Audio and video out of sync

[pvh1987]

Hi

I am capturing old VHS video with a standard VCR plugged into an older Pinnacle TV Tuner Card using composite and audio captured with on board soundcard. I am using VirtualVCR.

No matter what AV Sync settings I use in VirtualVCR, the result is out of sync. The big problem is that it will be perfect in the beginning of the video and in the end it off by 200 ms or even more (the video is about 40 min long). I can't figure out how to correct this.

I am using the Huffyuv codec for video (PAL 25 fps, 720x576) and the audio is PCM 16bit at 48kHz.

I would like to know the source of the problem. I cannot be true that I have to correct every capture - It will take a very long time because the out-of-sync is not constant. What can I do to ensure total sync without doing nasty frame rates or audio sample rate? I am mastering for DVD so I want the quality as perfect as possible.

And a second question. I am capturing composite video using a very high quality cable and high quality SCART-converter plug. Still, there is some flickering noise on the picture. I am not talking about interlaced video - it is like a bad TV signal. Is the tuner card not good enough? It gets a lot worse using S-Video. I guess my VCR is not capable of outputting S-Video correctly.

I can live with the slight video noise if I get the audio/video sync to work.

Any help is appreciated. Thank you very much

[pvh1987]

By the way - I had no frame dropping during capture if that is important. I am using a fast computer so I simply can't figure out why there should be any problems at all.

[lordsmurf]

Originally Posted by pvh1987

By the way - I had no frame dropping during capture if that is important. I am using a fast computer so I simply can't figure out why there should be any problems at all.

Yes, this is VERY important to know. Most sync errors are caused by random frame loss.

I wonder if your system is accurately reporting frame loss, however. I've seen that too, where the capture software was making a mistake.

Double-check yourself against this guide: http://www.digitalfaq.com/guides/vid...ped-frames.htm

If you're still sure there are no dropped frames, then look at other areas. For example, how do you know there is an audio sync error? Maybe your player software is at fault. I'll assume you've not yet edited/authored it (and therefore not made a DVD to watch on TV).

[setarip_old]

Hi!

Have you considered the possibility that your VCR might be at fault (stretched tape, dirty heads, etc.)?

[manolito]

Try VirtualDub!

I spent a lot of time resolving AV sync issues in a very similar scenario. VirtualVCR can repair sync issues, but only to a certain amount. Then it just gives up.

My experience with VirtualDub is very good. I have a very slow computer, and capturing to Huffyuv does not work because the I/O bus cannot take the data rate. PicVideo MJPEG codec at quality 19 is the maximum my computer can take. And I have to capture "blind", i.e. I have to tell VDub to not display the image during capturing.

But the AV sync routines in VDub are excellent, even with a badly damaged tape I do get perfect sync.

Good luck
manolito

[pvh1987]

Actually, I used VirtualDub the first time. It crashed when I started to record. It crashed so bad I could not close the program even when using task mananger several times. I needed to reboot before being able to use any other capture software.

I might try it again anyway.

Maybe I should get a dedicated video grabber instead of a TV Tuner combo to get a cleaner video signal? There is a lot of cheap stuff out there, I see. Even with USB2 connection. Do you think it will be better than my current TV Card? I think it is a Pinnacle PCTV Pro: http://images.anewbiz.net/EbayPics/V..._PC_TV_Pro.jpg

I am totally sure that my videotape is in perfect condition. It has been stored in a normal room and only played a few times.

Is it easy to use a video grabber with VirtualDub/VirtualVCR or similiar free software?

I want to know if I should just stick to my current card or get a better one to get rid of the sync problems and hopefully get a cleaner video capture?

Thanks for the help so far

[lordsmurf]

You just said the "p" word. I don't suggest products from that company, no. It rarely ends on a positive note, for most people, with the consumer products.

Have you considered trying uncompressed capturing, just to see what happens? I've seen huffyUV cause out-of-sync issues before, with no dropped frames.

[pvh1987]

Well, I guess I should just buy a better card from another company and then start from there.

Is there any card or USB-stick that you guys will recommend? I guess it should be based on a bt8x8 chip - looks like it is very supported. I am open to everything else, but I want to use it with free capture software.

I don't care if it has a tv-tuner as well - but it is very important that the composite input will produce a clean sharp picture at 720x576 PAL. I know that composite is not the most hifi connection to use, but it is the one I will be using for digitizing my VHS tapes.

I really hope to get some advice here - I would like to get started soon. It is time consuming work so I would like the very best quality from a consumer card - don't want to use a lot of money just to digitize VHS.

[lordsmurf]

Does it have to be a PCI card? Is an AGP card possible? (Not PCI express.)
Budget?
Location?

I can surely help.

[Ghitulescu]

Unless you have a special need for that recording, I would suggest you something else.

I did very long time ago PC captures and I always have more or less problems. Not dropped frames, or asynch, but color space errors, driver resizing (capture window), frame interpolation (so they don't report a dropped frame but create an artificial one instead), things that most people do not notice. Because I'm a perfectionist.

For some 7 years now I use the hardware way, I capture to a DVD recorder (well, it's a good one) using a studio SVHS feeder (there are also other gear in between). So I don't care about anything (I live in PAL land, so most NTSC issues are moot), drivers, software, HDD, graphic card - the engineers did it for me. Cutting I do frame accurate (it's possible also on MPEG-2 files). Transitions, I don't need. Image improvers, I do in hardware (for things only the software can do, it's not worth capturing, unless the tapes are unicate). Bingo.
If you care about that tape, then rent (or buy used) a good VCR and a good DVD recorder. Don't forget the TBC, you'll desperately need one. Or use the VHS->DVD services of a professional lab - if it's an one-time job.

[pvh1987]

I don't want a DVD or harddisk recorder. Maybe in the future so I can capture digital TV streams in MPEG2 and MPEG4 with no loss.

I simply want a device that will let me capture analog video and put it into a 720x576 25fps PAL uncompressed (or nearly uncompressed) video file.

I live in Denmark. My budget is like $100-200 for the moment. Right know, I only want to capture VHS, so reference grade equipment is not needed.

Well, I am a high end hifi freak so I am kind of a perfectionist myself, but I want to use the money where it matters and I really can't see why I should by an expensive device from Canopus or something like that, just to capture som old VHS with reasonable quaility and synced audio/video.

I have no need to output analog video. Only input is needed.

My old school had a Dazzle-device that would capture analog video and audio and turn it into a DV-file using Adobe Premiere (I guess another DV capture program could be used instead). I never tried it, but I guess it worked just fine. DV must be good enough for SD video. I don't know about sound, but if it's synced to the video, I could record the sound again with a dedicated soundcard and sync the audio stream to the other DV-audio stream. Maybe that's the way to go?

The TV-card solution is a bit messy to me, but if it works and have just as good quality (or better) - that will be fine.

For postprocessing I want to split and cut, maybe deinterlacing as well. That can be done with avisynth, so I don't need any fancy video editing software.

Again - thanks a lot for helping me with this

[zilog jones]

Originally Posted by pvh1987

My old school had a Dazzle-device that would capture analog video and audio and turn it into a DV-file using Adobe Premiere (I guess another DV capture program could be used instead). I never tried it, but I guess it worked just fine. DV must be good enough for SD video. I don't know about sound, but if it's synced to the video, I could record the sound again with a dedicated soundcard and sync the audio stream to the other DV-audio stream. Maybe that's the way to go?

DV should be more than enough for VHS, you can try this if it is an available option.

For postprocessing I want to split and cut, maybe deinterlacing as well. That can be done with avisynth, so I don't need any fancy video editing software.

Why would you need to de-interlace? What is your destination format going to be? If it is DVD it will be unecessary.

Have you tried getting the latest drivers for your TV card? It is very odd that it made VirtualDub crash like that - are you using the latest version of that too? What kind of specs is your PC?

I have a Pinnacle PCTV Stereo and have had very little trouble with it. Mine is a Philips SAA7134 based card though - if yours is exactly like the picture you linked to it has some sort of Connexant chip which means it is probably a completely unrelated card.

Although this will probably not solve your capturing problem, I would highly recommend investing in a decent high-end S-VHS VCR with a built-in TBC. It doesn't have to be a professional deck - I have a Panasonic NV-HS960 which was one of the top of the range consumer models circa 2000 and am very happy with results. You can easily get something like this for <€100 on eBay. However if it's just for the one cassette it's probably not worth it.

Originally Posted by Ghitulescu

...SVHS feeder...

Do you mean a VCR?

Originally Posted by Ghitulescu

...unless the tapes are unicate..

What do you mean by "unicate"?

[pvh1987]

I just downloaded the latest VirtualDub. Now the capture works - at least it has not crashed yet.

I also tried capturing with no compression (YUV2-capture). The audio and video was not sync at all. Even for a capture less than a minute long. This drives me crazy

I looked at the stats and I could see, that the capture process used between 0 and 6% CPU. The frame rate was not exactly 25, just a little faster like 25.000345 or something. This was changing all the time, but always a little faster than it should be. I guess there is no need to worry about that.

The audio was captured at 48008 Hz? That is strange... it should capture at 48000 precisely. Maybe that's why the audio doesn't match with the video over time, because it is played back at 48000 Hz but captured at 48008? That could explain it.

However, it does not explain why the audio and video was way out of sync in my uncompressed capture.

I really feel like an idiot wasting time on some really bad equipment - how hard can it be to transfer some old VHS to DVD with reasonable quality? Very hard, it shows

Right now I have a fear of buying another TV card and get the same results.

I would like a device like Canopus ADVC 55, but that's just too expensive for the few tapes I need to capture. If anybody know a cheaper alternative, I would like to know about it.

Of course, I am still open to TV card solutions if I get my sync problems fixed. Maybe some of you have some ideas about the audio captured at 48008 Hz?

[Ghitulescu]

Originally Posted by zilog jones

Do you mean a VCR?

Yes, there are several flavours of VCR, the workhorse is called a feeder - you know, that type that gives you the exact frame even after hundreds of FWD/REW. It doesn't record, because it's a player.

Unicate - well, all family tapes are unicate, because nobody else has a copy of them
Or one-time shows.

[pvh1987]

Update: I tried capturing in VirtualDub again, and this time the audio sample rate was changing from being way off and then nearly 48000 after a while. It still looks like it is running too fast, like between 48000 and 48010 Hz.

[lordsmurf]

I never got an answer on AGP vs PCI. ATI All In Wonder cards can work very well for this. And I have a few spares.

Converting video is harder than you think, assuming you care about quality.

For a small project, you may as well pay a pro service. The cost can come out the same in the end.

[lordsmurf]

On the consumer side, "locked audio" has turned into nothing more than a buzz word to sell products (I hate to seem anti-Canopus, but this is one of the many things they spamify on the box). The kind of audio drift that locked audio would prevent disappeared years ago. It died with the Pentium III and early-gen P4 Celerons. We're left with audio drift from other reasons.

[GrofLuigi]

Hi, I found this thread late and most of the things I would have wanted to say are already covered by other posters (and I agree with almost all of the responses), so I would like just to emphasize some points which I feel might be lost in the discussion, and (in my opinion and experience) are important:

1. As said, I would give up on USB capturing devices, since they mostly have poor quality and even worse A/V sync problems (usually).

2. The source of audio async is most likely the frequency drift of the audio cards' crystal oscilator, which varies slightly with time (48008 Hz, which I think it's just an average at the end, but it varies all the time). At the time I (and maybe others) were hunting for cards that didn't have this drift, but never could find one below the highest-end (most expensive) cards. But there's no need to, resampling audio is the way to go. No matter how much of a perfectionist one is (I am one too - up to a reasonable limit ), these few Hertz (or tens of, even hundreds of them) will never be noticeable. I am not sure how this drift is translated into the resulting audio when resampling, but I think it's not the frequency of the tone that's varied, but the sampling rate - you end up with few milliseconds of (very slightly) decreased "resolution" of your audio - so what? VHS is up to 10 KHz anyway (as far as I remember; just like SVHS's Hi-Fi audio track was 16 KHz).

3. Also, I suspect another capture card might not be needed at all. What I would do, first, is to determine the chip of the Pinnacle card and maybe hunt for a better driver (if it's BT8xx, it's no contest - BtWinCap is the way to go, maybe with Bt Tweaker).

4. If all else fails, I concur that the most pain-free solution would be to (buy)/(buy used)/(borrow from a friend)/(rent) a DV camera with pass-through (some of them don't have it). DV is way more than enough for VHS. I've heard both good and bad thing about Canopus cards and the like, and I suspect such a solution would be overkill. A DVD recorder might do the job too, but I personally would not use it because of limited re-editing and/or filtering possibilities. But again, it might be good enough for some uses, even with recompression.

5. If VirtualDub crashed on you, next time when you enter capture mode, hold SHIFT and it will not select a capture driver.

I had more thoughts, but I have to go now...

GL

[lordsmurf]

I'm not aware of any TBCs found in consumer VCRs. The higher-end decks from JVC, Panasonic and Mitsubishi may not be rack-mounted gear, but they are definitely professional and/or broadcast field equipment. The TBCs provide some functions, but not others. I wrote about this in a forum post here recently, and the more expanded information is at http://www.digitalfaq.com/forum/show...8710-1853.html (3rd post down). It can reduce dropped frames, but it won't remove/prevent them like a full external unit will. The 8710, for example, is $200 range, and uses standard composite/s-video connections. More on that TBC in the above linked thread (in fact, that thread initially started out as an AVT-8710 topic).

Good audio info.

[zilog jones]

Originally Posted by lordsmurf

I'm not aware of any TBCs found in consumer VCRs. The higher-end decks from JVC, Panasonic and Mitsubishi may not be rack-mounted gear, but they are definitely professional and/or broadcast field equipment.

This NV-HS960 has a lot of consumery functions though - tuner, VideoPlus, PDC, S-VHS ET, Tape Library, satellite receiver control, CC/teletext subtitles display, etc. (most of these are completely useless now ) JVC HR-S7000-9000 series VCRs seem similarly consumer-oriented. Maybe "prosumer" would be more appropriate as they have loads of edit functions too. I've seen JVC models that look like HR-S7600's etc. but have no consumer features (no tuner etc.), but forget the model numbers (BR something?).

I read your TBC discussion before, some very useful information there. You're pretty much on the mark with regards to S-VHS VCR line TBCs from my experience - it can increase jitter in some cases, but will improve chroma noise and straighten out a skewed picture. I've also noticed that somehow when the TBC and DNR are turned on it will produce a stable picture when cue/reviewing (no dropped frames when capturing) - an interesting, if not very useful feature...