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• W3C Media Annotations API standard

  10 avril 2010, par silvia

  Recently, I was asked to review the W3C Media Annotations specifications as they are about to go into Last Call (a state that comes before the request for implementations at the W3C). The W3C Media Annotations group has defined a set of metadata that they believe is representative and common (...)

• The Future of the VP8 Bitstream

  18 juin 2010, par noreply@blogger.com (John Luther) — vp8

  Recently we’ve seen software products such as VLC, FFmpeg, Logitech Vid, Flumotion and Tixeo adopting and using WebM and VP8 (the video codec in WebM) in exciting new ways.

  In addition to software developers, many hardware vendors have committed to shipping VP8-accelerated products based on our current bitstream in 2011 . Devices that use hardware acceleration for video are a very small percentage of overall web traffic today, but they are a rapidly growing segment of the market and our project must be mindful of these vendors’ needs. Given the longer lead times for changes in chipsets, hardware companies implementing the codec today need to be confident that it will be stable and supported as VP8 content proliferates.

  Like every codec, WebM is not immune to change ; the difference in our project is that the improvements are publicly visible, and compatibility and implementation issues can be worked through in an open forum.

  So, to maintain codec stability while also allowing for quality and performance improvements in VP8, we have added an experimental branch to the VP8 source tree. The WebM community can use this unstable branch to propose changes to VP8 that will produce the best video codec possible, but without the constraints of a frozen bitstream. At some point in the future, when the experimental branch proves significantly better than the stable branch, we will create a new version of the codec.

  Teams dedicated to improving WebM are actively investigating and evaluating new techniques, and are committed to do so for the long term. We encourage the WebM community to keep contributing as well. To learn more about the experimental branch and get involved, see our repository layout page.

  Jim Bankoski is Codec Engineering Manager at Google.

  

• FFmpeg 0.6 ; Something About HTML5

  17 juin 2010, par Multimedia Mike — Open Source Multimedia

  The FFmpeg project made a formal release yesterday. You can download version 0.6 from the project’s download page.

  I’ve actually been seeing more news items about this today than I would have expected. This is most likely because the 0.6 release is named "Works with HTML5". Let it never be said that nerds don’t know marketing. The team really latched on to the hottest buzzword going right now.

  The name of the release refers to FFmpeg’s new native support for Google’s WebM format. It can mux and demux the WebM container, and decode the Vorbis audio, all natively (FFmpeg’s Vorbis encoder has been demoted to "experimental" for this release and it is recommended to enable libvorbis for encoding). But the big news is that this release can support Google’s libvpx natively for VP8 encoding and decoding, without having to apply any other patches.

  Getting libvpx to compile still might be a bit tricky. Fortunately, the first pass of a native, independent VP8 decoder is currently in review on the ffmpeg-devel list.