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How would it benefit Google to re-encode every video on YouTube into VP8?

• aphyr 17y ago
  They won't recode from h264 and drop the originals immediately. There are too many hardware h264 devices out there. My guess (given how their transition from h263 went) is that youtube will add it as another encoding target and use it for their web formats as soon as flash supports it. Mobile will remain h264 in 3gp, but that's only one out of six formats.
• aphyr 17y ago
  (My earlier reply was to the original version of your comment.) It will benefit Google in two ways: First, it insulates them from encoder licensing fees going forward, and from decoder license fees if MPEG-LA decides to back off their free-for-web-streaming arrangement. It also means they're free to bundle the codec with Chrome. Second, if you believe the publishing hype, it could save them up to 50% bandwidth. I doubt it's that effective, but at Youtube's scale, processing is cheap and bandwidth is expensive; every 1% helps. If they can reduce the number of storage nodes, bytes transferred, and by extension, open conns/sec, that translates to very real savings.
• easp 17y ago
  Well, what's the licensing cost for MPEG4? It's probably per user/minute streamed, rather than a one time cost per minute of video encoded.
  • kierank 17y ago
    No charges for free web streams until 2015.
    • nailer 17y ago
      That's terrible. Imaging 'charges for images on free web streams free for the next four years'. How did that ever become acceptable?
  • ZeroGravitas 17y ago
    You pay per encoder and per decoder, both of which would adversely affect Google with their encoding farms and popular browser if the charge wasn't capped at around $5 million (I think it's gone up to just under 6 million this year) to stop the big players doing something silly like getting together and developing their own royalty-free codec. Unfortunately for that cunning plan, Google clearly sees more benefit from a codec that's compatible with the open web and open source than they do from licence discounts.
• FooBarWidget 17y ago
  Why is everybody talking about recoding? Can't they just keep the current videos as they are and encode new things in a different codec? As far as I know all the old H263 videos on Youtube have never been recoded. And why would they? Recoding H263 to H264 would just degrade quality.
  • nailer 17y ago
    I understand what you're saying, and I'd love to be educated if you know more about the topic, but aren't they both perceptual encoders? Ie, wouldn't the parts of each frame they're identifying as unimportant be quite similar? (I'm quite certain I'm wrong on this point, but I'm interested in learning why)
    • sp332 17y ago
      Each encode removes information from the video. No matter how nice the encoders are, the video quality will degrade every time.
      • nailer 17y ago
        I understand the sentence, but what I'm trying to understand is why the information removed is (significantly) different - since they're both perceptual codecs, there should be a large overlap in what is removed from the output. Eg, take a frame which has a solid chunk of blue. Codec 1 removes some of data to make things more consistent and then compresses it. Codec 2 looks at the output of codec 1, sees the consistently large blue area, doesn't see any info worth removing, and compresses it.
        • FooBarWidget 17y ago
          I don't know all the maths behind it, but try saving a JPG, close it, open it, save it again, repeat a few times. You'll see quality degrade every time you close it. My guess is that the lossy compressors try their best to preserve the previous compression artifacts, but in doing so they introduce more compression artifacts.