The recognition results depend a great deal on the image quality of your documents. If you're scanning very low-quality documents, Readiris will not be able to recognize them properly.
The reason for this is that Readiris works by converting pictures of text characters into actual text characters. If your documents are too dark, the characters fade into one another and create black spots. If your documents are too light, the text characters might be broken. Consequently, Readiris will not be able to recognize them.
To improve the recognition results:
- First make sure your documents have been scanned in a resolution of at least 300 dpi. If that's not the case, re-scan your documents using a proper resolution.
- Click Adjust in the Home tab. (The same command is also available on the Page tab).
Smoothen color image
This option is selected by default. It smoothens out differences in intensity, creating a greater contrast between the text and the background. Sometimes smoothening is the only way to separate text from a colored background.
For image files containing text in colored background and scanned in black and white, there is dithering (i.e. black and white spots) in the scanned black and white file, that influences the OCR quality.
Due to the fact that during the dithering process a part of the image information is lost, the resulting image after the dithering removal will not be the same as the original. However, the resulting image would improve the OCR quality.
This tool can be used only on black & white images.
Fast Binarization (Readiris Corporate)
When you selected Fast Binarization in the From File options or in the Scanner Settings, the same option is selected in the Adjust Image menu. This option is useful when scanning or opening many image files at the same time, as it increases the processing speed considerably.
When this option is selected, you cannot manually adjust the Brightness and Contrast options however. Clear this option to be able to adjust them manually.
Move the slider to increase or decrease the brightness of your documents.
Move the slider to increase or decrease the contrast between the text and the background.
Sometimes documents contain a lot of "noise" - little black spots that occur when scanning low-quality documents or using bad scanner settings.
To remove these little black spots, use the Despeckle slider. The more you move it to the right, the larger the spots that will be removed.
When you are done adjusting the image quality:
- Click Apply to preview the results.
- If the results are satisfactory, click OK. If not, change the settings again.