color.h File Reference

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions
QImage *	improveColorBalance (QString filename, StatusWidget *status)

---

Function Documentation

QImage* improveColorBalance (  QString  filename, StatusWidget *  status )

Definition at line 89 of file color.cpp. References b, editedImage, StatusWidget::incrementProgress(), newProgress, StatusWidget::setStatus(), StatusWidget::showProgressBar(), status, and updateIncrement. Referenced by EditingInterface::colorBalance(). { //load original image QImage* editedImage = new QImage( filename ); //convert to 32-bit depth if necessary if( editedImage->depth() < 32 ) { QImage* tmp = editedImage; editedImage = new QImage( tmp->convertDepth( 32, Qt::AutoColor ) ); delete tmp; tmp=NULL; } //setup progress bar QString statusMessage = qApp->translate( "improveColorBalance", "Enhancing Color Balance:" ); status->showProgressBar( statusMessage, 100 ); qApp->processEvents(); //update progress bar for every 1% of completion const int updateIncrement = (int) ( 0.01 * editedImage->width() * editedImage->height() ); int newProgress = 0; //construct intensity histographs for each color channel int redVals[256]; int greenVals[256]; int blueVals[256]; int i=0; for(i=0; i<256; i++) { redVals[i] = 0; greenVals[i] = 0; blueVals[i] = 0; } //populate histogram by iterating over all image pixels int numPixels = editedImage->width()*editedImage->height(); QRgb* rgb; uchar* scanLine; int x, y; for( y=0; y<editedImage->height(); y++) { //iterate over each selected pixel in scanline scanLine = editedImage->scanLine(y); for( x=0; x<editedImage->width(); x++) { rgb = ((QRgb*)scanLine+x); redVals[qRed(*rgb)]++; greenVals[qGreen(*rgb)]++; blueVals[qBlue(*rgb)]++; } //for x } //for y //find 1% and 99% precenticles //we'll stretch these values so we avoid outliers from affecting the stretch int sumR=0; int sumG=0; int sumB=0; int indexLowR, indexHighR; int indexLowG, indexHighG; int indexLowB, indexHighB; indexLowR = -1; indexHighR = -1; indexLowG = -1; indexHighG = -1; indexLowB = -1; indexHighB = -1; for(i=0; i<256; i++) { sumR+=redVals[i]; sumG+=greenVals[i]; sumB+=blueVals[i]; //if 1% not found yet and criteria met set index if(indexLowR < 0 && sumR >= 0.01*numPixels) { indexLowR = i; } if(indexLowG < 0 && sumG >= 0.01*numPixels) { indexLowG = i; } if(indexLowB < 0 && sumB >= 0.01*numPixels) { indexLowB = i; } //if 99% not found yet and criteria met set index if(indexHighR < 0 && sumR >= 0.99*numPixels) { indexHighR = i; } if(indexHighG < 0 && sumG >= 0.99*numPixels) { indexHighG = i; } if(indexHighB < 0 && sumB >= 0.99*numPixels) { indexHighB = i; } } //run through all image pixels a second time, this time scaling coordinates as necessary for( y=0; y<editedImage->height(); y++) { //iterate over each selected pixel in scanline scanLine = editedImage->scanLine(y); for( x=0; x<editedImage->width(); x++) { //get color coordinates and convert to 0-1 scale rgb = ((QRgb*)scanLine+x); double r = ((double)qRed(*rgb) ); double g = ((double)qGreen(*rgb) ); double b = ((double)qBlue(*rgb) ); if(indexHighR != indexLowR) { r = (255*(r-indexLowR))/(indexHighR-indexLowR); } if(indexHighG != indexLowG) { g = (255*(g-indexLowG))/(indexHighG-indexLowG); } if(indexHighB != indexLowB) { b = (255*(b-indexLowB))/(indexHighB-indexLowB); } int rp = (int) QMIN( QMAX(r, 0), 255 ); int gp = (int) QMIN( QMAX(g, 0), 255 ); int bp = (int) QMIN( QMAX(b, 0), 255 ); //set adjusted color value *rgb = qRgb(rp,gp,bp); //update status bar if significant progress has been made since last update newProgress++; if(newProgress >= updateIncrement) { newProgress = 0; status->incrementProgress(); qApp->processEvents(); } } //for x } //for y //remove status bar status->setStatus( "" ); qApp->processEvents(); //return pointer to edited image return editedImage; }

---