Video and audio speed, playback rates like Youtube

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Youtube’s channel has 0.25x to 2x speed options, on Roku 4800X. They also have other nice features (e.g. Live Chat visuals) but those are different topics.

Yet Roku doesn’t have options for playback rates: changing video and audio speeds.

How does Youtube do it?

  • Server side? Processing separate streams for each a/v rate? Tricking time stamps based on the relativity (e.g. “2x” video stream = 2x’ing current time position label)?
  • Local? Roku lower-level ability to stream-process bytes from which the video player (is it even an SG video node?) can pull from, using something I overlooked in the docs or something only made available from Roku to Google?
  • Settings tricks/hacks for bitstreams/frames/rates? As in, it would have the effect of making Roku’s audio/video adequately appear to play slower or faster? A/V streaming might have methods that are obvious to you experienced folks.

Any insight or guessing helps. :upside_down_face: :slightly_smiling_face:

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There’s an undocumented playbackSpeed property of Video nodes. I assume that’s what they’re using. From my tests, it only works on some models (4800 is one) and I haven’t figured out a way to determine which devices support it and which don’t other than trying it. It also only seems to play audio if it’s stereo, although I haven’t looked into that issue too deeply.

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Thank you!

I appreciate your insight. I’ll test it.

Too bad it’s not widespread. Adding Roku to my development set over this past month has been interesting, leaving questions I’ve tried to avoid asking before exhausting searches. I’ve abandoned prospects for most games after seeing it’s a non-starter for most types, so I recognize streaming media is the only focus.