Image Enhancement settings

Maximum allowed DPI in the output document

Choose to keep the input resolution or set a maximum limit for the output document. Use this setting to reduce output file sizes while retaining image quality.

Convert to B&W

Converts color or grayscale images to black-and-white. This option opens the Black and white and Thicken or thin settings.

• Auto threshold: Automatically defines threshold.
• Manual threshold: The value us between 0 and 255. The default value is 50.

Higher values can cause the image to be darker. The exact value that you need depends on the paper and ink on the page, and on the scanner brightness setting.

Black and white

The Black and white option allows you to remove as follows:

• Smooth characters: Smoothes the edges of text. This improves the image's appearance and reduces the file size. It removes small bumps and pits on the edges of characters. This option improves Optical Character Recognition (OCR) accuracy, improves legibility, and reduces storage needs.
• Remove halftones: Black-and-white scanned images use dithering (often called "dot shading") to simulate shades of gray. This option removes areas of dot shading, including black-on-white shading. Use this feature to change a TIFF file from grayscale to black and white.
• Remove lines: Removes all vertical and horizontal lines detected by the service. This can be useful when preparing the document for OCR.
• Despeckle: Removes speckles that are smaller than the pixel size defined in the Size in pixels field. This feature removes speckles that are not touching anything else in the image. It allows you to remove very large speckles without harming text. However, if you select a speckle size that is too large, you can unintentionally remove small text and sequences of periods, called "dot leaders," from images.

Because these operations cannot be undone, it is recommended that you initially specify a small speckle size.

Thicken or thin

Enhances scanned images that use too low a contrast threshold or too light a background. If scanned files are too light or too dark, the service enables you to thicken or thin the image:

• None
• Thin: Looks at every black pixel in the original image and removes one pixel around it. This makes single pixels "thin" into small dots.
• Thicken: Looks at every black pixel in the original image and then adds one additional pixel around it in every direction (horizontal, vertical, and along both diagonals). This makes single pixels "grow" into small dots, expanding the borders of text characters.

Color and grayscale

The Image Enhancement feature in the Color and grayscale group box can be applied to all image types. The image must be converted to black and white in order to use those functions that only work with black and white images. If the source image is already black and white, the conversion is ignored.

• Straighten page: During scanning, straightens the image using detected text as the basis for alignment. In scanned documents, corrects alignment issues.
• Auto-orient: Allows you to set the page orientation automatically.
• Remove borders: Removes borders without page cropping.
• Size in pixels: The size is between 0 and 100. The default value is 1.

Hole Punch removal

Automatically detects the location of the punch holes on the image and removes as follows: Remove left, Remove right, Remove top, and Remove bottom.