ImageGear for .NET User Guide > Using ImageGear for .NET > Using ImageGear.Recognition Namespace > Preparing the Image for Recognition > Pre-Processing Operations > DESPECKLING |
Image despeckling relates to bitonal images. These may be imported as bitonal or may be generated, explicitly or implicitly, from grayscale or color images. Image despeckling can improve the quality of auto-zoning, recognition, and the automatic pre-processing transformations: the detection of inverted characters, skew, and orientation is more reliable when run on a despeckled bitonal image.
The method ImGearRecImage.Despeckle Method immediately despeckles a single bitonal image in the recognition engine's memory space. This functions independently of the despeckle mode setting and the resolution of the original image. The transformed image replaces the original image, keeping its format, and is available to the application.
An image despeckling mode setting is given by DespeckleMode Property, with Boolean values true and false (default: true). This mode setting influences bitonal images with a resolution of 280 dpi or greater. This mode setting is applied whenever any of the following methods are called:
When a grayscale or color image is converted to bitonal, it usually results in a cleaned image. This can be influenced by the values in SecondaryReductionMode Property and ReductionThreshold Property.
With these mode-induced transformations, the cleaned or despeckled bitonal image exists in parallel with the original one and is not available to the application.