Dropped frames only with VirtualDub?

[ElieFP]

I just bought a new PC to be able to capture old 8mm video tape with analogue video capture, a VIVO card and unfortunately, until now I couldn´t make a good SVCD.

The problem I have is Capturing. I have tried many capture programs and in spite that some of them doesn't indicate dropped frames, the average frame rate of each AVI file shows that there are a lot of dropped frames.

Capturing with Virtual Dub, I have from 15 to 45% dropped frames, no mother of the format, the compresion, etc. CPU usage is about 20%
There is something curious.
If I capture at 30 frames/sec I get an average frame rate of 25 frames/S
If I capture at 25 frames/sec I get an average frame rate of 16,66 fram/S
If I capture at 20 frames/sec I get an average frame rate of 16,66 fram/S
If I capture at 10 frames/sec I get an average frame rate of 8,32 fram/S
If I capture at 1 frame/Sec I get an average frame rate of 0,83 frames/S

Capturing with iuVCR there is no frames dropped but I have the same average frame rate that I see with VirtualDub

Capturing with ULEAD Video Studio 6, the same happens

So, I have to understand that there are always dropped frames and I don't know what to do.

I have followed many advices from the guides but without success. The next one will be to load a new OS, Windows 2K and try.

Is there any boby that had the same problem and found a solution?

Thanks a lot for the work that every body does at VCDHelp. Really, to affort this kind of problem without help is very difficult.

Sorry for my poor English

Regards

ElieFP

[JamieWWE]

YOU DROP FRAMES WITH 1FPS?????????????? How slow is your computer? Tell us your stats and cpu. It looks like you need to buy more ram, about 256 is satisfactury. What res do u use? 352 x 288? Do u capture at DVD res? Turn the res down. Use Picvideo codec.

[metebelis]

I had this problem when i first started capping and my solution was to enable DMA transfer for my hard drives on the IDE channel. For some reason on my machine the default transfer mode was PIO. I changed it to DMA and no more dropped frames. Hope this helps....

[ElieFP]

Answer to Jammie WWE
You can see my computer specifications on the upper right side menu.

It is a new computer with AMD Atllon 1800+

Answer to Metebelis

The DMA is OK - HDD are ATA100.

The same problem happens with very low resolution. It is not the problem

Thanks for the reply

[ElieFP]

Answer to Jammie WWE
You can see my computer specifications on the upper right side menu.

It is a new computer with AMD Atllon 1800+

Answer to Metebelis

The DMA is OK - HDD are ATA100.

The same problem happens with very low resolution. It is not the problem

Thanks for the reply

[ChRaN]

when capturing i VirtualDub use overlay and not preview

[alkieman]

Elie, there are several reasons why your computer may be having problems, try the following:

Enable DMA on your hard disc.

Start with 256Mb ram, 128 is OK at a push but the more memory the better.

Disable your virus checking software if it is running in the background.

Exit all unnecessary programs that run at startup, essentially you want to have no other programs running at all.

Use a suitable codec. Capturing to native uncompressed AVI requires an incredibly powerful computer and takes up massive amounts of disk space. Even ATA133 is not fast enough for full resolution, uncompressed AVI capture. If you are using one of the native codecs included with Windows you wont be able to get decent capture performance.

There are probably three good codecs that are available reasonably priced that most people use.

MJPEG is pretty good for capture and my setup works fine with a quality setting of 18 (highest is 20 under the PicVideo MJPEG codec). I have an AMD Athlon 133, 512Mb ram and an ATA133, 7200RPM hard disk (recently installed a couple of RAID drives and improved performance a bit) and I can happily capture fullscreen PAL 720x576, 24bit RGB AVI files. Cost is about 20USD from MainConcept.

A DV codec is also available stand alone from MainConcept and their one works whether or not you have a DV cam. Again, I have no problems capturing full PAL at 24bit colour. Cost is about 50 USD

You could also try the HUFFYUV codec which works pretty well too, but this can cause problems with some editing software. It is however, free and worthy a try.

In Virtualdub use OVERLAY and not PREVIEW as ChRan says. Increase the number of video buffers to a higher number, 10 or 12 works well. Also try reducing the colour resolution to 15bit RGB if 24bit still has problems, you'll not notice the difference in playback of the captured files.

Hope that lot helps improve things.

[Digitizer]

In VirtualDub it seams more like round-off math errors. If you switch from 30 fps to 29.97 fps, the dropped frames ratio should decrease by much.

[pijetro]

Just out of curiosity, what resolution are you capturing at, and are you capturing with PCM wave audio?

[RoopeT]

And what is your sound card model? Maybe the dropped frames are adio/video synch related. Try to get new drivers for your sound card, check the recording properties from controlpanel, and try using a special version of VirtualDub, Virtual Dub synch (http://www-user.rhrk.uni-kl.de/~dittrich/sync/)

[calamari]

Wow, that's cool! I can't wait to try VirtualDub sync out, I bet it fixes all my syncing problems

Thanks for the link,
calamari

[ElieFP]

Answer for:
ChRan --> I have to try it. thanks
Alkieman --> Hard disk is DMA mode
I have 256 MB RAM
No anti virus working
Closed every program that are not needed
I Capture with HUFFYUV codec
I don`t use preview (hide on capture)
I have to try to increase the number ogf buffers. Thanks
Roopet --> The maindboard has buit in audio desabled
I use a sound blaster 128 audio card
Thanks
Pijetro --> The problem of frames dropped is with any resolution.
I have tried a very low one with the same result
Thanks
Digitizer --> As you can see on the above information, dropped frames follow a strange rule. Whwn I decrease the frame rate slowly, the average captured frames drops from 25 to 16,6 and it stay in this value until I reduce the capture frame rate uner 18 frames/sec. Than, the average dropped frames fall until the next step that is maybe 12 frames/Sec. Next step will be install a new OS - W2K
Thanks