WebCT Good News/Bad News #4: The Media Library Tool Problems

One of the major problems we’ve encountered with CE 6.1.1 is related to Media Library collections. If you use the Media Library tool, by default, your course includes a glossary collection, but you can add other collections too. Media Library collections can include simple text entries (e.g. a text only glossary) or collections of other types of items such as text with images, images only, PDF files, audio and/or video files.

During our testing of CE 6.1.1 we discovered that Media Library collections are instantly broken if any item in a collection includes an attached image (JPEG, GIF, PNG or TIF file). Specifically, you can have a fully functional collection with images in 6.0.2 and as soon as the server is upgraded to CE 6.1.1 (in late December) the collection will be broken. Further, if a new item is added to a collection and you attach a JPEG, PNG, GIF or TIF image, the tool will be immediately broken. By broken we mean all or some of the items in a collection (which includes even a single image) will not be visible to either the student, instructor or course designer. Because you cannot see the item, you can’t detach the image or otherwise edit the collection.

Collections of other types of items (PDF files, audio or video files) do not cause the problem.

Blackboard is working on a solution; they’ve replicated the problem, and plan to provide a late January hot fix. However, once received we’ll need to test the hot fix on our test server and make a determination regarding whether it is safe to install mid-semester.

Here’s what’s happening to cause the problem:

1. When a media library collection is viewed, CE 6.1.1 inspects each entry to see if it has an image link. If it has a link, CE 6.1.1 checks for a thumbnail. If the thumbnail isn't present, CE 6.1.1 attempts to generate one. If thumbnail generation fails, CE 6.1.1 leaves the entry in its original state, and will try to generate a thumbnail again the next time the collection is accessed. All entries are in this state initially.
2. When a media library entry with an image link is added, CE 6.1.1 attempts to immediately generate a thumbnail. If thumbnail generation fails, the entry is still added, but the thumbnail is omitted. This leaves the entry in the same state as #1 above.

The error occurs when a “poorly designed SQL query” tries to generate a thumbnail for an attached image, which causes a database spike that severely effects server performance.

After applying the future hot fix (now in development by Blackboard) these issues will no longer occur. While the Media Library tool could be disabled system-wide (to prevent the problem), that action would mean that all collections (whether they included images or not) would be unavailable. So we plan to leave the Media Library tool enabled system-wide.

Here’s what you need to know and do:

1. If you have Media Library collections that do not include any images, do nothing. You and your students have dodged the bullet.
2. If all or some of your Media Library collections include images, then you have several (not very satisfactory) options. You’ll need to chose some combination of the following:

• Disable/Hide the Media library tool and don’t use it until the hot fix is installed (could be February or not until after Spring 2007 semester).
• Hide the Media Library collections with images (you can hide specific collections, but not specific entries).
• Convert all your images to PDF files, which don’t break the tool.
• Temporarily delete all images (might work if your collection is a glossary and you can temporarily do without the images—but you’ll need to re-add the images later).
• Create a series of web pages (HTML) that include the images and text from your collection(s) and create a Learning Module that serves as the repository for the collection.

We’re trying to produce a report of all Media Library collections that will be adversely effected by this bug, but you may need to just check your course(s) yourself and select a course of action. If you have questions or need help with any of the above solutions, contact your Ed Tech Center Designer.