OutOfMemoryException Occurs when Inserting or Manipulating Large Images in RadRichTextBox

Updated on Sep 29, 2026

Environment

Product

RadRichTextBox for WPF

Description

RadRichTextBox uses the RadBitmap class to visualize images. RadBitmap, in turn, internally uses WriteableBitmap.

WriteableBitmap is not always efficient when populated with an extremely large image, and inserting or manipulating (for example, applying an effect to) such an image can cause a performance diminishment as well as an OutOfMemoryException.

Solution

There is currently no workaround that lets RadRichTextBox handle extremely large images without the performance and memory impact described above. Reduce the size of an image before you insert it in the document to avoid the issue.

See Also

• Getting Started