Fixing all wrong uses of RGB channels instead of the OpenCV BGR standard

doc/tutorials/imgproc/erosion_dilatation/erosion_dilatation.rst

@@ -177,7 +177,7 @@ Explanation
 
    .. container:: enumeratevisibleitemswithsquare
 
-      * Load an image (can be RGB or grayscale)
+      * Load an image (can be BGR or grayscale)
       * Create two windows (one for dilation output, the other for erosion)
       * Create a set of 02 Trackbars for each operation:
 

doc/tutorials/imgproc/histograms/histogram_comparison/histogram_comparison.rst

@@ -93,7 +93,7 @@ Code
 Explanation
 ===========
 
-#. Declare variables such as the matrices to store the base image and the two other images to compare ( RGB and HSV )
+#. Declare variables such as the matrices to store the base image and the two other images to compare ( BGR and HSV )
 
    .. code-block:: cpp
 

doc/tutorials/imgproc/imgtrans/laplace_operator/laplace_operator.rst

@@ -88,7 +88,7 @@ Code
      GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT );
 
      /// Convert the image to grayscale
-     cvtColor( src, src_gray, CV_RGB2GRAY );
+     cvtColor( src, src_gray, CV_BGR2GRAY );
 
      /// Create window
      namedWindow( window_name, CV_WINDOW_AUTOSIZE );
@@ -141,7 +141,7 @@ Explanation
 
    .. code-block:: cpp
 
-      cvtColor( src, src_gray, CV_RGB2GRAY );
+      cvtColor( src, src_gray, CV_BGR2GRAY );
 
 #. Apply the Laplacian operator to the grayscale image:
 

doc/tutorials/imgproc/imgtrans/sobel_derivatives/sobel_derivatives.rst

@@ -154,7 +154,7 @@ Code
      GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT );
 
      /// Convert it to gray
-     cvtColor( src, src_gray, CV_RGB2GRAY );
+     cvtColor( src, src_gray, CV_BGR2GRAY );
 
      /// Create window
      namedWindow( window_name, CV_WINDOW_AUTOSIZE );
@@ -217,7 +217,7 @@ Explanation
 
    .. code-block:: cpp
 
-      cvtColor( src, src_gray, CV_RGB2GRAY );
+      cvtColor( src, src_gray, CV_BGR2GRAY );
 
 #. Second, we calculate the "*derivatives*" in *x* and *y* directions. For this, we use the function :sobel:`Sobel <>` as shown below:
 

doc/tutorials/imgproc/threshold/threshold.rst

@@ -167,7 +167,7 @@ The tutorial code's is shown lines below. You can also download it from `here <h
      src = imread( argv[1], 1 );
 
      /// Convert the image to Gray
-     cvtColor( src, src_gray, CV_RGB2GRAY );
+     cvtColor( src, src_gray, CV_BGR2GRAY );
 
      /// Create a window to display results
      namedWindow( window_name, CV_WINDOW_AUTOSIZE );
@@ -221,14 +221,14 @@ Explanation
 
 #. Let's check the general structure of the program:
 
-   * Load an image. If it is RGB we convert it to Grayscale. For this, remember that we can use the function :cvt_color:`cvtColor <>`:
+   * Load an image. If it is BGR we convert it to Grayscale. For this, remember that we can use the function :cvt_color:`cvtColor <>`:
 
      .. code-block:: cpp
 
         src = imread( argv[1], 1 );
 
         /// Convert the image to Gray
-        cvtColor( src, src_gray, CV_RGB2GRAY );
+        cvtColor( src, src_gray, CV_BGR2GRAY );
 
 
    * Create a window to display the result