FIX: Slow performance when you call System.Drawing.Image.FromStream to load a bitmap image (831419)


The information in this article applies to:

  • Microsoft Visual Studio .NET (2003), Enterprise Architect Edition
  • Microsoft Visual Studio .NET (2003), Enterprise Developer Edition
  • Microsoft Visual Studio .NET (2003), Academic Edition

SYMPTOMS

If you call the managed method System.Drawing.Image.FromStream to load a bitmap image, performance is significantly slower than if you load a bitmap image by using unmanaged code.

CAUSE

This performance difference occurs because the System.Drawing.Image.FromStream method always calls an image validation routine on the loaded image.

RESOLUTION

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Microsoft Visual Studio .NET 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel. 
   Date         Time   Version       Size       File name
   ---------------------------------------------------------------------
   03-Nov-2003  00:49  1.1.4322.965  2,039,808  System.Windows.Forms.dll
   03-Nov-2003  00:49  1.1.4322.965  1,703,936  System.Design.dll
   03-Nov-2003  00:47  1.1.4322.965    466,944  System.Drawing.dll

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section of this article.

MORE INFORMATION

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the Standard Terminology That Is Used to Describe Microsoft Software Updates

Hotfix Details

The following is the existing method.
System.Drawing.Image.FromStream(Stream stream, bool useICM)
This hotfix implements a new API call that has the following prototype.
System.Drawing.Image.FromStream(Stream stream, bool useICM, bool validateImageData)
If validateImageData is false, the validation routine is not called. If validateImageData is true, the validation routine is called.

Note To use the new API, the caller must have permission to run unmanaged code.
Modification Type:MinorLast Reviewed:10/25/2005
Keywords:kbHotfixServer kbQFE kbVSNET2003sp1fix kbQFE kbVSNET2003preSP1fix kbfix kbbug KB831419 kbAudDeveloper
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