ImageGear .NET v25.1 - Updated
Preprocess Method

ImageGear.OCR Assembly > ImageGear.OCR Namespace > ImGearOCRImage Class : Preprocess Method
Performs pre-processing steps on the image.
Public MustOverride Sub Preprocess() 
Dim instance As ImGearOCRImage
public abstract void Preprocess()
public: abstract void Preprocess(); 
abstract void Preprocess(); 

This method performs a series of image pre-processing steps. Performing these image pre-processing steps may improve the quality of the image from an OCR point of view, which may have an impact on the overall recognition accuracy for the page.

If pre-processing is desired, it should be done before performing auto-zoning and recognition. The available pre-processing steps are image inversion, despeckling, deskewing, and rotation.

Note: The image resulting from deskewing and rotation are available to the application and can be exported back to an ImGearPage object using the Export method. Inversion and despeckle run on an internal secondary image, and their result is not available for exporting back to the application. Use Invert and Despeckle methods for explicit inversion and despeckling.

Whether and how the Preprocess operation does these steps depends on the settings found in the ImGearOCR.Preprocessing object properties.

The value needed for programmed deskewing, specified with ImGearOCRDeskewMode.SET mode, can be detected by DetectSkew method and defined in the ImGearOCRPreprocessingSettings.SkewAmount property.

See Also


ImGearOCRImage Class
ImGearOCRImage Members
ImGearOCRPreprocessingSettings Class