jfjoch_viewer: Improve HDR mode

viewer/toolbar/JFJochViewerToolbarDisplay.cpp

@@ -21,6 +21,11 @@ JFJochViewerToolbarDisplay::JFJochViewerToolbarDisplay(QWidget *parent)
     auto_foreground_button->setChecked(false);
     addWidget(auto_foreground_button);
 
+    hdr_mode_button = new QPushButton("HDR");
+    hdr_mode_button->setCheckable(true);
+    hdr_mode_button->setChecked(false);
+    addWidget(hdr_mode_button);
+
     addWidget(new QLabel("&nbsp;&nbsp;<b>Color map</b>&nbsp;&nbsp;"));
 
     // Initialize QComboBox with the options
@@ -41,7 +46,7 @@ JFJochViewerToolbarDisplay::JFJochViewerToolbarDisplay(QWidget *parent)
     connect(color_map_select, QOverload<int>::of(&QComboBox::currentIndexChanged),
             this, &JFJochViewerToolbarDisplay::colorComboBoxSet);
     connect(auto_foreground_button, &QPushButton::clicked, this, &JFJochViewerToolbarDisplay::autoForegroundButtonPressed);
-
+    connect(hdr_mode_button, &QPushButton::clicked, this, &JFJochViewerToolbarDisplay::HDRModeButtonPressed);
     auto *stretch = new QWidget(this);
     stretch->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
     addWidget(stretch);
@@ -60,7 +65,6 @@ void JFJochViewerToolbarDisplay::colorComboBoxSet(int val) {
     emit colorMapChanged(val);
 }
 
-
 void JFJochViewerToolbarDisplay::autoForegroundButtonPressed() {
     emit setAutoForeground(auto_foreground_button->isChecked());
 }
@@ -70,15 +74,18 @@ void JFJochViewerToolbarDisplay::updateAutoForeground(bool val) {
     auto_foreground_button->setChecked(val);
 }
 
+void JFJochViewerToolbarDisplay::HDRModeButtonPressed() {
+    emit setHDRMode(hdr_mode_button->isChecked());
+}
+
 void JFJochViewerToolbarDisplay::imageLoaded(std::shared_ptr<const JFJochReaderImage> image) {
     if (image) {
         auto valid = image->ValidMinMax();
-        if (valid.has_value())
+        if (valid.has_value() && valid->second > 1)
             foreground_slider->setMax(valid->second);
         else
             foreground_slider->setMax(MAX_SLIDER_NO_IMAGE);
     } else {
         foreground_slider->setMax(MAX_SLIDER_NO_IMAGE);
     }
-
 }