abma.x-maru.org Forum Index
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister   ProfileProfile
 Log in to check your private messages   Log inLog in 

[was Postings:Seraphim Call]
Goto page 1, 2  Next
 
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    abma.x-maru.org Forum Index -> Encoding
View previous topic :: View next topic  
Author Message
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Sun Feb 24, 2002 5:29 pm    Post subject: bad mojo! all that work, down the khazi... Reply with quote

Argh, I just knew it would happen. Right after I posted this announcement, the next ep I tried capturing developed progressive A/V sync problems about 6 or 7 minutes into the clip. By the end of the episode, the subtitles were appearing about 1 second before the accompanying audio.

Unfortunately, since these subs are already burned in, I can't do a skew adjust like in SSA, so I have to resort to capturing in 4-minute blocks, then use Premiere to match the frames and merge the blocks together. Evil or Very Mad
As a result, it may take me a little longer to post. There may also be a little more glitching in the resulting encodes where the frames don't quite match up.

I'm at a loss to explain why the sync problems are occuring; I'm capturing within Premiere, using the same profile that I used for the first 5 episodes (29.97 fps NTSC, drop-frame timecode.) If anyone has any suggestions, I'd love to hear them.
Back to top
View user's profile Send private message
oblio



Joined: 20 Feb 2002
Posts: 106
Location: Detroix, MI

PostPosted: Sun Feb 24, 2002 5:44 pm    Post subject: Reply with quote

huh. Unfortunately I can't really talk about premier as I use AVI_IO to do all my capping. Anyway, I usually see progressive audio skew when I have my framerate set to 30 (instead of 29.97). All I could recommend is to check all your settings and make sure your VCR didn't drop into PAL mode for some reason (presuming you have a dual mode VCR which is unlikely).

Hopefully someone else knows premier better...
Back to top
View user's profile Send private message Send e-mail
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Sun Feb 24, 2002 11:12 pm    Post subject: Reply with quote

Thanks for the info. Yeah, the Premiere manual does warn about making sure that the framerate is set correctly lest audio skew occur. My VCR's NTSC only; I even tried another VCR, with the same results. What's odd is that the VCR does output the episode correctly... maybe it's a munged setting in Premiere somewhere, though I've double-checked every option available.

I can't use AVI_IO, I don't believe it supports the Pinnacle DV500. Sad
Back to top
View user's profile Send private message
oblio



Joined: 20 Feb 2002
Posts: 106
Location: Detroix, MI

PostPosted: Sun Feb 24, 2002 11:16 pm    Post subject: Reply with quote

Haha! If your biggest problem is that you have a DV500, you don't have a problem. :) I'm looking longingly at the DC30, forever out of reach. :)
Back to top
View user's profile Send private message Send e-mail
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Sun Feb 24, 2002 11:51 pm    Post subject: Reply with quote

Heh. But what good is the card if it can't even capture correctly? Crying or Very sad The DC30 does look nice, I probably would've gotten that if I hadn't needed the DV inputs.
Back to top
View user's profile Send private message
Keikai



Joined: 18 Feb 2002
Posts: 178
Location: Miami, FL

PostPosted: Mon Feb 25, 2002 8:53 am    Post subject: Reply with quote

user... During my restoration and post of Dirty Pair TV, a while ago, I had to learn allot about fixing the sync on MPEGs w/ hardsubs. While the tools you'll be using will be different, if there is any way that I can help let me know. Honestly. it can get allot worse. Ep 6 of DP changed sync no less than 6 times and required about 6-7 tools (one of which I had to write) to fix.

Let me know if you need anything.
Back to top
View user's profile Send private message
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Mon Feb 25, 2002 11:34 am    Post subject: Reply with quote

Thanks, Keikai! The 4-minute captures that I'm doing now seem to be okay so far (crossing fingers); I just don't like the fact that I have to sit there and stop the cap every so often. I guess one nice side effect of this is that it's good to know I can merge two clips seamlessly (most of the time, anyway Smile).

How did you fix DP, BTW? Strip the audio then run it through an editing program to slow down or speed up certain parts of the track? Or duplicate/drop frames in the video to fit the audio?

(Hmm, I guess this thread could be moved to the Encoding forum now, but I don't know how to forward it...)
Back to top
View user's profile Send private message
Keikai



Joined: 18 Feb 2002
Posts: 178
Location: Miami, FL

PostPosted: Mon Feb 25, 2002 1:01 pm    Post subject: Reply with quote

Well in regards to how I fixed DP, I'll post an article on it to the encoding section sometime in the future (after the next FAQ revision is ready) as it was very, very involved. I had promised to do so a long time ago and never got around to it. The Zen of MPEG-1 Repair is not a hot topic these days. Ep 6 was the only exceedingly difficult one as it took me nearly a month of on-and-off attempts. (I even had to use some info I had previously gleaned from the great Avery Lee to solve that one.) I'd say in the neighborhood of 30+ hours to get it fixed (including trial and much, much error). All the other eps were a good bit easier, although eps 1-5 took me probably 6 hours apiece or so. And yes, I mention this as often as possible as I'm rather proud of the result. Wink

But as to your current problem, I'm not certain I'm fully understanding because I don't think you should need to do separate captures. Something sounds really odd. You are encoding from videotape, correct? Now does the videotape play properly synced or no? If not then you should be able to do an entire encode, demux the audio, fix it with cooledit or the like, and remux. If it is then premiere or the codec is doing something weird and we could probably fix that any number of ways.

All in all I think I'm not completely understanding the problem, but would he happy to help once I do.

p.s. What's a khazi? Smile
Back to top
View user's profile Send private message
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Mon Feb 25, 2002 1:53 pm    Post subject: Reply with quote

Yes, I'm encoding from tape. The tape itself plays properly, but somewhere in the capture process something is causing a slow skew which becomes more and more apparent as the capture goes on. Stopping the cap and restarting it restores the sync; it really sounds as if I was using an incorrect framerate like 30 fps instead of 29.97, but I'm not. I suppose I could just do the whole capture, demux the audio and try to fix it in Cooledit, but I don't feel too comfortable working with a 24-minute WAV and constantly trying to see where the audio is starting to slip. I don't think it's Premiere or the codec; the codec that's being used to cap is Pinnacle's own (pretty sure it's not MJPEG though) and I've never had problems with it before; and I haven't changed any of Premiere's settings. I don't think I have the option to use Huffyuv as the codec when capturing.

Hmm. Last night I also tried capturing using 44.1 KHz audio (I'm using 48 KHz right now), and it seemed I could go longer before the skew became too apparent. Maybe the DV500 doesn't like to deal with 48 KHz audio that well. But I'm not going to lower it to 22 KHz for perfect sync, I like good audio in my encodes. Smile

One last data point: I also tried capturing a 10-minute segment from a cartoon that was showing on one of the cable channels. As far as I could tell, syncing was perfect. So maybe it's my source tapes; when I get more time I'll try another tape...

Quote:

What's a khazi?


UK slang for a toilet, or a "bog". I just thought it sounded better. Smile
http://www.ofah.btinternet.co.uk/dictionary.htm


Last edited by user on Wed Feb 27, 2002 1:30 am; edited 1 time in total
Back to top
View user's profile Send private message
oblio



Joined: 20 Feb 2002
Posts: 106
Location: Detroix, MI

PostPosted: Mon Feb 25, 2002 3:19 pm    Post subject: Reply with quote

I'd definitely try moving the audio sample back to 44.1. Also, try to cap the whole video, then seperate out the audio into a wav file, and check to see if the lengths aren't the same. You could be getting internal AVI skew errors that are only bad in terms of headers and offsets. That would mean that resynching the split audio and video streams (with such tools as virtualdub) would correct the internal values and everything would be roses again.

Again, sorry I can't comment on premeir. I used 5 once and it scared me enough to never try again.
Back to top
View user's profile Send private message Send e-mail
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Mon Feb 25, 2002 3:45 pm    Post subject: Reply with quote

When I tried 44.1, I still found skew about 9 or 10 minutes into the ep. I'll try checking the length of the audio stream, thanks for the suggestion. It's sort of irritating that I didn't have this problem with the first 5 episodes, and all of a sudden this whole issue just pops up. Maybe I jinxed it by announcing the post before I finished all the eps. Mad

Quote:
Again, sorry I can't comment on premeir. I used 5 once and it scared me enough to never try again.


The stuff I'm doing with it right now is nowhere near Premiere's full capabilities, I suspect. I learned enough fiddling around with it to make a (crappy) music video about a year ago, then promptly forgot everything until now.
Back to top
View user's profile Send private message
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Wed Feb 27, 2002 1:52 am    Post subject: And the plot thickens... Reply with quote

Well, I finally had some time to do more experimenting today. I loaded two other tapes I had lying around (Slayers and YUA OAV) and did an 11-minute cap from each, using the same settings I've always had. Lo and behold, on playback I found no skew at all. Then I tried capping Seraphim Call ep 9 (it's on a separate tape from 6-8 ) and also found no skew. Shocked

I can only think of 3 possible causes for the problems I've been having, then:

1) the Seraphim Call source tape is somehow 'bad' and caused the capture card to flake out (similar to the way Macrovision will munge the video signal if you try to capture it)

2) I have an intermittent problem somewhere in my system or settings and by coincidence it just didn't show up when I tried capping Slayers, YUA and SC ep 9

3) the planets were in the wrong alignment when I capped SC eps 6-8


I'm hoping it's #1, for obvious reasons. Smile I wish I had the money to buy a time-base corrector, that might eliminate the problem and enhance the video signal as well. Anyway, enough rambling from me. I just hope this problem doesn't show up again (ep 8 lost sync 7 times Evil or Very Mad).
Back to top
View user's profile Send private message
Keikai



Joined: 18 Feb 2002
Posts: 178
Location: Miami, FL

PostPosted: Wed Feb 27, 2002 8:44 am    Post subject: Reply with quote

Just for the heck of it, have you tried capturing to another program? Can virtualdub encode from your capture card? This is such an intriguingly baffling problem. If it never happens again then "yey" and I guess I'd also just chock it up to a bad tape (though I still dont understand the correlation) or the planets. But if it does happen in the future let us all know. Maybe we can think of _something_ to try.
Back to top
View user's profile Send private message
user



Joined: 19 Feb 2002
Posts: 72

PostPosted: Wed Feb 27, 2002 11:07 am    Post subject: Reply with quote

I don't think AVI_IO supports my capture card, and Vdub says "no capture driver/card detected" if I try to capture within it. Pinnacle must've coded their drivers to be tightly integrated with Premiere.

I'm also not really sure about the "bad tape" explanation, but it's the best I can come up with right now. I'll try some more tapes after finishing SC. But maybe this is a sign for me to forget about VHS caps and go back to ripping DVD's. Wink
Back to top
View user's profile Send private message
oblio



Joined: 20 Feb 2002
Posts: 106
Location: Detroix, MI

PostPosted: Wed Feb 27, 2002 1:02 pm    Post subject: Reply with quote

Its all a matter of VfW vs DirectShow drivers. After some amount of usenet surfing, it looks as if you are simply screwed WRT AVI_IO (which sucks for you since it's such a fine program).

I also saw a couple threads describing your problem at the pinnacle web boards. They were suggesting that this skew was due to dropped frame treatment or problems with the card handling source frames captured from low quality tapes (this rings of "rumor and innuendo" in my professional opinion). You may want to check there. (http://webboard.pinnaclesys.com)

Have you tried capping the entire ep, stripping out the audio and video streams and checking to see if they are the same length?

-ob

PS. This is way too after the fact for you, but I solved the Analog/DV combination problem simply by purchasing seperate cards (DC10,ProDV) which work fine in the same win98 system (curse win98, but DC10 doesn't have Win2k drivers).
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    abma.x-maru.org Forum Index -> Encoding All times are GMT - 8 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group