message: Fix documentation about depth combinations for imgproc functions.
diff: @@ -78,11 +78,15 @@ Input depth (src.depth()) | Output depth (ddepth)
  --------------------------|----------------------
  CV_8U | -1/CV_16S/CV_32F/CV_64F
  CV_16U/CV_16S | -1/CV_32F/CV_64F
  -CV_32F | -1/CV_32F/CV_64F
  +CV_32F | -1/CV_32F
  CV_64F | -1/CV_64F
  @note when ddepth=-1, the output image will have the same depth as the source.
  +@note if you need double floating-point accuracy and using single floating-point input data
  +(CV_32F input and CV_64F output depth combination), you can use @ref Mat.convertTo to convert
  +the input data to the desired precision.
  +
  @defgroup imgproc_transform Geometric Image Transformations
  The functions in this section perform various geometrical transformations of 2D images. They do not
  @@ -1753,7 +1757,7 @@ with the following \f$3 \times 3\f$ aperture:
  @param src Source image.
  @param dst Destination image of the same size and the same number of channels as src .
  -@param ddepth Desired depth of the destination image.
  +@param ddepth Desired depth of the destination image, see @ref filter_depths "combinations".
  @param ksize Aperture size used to compute the second-derivative filters. See #getDerivKernels for
  details. The size must be positive and odd.
  @param scale Optional scale factor for the computed Laplacian values. By default, no scaling is
  