greg schomburg

I'm attempting to get two separate computers to start playback of a movie. Each patch is playing a different movie. I'm just trying to get them to start at the same time. I'm currently using udpsend and receive and the latency seems unpredictable and a little excessive (feels like ~500 ms). I know there's plenty of network factors that can come into play (I'm currently using wifi) but before I go hard wiring I want to see what type of performance I should be expecting and if there's something else better to use. I'm currently sending a message, but I could boil that down to just an int if that would help.

I also see the same sort of latency when dealing with the simple udpsend example files.

I'm attempting to get two separate computers to start playback of a movie. Each patch is playing a different movie. I'm just trying to get t

any-tips-for-network-latency-with-udpsend-and-udpreceive

have you find an answer ? i have the same probleme

Try to sync system clock on both computers, and to sync both video players to the system clock.

I've had very good results using udpsend/udpreceive and Jascha's Landini http://www.jaschanarveson.com/pages/code.html

For that project I actually ended up not using Max. But in general I believe my main issue was latency over the wifi network. Even in the solution I went with, the wifi latency was something that needed to be solved for. If you can, always keep things hard wired. And also one other tip, never use wireless video.

For that project I actually ended up not using Max. But in general I believe my main issue was latency over the wifi network. Even in the solution I went with, the wifi latency was something that needed to be solved for. If you can, always keep things hard wired. And also one other tip, never use wireless video.
Sorry for the non solution; good luck.

Would it work to synchronise to an external clock? If your system clock is synced via NTP on both machines, try scheduling to starting the video at a specific wall clock time. Not sure how that’s done within Max.

relying to system time is a good tip - if you do, you can use time tagged control data.

wired with 100mbit/s and above, with no WAN access and while not sucking 100% CPU on both machines, you should see some 5 ms with UDP (as opposed to 500 with wifi) - so a buffer of say 50 or 100 will work most of the time.

implement "frame dropping" in the server and you are done.

wired with 100mbit/s and above, with no WAN access and while not sucking 100% CPU on both machines, you should see some 5 ms with UDP (as opposed to 500 with wifi) - so a buffer of say 50 or 100 will work most of the time.
implement "frame dropping" in the server and you are done.


*facepalm* Of course, OSC packets have timetag. I'm learning to use the odot library for OSC stuff, although there will be other ways to do it. However it's pretty easy using o.timetag, o.expr, etc. Here's an example to see what I mean:

https://github.com/CNMAT/CNMAT-odot-cpma/blob/master/extras/CNMAT-ODOT-CPMA/1_intro/07_timetags.maxpat

You'll need the odot externals, last stable release here:

https://github.com/CNMAT/CNMAT-odot/releases/tag/v1.2

https://supportnumbers.net/blog/hp-printer-assistant-not-opening/

Any Tips for Network Latency with udpsend and udpreceive