FilterHarmonicMean  Method

Description         This function will filter the image by the nonlinear harmonic mean method. This function works for only monochrome, 8 bit per pixel and 24 bit per pixel images. The harmonic mean filter is member of a set of nonlinear mean filters, which are better at removing Gaussian type noise and preserving edge features than the arithmetic mean filter. The harmonic mean filter is very good at removing positive outliers. The definition of harmonic mean filter is:

where the coordinate (x+i, y+j ) is defined over the image A and the coordinate  (i, j) is defined over the N x N size square mask.


Description: 8bitgray                                          Description: harmonic

Syntax                 RetVal = [BiFilter.]FilterHarmonicMean  hDib N iShowProgress hWnd

Returns               RetVal                    LONGLONG The handle of new filtered DIB, 0 if an error occurred, or -1 if the BIFilter.dll does not installed.

Remarks             hDib                       LONGLONG Handle of the image to filter.

                            N                             short                This parameter specifies the size of the square mask. N cannot be less than 1. See the description and examples above for further information and a possible value.

                            iShowProgress       short                This parameter specifies the displaying of the progressbar and the preview dialog.

Available values:

DISPLAY_NONE (0) - The progressbar and the preview dialog will not display before filtering.

DISPLAY_PROGRESS (1) - The progressbar will display during filtering procedure.

DISPLAY_DIALOG (2) - The preview dialog will display before filtering. This dialog shows the part of the image before and after filtering.

DISPLAY_BOTH (3) - The progressbar and the preview dialog will display.

IMPORTANT: The preview dialog will only display, if there is BIDlgs32.dll installed.

                            hWnd                     LONGLONG Handler of the parent window.

See Also