AForge.Imaging.Filters.HSLFiltering.ProcessFilter C# (CSharp) Method

        protected override unsafe void ProcessFilter( UnmanagedImage image, Rectangle rect )
        {
            // get pixel size
            int pixelSize = ( image.PixelFormat == PixelFormat.Format24bppRgb ) ? 3 : 4;

            int startX  = rect.Left;
            int startY  = rect.Top;
            int stopX   = startX + rect.Width;
            int stopY   = startY + rect.Height;
            int offset  = image.Stride - rect.Width * pixelSize;

            RGB rgb = new RGB( );
            HSL hsl = new HSL( );

            bool updated;

            // do the job
            byte* ptr = (byte*) image.ImageData.ToPointer( );

            // allign pointer to the first pixel to process
            ptr += ( startY * image.Stride + startX * pixelSize );

            // for each row
            for ( int y = startY; y < stopY; y++ )
            {
                // for each pixel
                for ( int x = startX; x < stopX; x++, ptr += pixelSize )
                {
                    updated   = false;
                    rgb.Red   = ptr[RGB.R];
                    rgb.Green = ptr[RGB.G];
                    rgb.Blue  = ptr[RGB.B];

                    // convert to HSL
                    AForge.Imaging.HSL.FromRGB( rgb, hsl );

                    // check HSL values
                    if (
                        ( hsl.Saturation >= saturation.Min ) && ( hsl.Saturation <= saturation.Max ) &&
                        ( hsl.Luminance >= luminance.Min ) && ( hsl.Luminance <= luminance.Max ) &&
                        (
                        ( ( hue.Min < hue.Max ) && ( hsl.Hue >= hue.Min ) && ( hsl.Hue <= hue.Max ) ) ||
                        ( ( hue.Min > hue.Max ) && ( ( hsl.Hue >= hue.Min ) || ( hsl.Hue <= hue.Max ) ) )
                        )
                        )
                    {
                        if ( !fillOutsideRange )
                        {
                            if ( updateH ) hsl.Hue = fillH;
                            if ( updateS ) hsl.Saturation = fillS;
                            if ( updateL ) hsl.Luminance = fillL;

                            updated = true;
                        }
                    }
                    else
                    {
                        if ( fillOutsideRange )
                        {
                            if ( updateH ) hsl.Hue = fillH;
                            if ( updateS ) hsl.Saturation = fillS;
                            if ( updateL ) hsl.Luminance = fillL;

                            updated = true;
                        }
                    }

                    if ( updated )
                    {
                        // convert back to RGB
                        AForge.Imaging.HSL.ToRGB( hsl, rgb );

                        ptr[RGB.R] = rgb.Red;
                        ptr[RGB.G] = rgb.Green;
                        ptr[RGB.B] = rgb.Blue;
                    }
                }
                ptr += offset;
            }
        }
    }