C#: How do I convert a multi-page TIFF via MemoryStream into one long image?

Question

So I have been able to take a multi-page TIFF file and convert it to a single jpeg image but it flattens the TIFF. By flatten it, I mean it only returns the first page. The goal is to retrieve the TIFF (via memory stream), open each page of the TIFF and append it to a new jpeg (or any web image). Thus creating one long image to view on the web without the aid of a plugin. I do have the MODI.dll installed but I am not sure how to use it in this instance but it is an option.

• Source Code (using a FileHandler):

  #region multi-page tiff to single page jpeg
  var byteFiles = dfSelectedDocument.File.FileBytes; // <-- FileBytes is a byte[] or byte array source.
  
  byte[] jpegBytes;
  using( var inStream = new MemoryStream( byteFiles ) )
  using( var outStream = new MemoryStream() ) {
  System.Drawing.Image.FromStream( inStream ).Save( outStream, ImageFormat.Jpeg );
  jpegBytes = outStream.ToArray();
  }
  
   context.Response.ContentType = "image/JPEG";
   context.Response.AddHeader( "content-disposition", 
      string.Format( "attachment;filename=\"{0}\"",
      dfSelectedDocument.File.FileName.Replace( ".tiff", ".jpg" ) ) 
   );
   context.Response.Buffer = true;
   context.Response.BinaryWrite( jpegBytes );
  #endregion
  

Answer 1

I'm guessing that you'll have to loop over each frame in the TIFF.

Here's an excerpt from Split multi page tiff file:

private void Split(string pstrInputFilePath, string pstrOutputPath) 
    { 
        //Get the frame dimension list from the image of the file and 
        Image tiffImage = Image.FromFile(pstrInputFilePath); 
        //get the globally unique identifier (GUID) 
        Guid objGuid = tiffImage.FrameDimensionsList[0]; 
        //create the frame dimension 
        FrameDimension dimension = new FrameDimension(objGuid); 
        //Gets the total number of frames in the .tiff file 
        int noOfPages = tiffImage.GetFrameCount(dimension); 

        ImageCodecInfo encodeInfo = null; 
        ImageCodecInfo[] imageEncoders = ImageCodecInfo.GetImageEncoders(); 
        for (int j = 0; j < imageEncoders.Length; j++) 
        { 
            if (imageEncoders[j].MimeType == "image/tiff") 
            { 
                encodeInfo = imageEncoders[j]; 
                break; 
            } 
        } 

        // Save the tiff file in the output directory. 
        if (!Directory.Exists(pstrOutputPath)) 
            Directory.CreateDirectory(pstrOutputPath); 

        foreach (Guid guid in tiffImage.FrameDimensionsList) 
        { 
            for (int index = 0; index < noOfPages; index++) 
            { 
                FrameDimension currentFrame = new FrameDimension(guid); 
                tiffImage.SelectActiveFrame(currentFrame, index); 
                tiffImage.Save(string.Concat(pstrOutputPath, @"\", index, ".TIF"), encodeInfo, null); 
            } 
        } 
    } 

You should be able to adapt the logic above to append onto your JPG rather than create separate files.