Where does IImageFilter live in the IronBarcode API?

IImageFilter is an interface in the IronBarCode namespace, shipped in IronBarCode.dll. It extends Object and is the element type of ImageFilterCollection, which is assigned to BarcodeReaderOptions.ImageFilters.

What implements IImageFilter in IronBarcode?

The built-in filters implement it: AdaptiveThresholdFilter, BinaryThresholdFilter, BrightnessFilter, ContrastFilter, GaussianBlurFilter, BilateralFilter, SharpenFilter, MedianBlurFilter, InvertFilter, DilateFilter, ErodeFilter, and HistogramEqualizationFilter. Implement it yourself only for a custom correction step.

Interface IImageFilter

A collection of ImageFilterCollection for processing Images.

Namespace: IronBarCode

Assembly: IronBarCode.dll

Syntax

public interface IImageFilter

IImageFilter is the common contract every image-correction filter in IronBarcode satisfies, the type the reader accepts when a barcode image needs cleaning up before decoding. A developer rarely names it directly. Its value is that it lets the ImageFilterCollection hold any mix of filters in one ordered list, so brightness, contrast, blur, and threshold steps queue together and the reader applies them uniformly without knowing which concrete filter is which.

The concrete implementors shipped with IronBarcode cover the common image problems: AdaptiveThresholdFilter and BinaryThresholdFilter binarize, BrightnessFilter and ContrastFilter adjust tone, GaussianBlurFilter and BilateralFilter smooth noise, and SharpenFilter, MedianBlurFilter, InvertFilter, DilateFilter, ErodeFilter, and HistogramEqualizationFilter handle the rest. Code that needs a correction step instantiates one of these and adds it to an ImageFilterCollection, which is then assigned to BarcodeReaderOptions.ImageFilters. Implementing IImageFilter directly is reserved for a custom correction the built-in set does not provide; for everyday reads, the supplied filters are the answer.

IImageFilter filter = new ContrastFilter(2.0f);

The image correction how-to walks through the built-in filters, and the imperfect barcode example applies several to read a degraded image.