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fakob New User Dec 11, 2007, 2:26 AM Post #1 of 11 (2122 views) Shortcut capture to disk Can't Post Hi everyone. My project involves capturing video and sound to disk and then playing the clips back. but i have trouble getting the video and sound in sync. right now i have set the capture to disk actors to capture 15 seconds. but when the quicktime file is played back i notice that the sound ends around half way of the video. either the sound was captured too fast or the video was captured too slow. my recording frame rate is around 15fps. yuyf codec 640x480. does anyone has any idea what i am doing wrong? thanks fakob

jhoepffner User Dec 11, 2007, 2:03 PM Post #2 of 11 (2115 views) Shortcut Re: [fakob] capture to disk [In reply to] Can't Post Hello, During a workshop we had the same problem, with a half second lap between video and sound. We had resolved that with a Max/Msp patch,delaying the sound, with osc command to change the parameters. The sound was sended to max through soundflower. I think the same is possible with puredata. Hope that help

fakob New User Dec 13, 2007, 12:43 AM Post #3 of 11 (2098 views) Shortcut Re: [jhoepffner] capture to disk [In reply to] Can't Post hi jhoepffner thanks for the reply. the problem i have isn't the lap between audio and sound, but that due to performance reasons the sound is somehow recorded faster than the video and therefor shorter (stops earlier). right now i solved the problem in moving to a faster computer. maybe the slow computer was the problem in the first place. it looks like recording 640x480 even in yuv codec seems to be pretty processor consuming. i keep you posted about any further developements. fakob

Mark Coniglio TroikaTronix / Moderator Dec 26, 2007, 8:58 AM Post #4 of 11 (1841 views) Shortcut Re: [fakob] capture to disk [In reply to] Can't Post Are you sure that your sound input settings are set to record from the camera and _not_ the internal microphone? To get good sync, you should ensure that the sound and video are both coming from the same source -- i.e., the camera. Also, I don't think it is a good idea to set your frame rate to 15fps. I would set the frame rate to 'best'. Though I just tested 15fps with my DV camera and it worked fine. Finally, if you are recording from a DV camera, then you should leave the codec set to the native format, i.e., DV-NTSC or DV-PAL. When you switch the camera input in the Video Settings dialog, the codec should automatically come up with the default for that camera. It could be that the time taken to compress the video to yuyf codec is slowing things down thus causing the out of sync problems. That being said, I just did a 29.97 fps recording from my DV camera with the codec set to Photo JPEG and this worked fine too. I'm sorry that I can't recreate any of your problems; I'm wondering about the speed of your computer and if you are working on Mac or PC. My computer is a 2.0 GHz Core Duo Mac, and this seems to work well in terms of capturing the video with the test cases I gave above. Best Wishes, Mark - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Mark Coniglio / TroikaTronix Creator of Isadora

gavspav User Oct 20, 2008, 10:50 AM Post #5 of 11 (767 views) Shortcut Re: [Mark Coniglio] capture to disk [In reply to] Can't Post I'm using the internal i-sight and the internal mic and they are out of sync. I guess I should try an external camera. Shame though. Edit*** Just tried it with a DV Cam via Firewire * its totally out of sync! This is using a Macbook Pro Core 2 Duo. 2GB Ram. 40 GB Free Drive Space (This post was edited by gavspav on Oct 21, 2008, 12:51 AM)

ursullivision User Oct 22, 2008, 2:24 AM Post #6 of 11 (730 views) Shortcut Re: [gavspav] capture to disk [In reply to] Can't Post I had a similar problem. I ended up recording to an external drive (USB2), and my recordings were in sync (most of the time). Seems the internal drive on the mac book pro is too slow. Hope that helps. Ur ummmmmmm..........................eric

gavspav User Oct 22, 2008, 6:21 AM Post #7 of 11 (713 views) Shortcut Re: [ursullivision] capture to disk [In reply to] Can't Post Hey thanks thats definitely improved things! There is still a bit of a delay on the video side but maybe I can sort that out. Cheers Gav

ursullivision User Oct 22, 2008, 11:11 AM Post #8 of 11 (691 views) Shortcut Re: [gavspav] capture to disk [In reply to] Can't Post I've found that it's best to turn off the video in function of Isadora when recording, and, when possible to use a fast external hard drive (firewire 800 or eSata are best). I always use a DV camera, so that the audio is streaming into the computer with the video. Sometimes there is a slight video delay, but most of the time it works perfectly (I'm recording PAL 720X576). Did a few recordings today without mishap. Good luck Ur ummmmmmm..........................eric

gavspav User Oct 22, 2008, 12:21 PM Post #9 of 11 (684 views) Shortcut Re: [ursullivision] capture to disk [In reply to] Can't Post Do you mean turn the Video in Watcher off? Or the 'Start Video Input' setting (which would surely stop the capture from working?) I've tried piping the sound through soundflower so that I can put a delay on the audio. That works too! Gav

ursullivision User Oct 22, 2008, 3:17 PM Post #10 of 11 (675 views) Shortcut Re: [gavspav] capture to disk [In reply to] Can't Post i mean don't display the incoming video through Isadora as you capture it. Sorry. Ur ummmmmmm..........................eric

Mark Coniglio TroikaTronix / Moderator Nov 18, 2008, 3:30 AM Post #11 of 11 (262 views) Shortcut Re: [fakob] capture to disk [In reply to] Can't Post I am currently working on a multiple video input version of Isadora, so I will investigate the sync problems. But the bottom line is that I've seen them too in the past, and it did have a lot to do with the performance of the computer. Part of it is that whilst recording, I'm still feeding the video to Isadora itself, and this requires a "hook" into the recording process that might cause these sync problems. In any case, I'll have a look. Best Wishes, Mark - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Mark Coniglio / TroikaTronix Creator of Isadora

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