AForge.Imaging.Filters.FiltersSequence.Apply C# (CSharp) Метод

        public void Apply( UnmanagedImage sourceImage, UnmanagedImage destinationImage )
        {
            int n = InnerList.Count;

            // check for empty sequence
            if ( n == 0 )
                throw new ApplicationException( "No filters in the sequence." );

            if ( n == 1 )
            {
                ( (IFilter) InnerList[0] ).Apply( sourceImage, destinationImage );
            }
            else
            {
                UnmanagedImage tmpImg1 = null;
                UnmanagedImage tmpImg2 = null;

                // apply the first filter
                tmpImg1 = ( (IFilter) InnerList[0] ).Apply( sourceImage );

                // apply other filters, except the last one
                n--;
                for ( int i = 1; i < n; i++ )
                {
                    tmpImg2 = tmpImg1;
                    tmpImg1 = ( (IFilter) InnerList[i] ).Apply( tmpImg2 );
                    tmpImg2.Dispose( );
                }

                ( (IFilter) InnerList[n] ).Apply( tmpImg1, destinationImage );
            }
        }
	}

 private string reconhecerCaptcha(Image img)
 {
     Bitmap imagem = new Bitmap(img);
     imagem = imagem.Clone(new Rectangle(0, 0, img.Width, img.Height), System.Drawing.Imaging.PixelFormat.Format24bppRgb);
     Erosion erosion = new Erosion();
     Dilatation dilatation = new Dilatation();
     Invert inverter = new Invert();
     ColorFiltering cor = new ColorFiltering();
     cor.Blue = new AForge.IntRange(200, 255);
     cor.Red = new AForge.IntRange(200, 255);
     cor.Green = new AForge.IntRange(200, 255);
     Opening open = new Opening();
     BlobsFiltering bc = new BlobsFiltering();
     Closing close = new Closing();
     GaussianSharpen gs = new GaussianSharpen();
     ContrastCorrection cc = new ContrastCorrection();
     bc.MinHeight = 10;
     FiltersSequence seq = new FiltersSequence(gs, inverter, open, inverter, bc, inverter, open, cc, cor, bc, inverter);
     pictureBox.Image = seq.Apply(imagem);
     string reconhecido = OCR((Bitmap)pictureBox.Image);
     return reconhecido;
 }