Comment by barosl

Comment by barosl 20 hours ago

25 replies

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I tested the demo at https://moq.dev/publish/ and it's buttery as hell. Very impressive. Thanks for the great technology!

Watching the Big Buck Bunny demo at https://moq.dev/watch/?name=bbb on my mobile phone leaves a lot of horizontal black lines. (Strangely, it is OK on my PC despite using the same Wi-Fi network.) Is it due to buffer size? Can I increase it client-side, or should it be done server-side?

Also, thanks for not missing South Kora in your "global" CDN map!

Twirrim 2 hours ago

Chrome on my oneplus ten, I get flickering black lines routinely. The fact they're going from somewhere along the top, down towards the right makes me wonder if it's a refresh artifact maybe? It's sort of like the rolling shutter effect

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kixelated 20 hours ago

Horizontal black lines? Dunno what that could be about, we render to a <canvas> element which is resized to match the source video and then resized again to match the window with CSS.

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  • chrismorgan 14 hours ago

    What’s that like for performance and power usage? I understand normal videos can generally be entirely hardware-accelerated so that the video doesn’t even touch the CPU, and are passed straight through to the compositor. I’m guessing with this you’re stuck with only accelerating individual frames, and there’ll be more back and forth so that resource usage will probably be a fair bit higher?

    An interesting and unpleasant side-effect of rendering to canvas: it bypasses video autoplay blocking.

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    • kixelated 13 hours ago

      It's all hardware accelerated, assuming the VideoDecoder has hardware support for the codec. VideoFrame is available in WebGL and WebGPU as a texture or gpu-buffer. We're only rendering after a`requestAnimationFrame` callback so decoded frames may get automatically skipped based on the display frame rate.

      I don't think the performance would be any worse than the <video> tag. The only exception would be browser bugs. It definitely sounds like the black bars are a browser rendering bug given it's fine when recorded.

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      • DaleCurtis 11 hours ago

        Unfortunately canvas (rgb'ish) can't overlay as efficiently as <video> (yuv'ish), so there is some power cost relative to the lowest power video overlays.

        It really only matters in long form content where nothing else on the page is changing though.

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        • chrismorgan 27 minutes ago

          > It really only matters in long form content where nothing else on the page is changing though.

          Did you not just describe at least 99% of all web video?

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    • kixelated 13 hours ago

      Oh and the autoplay restrictions for <video> don't apply when muted.

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      • chrismorgan 13 hours ago

        Depends on your configuration. Firefox has a “block audio and video” option. Which this bypasses.

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  • Numerlor 17 hours ago

    Doesn't show up on screen capture, but there's random rolling quickly flickering lines on my phone, kinda like from analog distortion on old tvs

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nine_k 11 hours ago

The page mentions a lot of Rust code and WASM. Maybe your phone's CPU cannot run WASM fast enough?

My Samsung S20 shows no black lines.

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  • TheMrZZ 7 hours ago

    My Samsung S24 Ultra shows black lines too, on Chrome and Samsung Internet.

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bb88 14 hours ago

On a mac book air m4 with a 600mbps connection, it's instantaneous and amazing.

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  • tonyhart7 11 hours ago

    with this pc spec and internet speed, I expect its "normal"

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    • cchance an hour ago

      You'd be surprised i have 1g/1g and youtube still is not buttery smooth lol on my m3 mac pro, theirs always a noticeable gap between clicking play and it actually starting to stream

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    • ofrzeta 10 hours ago

      I have the same experience on a Macbook Air M1 (I don't think that matters at all) and 100 MBit/s DSL.

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stronglikedan 20 hours ago

I don't get the black lines on Android/Chrome but it doesn't respect my aspect ratio when I go full screen. Instead of adding black bars to the sides, it excludes the top and bottom of the video completely.

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cchance 16 hours ago

Holy shit that starts streaming fast! like WTF

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