AlbumShaper  1.0a3
Macros | Functions
color.cpp File Reference
#include <qimage.h>
#include <qstring.h>
#include <qapplication.h>
#include "color.h"
#include "../../gui/statusWidget.h"
Include dependency graph for color.cpp:

Go to the source code of this file.

Macros

#define MIN(x, y)   ((x) < (y) ? (x) : (y))
 
#define MAX(x, y)   ((x) > (y) ? (x) : (y))
 

Functions

QImage * improveColorBalance (QString filename, StatusWidget *status)
 

Macro Definition Documentation

§ MAX

#define MAX (   x,
 
)    ((x) > (y) ? (x) : (y))

Definition at line 21 of file color.cpp.

Referenced by improveColorBalance().

§ MIN

#define MIN (   x,
 
)    ((x) < (y) ? (x) : (y))

Definition at line 20 of file color.cpp.

Referenced by improveColorBalance().

Function Documentation

§ improveColorBalance()

QImage* improveColorBalance ( QString  filename,
StatusWidget status 
)

Definition at line 92 of file color.cpp.

References b, editedImage, StatusWidget::incrementProgress(), MAX, MIN, newProgress, StatusWidget::setStatus(), StatusWidget::showProgressBar(), and updateIncrement.

Referenced by EditingInterface::colorBalance().

93 {
94  //load original image
95  QImage* editedImage = new QImage( filename );
96 
97  //convert to 32-bit depth if necessary
98  if( editedImage->depth() < 32 )
99  {
100  QImage* tmp = editedImage;
101  editedImage = new QImage( tmp->convertDepth( 32, Qt::AutoColor ) );
102  delete tmp; tmp=NULL;
103  }
104 
105  //setup progress bar
106  QString statusMessage = qApp->translate( "improveColorBalance", "Enhancing Color Balance:" );
107  status->showProgressBar( statusMessage, 100 );
108  qApp->processEvents();
109 
110  //update progress bar for every 1% of completion
111  const int updateIncrement = (int) ( 0.01 * editedImage->width() * editedImage->height() );
112  int newProgress = 0;
113 
114  //construct intensity histographs for each color channel
115  int redVals[256];
116  int greenVals[256];
117  int blueVals[256];
118  int i=0;
119  for(i=0; i<256; i++)
120  {
121  redVals[i] = 0;
122  greenVals[i] = 0;
123  blueVals[i] = 0;
124  }
125 
126  //populate histogram by iterating over all image pixels
127  int numPixels = editedImage->width()*editedImage->height();
128  QRgb* rgb;
129  uchar* scanLine;
130  int x, y;
131  for( y=0; y<editedImage->height(); y++)
132  {
133  //iterate over each selected pixel in scanline
134  scanLine = editedImage->scanLine(y);
135  for( x=0; x<editedImage->width(); x++)
136  {
137  rgb = ((QRgb*)scanLine+x);
138  redVals[qRed(*rgb)]++;
139  greenVals[qGreen(*rgb)]++;
140  blueVals[qBlue(*rgb)]++;
141  } //for x
142  } //for y
143 
144  //find 1% and 99% precenticles
145  //we'll stretch these values so we avoid outliers from affecting the stretch
146  int sumR=0;
147  int sumG=0;
148  int sumB=0;
149  int indexLowR, indexHighR;
150  int indexLowG, indexHighG;
151  int indexLowB, indexHighB;
152  indexLowR = -1; indexHighR = -1;
153  indexLowG = -1; indexHighG = -1;
154  indexLowB = -1; indexHighB = -1;
155  for(i=0; i<256; i++)
156  {
157  sumR+=redVals[i];
158  sumG+=greenVals[i];
159  sumB+=blueVals[i];
160 
161  //if 1% not found yet and criteria met set index
162  if(indexLowR < 0 && sumR >= 0.01*numPixels)
163  { indexLowR = i; }
164  if(indexLowG < 0 && sumG >= 0.01*numPixels)
165  { indexLowG = i; }
166  if(indexLowB < 0 && sumB >= 0.01*numPixels)
167  { indexLowB = i; }
168 
169  //if 99% not found yet and criteria met set index
170  if(indexHighR < 0 && sumR >= 0.99*numPixels)
171  { indexHighR = i; }
172  if(indexHighG < 0 && sumG >= 0.99*numPixels)
173  { indexHighG = i; }
174  if(indexHighB < 0 && sumB >= 0.99*numPixels)
175  { indexHighB = i; }
176  }
177 
178  //run through all image pixels a second time, this time scaling coordinates as necessary
179  for( y=0; y<editedImage->height(); y++)
180  {
181  //iterate over each selected pixel in scanline
182  scanLine = editedImage->scanLine(y);
183  for( x=0; x<editedImage->width(); x++)
184  {
185  //get color coordinates and convert to 0-1 scale
186  rgb = ((QRgb*)scanLine+x);
187  double r = ((double)qRed(*rgb) );
188  double g = ((double)qGreen(*rgb) );
189  double b = ((double)qBlue(*rgb) );
190 
191  if(indexHighR != indexLowR) { r = (255*(r-indexLowR))/(indexHighR-indexLowR); }
192  if(indexHighG != indexLowG) { g = (255*(g-indexLowG))/(indexHighG-indexLowG); }
193  if(indexHighB != indexLowB) { b = (255*(b-indexLowB))/(indexHighB-indexLowB); }
194 
195  int rp = (int) MIN( MAX(r, 0), 255 );
196  int gp = (int) MIN( MAX(g, 0), 255 );
197  int bp = (int) MIN( MAX(b, 0), 255 );
198 
199  //set adjusted color value
200  *rgb = qRgb(rp,gp,bp);
201 
202  //update status bar if significant progress has been made since last update
203  newProgress++;
204  if(newProgress >= updateIncrement)
205  {
206  newProgress = 0;
207  status->incrementProgress();
208  qApp->processEvents();
209  }
210 
211  } //for x
212  } //for y
213 
214  //remove status bar
215  status->setStatus( "" );
216  qApp->processEvents();
217 
218  //return pointer to edited image
219  return editedImage;
220 }
int updateIncrement
void incrementProgress()
Updates the progress bar by one step.
void showProgressBar(QString message, int numSteps)
Initializes the progress bar.
long b
Definition: jpegInternal.h:125
#define MIN(x, y)
Definition: color.cpp:20
void setStatus(QString message)
Update message.
#define MAX(x, y)
Definition: color.cpp:21
QImage * editedImage
int newProgress