HTTPUploadThroughPostEX saves invalid jpg files

gkoulouris · **Joined:** Mon Mar 28, 2011 7:19 am **Posts:** 4

When we create single-page jpgs by calling HTTPUploadThroughPost or HTTPUploadThroughPostEx, the file is saved with a jpg extension.

Windows Picture Viewer can open it, but Photoshop cannot open it.

The error is
"Could not complete your request because an unknown or invalid JPEG marker type is found"

If you view the file properties in Windows, you can see that the compression is set to CCITT T.6, which is a TIFF compression standard.

Any advice on where the problem is? I have related code snippets below:

CLIENT SIDE

Code:

WebTwain3.IfSSL = window.location.protocol == "https:";
   if (WebTwain3.IfSSL) {
      WebTwain3.HTTPPort = 443;
   }
   
   var docFormat = GetSettings("Format", "PDF");
   var docFileName = "ScannedDocument." + docFormat.toLowerCase();

   CopyToBufferForUpload();

   switch (docFormat) {
      case "JPG": WebTwain3.HTTPUploadThroughPostEx(strHostIP, 0, actionPage, docFileName, 1);
      case "TIFF": WebTwain3.HTTPUploadAllThroughPostAsMultiPageTIFF(strHostIP, actionPage, docFileName); break;
      case "PDF":
      default: WebTwain3.HTTPUploadAllThroughPostAsPDF(strHostIP, actionPage, docFileName); break;
   }

   CopyToBufferForReturn();

   if ((WebTwain3.HTTPPostResponseString).length > 0) {
      
      var queryString = WebTwain3.HTTPPostResponseString + "&nodeId=" + GetQueryString("nodeId", "0") + "&ImagesLeft=" + (WebTwain3.HowManyImagesInBuffer - LastPage.innerHTML);

      queryString += "&isQuickFinder=" + IsQuickFinder();
      var quickFinderMultipleIndex = GetQueryString("QuickFinderMultipleIndex", "0");

      queryString += "&QuickFinderMultipleIndex=" + quickFinderMultipleIndex;
      self.location = "../Add-Document.aspx" + queryString;
   }
   else {
      var errorMessage = WebTwain3.ErrorString.indexOf('Success') == 0 ? '' : WebTwain3.ErrorString;
      alert("There was a problem uploading your scanned file(s). Please try again. If the problem persists, contact support.\r\n" + errorMessage);
   }

SERVER SIDE (c#)

Code:

HttpFileCollection files = HttpContext.Current.Request.Files;
         HttpPostedFile uploadedFile = files["RemoteFile"];

         if (uploadedFile != null)
         {
            string temporaryPhysicalPath = HttpContext.Current.Server.MapPath("~" + ConfigurationManager.AppSettings["tempFileVirtualPath"]);
            string temporaryFileName = Guid.NewGuid().ToString() + System.IO.Path.GetExtension(uploadedFile.FileName);

            string contentType = "";
            switch (Path.GetExtension(uploadedFile.FileName).ToLower())
            {
               case ".tiff": contentType = "image/tiff"; break;
               case ".jpg": contentType = "image/jpeg"; break;
               case ".pdf": 
               default: contentType = "application/pdf"; break;
            }            
            string response = string.Format("?TemporaryFileName={0}&ContentType={1}&DocumentSource=Scanner", context.Server.UrlEncode(temporaryFileName), context.Server.UrlEncode(contentType));
            uploadedFile.SaveAs(temporaryPhysicalPath + temporaryFileName);
            context.Response.ContentType = "text/plain";
            context.Response.Write(response);
         }

Catherine · **Joined:** Tue Mar 08, 2005 12:23 am **Posts:** 1075

Please try changing your server side code to:

Code:

<%@ Page Language="c#" AutoEventWireup="false" Debug="True"%>

<%
    HttpFileCollection files = HttpContext.Current.Request.Files;
    HttpPostedFile uploadfile  = files["RemoteFile"];
    uploadfile.SaveAs(System.Web.HttpContext.Current.Request.MapPath(".") + "/ImageScanned/" + uploadfile.FileName);
%>

If the problem persists, you can send your problematic JPEG file to twainsupport@dynamsoft.com. We'll check it for you.

gkoulouris · **Joined:** Mon Mar 28, 2011 7:19 am **Posts:** 4

I think I figured it out.

We missed the "break" in the switch statement in the javascript. :oops:

So JPG and TIFF files were being saved using the HTTPUploadAllThroughPostAsMultiPageTIFF method

Catherine · **Joined:** Tue Mar 08, 2005 12:23 am **Posts:** 1075

Glad to hear that you figured out the problem by yourself.

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HTTPUploadThroughPostEX saves invalid jpg files

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