Yep, I can confirm the same. I worked with three macs connected via LAN and a simple sync via a master works very well. Also, maybe someone could disagree, but in my experience not-compressed movies (even full DV) are lighter for the machine.
M
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.
changed the subject back to the original mail...
Marco Donnarumma wrote:
Yep, I can confirm the same. I worked with three macs connected via LAN and a simple sync via a master works very well.
this will usually give you quite a lot of jitter, since the "now" in Pd drifts in the audio-buffer (network jitter is probably neglectable in a LAN, but of course you also have that), which most likely will lead to not so smooth playback. of course it depends on the material you want to play back.
the solution we came up with, was to have a master frame clock and local frame clocks on the slaves. the slaves would adjust their framerates in order to keep up with the master, if the lag between the master clock and the slave clocks was low (some frames). if the lag was too big, the slaves would "jump" to the target value.
this worked well with several "full size" (cannot remember the actual resolution) videos played back in sync with live and taped music over 90 minutes or so.
Also, maybe someone could disagree, but in my experience not-compressed movies (even full DV) are lighter for the machine.
uncompressed video is lighter for the CPU, but more load for the harddisk. the "best" codec always depends on your system (e.g. do you have a fast RAID-system?)
fgmasdr IOhannes
Thanks for your answers. Matteo : i'm afraid it's the playback which is unsatisfying by itself ..... i' ll have to "upgrade" to better computers. Thanks also for pointing out this synchro matter, which will be necessary anyway because the videos can last as long as 15 mn.. It should be fine, hopefully, by sending a "master clock" ascending value through udp. Otherwise, if it's like hiccup, i'll keep your idea of comparing incoming values to skip / pause the needed frames.
Marco : which type of macs did you use ? Mine are fairly tired : it's both ibooks, with a 933Mhz processor.
I first tried to launch my videos using VLC with the system object, which was much lighter for the computers. But the sync is not reliable at all, and the windows blink when opening : not clean enough for my installations ...
2010/1/28 Marco Donnarumma devel@thesaddj.com
Yep, I can confirm the same. I worked with three macs connected via LAN and a simple sync via a master works very well. Also, maybe someone could disagree, but in my experience not-compressed movies (even full DV) are lighter for the machine.
M
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.
tep wrote:
Thanks for your answers. Matteo : i'm afraid it's the playback which is unsatisfying by itself ..... i' ll have to "upgrade" to better computers. Thanks also for pointing out this synchro matter, which will be necessary anyway because the videos can last as long as 15 mn.. It should be fine, hopefully, by sending a "master clock" ascending value through udp. Otherwise, if it's like hiccup, i'll keep your idea of comparing incoming values to skip / pause the needed frames.
Marco : which type of macs did you use ? Mine are fairly tired : it's both ibooks, with a 933Mhz processor.
I first tried to launch my videos using VLC with the system object, which was much lighter for the computers. But the sync is not reliable at all, and the windows blink when opening : not clean enough for my installations ...
I was thinking of trying VLC but never did, since the GEM way was much more flexible and I could create a nice interface in Pd.
I've used some very low end machines (both old macs running OSX and debian on old PCs) as slaves quite successfully. Your ibooks will probably handle DV playback adequately, especially if they are the slaves and are not doing anything else. Quicktime has handled DV very well since much effort was put in to get Final Cut Pro working smoothly on the early G4s. Try using the raw DV format rather than the .mov format, or try without audio.
Simon
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IOhannes m zmoelnig -
Marco Donnarumma -
Simon Wise -
tep