IsImageBlank  Method

Description         This method searches the specified device independent bitmap based on the ratio of black and white pixels on the page. This method works for only 1, 8, and 24 bit per pixel images.

Syntax                 RetVal = [BIDIB.]IsImageBlank Dib nRatio sRed sGreen sBlue

Returns               RetVal                    Long                1 if the image is blank. 0 if the image is not blank. -1 if an error occurs.

Remarks             Dib                          LONGLONG The handle of a device independent bitmap.

                            nRatio                    Long                The ratio of black and white pixels on the page in 0.1 percent units. For example 100 is 10 percent ratio black pixels on the white background. Boundary values are 0 to 1000 inclusive.

                            sRed                       Short               This parameter is noticed for only 8 and 24 bit per pixel images. This parameter contains the limit value of the red RGB component for blank page detecting.

                            sGreen                    Short               This parameter is noticed for only 8 and 24 bit per pixel images. This parameter contains the limit value of the green RGB component for blank page detecting.

                            sBlue                       Short               This parameter is noticed for only 8 and 24 bit per pixel images. This parameter contains the limit value of the blue RGB component for blank page detecting.

 

                            For example if sRed = 240, sGreen = 240, sBlue = 240 and the RGB components values of the current pixel of the image are greater than 240 then the pixel is a blank pixel.

See Also          FindBlankPage Method