You can get access to the uploaded file on postback operation using the UploadedFiles collection of the RadUpload editor (part of built-in GridBinaryImageColumn). From there you can manipulate the uploaded image content with your third party tool, apply the changes and then save it in the underlying source blob field.
You can use the 'First look' online demo of RadListView for reference about how to get and process the uploaded content to a database:
See the code implementation from the sample for further details. Also keep in mind that the data should be in valid binary array format in order to be saved and recognized later by RadBinaryImage.
the Telerik team