double HistogramEditor::meanB

private

Definition at line 92 of file histogramEditor.h.

Referenced by adjustImage(), and HistogramEditor().

meanG

double HistogramEditor::meanG

private

Definition at line 92 of file histogramEditor.h.

Referenced by adjustImage(), and HistogramEditor().

meanR

double HistogramEditor::meanR

private

Mean color values.

Definition at line 92 of file histogramEditor.h.

Referenced by adjustImage(), and HistogramEditor().

previewInterface

ScaledPreviewInterface* HistogramEditor::previewInterface

private

Preview image.

Definition at line 95 of file histogramEditor.h.

Referenced by generateAdjustedPreviewImage(), HistogramEditor(), keyPressEvent(), keyReleaseEvent(), and selectPreviewImageType().

previewSelection

QComboBox* HistogramEditor::previewSelection

private

Definition at line 100 of file histogramEditor.h.

Referenced by HistogramEditor(), keyPressEvent(), and keyReleaseEvent().

---

The documentation for this class was generated from the following files:

• histogramEditor.h
• histogramEditor.cpp