public Image EqualizeImage(Bitmap bmp, int nTreshold)
        {
            BitmapData bmpData = bmp.LockBits(new Rectangle(0,0,
                bmp.Width,bmp.Height),ImageLockMode.ReadWrite,
                PixelFormat.Format24bppRgb);
            int stride = bmpData.Stride;
            System.IntPtr Scan0 = bmpData.Scan0;

            try
            {
                unsafe
                {
                    byte *p = (byte *)(void *)Scan0;
                    int nOffset = stride - bmp.Width*3;
                    int nWidth = bmp.Width*3;
                    for(int y = 0; y < bmp.Height; ++y)
                    {
                        for(int x = 0; x < nWidth; ++x)
                        {
                            if(p[0] >= nTreshold)
                                p[0] = 255;
                            if(p[0] < nTreshold)
                                p[0] = 0;
                            ++p;
                        }
                        p += nOffset;
                    }
                }
                
            }
            catch(Exception e)
            {
                this._strErrorString = e.Message;

            }
            bmp.UnlockBits(bmpData);
            Image testImg = Image.FromHbitmap(bmp.GetHbitmap());

            return testImg;
        }