Generate Image Thumbnail

anotherThumbnail.cs

//File Upload
 // If file field isn’t empty
        if (filUpload.PostedFile != null)
        {
            // Check file size (mustn’t be 0)
            HttpPostedFile myFile = filUpload.PostedFile;
            int nFileLen = myFile.ContentLength;
            if (nFileLen == 0)
            {
                
                return;
            }

            // Check file extension (must be JPG)
            if (System.IO.Path.GetExtension(myFile.FileName).ToLower() != ".jpg")
            {
                
                return;
            }
             // Read file into a data stream
            byte[] myData = new Byte[nFileLen];
            myFile.InputStream.Read(myData, 0, nFileLen);

            // Make sure a duplicate file doesn’t exist.  If it does, keep on appending an incremental numeric until it is unique
            string sFilename = System.IO.Path.GetFileName(myFile.FileName);
            int file_append = 0;
            while (System.IO.File.Exists(Server.MapPath(sSavePath + sFilename)))
            {
                file_append++;
                sFilename = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName) + file_append.ToString() + ".jpg";
            }

            // Save the stream to disk
            System.IO.FileStream newFile = new System.IO.FileStream(Server.MapPath(sSavePath + sFilename), System.IO.FileMode.Create);
            newFile.Write(myData, 0, myData.Length);
            newFile.Close();

            // Check whether the file is really a JPEG by opening it
            System.Drawing.Image.GetThumbnailImageAbort myCallBack = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
            Bitmap myBitmap;
            
            myBitmap = new Bitmap(Server.MapPath(sSavePath + sFilename));

                // If jpg file is a jpeg, create a thumbnail filename that is unique.
                file_append = 0;
                string sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName) + sThumbExtension + ".jpg";
                while (System.IO.File.Exists(Server.MapPath(sSavePath + sThumbFile)))
                {
                    file_append++;
                    sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName) + file_append.ToString() + sThumbExtension + ".jpg";
                }

                // Save thumbnail and output it onto the webpage
                System.Drawing.Image myThumbnail = myBitmap.GetThumbnailImage(intThumbWidth, intThumbHeight, myCallBack, IntPtr.Zero);
                myThumbnail.Save(Server.MapPath(sSavePath + sThumbFile));
                imgPicture.ImageUrl = sSavePath + sThumbFile;

                // Displaying success information
                

                // Destroy objects
                myThumbnail.Dispose();
                myBitmap.Dispose();
        }
        
                
                
    	public bool ThumbnailCallback()
    	{
        	return false;
    	}

thumbnail.cs

  protected void btnsave_Click(object sender, EventArgs e)
    {
        string filename = Path.GetFileName(fileupload1.PostedFile.FileName);
        string targetPath = Server.MapPath("Images/" + filename);
        Stream strm = fileupload1.PostedFile.InputStream;
        var targetFile = targetPath;
        //Based on scalefactor image size will vary
        GenerateThumbnails(0.5, strm, targetFile);
        BindDataList();
    }
 private void GenerateThumbnails(double scaleFactor, Stream sourcePath, string targetPath)
    {
        using (var image = Image.FromStream(sourcePath))
        {
            var newWidth = (int)(image.Width * scaleFactor);
            var newHeight = (int)(image.Height * scaleFactor);
            var thumbnailImg = new Bitmap(newWidth, newHeight);
            var thumbGraph = Graphics.FromImage(thumbnailImg);
            thumbGraph.CompositingQuality = CompositingQuality.HighQuality;
            thumbGraph.SmoothingMode = SmoothingMode.HighQuality;
            thumbGraph.InterpolationMode = InterpolationMode.HighQualityBicubic;
            var imageRectangle = new Rectangle(0, 0, newWidth, newHeight);
            thumbGraph.DrawImage(image, imageRectangle);
            thumbnailImg.Save(targetPath, image.RawFormat);
        }
    }