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"Live video can't be made by pushing video faster, it takes a completely differently architecture." Funnily enough, that's pretty much how HLS, the modern live

"Live video can't be made by pushing video faster, it takes a completely differently architecture." Funnily enough, that's pretty much how HLS, the modern live video standard, works - it's essentially a series of tiny video clips loaded & played one right after the other, distributed through the same CDN as normal video files. Thanks to HLS, live video is actually much worse than it was 10 years ago with RTMP in terms of latency. There's been some recent efforts in getting it down, although they're generally not standardised, hard to scale (e.g. WebRTC) and or a bit awkward.

spenczar5 7y ago
They're starting to become standardized. Apple announced LHLS, a "low latency extension" to the HLS standard, https://developer.apple.com/documentation/http_live_streaming/protocol_extension_for_low-latency_hls_preliminary_specification https://developer.apple.com/documentation/http_live_streamin.... I don't think anyone really follows Apple's spec for various technical reasons, though. Most do some sort of chunked-transfer encoding, along with pre-signaling segments in playlists, as outlined by the Periscope folks here: https://medium.com/@periscopecode/introducing-lhls-media-streaming-eb6212948bef https://medium.com/@periscopecode/introducing-lhls-media-str...
- eridius 7y ago
  > I don't think anyone really follows Apple's spec for various technical reasons, though. I would have assumed it's because Apple only announced this 4 weeks ago, and the only clients that support it are beta software.
- slimscsi 7y ago
  None follow apples spec because it’s a month old. It’s not for technical reasons. Like it or not (TBH I’m in the fence about it), it WILL be the standard.
zemnmez 7y ago
kind of? i think this is more about live replication infrastructure than the video carrier itself. with youtube, you can set up some CDNs, but with livestreaming you need to be continually ingesting and spitting out content at the same time to lots of places in the world at once
- kd5bjo 7y ago
  The video carrier can have a lot of effect over the replication properties, though. HLS is essentially a playlist of video URLs that the client fetches and stitches together, as well as refreshing the playlist to get the names of new chunks. Without an extremely specialized web server, each chink needs to be complete and published before adding it to the playlist, putting a lower bound on the overall latency of the chunk size. RTMP, on the other hand, maintains a live socket between the server and client, and the server can forward each packet as it becomes available.

spenczar5 7y ago

They're starting to become standardized. Apple announced LHLS, a "low latency extension" to the HLS standard, https://developer.apple.com/documentation/http_live_streaming/protocol_extension_for_low-latency_hls_preliminary_specification https://developer.apple.com/documentation/http_live_streamin.... I don't think anyone really follows Apple's spec for various technical reasons, though. Most do some sort of chunked-transfer encoding, along with pre-signaling segments in playlists, as outlined by the Periscope folks here: https://medium.com/@periscopecode/introducing-lhls-media-streaming-eb6212948bef https://medium.com/@periscopecode/introducing-lhls-media-str...

eridius 7y ago
> I don't think anyone really follows Apple's spec for various technical reasons, though. I would have assumed it's because Apple only announced this 4 weeks ago, and the only clients that support it are beta software.
slimscsi 7y ago
None follow apples spec because it’s a month old. It’s not for technical reasons. Like it or not (TBH I’m in the fence about it), it WILL be the standard.

zemnmez 7y ago

kind of? i think this is more about live replication infrastructure than the video carrier itself. with youtube, you can set up some CDNs, but with livestreaming you need to be continually ingesting and spitting out content at the same time to lots of places in the world at once

kd5bjo 7y ago
The video carrier can have a lot of effect over the replication properties, though. HLS is essentially a playlist of video URLs that the client fetches and stitches together, as well as refreshing the playlist to get the names of new chunks. Without an extremely specialized web server, each chink needs to be complete and published before adding it to the playlist, putting a lower bound on the overall latency of the chunk size. RTMP, on the other hand, maintains a live socket between the server and client, and the server can forward each packet as it becomes available.