Black and white images

The TIFF image file format is used for bi-tonal, grayscale, and full color documents. JPEG images support grayscale and color documents and PNG images support bi-tonal, grayscale. All of these image types can be converted to black and white bi-tonal images.

Some Kofax Transformation Modules background processes produce a bi-tonal version of the image on demand and in memory. For example when:

  • Displaying the black and white image in the Document Viewer or the Document Viewer (zone mode).
  • Using Image Cleanup - Image cleanup only works on a bi-tonal image. If image cleanup is attempted on a color image, it is first converted into black and white, and then cleaned up.
  • Configuring a zone - Zones also requires a black and white image. When configuring a zone, you can switch between the color image and the black and white image in the Document Viewer (zone mode). Testing a zone always displays the test results for the black and white image.

However, the Classification Set always require permanently stored black and white images for layout classification. After adding a color or grayscale image to the Classification Set, a bi-tonal version of the image is physically created and stored in a subdirectory of the project directory when training is performed.

On the Project Settings - General tab, you can specify the parameters that determine how abi-tonal image is created from a grayscale or color image. Whenever a grayscale or color image is converted to its black and white version, contrast or noise modifications are applied according to these settings. If you change these settings, you can reset any already existing black and white images for your Classification Set.