Matteo Sisti Sette wrote:
tep wrote:
I'm using a few computers to play some synced videos, but i can't get satisfying results using pix_movie.
What is that is unsatisfying?
Is the playback on each computer unsatisfying by itself (in which case I cannot be of help, whatever unsatisfying means), or is the syncronization between computers that is not perfect?
In this second case, "how much" do you lose syncronization, i.e., how many frames of difference between any two computers do you accumulate per minute?
If you just send a "start" signal to all computer and have them play the videos, and expect them to keep synchronized just by the exactness of their clock, I think it is impossible (with whatever software or codec) to maintain an acceptable synchro (meaning no much more than a couple of frames of difference) for more than a few minutes.
I once had to do a synced playback of 3 videos and, if left to drift, they could stay apparently synchronized for as long as about 5 minutes. Indeed I was surprised by GEM's "clock" stability, I didn't expect so much (well actually i did, but I had been surprised a few months earlier with a similar application).
To guarantee synchro within a given tolerance "forever", I did a patch with one "master" and several (in my case 3) "slaves" where the master broadcast (via udp) its current time every N seconds (e.g. N=5) and each slave compared the received time with its own, and if the difference was greater than a threshold (e.g. 2 frames), it forced itself to skip or pause the needed amount of frames.
It worked quite well. With a slightly more sofisticated patch you could correct the drift in a more gentle way than abruptly pausing or skipping a few frames.
I used Windows (not sure whether xp or vista, I think xp) and DV-PAL codec.
By the way, I never used pix_movie's "auto" mode: I turned it off and fed the right inlet with a counter incremented by bangs taken from the [gemhead]. But i dubt this makes any difference.
I have synced several computers on a LAN successfully using a master, with a counter run by a [metro], sending frame numbers to the slaves via [netsend] and [netreceive], sending the frame number to each [pix_film] object.
This way the master can also play audio which remains in sync, and pausing, scrubbing etc are all possible.
Simon