Previously OpenOffice.org used Sun's Java Media Framework to play back audio and video in documents. It seemed to work well for a while, but as time went on Java became more outdated. So, developers have decided to implement the widely used GStreamer framework.
Java was problematic for customers because many distributions did not include it in default installs and almost as many didn't offer it in repositories. It could also be inconvenient or difficult for users to properly install themselves for use with OpenOffice.org. Then over time Java grew behind industry standards in decoder support as well. OpenOffice.org developers knew they needed to find a general purpose multi-platform framework available to the majority of Linux users. They found GSteamer to be a very good choice.
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