Dropped Frames in VirtualDub

[andy73au]

Hi, can anyone tell me why I am getting heaps of dropped frames when capturing with VirtualDub?

I'm capturing at 640 x 480 with Divx 5.02. My CPU is a P4 2.4GHZ and am capturing with a Leadtek Ti4200 64mb card.

I am also trying to capture at 25 fps.

Any help would be much appreciated....

thanks
Andrew

[Poplar]

Well, your computer isn't fast enough to capture to DivX in real-time. There had been reports that some guy succeeded in doing real-time DivX capture. Don't know what kind of machine he had or what resolution he was capturing with. Guess you have to cap to Huffy or uncompressed, then do the DivX conversion.

[crahak]

DivX isn't a capture codec anyways. You want something like a mjpeg codec, or huffyuv...

[andy73au]

I tried capturing with NO compression and I'm still getting loads of dropped frames and the average frame rate is around 16-17 FPS. What the hell is going on here?....Why the hell did I fork out for a fast CPU when I cant even capture at 25 fps with no dropped frames.....This happens at both 640 x 480 and 352 x 288 resolutions. I then install the Huffyuv codec and STILL no joy......heaps of dropped frames....

Any clues???? Someone out there must know whats going on.

P.S. I'm capturing with a Leadtek Winfast MyVivo Geforce4 Ti4200 64mb.

[Nelson37]

If you have dropped the resolution AND used Huffy and are still dropping frames, on that machine, something is wrong.

Are you capturing to your OS boot drive? OS performs periodic traffic to boot drive, need second drive for cap. Search for Dropped Frames, many posts on this.

Also standard is eliminate ALL other running programs.

DivX not intended for capture, but several report using it.

NO compression gives a file so big you may be exceeding throughput limits on drive, DivX tend to overload processor. Huffy and lower res should cap with NO drops, Huffy and 720x480 I get about 1 drop per 10 minutes on an Athlon 1700 with a 60gig cap drive.

[jeremypps]

andy, your cpu IS fast enough to do divx capturing on the fly.
are you trying to compress audio as well? this could be a problem.
others: disk not well defragmented, problems in a/v sync, source signal with lot of noise and others.
sorry i can't help much, but keep trying, somebody here will probably do better.
good luck, jeremy.

[hardwork12]

andy73au

What are you trying to capture? (ex: 8mm, TV broadcasts, VHS etc). One reason I ask is that you state that you are trying to capture at 25 FPS but if you source is NTSC that is 29.97. I did a test and if I try to capture a 29.97 source with virtualdub at a setting of 25 I get dropped frames since the source is faster than the capture (at least that is my theory). I calculated 29.97/25 0r 20% dropped frames if this was the cause and I got 18% dropped frames for a 30 min capture. I then dropped the FPS capture to 15 and got 50% dropped frames. Set it to 29.97 and got 0 dropped frames. Just a thought.

When you say Dropped frames what % dropped?

This might help understand the issue/cause.

Just as a point of reference my 900mhz using huffyuv compression or no compression at all I can capture with zero frame loss at 640x480 so I know your system is fast enough.

[andy73au]

Yeah I'm trying to capture from VHS......just music videos......The source is PAL so that is why I have set to 25fps....I have tried Huffy, divx and uncompressed and still get heaps of dropped frames......

You would think with a CPU this fast there would be no dropped frames but as soon I clcik capture they start racing.....(i.e. for a 4 minute music vid.....there are over 1300 dropped frames or even more.......)

I'm just a newbie at all this capturing so bear with me.........

Andy

[hardwork12]

I have only been at this for about 6 weeks now but have been tweaking and building AMD systems for years. NVIDIA products are my favorite for games. I do not have a geforce 4 videocard but I can offer some possibilities for tweaking the computer maybe they will help.

Just something to think about getting. In order to tweak your system with driver changes and stuff you run a big risk of causing a fatal failure of the operating system. I would get a copy of Nortons/symantec GHOST and CD back-up you operating system. This way you can restore back to pre-changes very quickly. I had to do this multiple times while playing with different drivers. To me this is a must. Just a recommendation.

I have tested my system with 8mmand VHS and both give me some dropped frames but VHS is quite good I get less than 0.1% dropped. One thing I used to debug my hardware when I was getting dropped frames in the 2% range was to hook up my DVD player this source should be able to be captured with no dropped frames (well maybe 1 or 2). I would use your DVD player to help you debug this problem and also rule out if the problem is the VCR player (some have poor v_sync I think it is called and that can cause dropped frames and even worse with 8mm).

If you have not installed the latest drivers then I would do that. For Leadtek (I own a geforce 2 and 3) which uses the NVIDIA reference design I always install the latest generic drivers from NVIDIA not the latest Leadtek. I go here and install the latest Detonator drivers.

http://www.nvidia.com/view.asp?IO=winxp-2k_41.09

The 256 meg ram should be enough I did some tests and capture is CPU intensive but not RAM intensive just make sure you do not have any other applications running and especially do not leave any internet browser windows open (these are memory hogs).

Some settings in your BIOS to concider. These changes will not noticeably slow your system but do lend more stability:

Set the AGP aperature size to 128meg (1/2 your RAM)
Turn off all memory cache especially video cache.

Maybe the problem is the source not the capture. Hope some of this helps.

[kryten]

Is the source tape something you taped off TV? Or a tape you bought?

If it's a store bought tape, copy protection could be an issue. I've tried capturing some of my store bought tapes, and every couple seconds it will drop a ton of frames because it can't deal with the protection. The only solution I found was to get a "Video Enhancer" to place between the VCR and capture card which strips the original sync signal off the video, and generates a new sync signal.

If it's something you taped yourself, then I'm at a loss.

P.S. You did turn anti-virus software off before starting the capture, right?

----------------------------
your humble mechanoid,
Kryten

[SCM]

Ok, I don´t know if Gf4 are WDM drivers, if not, all this would be useless.


If GF4 uses Wdm drivers, try to use virtualVCR to capture the video (you can find it on this site, under tools section), and then use virtualdub to do any other editing you wish to do.

I can capture with VirtualVCR using divx5.02 codec, compression set to SVCD standard. with 0 framedrops, it I use VirtualDub, I get close to 1 frame drop every minute or so, using the same settings

Also with VirtualVCR you could take down the prof if your framedrop is due hardware issues or is a lack of sincronism with video (it have 2 framedrops statistics, the first is due hardware limitation, the second, is due lack of sincronism with the signal and the capture video signal.


Hope that helps

[Nelson37]

Try different source type - cable, satelite, DVD. VHS often source of frame drop, SIMA copymaster may help. Different tape or Different player may solve problem.

[andy73au]

The tape I'm trying to capture off is a something I taped off TV......VirtualDub is currenty dropping 34% of frames........

Do the latest Detenator drivers have the latest capture drivers?????

Like I said above, I've tried divx, uncompressed and Huffyuv and still dropped frames.

My system try contains Norton Antivirys, Norton Firewall, Fix-it Utilities, Po-up Killer, IncreMail email program..........maybe having all this shit in the sys tray is killing it........any thoughts.........

I'll try a few more things and see what happens....

Thanks for all the responses.....

I'm starting to think its the card........I don't think I should have a bought a card with video in and instead bought a third party card...like Pinnacle or Hauppage.........F@#@k.!!!!!!!!!!

OUT..

[SCM]

Man, disable ALL TSR programs, especially Norton programs, (Antivirus software/ disktool softwares monitor all disk access, degragin greatlly your performance.

It doesn´t matter how fast your system is, if you maintain Anti virus software enables, be prepared for tons and tons of framedrops...

Wich OS are you running, thera are several ways of disable such services, but it depends on your operational system.


(win98/me use msconfig, Win2kpro use task manager etc)

You can find a tutorial about this performance in win98/me under howto capture, search for how to capture using radeon cards, your card is diferent, but the first part of the document is based on general performance tips.)

[andy73au]

Running....WinXP Pro......

Yeah I happen to agree that these programs are killing the capture quality.....

Will disable all and try to capture to see if the dropped frames occur.............

[andy73au]

OK, I have now disabled and or unistalled everything......that is all Norton programs and any web programs etc.......

I even updated my video card to the latest drivers.........

When I go to capture in VirtualDub.........I'm still getting heaps of dropped frames...........

I'm now really pissed off.....!!!!!!!!!!!!!!!!!!!!!!

What is going on here...

Extremely frustrated.................

I think I'm going to format C:\