Iti trebuie intai cele 2 metode enumerate mai jos (iti zic doar varianta mai rapida dintre multiplele variante):

Iti va trebui de asemenea ultimul release BitMiracle.LibTiff

        private static WriteableBitmap workingWBM;
        public WriteableBitmap LoadPage(short page, Tiff timage)
        {
            FieldValue[] value = timage.GetField(TiffTag.IMAGEWIDTH);
            int width = value[0].ToInt();
            value = timage.GetField(TiffTag.IMAGELENGTH);
            int height = value[0].ToInt();

            value = timage.GetField(TiffTag.BITSPERSAMPLE);
            int bps = value[0].ToShort();

            value = timage.GetField(TiffTag.SAMPLESPERPIXEL);
            int spp = value[0].ToShort();

            int imageSize = height * width;
            int[] raster = new int[imageSize];

            timage.SetDirectory(page);
            //citim in buffer imaginea
            if (!timage.ReadRGBAImage(width, height, raster))
            {
                System.Console.Error.WriteLine("Eroare la citire (format imagine?)");
                return null;
            }

            workingWBM = new WriteableBitmap(width, height);
            //vertical flip, poveste lunga :)
            int cnt = 0;
            for (int e = height - 1; e != -1; e--)
            {
                for (int c = 0; c < width; c++)
                {
                    int red = Tiff.GetR(raster[e * width + c]);
                    int green = Tiff.GetG(raster[e * width + c]);
                    int blue = Tiff.GetB(raster[e * width + c]);
                    //Array.Copy(
                    workingWBM.Pixels[cnt] = (255 << 24) + (red << 16) + (green << 8) + (blue);
                    cnt++;
                }
            }
        //teste
            //wb.Render(
            //BitmapImage bi = new BitmapImage();
            //bi.
            //wb.Render(this.image, new MatrixTransform());
            //this.image.Source = wb;
            //timage.Close();
            return workingWBM;
        }

        public class MemTiffStream : TiffStream
        {
            public MemoryStream memStream;
            public MemTiffStream(MemoryStream ms)
                : base()
            {
                memStream = ms;
            }

            public override int Read(object clientData, byte[] buffer, int offset, int count)
            {
                return memStream.Read(buffer, offset, count);
            }

            public override void Close(object clientData)
            {
                memStream.Close();
            }

            public override long Seek(object clientData, long offset, System.IO.SeekOrigin origin)
            {
                return memStream.Seek(offset, origin);
            }

            public override long Size(object clientData)
            {
                return memStream.Length;
            }
        }


     //exemplu de usage:
     //loadOp.value este un byte[] care contine tiff-ul multi page
     this.imageControl1.Images = null;
     using (var ms = new MemoryStream())
     {
         ms.Write(loadOp.Value, 0, loadOp.Value.Length);
         ms.Position = 0;

         var mts = new MemTiffStream(ms);
         var timage = Tiff.ClientOpen("a", "r", null, mts);
         var lstimg = new List<WriteableBitmap>();
         for (short i = 0; i < timage.NumberOfDirectories(); i++)
           {
             try
             {
               var wb = LoadPage(i, timage);
               lstimg.Add(wb);
             }
             catch { }
           }
         this.imageControl1.Images = lstimg;
     }