On Mon, Apr 19, 2010 at 9:39 AM, Colin Guthrie <gmane at colin.guthr.ie> wrote: >> http://www.gamasutra.com/view/feature/3725/measuring_responsiveness_in_video_.php >> suggests that gamers will start noticing if the time from pressing >> a button to the time they hear a sound is above 70 to 100ms. > > That's different. Games require interaction. Taking an action produces > an effect. With music and video playback this doesn't apply until you > fast forward or rewind. But I'm interested in the game case, specifically the remotely streamed game case. > With audio or video playback in an ideal world we'd be able to buffer up > 10 - 20 seconds of data But that's not possible in a game. >> Let's say the network latency to the game server is 20ms (can't ask >> for much lower), >> and that the streaming codecs have a latency of 10ms on each end (likewise). >> The time from a button push to hearing a sound would then be 20ms up + >> 10 ms encode + 20 ms down + 10 ms decode = 60ms. ?That >> leaves all of 10 to 40 ms for local audio latency. >> So, in what way is requesting 30ms unreasonable in that scenario? > > I think I've covered that. The requirement for low latency itself for > video playback is generally invalid. AV sync does not mean playing the > video and the audio at the same time and hoping for the best. There are > clear and specific ways to get synchronisation information from PA to > deal with these scenarios. If you care about your application's power > usage and thus battery drain, then the desire for low latency should be > ditched. Are you saying that one should not play remotely streamed games using pulseaudio? I'm confused. - Dan
