Scanning from TWAIN and WIAXerox® DocuMate® 4790User’s Guide7-142DespeckleThis option removes speckles from the background. Speckles are small spots on an image that the scannerinterpreted as a valid part of the document. For example, an irregularity in the paper, a small wrinkle, or holeswhere a staple was removed may show up as speckles in the scanned image. The Despeckle option identifiesthese spots and removes them. This option is only available when scanning in black and white.Radius—this is the size of the area that is evaluated for stray dots.Number—this is the maximum number of dots within the radius that should be considered a speckle. If thisnumber of dots are in the circle, the dots will not be considered a speckle and remain in the image. If there areless than this number of dots in the circle, the dots are considered a speckle and removed from the image.For example, if the radius is 3 and the number is 5, then the document is evaluated in sections of 3x3 pixels and ifthere are more than 5 stray dots within a 3x3 area, they are not considered a speckle.Image EmphasisSelect how much to emphasize image content when scanning printed items. You can use Image emphasis toimprove the clarity of the scanned images by sharpening the appearance of lines within the image. The Smoothoption works best for scanning photos to keep the colors in the pictures blending smoothly together. The optionsfor Low, Medium, or High increase the sharpness of the lines in the scanned image and work best when scanningtext documents. This option is only available when scanning in Color or Gray.Here is an example of text at a 4 point font size scanned with the Image emphasis set to None and scanned asecond time with the Image emphasis set to High. The scanned examples are enlarged to show details.Note: using higher image emphasis on an item containing mixed text and image content will reduce textsharpness in favor of image clarity.Original text:ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzScanned with no image emphasis: Scanned with high image emphasis:
