/// <summary>
/// Remove speckles using Leptonica library.
/// </summary>
/// <param name="image"></param>
/// <param name="selStr"></param>
/// <param name="selSize"></param>
/// <returns></returns>
public static Bitmap RemoveSpeckles(Bitmap image, string selStr, int selSize)
{
//var sourcePixFilename = @"processing\w91frag.jpg";
using (Pix pix = PixConverter.ToPix(image))
{
PixColormap map = pix.Colormap;
pix.Colormap = null; // work around NPE during despeckle
// remove speckles
using (Pix result = pix.Despeckle(selStr, selSize))
{
if (result == null)
{
return(image);
}
return(InvertColor(PixConverter.ToBitmap(result))); // somehow, invert is needed
}
}
}
public override Pix Handle(Pix request)
{
request = request?.Despeckle(this.SelStr.ToString(), this.SelSize);
return(base.Handle(request));
}