Extract imgcodecs module from highgui

doc/tutorials/introduction/display_image/display_image.rst

@@ -39,28 +39,28 @@ You'll almost always end up using the:
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 We also include the *iostream* to facilitate console line output and input. To avoid data structure and function name conflicts with other libraries, OpenCV has its own namespace: *cv*. To avoid the need appending prior each of these the *cv::* keyword you can import the namespace in the whole file by using the lines:
 
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 This is true for the STL library too (used for console I/O). Now, let's analyze the *main* function. We start up assuring that we acquire a valid image name argument from the command line.
 
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 Then create a *Mat* object that will store the data of the loaded image.
 
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 Now we call the :imread:`imread <>` function which loads the image name specified by the first argument (*argv[1]*). The second argument specifies the format in what we want the image. This may be:
 
@@ -73,7 +73,7 @@ Now we call the :imread:`imread <>` function which loads the image name specifie
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 .. note::
 
@@ -88,21 +88,21 @@ After checking that the image data was loaded correctly, we want to display our
 
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 Finally, to update the content of the OpenCV window with a new image use the :imshow:`imshow <>` function. Specify the OpenCV window name to update and the image to use during this operation:
 
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 Because we want our window to be displayed until the user presses a key (otherwise the program would end far too quickly), we use the :wait_key:`waitKey <>` function whose only parameter is just how long should it wait for a user input (measured in milliseconds). Zero means to wait forever.
 
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 Result