add contrasts display in GUI camera settings

app/SandboxSetup/camerafocus.cpp

@@ -58,6 +58,11 @@ void CameraFocus::refreshFrame(){
     // Preview image for the user
     cv::cvtColor(rgb, gray, CV_BGR2GRAY);
     gray = setup->beamer.editContrast(gray, (double)p.getContrast(), (double)p.getBrightness());
+
+    if(displayConstrasts){
+        cvSobel(&gray);
+    }
+
     cv::cvtColor(gray, rgbFromGray, CV_GRAY2BGR);
 
     if(!crc.empty()){
@@ -129,3 +134,39 @@ void CameraFocus::on_btnReset_clicked()
 {
     loadProfil(&defaultProfil, setup->beamer.getProfil());
 }
+
+void CameraFocus::on_chbxDisplayContrast_clicked()
+{
+    displayConstrasts = ui->chbxDisplayContrast->isChecked();
+}
+
+
+cv::Mat* CameraFocus::cvSobel(cv::Mat *gray){
+
+    // From : https://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/sobel_derivatives/sobel_derivatives.html
+
+    int scale = 1;
+    int delta = 0;
+    int ddepth = CV_16S;
+    cv::Mat grad, src_gray = *gray;
+
+    /// Generate grad_x and grad_y
+    cv::Mat grad_x, grad_y;
+    cv::Mat abs_grad_x, abs_grad_y;
+
+    /// Gradient X
+    //Scharr( src_gray, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
+    cv::Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, cv::BORDER_DEFAULT );
+    cv::convertScaleAbs( grad_x, abs_grad_x );
+
+    /// Gradient Y
+    //Scharr( src_gray, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
+    cv::Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, cv::BORDER_DEFAULT );
+    cv::convertScaleAbs( grad_y, abs_grad_y );
+
+    /// Total Gradient (approximate)
+    cv::addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );
+    grad.copyTo(*gray);
+
+    return gray;
+}

app/SandboxSetup/camerafocus.h

@@ -36,16 +36,20 @@ private slots:
 
     void on_btnReset_clicked();
 
+    void on_chbxDisplayContrast_clicked();
+
 private:
     Ui::CameraFocus *ui;
     SandboxSetup *setup;
     bool state = false;
     QTimer *frameTimer;
     FrameProcessProfil defaultProfil;
+    bool displayConstrasts = false;
 
     void refreshFrame();
     void loadProfil(FrameProcessProfil *profilLoaded, FrameProcessProfil *profilSaved);
     void initCameraParams();
+    cv::Mat* cvSobel(cv::Mat *gray);
 };
 
 #endif // CAMERAFOCUS_H

app/SandboxSetup/camerafocus.ui

@@ -160,6 +160,19 @@
     <string>Reset</string>
    </property>
   </widget>
+  <widget class="QCheckBox" name="chbxDisplayContrast">
+   <property name="geometry">
+    <rect>
+     <x>80</x>
+     <y>30</y>
+     <width>131</width>
+     <height>23</height>
+    </rect>
+   </property>
+   <property name="text">
+    <string>Show Contrasts</string>
+   </property>
+  </widget>
  </widget>
  <resources/>
  <connections>