This page is in draft form and being reviewed. Comments and questions welcome!
What is the Variations System?
The Variations system has been created as a result of a series of grant-funded projects at Indiana University. Funding agencies have include included the National Science Foundation, the National Endowment for the Humanities, and the Institute for of Museum and Library Services (IMLS). As part of the IMLS grant for the Variations3 project, Indiana University has released the Variations system as open-source and helped other institutions implement the system.
The original Variations project at IU went live in 1996. The technical infrastructure was completely reworked and a new system deployed in 19952005, as a result of the Variations2 project. The IU implementation contains approximately 17,000 recordings and several hundred scores. It serves as the primary music reserves system for the Cook Music Library and the Jacobs School of Music. Every semester, students and faculty rely on Variations for thousands of reserve recordings and scores.
- Linux. The server runs on the Linux operating system (or other Unix), typically RHEL 4 or 5.
- MySql 4 5 database.
- Java. Most of Variations is written in the Java programming language. The client application can run on Windows PCs or Mac OS X.
- Darwin streaming server. This is the free version of Apple's Quicktime streaming server, which can also be used.
- Djvulibre. The free version of Djvu for score image compression and viewing.
- Flash Player. The new browser-based audio player uses Flash for the user interface.
- Apache web server.
- Tomcat web application server.
- XML. Variations makes heavy internal use of XML and uses XML for users' data files.
For audio capture and editing, commercial software products such as Sound Forge or WaveLab are typically useused, although the free Audacity can also be used.
- Linux (typically RHEL or equivalent)
- Network Alias Devices (ideally three fixed IPs)
- Firewall Configuration (opening ports for RMI, UDP, Apache, etc.)
- Java JDK
- Perl (base Perl plus numerous additional modules)
- Darwin Streaming Server
- Tomcat (if deploying Variations web player or access manager)
Although we provide step-by-step instructions for setting up Variations, inevitably there will be institutional differences requiring good troubleshooting skills and ability to get help from other experts on campus. Extra help and consulting may be needed during the process by other IT staff such as network engineers (for networking configuration, firewall and bandwidth issues), authentication specialists, authorization system integration (if basing access on course rosters), storage management (for archiving uncompressed derivatives and backing up the server), and client support for Windows and Mac (if distributing client software to end users). Installing client software on end-user-managed systems will take additional support to help users troubleshoot installation problems. If integrating the system will be integrated with a library catalog and/or z39.50 server, some library IT expertise may also need to be consulted.
- Access Policy. Who can view or listen to what content, where? Library staff typically develop an access policy (sometimes in consultation with legal counsel), but the policy needs to be review by reviewed and implemented by IT staff. An access policy may need to address student use, faculty use, source of content (library-owned or instructor-owned), recordings of an institutions's own performances, classroom use, distance education use, and textbook companion recordings. Here are some sample access policies in use (singly or in combination) at various institutions:
- Anyone on the campus VPN can access any content.
- Anyone on a computer in the music library can access any content.
- Students on the roster of a class for which the instructor has requested Variations access can access any content.
- Students on the roster of a class can only access content on the reserve list for that class.
- Items not held by the library but belonging to faculty can only be accessed by students in a class for which those items are on reserve.
- Music library staff can access any content.
- Music faculty can access any content.
- Collection Policy. What materials will be put into Variations? Will instructor-made compilation recordings or score coursepaks be digitized? Will materials for large-enrollment classes have priority? What fragile-media materials could be better-accessed via Variations? What about recordings of institutional performances?
- Discovery. How will people find out what items are available in Variations? The Variations search window only works if extensive cataloging is done to the digitized content. Most institutions choose instead to make Variations content accessible from their OPAC and/or from reserve lists.
- Workflow. How will digitizers put content in Variations while tracking their work?
- Sound quality. The Quicktime streaming can handle automatic fallback from a higher bitrate to a lower-quality one if the network connection cannot support the higher-quality streaming. So some sites encode audio at two rates, 192kbps and 28kbps. Variations can handle other bitrates as well, but 192kbps seems to be a good compromise between bandwidth and sound quality.
- Preservation Strategy. The Variations digitization process typically starts with uncompressed wav and tiff files, but it does not deliver those files. Variations is not a preservation system per se, so each institution makes a decision about whether and how to provide long-term storage the compressed master files.