Home > Image enhancement > About image enhancement
To improve OCR results and the quality of exported images, you can enhance your images before zoning and recognition using the SET tools.
Click the Enhance Image button in the Image toolbar or click Tools and choose Enhance Image to open the Image Enhancement window. You can also build Image Enhancement steps into your workflows by choosing the Enhance Images step.
Click the SET - Enhance Image button in the Image Toolbar to open the Image Enhancement window. This window has a starting image panel (1) on the left and a result panel (2) on the right. Choose a tool, then move sliders and adjust controls (3). When the result is good, click Apply (4). Discard last change (5) or Discard all changes (6) provide emergency exits. When you click Apply, the result image moves to the left panel to become the new starting image for further enhancement. Changes are listed in the History panel (7). When all changes are in order, click Page Ready (8) to have the next page loaded or Document Ready (9) to finish enhancing.
Any time you want to see what output a certain step resulted in, double click it in the History list. The display shows the result of that action, removing all actions performed afterwards. If you apply a new change to the displayed image, that replaces all changes that were made in the History list after the chosen one.
We distinguish three types of image; the last two take part in image enhancement:
Original image: The image created by your scanner or contained in a file before it enters the program. It can be color, grayscale or black-and-white.
Primary image: The state of the original image after it has been loaded into OmniPage, possibly modified by automatic or manual pre-processing operations, as displayed in the Page Image panel.
OCR image: A black-and-white image derived from the primary image, optimized for good OCR results. This can be seen in the Image Enhancement window whenever a tool is selected that affects the OCR image.
The input for Image Enhancement is either the Primary or the OCR image. Because some tools affect the Primary image, others the OCR image, you must know which image you are editing.
Click the Primary/OCR Image button in the Image Enhancement window, to switch between the primary and the OCR image in the active view.
Saving is always done on the primary image – both when saving images and when graphics are embedded in recognized pages. The OCR image cannot be saved.
This window has two panels. When you start, the primary image is displayed in the left panel as the starting image. When you make a change, the resulting image is displayed as a preview in the right panel.
Click the Apply button in the History panel when you are satisfied with your changes. This adds the change to the top of the history list. The changed image becomes the new input image on the left. Continue changing and applying as desired, then click Page Ready or Document Ready.
The History panel serves for applying or cancelling your current change. It also lets you discard changes after a given step or undo all changes made in the current enhancement session.
Use your mouse wheel to scroll page images. When the zoom tool is selected, the wheel provides a convenient way to zoom in and out on the image.
To accept all changes to the page and move to the next page:
Click Page Ready. If there are no further pages, the window is closed.
To accept all changes to the page and finish image enhancement
Click Document Ready. Any further pages in the document will not be displayed for enhancement.
To discard all changes and return to the starting image for the page:
Click the Discard All Changes button in the History panel.
To discard all changes to the page and move to the next page:
Click Cancel Page. If there are no further pages, the window is closed.
Image enhancement steps can be saved in an image enhancement template and then can be applied to similar incoming images.
Select Enable Warnings from the Tools menu to get advice during your image enhancement.
If the program appears to freeze after using the Image Enhancement window, check that you have not unintentionally minimized the window.
