3 ms·

You know what I miss? When my CRT TV would turn on in 2s, and channel switches took < 100ms.

• StavrosK 10y ago
  That was great, wasn't it? Channel switching was instant, why can't we have that now too? :/
  • nitrogen 10y ago
    It's probably because of the span between consecutive I-frames (or intra-block sweeps if not using I-frames) in the video stream, but audio should switch "instantaneously" (within 1 frame).
    • StavrosK 10y ago
      Hmm, if that were the case, wouldn't the time spent waiting be variable? That would mean that you'd sometimes get instant switches, when the I-frame was the next frame you received after the switch.
      • tinus_hn 10y ago
        It is variable, the stations are multiplexed on channels, so sometimes you can use the same stream and sometimes you have to switch. That takes time. I presume the TV hides that by always taking the same amount of time to change stations.
  • izacus 10y ago
    We managed to get zap time < 300ms on our IPTV platform, but that required A LOT of additional work configuring encoders, networking equipment and messing around with STB firmwares. There's bunch of places between the video source and you that add their own buffers (not to mention the actual I-frame issues). Usually the most critical are encoders themselves (need to generate closed GOPs and a lot of commercial expensive hardware stuff doesn't give you enough control) and the player software on STBs (those usually have large buffers pre-set). In the end it's rather large amount of work most IPTV (and digital cable) providers don't care about because... hey... where are you gonna go if you're unhappy with their service? :)