VirtualDub massive frame loss at some moments

[Muiter]

When I'm capturing (not from a brand new tape) in VirtualDub suddenly the video stalls (the sound is perfect) and I lose a lot of frames (about 10 frames a second) at some (not all) moments. When I'm only watching the tape in VirtualDub the image is perfect.
It has nothing to do with other programs or my computer speed.

Does anyone know a solution for this problem?

Thanks in advance

[BJ_M]

maybe your hard drive is doing something else .. if you are capturing on a hard drive you use for something else ... you didnt leave a lot of info about your system so hard to tell..

[Greg12]

Try these things

1.) Make sure your screensaver is disabled.
2.) Make sure your not online, unplug network if needed.
3.) close as many programs as you can. You should only have essiential programs running in the background.

[Muiter]

I received an e-mail from a friend:

It is our joint trouble. I made the analysis of this problem. I shall tell about the conclusions, but to decide this problem is difficultly.

See the picture. It is three oscillograms of videosignal.

Number 1 is normal signal from videocamera. You can see rectangular impulse of sincro (S) and almost square package of chroma signals (C).

And now number 2. It is the same signal after recording/playback with videorecorder. Synchronization has become oval instead of rectangular. The chroma too has changed. But it is normally. Such signals are well determined by a capture card.

And the extremal case, number 3. The tape segment is not enough well. The synchronization has become absolutely small. The chroma too. The outcome will be such: the capture card will not see such small signal and will not start capture of this frame. The frame will be lost.

If I could make a signal amplifier... But the amplifier, boosts which one only a sinchro-signal. The amplifier, which one will not change amplitude of a video, and will increase only synchronization. Then the problem would be resolved. I had the friend, which one promised to make such amplifier. But the friend has left also I have not communication with him. I know, that there are videotape recorders, which one have an amplitude control of procedure signals. But it is professional engineering, which one is unavailable to us.

Best regards,

I hope anyone can help me now.

[BJ_M]

what he is saying is get a new vcr ... but i havnt run across this problem myself ever ... if you can see it - watching it in v-dub .. i think you should be able to capture it ..

[Muiter]

I have tried 2 VCR's and I it doesn't make any difference
When I'm playing the video using VD there is no problem but I do when I start capturing.

[marscable]

If ur using WinME or WinXp try to disable the "System Restore"(stupid feature).. see if it helps.. :^)

[Muiter]

If ur using WinME or WinXp try to disable the "System Restore"(stupid feature).. see if it helps.. :^)

Doesn't make any difference

[spidey]

You have disabled all unnecessary services prior to beginning the capture ?? Most hhave already been mentioned, but make sure the only active apps are the base Windows applications, and the capturing.

Including:

AntiVirus
Screensavers
Sleep Mode or any powersaving on the hard drives

This could be your culprit, in hearing how it is in regular intervals. Adjust under your Power Saving scemes to NEVER sleep. Depending on your drives there may also be BIOS features to address.

Before Capping boot up your Task manager and make sure anything that is unnecessary is shut off

[Muiter]

Yes I have only VirtualDub running when I'm capturing. I have said before I don't have this problem when I'm capturing a normal TV signal. I have this problem only when I capture from a videotape.

[Muiter]

I want to try another capture program instaed of VirtualDub. What is a good one to try that has the same options (.avi) as VirtualDub?

[BJ_M]

i like AVI_IO

[vhelp]

afternoon muiter,

How about... what is the source material LIKE???

* age of tape
* vcr you taped it to (your current vcr or someone elses)
* mode you tape to ie, SP (best) EP (poorer, well, for beginners anyways)
* originated source, ie attenna or cable or satalite, other etc.
* then, quality of the above source... from attenna, cable or satalite, other etc.
* or, in short, who/what/when/where was the tape recorded?

Also,
* what is your sound card make/model ??
note, don't use your motherboards build-in one, as I have, and cause timing issues
for most of my caps.
I replaced w/ an OLD Vortex SQ1500 sound card, and some drops WERE reduced,
but I had other issues to clear up as well. (see Other Issues below)

Note 1:
* Did you try a store bought movie, to see if you get same drops in frames?
But, even these will cause drops in frames, weather in intervals or not.
Note 2:
* Sometimes, even though you get no (or very little) frame drops in other capture
scenarios, ie TV captures... these are easier on the capture-to-framedrop ratio, while
you VCR is another or more sensitive device and is therefore less forgiving, hence
your framedrops.
Note 3:
* it would be advisable to Image your setup, once you get your framedrops
issue settled. So that in case you make a change or add a new hardware, if
things should go wrong, you can revert back to your old setup w/out forgetful
steps and headackes.
Note 4:
* is really a recommendatoin - get a WTVGO card, at least in my experience, this card,
when properly setup (below) will give you ZERO frame drops at 352x480. I haven't
quite tested 720x480, but I would suspect it could handle it w/ZERO frame drops.
I have the following cards: ATW; ATWVE; ATIRFP; DC10; PCPVR (and others) and
these all drop frames (random numbers for each) but the WTVGO card holds its
ground. I would suspect that as for the drops w/ other cards, it's due to a
driver and motherboard timing issue or something of that nature.

Other issues:
* Clean Driver/Direct-X/Graph Card installation
there is an order to follow, and
* Proper HD setup
ie, a good setup would be,
-- drive c: your boot windows drive
...on PRIMARY CONNECTOR (blue cables)
-- drive d: your capture drive
...on SECONDARY CONNECTOR (blue cables)
ie, a good setup would (an alternate one) be,
-- drive c: your boot windows drive
...on PRIMARY CONNECTOR (blue cables)
-- drive d: your capture drive
...on PRIMARY CONNECTOR (same blue cables)
-- drive e and f would be your DVD-ROM and then your CD-RW drive
...on SECONDARY CONNECTOR (same blue cables)

As always, DEFRAG your captured DRIVE.
Here is a great tip from VHELP's experience. . .
* assuming your capture drive is separate (recommended) it is best NOT for reformat
it as is advised here elsewheres. Instead, ALWAYS keep a tiny file laying around
in your capture's drives' root directory ie D:\01.vdr is a good one I use.
THEN, run a defrag on it. Two things is happening here:
1, it will take very little time, ie on mine, it take 7 seconds to defrag.
2, you are assuring yourself a more PERFECT defrag and your point-of-origion will be
at the optimum placement on your HD, ie, it will be at beginning. Else, if you don't
your fragmentation (start of captured files) will begin anywheres on the HD, ie like
in the center or near the end, etc, being left w/ no order. If you follow my advice
you'll always have files starting at the beggining, 1, 2, 3, 4, 5, vs. maybe in the
center 8, 20, 7, 3, 4, 100, 121, 18, 19. ...Why this pattern, instead of 1,2,3,4,5...??
because there were no files on the HD to use as a reference, and so, these areas
were not CLEARED. So, the next time a file is written, it see's these open areas, ie
8, 20, 7 etc. and places these files there. Though files aren't fragmented in them
selves, the placements are! So, the time it takes for the nidle to bounce back and
forth IMO, is enough to cause some frame drops or help cause some.
If you don't defrag in this mannor, and instead, defrag w/out ANY file, you'll suffer
the above's 8, 20, 7, 3, 4, 100, 121, 18, 19 defrag layout. You can verify this
with Nortons Disk map, if you can set it up in a test like. Anyways...
I hope you all understand what I'm trying to point out here.

The key to a successful process (no frame drops) is the above!!

Sorry if I was a bit anal above, he, he...

Oh, and AVI_IO is a good capture app. This is the one I use w/ ZERO frame
drops. However, I do use VDUB, when I'm not doing long captures, 1 drop in 5
minutes or ZERO is ok in some projects. But, AVI_VIO, when I want ZERO! But,
currently, I'm using both my WTVGO and DC10 cards. The DC10 is the best card for
VHS sources if they are STORE bought movies only. Unfortunately, as w/ VHS
sources, you can't get rid of the Jigglies (shimmer effect) on some VHS sources,
but I have experimented w/ my Canon ZR10 DV cam on some, (those that DO escape
macrovision) and when I capture from the DV cam, via analog (DC10+ or WTVGO) the
Jiggleies or Shimmers are almost gone. So, something does happen in this process.
But, the tradeoff is the color quality is reduced, and some noise is ADDed. So,
its a win/loose situation here.

-vhelp

[Muiter]

I used to capture without any problems with the same hardware and settings maybe it's a VCR problem after all

OR:

When I record a videotape I can capture it with no problems. But when try to capture a tape I have already watched 1 time I start to have those problems When I try a new tape from a store I don't have problems with the first time capture. When I try it to capture again I start to have problems.

AND:

When I capture from my TV-signal trough my VCR I have also no problems.

i like AVI_IO

I tried that one and I have the same problem. Also the same problems with Adobe Premiere 6.0

[Muiter]

Today I tried a new TV-card and a new VCR and I still have the same problems. Are there any more ideas????

[vhelp]

evening everyone.

Muiter,
I'm gonna assume that, by your going out and buying an NEW card, you were
refering to yet another PCTV card, right? ?

Ok, assuming that you bought another PCTV card. Then Maybe the PCTV suffers
the SAME symtoms as the DC10+ cards do. . .that when the source is from a VCR
(vhs) no matter how fast your CPU is and NO IRQs and HD at best super-doopper
settings, you will have frame drops! But other sources like Sat and DVD
there are NONE! At least, w/ my DC10+ and ALL other sources, I get NO frame
drops. It's only when I start capping from my VCR and any type source, be it
from a recording off my satalite or DVD player, or even store bought movies.
I'll have frame drops.
So, in the above case, your PCTV card is to blame for your VCR frame drops.
I do know that my WTVGO card drop NO frame, and even at 720x480 (as I have
recently found out through a number of tests) - - at 720x480 even!!
So, then, why don't I use my WTVGO card for capturig from my VCR? ? well, it's
because of the Line Noise I seem to suffer from. But, with my DC10+
card, I have NO noise what-so-ever, and that's pretty much why! But, I'm
still experimenting on some capture testings w/ my WTVGO and VCR sources.
Anyways. . . I was doing so more experimenting, and now I do have a NEW sample
that I posted (link below) to if you want to see how it looks. It's pretty darn
good, for a VHS capture though, don't you think? Well, D/L it and check it out
anyways.

I think though, that all capture cards form Pinicle suffer from this same
issue w/ VCR sources. I believe that someone, the, in my case, DC10+ locks
into the sync or video frame or whatever/however they word it, andways... and
when a bad frame is encountered, it drops 1 or 2 or 3 or 5 or whatever as it
encounters them.

On the other hand, I just don't get it, when you say that your 1st time vhs
captures have no frame drops, but succeeding one from this same vhs tape will
cause frame drops! I don't understand that one though.

ok, i'm of to anwere another post, he, he...

-vhelp
----------------------------------------------
For Standard and other VCD samples, you can jump over to this FORUM's link
here: VHELP's Samples... - last updated: 09.24.02

[Thorn]

Changing the video buffers helped me eliminate some dropped frames. I assume your drive is fast enough if you can capture other stuff.

So to narrow this down, if you can capture ok from other VHS tapes on the same VCR, then the tape is the problem. Even if you don't see it, there could be noise that kills virtualdub or the codec. I've seen massive framedrops (as in it almost stops capturing after the event) when I stop the vcr tape... I don't know exactly what causes that but I think the noise is way to large for huffy to handle when it tries to compress. Try capturing in other codecs and most importantly try capturing raw with no codec. If the computer isn't trying to compress the data, it may not crap out.

Other than that maybe it's a strange signal spike. Perhaps send the signal through another device? Or maybe just use a different VCR altogether.

[BJ_M]

make sure they are both plugged into the same electrical outlet ..

[Muiter]

Thanks for all the replys!!!

I'm gonna assume that, by your going out and buying an NEW card, you were
refering to yet another PCTV card, right? ?

that I posted (link below) to if you want to see how it looks. It's pretty darn
good, for a VHS capture though, don't you think? Well, D/L it and check it out

On the other hand, I just don't get it, when you say that your 1st time vhs
captures have no frame drops, but succeeding one from this same vhs tape will
cause frame drops! I don't understand that one though.

I was refering to another PCTV card (Rave).

The quality in the sample video is great!

And I used to capture (with the same settings) as always
http://www.farzadsf1gallery.com/phpBB2/viewtopic.php?t=2088

Changing the video buffers helped me eliminate some dropped frames.

if you can capture ok from other VHS tapes on the same VCR, then the tape is the problem.

Try capturing in other codecs and most importantly try capturing raw with no codec. If the computer isn't trying to compress the data, it may not crap out.

Other than that maybe it's a strange signal spike. Perhaps send the signal through another device? Or maybe just use a different VCR altogether.

How can I change the video buffers?

I can't, I have problems with all my video tapes.

I have tryd to capture with other settings/codecs and without any compression.

I have tried a brand new VCR, I also have tried Composite/S-Video/COAX

make sure they are both plugged into the same electrical outlet ..

They are

[Muiter]

I just found some old software for my TV-card. After I installed it I was able to capture with smaller problems then before. I'm almost sure now that it's a driver problem. Does anybody some other good drivers form my PCTV Pro card?

[Thorn]

Yea, driver problems are common... I don't know anything about your card though.

Some other info while you look for better drivers:

There are wrappers to allow you to use directshow drivers in virtualdub (used on ATI a lot).

Changing the resolution can make big differences. I assume you've tried small (such as 320x240) and large (such as 720x480) and compared the difference. Some people can't capture higher resolution because the new drivers they got suck (don't understand what the developers are thinking sometimes... no quality control).

To change video buffers: go to capture menu then diskIO. A larger chunk or more chunks per buffer seemed to help me - larger writes, less often might prevent a microsecond lag in getting to the HD from causing the a buffer to overflow and data to be dropped. I don't know the best settings. I think 'disable windows write buffering' is necessary otherwise windows buffers the data until it decides to write
Then go to capture/settings and look at the max video buffers. Can't reccomend any solid values there either but play with it... and remember nothing is saved unless you go into preferences and save current configuration.