public void KirparakKaydet(string urunResimYol, string hedefDosyaYolu)

        {

            using (Image orijinalImage = Image.FromFile(urunResimYol))

            {

                int yeniGenislik = 50;

                int yeniYukseklik = 50;

                using (Bitmap yeniImage = new Bitmap(yeniGenislik, yeniYukseklik))

                {

                    yeniImage.SetResolution(orijinalImage.HorizontalResolution, orijinalImage.VerticalResolution);

                    using (Graphics g = Graphics.FromImage(yeniImage))

                    {

                        g.InterpolationMode = InterpolationMode.HighQualityBicubic;

                        g.SmoothingMode = SmoothingMode.HighQuality;

                        g.PixelOffsetMode = PixelOffsetMode.HighQuality;

                        g.CompositingQuality = CompositingQuality.HighQuality;

                        // Arka planı şeffaf yapmak için PNG formatını seçiyoruz

                        yeniImage.MakeTransparent();

                        // Yeniden boyutlandırma işlemi

                        g.DrawImage(orijinalImage, new Rectangle(0, 0, yeniGenislik, yeniYukseklik));

                        // Yeniden boyutlandırılmış resmi kaydetme

                        yeniImage.Save(hedefDosyaYolu, ImageFormat.Png);

                    }

                }

            }

        }

 public  Bitmap ResizeImage(Image image, int width, int height)

        {

            var destRect = new Rectangle(0, 0, width, height);

            var destImage = new Bitmap(width, height);

            destImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);

            using (var graphics = Graphics.FromImage(destImage))

            {

                graphics.CompositingMode = CompositingMode.SourceCopy;

                graphics.CompositingQuality = CompositingQuality.HighQuality;

                graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;

                graphics.SmoothingMode = SmoothingMode.HighQuality;

                graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;

                using (var wrapMode = new ImageAttributes())

                {

                    wrapMode.SetWrapMode(WrapMode.TileFlipXY);

                    graphics.DrawImage(image, destRect, 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, wrapMode);

                }

            }

            return destImage;

        }

  public string getBase64(Bitmap bitmap)

        {

            System.IO.MemoryStream ms = new MemoryStream();

            bitmap.Save(ms, ImageFormat.Jpeg);

            byte[] byteImage = ms.ToArray();

            var SigBase64 = Convert.ToBase64String(byteImage);

            return SigBase64;

        }

 Bitmap bitmap = ResizeImage(image, 218, 230);

 string base64 = getBase64(bitmap);