[TASK] Decouple original and working copy, add reset button.

imageviewer-qt4.cpp

@@ -74,7 +74,6 @@ void ImageViewer::initializeImage() {
 
 /**
  * In case it is needed, convert the loaded image into grayscale.
- * This is the only method modifying the original image!
  * 
  * @brief ImageViewer::convertToMonochrome
  */
@@ -83,7 +82,6 @@ void ImageViewer::convertToMonochrome() {
     logFile << "Converting image to monochrome...";
     renewLogging();
 
-    original->convertToMonochrome();
     working_copy->convertToMonochrome();
 
     updateImageDisplay();
@@ -92,6 +90,25 @@ void ImageViewer::convertToMonochrome() {
   }
 }
 
+/**
+ * No big performance, but simple.
+ * Restore the working copy based on the existing original image.
+ * 
+ * @brief ImageViewer::resetWorkingCopy 
+ */
+void ImageViewer::resetWorkingCopy() {
+  logFile << "Resetting working copy ...";
+  renewLogging();
+  for(int x=0; x<original->getImage()->width(); x++) {
+    for(int y=0; y<original->getImage()->height(); y++) {
+      working_copy->getImage()->setPixel(x, y, original->getImage()->pixel(x, y));
+    }
+  }
+  updateImageDisplay();
+  logFile << "done." << std::endl;
+  renewLogging();
+}
+
 /**
  * Draws a simple, black line.
  * @brief ImageViewer::drawBlackLine
@@ -237,24 +254,31 @@ void ImageViewer::adjustContrast(int c) {
  * @brief ImageViewer::robustAutomaticContrastAdaption
  */
 void ImageViewer::robustAutomaticContrastAdaption(void) {
-  int percentile = contrast_percentile_slider->value();
-  logFile << "Doing automatic robust contrast adaption (" << percentile << "%), hold tight... " << std::endl;
+  double* histogramm = original->getRelativeIntensityHistogramm();
+  double limit = contrast_percentile_slider->value() / 100.0;
+  logFile << "Doing automatic robust contrast adaption (" << limit << "), hold tight ..." << std::endl;
   renewLogging();
   
   // Determine upper and lower "borders"
+  double cursor;
   int lower_border = -1;
   int upper_border = -1;  
-  double limit = percentile / 100.0;
-  double cursor = 0.0;
-  double* grayscale_relative_histogramm = original->getRelativeIntensityHistogramm();
+
+  cursor = 0.0;
   for(int i=0; i<256; i++) {
-    cursor += grayscale_relative_histogramm[i];
-    if(cursor >= limit && lower_border == -1) {
-      lower_border = i-1;
+    cursor += histogramm[i];
+    if(cursor > limit) {
+      lower_border = i-1; // get last value before limit overflow
       if(lower_border < 0) lower_border = 0;
+      break;
     }
-    if(cursor >= 1-limit && upper_border == -1) {
-      upper_border = i;
+  }
+  
+  cursor = 0.0;
+  for(int i=255; i>-1; i--) {
+    cursor += histogramm[i];
+    if(cursor > limit) {
+      upper_border = i+1; // get last value before limit overflow
       if(upper_border > 255) upper_border = 255;
       break;
     }
@@ -292,7 +316,7 @@ void ImageViewer::robustAutomaticContrastAdaption(void) {
 *   
 *  GUI elements related to the tasks are set up here.
 *
-**********************contrast_percentile_slider*******************************************************************/
+*****************************************************************************************/
 
 void ImageViewer::generateControlPanels() {
   // Tab for first task
@@ -304,6 +328,10 @@ void ImageViewer::generateControlPanels() {
   monochrome->setText("Convert to monochrome");
   QObject::connect(monochrome, SIGNAL(clicked()), this, SLOT (convertToMonochrome()));
   
+  reset_working_copy = new QPushButton();
+  reset_working_copy->setText("Reset working copy");
+  QObject::connect(reset_working_copy, SIGNAL(clicked()), this, SLOT (resetWorkingCopy()));
+  
   draw_black_line = new QPushButton();
   draw_black_line->setText("Draw a black line");
   QObject::connect(draw_black_line, SIGNAL(clicked()), this, SLOT (drawBlackLine()));
@@ -322,6 +350,7 @@ void ImageViewer::generateControlPanels() {
   line_slider->setValue(3);
   //QObject::connect(lineSlider, SIGNAL(valueChanged(int)), this, SLOT (drawRainbowCross()));
   
+  task_tab1->addWidget(reset_working_copy);
   task_tab1->addWidget(monochrome);
   task_tab1->addWidget(new QLabel("Let's draw something!"));
   task_tab1->addWidget(draw_black_line);
@@ -341,7 +370,7 @@ void ImageViewer::generateControlPanels() {
  
   histogramm_label = new QLabel();
   histogramm_label->setBackgroundRole(QPalette::Base);
-  histogramm_label->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
+  histogramm_label->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
   histogramm_label->setScaledContents(false);
 
   stats = new QLabel();
@@ -379,6 +408,7 @@ void ImageViewer::generateControlPanels() {
   task_tab2->addWidget(brightness_slider);
   task_tab2->addWidget(new QLabel("Contrast"));
   task_tab2->addWidget(contrast_slider);
+  task_tab2->addWidget(new QLabel("Automatic Contrast Percentile"));
   task_tab2->addWidget(contrast_percentile_slider);
   task_tab2->addWidget(automatic_robust_contrast);
 

imageviewer-qt4.h

@@ -79,7 +79,7 @@ class ImageViewer : public QMainWindow {
     QPushButton* draw_rainbow_cross;
     QPushButton* diagonal_cross;
     QPushButton* monochrome;
-
+    QPushButton* reset_working_copy;
 
     QSlider* line_slider;
 
@@ -114,6 +114,7 @@ class ImageViewer : public QMainWindow {
     void adjustBrightness(int b);
     void adjustContrast(int c);
     void convertToMonochrome();
+    void resetWorkingCopy();
     void robustAutomaticContrastAdaption();
 
     void open();