Like mentioned by Andrei Pavlenko after merging pullrequest #1206, a wrong

ReST directive was used. Also fixed some other ReST directives that were
not correct and removed some warnings during buildbot checks.

modules/gpu/doc/camera_calibration_and_3d_reconstruction.rst

@@ -44,11 +44,11 @@ The class also performs pre- and post-filtering steps: Sobel pre-filtering (if `
 
 This means that the input left image is low textured.
 
-.. Sample code::
+.. note::
 
-   * : A basic stereo matching example can be found at opencv_source_code/samples/gpu/stereo_match.cpp
-   * : A stereo matching example using several GPU's can be found at opencv_source_code/samples/gpu/stereo_multi.cpp
-   * : A stereo matching example using several GPU's and driver API can be found at opencv_source_code/samples/gpu/driver_api_stereo_multi.cpp
+   * A basic stereo matching example can be found at opencv_source_code/samples/gpu/stereo_match.cpp
+   * A stereo matching example using several GPU's can be found at opencv_source_code/samples/gpu/stereo_multi.cpp
+   * A stereo matching example using several GPU's and driver API can be found at opencv_source_code/samples/gpu/driver_api_stereo_multi.cpp
    
 gpu::StereoBM_GPU::StereoBM_GPU
 -----------------------------------

modules/gpu/doc/image_filtering.rst

@@ -5,9 +5,9 @@ Image Filtering
 
 Functions and classes described in this section are used to perform various linear or non-linear filtering operations on 2D images.
 
-.. Sample code::
+.. note::
 
-   * : An example containing all basic morphology operators like erode and dilate can be found at opencv_source_code/samples/gpu/morphology.cpp
+   * An example containing all basic morphology operators like erode and dilate can be found at opencv_source_code/samples/gpu/morphology.cpp
 
 gpu::BaseRowFilter_GPU
 ----------------------

modules/gpu/doc/image_processing.rst

@@ -966,9 +966,9 @@ Composites two images using alpha opacity values contained in each image.
 
     :param stream: Stream for the asynchronous version.
 
-.. Sample code::
+.. note::
 
-   * : An example demonstrating the use of alphaComp can be found at opencv_source_code/samples/gpu/alpha_comp.cpp
+   * An example demonstrating the use of alphaComp can be found at opencv_source_code/samples/gpu/alpha_comp.cpp
 
 gpu::Canny
 -------------------
@@ -1030,9 +1030,9 @@ Finds lines in a binary image using the classical Hough transform.
 
 .. seealso:: :ocv:func:`HoughLines`
 
-.. Sample code::
+.. note::
 
-   * : An example using the Hough lines detector can be found at opencv_source_code/samples/gpu/houghlines.cpp
+   * An example using the Hough lines detector can be found at opencv_source_code/samples/gpu/houghlines.cpp
 
 gpu::HoughLinesDownload
 -----------------------

modules/gpu/doc/object_detection.rst

@@ -62,12 +62,12 @@ The class implements Histogram of Oriented Gradients ([Dalal2005]_) object detec
 
 Interfaces of all methods are kept similar to the ``CPU HOG`` descriptor and detector analogues as much as possible.
 
-.. Sample code::
+.. note::
 
-   * : An example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/cpp/peopledetect.cpp
-   * : A GPU example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/gpu/hog.cpp
+   * An example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/cpp/peopledetect.cpp
+   * A GPU example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/gpu/hog.cpp
 
-   * : PYTHON : An example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/python2/peopledetect.py
+   * (Python) An example applying the HOG descriptor for people detection can be found at opencv_source_code/samples/python2/peopledetect.py
 
 gpu::HOGDescriptor::HOGDescriptor
 -------------------------------------
@@ -235,10 +235,10 @@ Cascade classifier class used for object detection. Supports HAAR and LBP cascad
             Size getClassifierSize() const;
     };
 
-.. Sample code::
+.. note::
 
-   * : A cascade classifier example can be found at opencv_source_code/samples/gpu/cascadeclassifier.cpp
-   * : A Nvidea API specific cascade classifier example can be found at opencv_source_code/samples/gpu/cascadeclassifier_nvidia_api.cpp
+   * A cascade classifier example can be found at opencv_source_code/samples/gpu/cascadeclassifier.cpp
+   * A Nvidea API specific cascade classifier example can be found at opencv_source_code/samples/gpu/cascadeclassifier_nvidia_api.cpp
 
 gpu::CascadeClassifier_GPU::CascadeClassifier_GPU
 -----------------------------------------------------

modules/gpu/doc/video.rst

@@ -3,10 +3,10 @@ Video Analysis
 
 .. highlight:: cpp
 
-.. Sample code::
+.. note::
 
-   * : A general optical flow example can be found at opencv_source_code/samples/gpu/optical_flow.cpp
-   * : A feneral optical flow example using the nvidia API can be found at opencv_source_code/samples/gpu/opticalflow_nvidia_api.cpp
+   * A general optical flow example can be found at opencv_source_code/samples/gpu/optical_flow.cpp
+   * A general optical flow example using the Nvidia API can be found at opencv_source_code/samples/gpu/opticalflow_nvidia_api.cpp
    
 gpu::BroxOpticalFlow
 --------------------
@@ -47,9 +47,9 @@ Class computing the optical flow for two images using Brox et al Optical Flow al
         GpuMat buf;
     };
 
-.. Sample code::
+.. note::
 
-   * : An example illustrating the Brox et al optical flow algorithm can be found at opencv_source_code/samples/gpu/brox_optical_flow.cpp
+   * An example illustrating the Brox et al optical flow algorithm can be found at opencv_source_code/samples/gpu/brox_optical_flow.cpp
 
 gpu::GoodFeaturesToTrackDetector_GPU
 ------------------------------------
@@ -218,9 +218,9 @@ The class can calculate an optical flow for a sparse feature set or dense optica
 
 .. seealso:: :ocv:func:`calcOpticalFlowPyrLK`
 
-.. Sample code::
+.. note::
 
-   * : An example of the Lucas Kanade optical flow algorithm can be found at opencv_source_code/samples/gpu/pyrlk_optical_flow.cpp
+   * An example of the Lucas Kanade optical flow algorithm can be found at opencv_source_code/samples/gpu/pyrlk_optical_flow.cpp
 
 gpu::PyrLKOpticalFlow::sparse
 -----------------------------
@@ -425,9 +425,9 @@ The class discriminates between foreground and background pixels by building and
 
 .. seealso:: :ocv:class:`BackgroundSubtractorMOG`
 
-.. Sample code::
+.. note::
 
-   * : An example on gaussian mixture based background/foreground segmantation can be found at opencv_source_code/samples/gpu/bgfg_segm.cpp
+   * An example on gaussian mixture based background/foreground segmantation can be found at opencv_source_code/samples/gpu/bgfg_segm.cpp
 
 gpu::MOG_GPU::MOG_GPU
 ---------------------
@@ -706,9 +706,9 @@ The class uses H264 video codec.
 
 .. note:: Currently only Windows platform is supported.
 
-.. Sample code::
+.. note::
 
-   * : An example on how to use the videoWriter class can be found at opencv_source_code/samples/gpu/video_writer.cpp
+   * An example on how to use the videoWriter class can be found at opencv_source_code/samples/gpu/video_writer.cpp
 
 gpu::VideoWriter_GPU::VideoWriter_GPU
 -------------------------------------
@@ -921,9 +921,9 @@ Class for reading video from files.
 
 .. note:: Currently only Windows and Linux platforms are supported.
 
-.. Sample code::
+.. note::
 
-   * : An example on how to use the videoReader class can be found at opencv_source_code/samples/gpu/video_reader.cpp
+   * An example on how to use the videoReader class can be found at opencv_source_code/samples/gpu/video_reader.cpp
 
 gpu::VideoReader_GPU::Codec
 ---------------------------