Hi, bit of a newbie question sorry.
I'm doing DV capture and I get "some" dropped frames, not a huge amount but enough to ruin some scenes. I'm capturing using Studio 8 from my Panny GS-120 cam. When I watch the capture closely I see it momentarily freezes like my system is interupting it, the capture preview freezes for a second and the dropped frame count goes up. My PC is pretty well spec'd (maybe too much so... read on..).
My real question is, what are the main causes of dropped frames? I'm guessing it's my OS or some other resident app? Anti Virus is off.
However, I've just read some other threads suggesting RAID 0 is overkill and can cause some problems. I have SATA RAID 0 and having just had my first episode of losing my RAID volume am considering dumping it!
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Are all backgorund ops OFF? You may want to watch the CPU usage and or Task Manager to see what's kicking in at that very instance. Is it regular or ramdom?
My machine is onle a P$ 2400 megahurtz with a gig ram and regular IDE drives and I get zero dropped frames on studio 9.4 Plus
Trasfering from dv to dvd is just copying and nothing is encoding so you should be stressing anything out. As long as your drive can write the data as fast as it is being fed to the PC. Analog to DV is more resopurce intensive and that's when most people have probelms with dropped frames.No DVD can withstand the power of DVDShrink along with AnyDVD!
Originally Posted by jtoolman2000
Analog to dv is usually done with an external convertor (camcorder with passthrough, canopus advc units, ads tech pyro a/v link, etc...). So it would be like a DV-to-DV transfer by the time it's encoded by the external convertor.
What format are you capturing? mpeg-1 or mpeg-2, dv .avi, other???George
Yes, I've used WinDV. It "seems" a little better but not entirely. Maybe just my favourable opinion by chance of what I was doing. Have only done limited capturing at this stage.
The capture is DV to AVI.
The interuption does seem relatively regular. I'll follow the line of checking other resident apps and monitoring CPU.
Thanks for the help.
Just wondering, is the freeze always at the same point in the tape? If you have any timecode breaks in the tape, that can cause problems with capture. I don't have a raid setup, but defragging seems to help on my system when "capturing" DV."Just another sheep boy, duck call, swan
song, idiot son of donkey kong - Julian Cope"
I'm not really getting this: How can DV "capture" drop frames? AFAIK, it's just a matter of transferring binary data from one device (the camera) to another (the computer), no frames are neither decoded nor encoded during the process, if I understand anything about this. To me, this sounds as if I'd start dropping frames if I did a "copy c:\movie.avi d:\movie.avi"
There's a slight difference from going between two hard drives, and going from camcorder to hard drive. If the computer/hard drive cannot keep up (older HD's, or DMA not enabled, or computer busy doing other tasks, etc...), the camcorder keeps playing, but the writing of the dv stream is interrupted, and so you get dropped frames.
WinDV and other dv tools have a small "buffer" (afaik) that allows for these slight hiccups. So they can sometimes prevent dropped frames.
It's along the same lines as writing a CD-R or DVD disc, and the whole idea of "buffer underrun" protection. You want a steady/continous stream sent to the optical drive, otherwise the disc is useless.
Try turning DMA off on your capture HD, and open up a couple of programs during a dv transfer, and you could start to see dropped frames...George
I C! So, it's not "frame drop", as much as "data drop". Makes more sense.
I was transferring some home video from Digital Tape (D8) using DVIO and found that at a particular point DVIO would indicate Dropped Frames. The tape played OK in the camera over that area.
I then tried WinDV and it transferred that area without any problem...
So try downloading a few different DV transfer apps and see if one works.
OK, it's coming together a bit now.
I was capturing using WinDV and noticed the same intermittent freeze in the capture preview HOWEVER the resulting AVI was fine. So WinDV's buffering abilities must have dealt with it. Studio 8 however doesn't seem to. By chance does anyone know if Studio 9 or another integrated editing app does a better job at this?
I think I'll just use WinDV for all my capture.
I'll still follow up why my system is giving me the interupt problem anyway as I can't see why it would be a simple data transfer rate issue. My data drives are new 200GB SATA in RAID 0. I'm using the intel RAID controller, not the onboard Promise controller. And I have a seperate dedicated system drive. I spent some reasonable $ to try an avoid these problems.
Is it sensible to setup a XP login that loads no TSR's?
Oh, actually one more thought... my ASUS board has a diagnostic app that runs in the background, perhaps that could be it.
Appreciate the help. DV is a big wide world!!! How many years before I'll be the "helper"??
DV transfer is actually all about sustained data rate. In saying that, the required rate is very slow at around 3.8MB per second. If you have Nero installed, open up Nero, go to Preferences, Cache and you will see a button marked 'Test All Drive Speeds'. This will test the sustained data transfer rate for all your drives. I've just checked mine and found 38MB per second for my FAT32 boot drive, 47MB per second for an NTFS partition on the same physical drive and 48MB per second for my NTFS capture drive. This is on UDMA 133 drives with DMA enabled. Don't be fooled by the 133MB per second that this implies, that is the maximum burst rate and not a continuous figure.
Unless you have results very similar to these figures, you have something seriously holding up the transfer rate which is causing the dropped frames.
Originally Posted by spurs61
Are you capturing to a single drive? What is your system spec?
I'll check my drive speed speed with Nero as suggested.
I've got an ASUS P4C800-E Deluxe m/board. My system drive is a 160GB UDMA drive. I capture to my RAID 0 volume which is 2 x 400GB Serial ATA drives. In investigating this problem I've read some other threads here saying RAID is overkill for DV capture and can cause problems. I configured the RAID using the intel controller as I read the on board promise controller can cause performance problems based on where it sits on the MB.
Like Richard_G says, the required data rate for DV is quite low and so I'd be really surprised if I have a disk problem here, but I'm learning to be prepared for anything in the DV world!
I'm prepared to attack this methodically to find the problem, My plan of attack is
a) Benchmark my drive performance to see if there's an obvious problem there.
b) Repeat the capture the video I last did with Studio 8 and see if I have the same problem and in the same places
c) Capture the video I last did with WinDV and see how that compares
d) IF I'm still having problems, try b) and c) again but with TSR's all terminated.
e) IF I'm still having problems, try b) and c) again but capture to my single system drive (theoretically should be worse if anything??).
f) IF I'm still having problems, god help me, I may scrap my RAID volume and move to two single drives and see how that goes...
Feel free to tell me my plan of attack is crazy
Originally Posted by spurs61
No solution has been reported other than replacing motherboard RAID with a dedicated SATA controller (non-RAID) channel or a SATA RAID card.
This is not a problem with EIDE based motherboard RAID 0. I have two running (Gigabyte-Promise on board RAID and FastTrak RAID card.)
My opininion is RAID is not needed at all for a single stream DV transfer (ATA66 or better). A single modern drive (and ATA100 or better controller) will perform more than adequately.
I do reccommend a separate capture drive and disk controller from the OS drive-controller. (see my many other posts).
I checked my drive speeds with nero as suggested by Richard_G. My system drive was ~55MB/sec and my RAID 0 volume was ~80MB/sec, so no problem there.
I've now captured about 15 mins of video using WinDV and no dropped frames
I then repeated the exact same capture using Studio 8 and got ~70 dropped frames
So on the surface of it it seems to be the capture app that is the problem. But really it's probably simply that WinDV utilises a buffer so is tolerant to some hiccups in throughput. App aside the "hiccup" is still there! My drives appear to easily have a sufficent transfer rate but the "hiccup" must cause the transfer rate to momentarily drop to a level where I lose a few fames. So from here I think I'll use WinDV for all my capturing from now on AND follow up on the hiccup issue some more later. The more I read the more I hear onboard SATA RAID 0 can cuase some problems, as mentioned by edDV here. I might follow up on some TSR's first. Interestingly I tried to "hit" my data volume while capturing by browsing it and opening some other files to make it drop frames... and it didn't.
I'll post any findings.
Thanks heaps for all the help... learning lots!
For what its worth, I rountinely cap 2-3hr movies and 6hr VHS tapes over a IEEE-1394 DV connection with no dropped frames and without RAID. I do this with several drives on various computers. You should not be dropping frames.
The capture apps have little to do. They just make calls on Direct X (Direct Show) for IEEE-1394 transfer. No rocket science there. Your problems are probably due to either background processes or RAID driver issues.
From my experiences with Firewire dropped frames, I found the problem to be the capture app.
DVIO simply would not capture a particular 4 minute segement of a tape, yet WinDV and several other freware apps I had did capture those 4 minutes without error.
This would lead me to think that the data stream had something that DVIO could not handle, possibly because of a bug in the app, while the other Apps could handle it. Another possibility could be a problem on the source tape that DVIO could not correct while other apps could. Either way, the capture app did make a difference, at least in my case.
To further confirm this, I tried to capture on a different machine and guess what? DVIO dropped frames, WinDV did not. The two different machines where a P4 2.4Ghz, with a single 40GB drive, and a PII 333MHz capturing to a separate 60 GB Drive. (I routinely capture with the old PII without dropped frames)
Try and determine where the dropped frames happen. If there are some background processes causing the problem you'd expect the dropped frames to be more random, and at different times when recapturing from the same tape. If they always happen at the same place I'd think it has more to do with the capture app.
Thanks, I'll follow this up.
As a side issue I use my DV Cam's passthrough capabilities to capture from analogue devices. With this setup I assume I am still technically doing DV capture and all the theories should still hold (as the analogue to digital conversion is taking place outside my system and I am just capturing a DV stream)?
I just don't want to start tweaking my system for DV capture alone if my method of analogue capture will suffer as a result.
Yes, the computer just sees a DV stream.
I suggest you isolate issues.
1. Try to cap to your OS drive and see you have the same issues there. If not, I would suspect the RAID drivers.
Note. It's not normally good practice to capture to the OS drive since the OS may take control of the drive at its whim causing stream drops. I suggest the above just as a test.
2. Try the various capture apps (including Windows Movie Maker 2 in DV capture mode). See if the problem differs by app. WinDV is the simplest design.
I would still suggest dumping the RAID in favor of single SATA channels and see if that does better. I don't see where you would benefit from RAID.
I had the same problem with Video Studio 8 and laptop hard drive, I use Windv instead and had no problems with dropped data. I also use a seperate external hard drive for footage too and have no probs. I shall have to try VS8 capture again but using the external drive to see if this makes any difference. I find VS8 unpredictably buggy.Why is it doing that?
VS8 works fine on my multi HDD desktops. Notebooks can be very problematic for reasons much discussed (e.g. single drives, OS contention, power modes, etc.).
Results of capturing in VS8:
I've been converting VHS to DVD the last few weeks. VCR thru Canon 750i thru firewire to external HDD using AVI in Windv. Works great but time consuming transposing down to MPEG. Tonight I thought I'd try VS8 to capture with MPEG at 4500kbps. Looked good until the damn program decided to stop capturing all by itself at 20 mins the first try and 9 mins the second time. As I said above, VS8 is unpredictably buggy. The footage I did get was good quality though, which makes it more of a shame. So its back to good old AVI in Windv for me.Why is it doing that?
I suspect the problem lies in your background tasks, OS power settings, antivirus etc. If your laptop is FAT32, you will hit the 2GB or 4GB wall on maximum file size. It could be other things not related to VS8. I routinely capture 6hr VHS tapes with VS8 (Celeron 2.4 desktop, 512MB RAM, XP, NTFS, separate capture drives).
Short of fixing the problem, just capture in segments and join them in post processing.
PS the Celeron 2.4GHz can handle realtime MPeg2 encoding @ 7,000Kb/s VBR, LPCM audio using VS8's Mainconcept encoder DVD defaults.
OK, I've finished my tests and here are the results (and assumptions).
The dropped frames were not at the same place in any given capture but I clocked it dropping frames every 3 minutes on the dot. In fact it dropped ~70 frames every 3 minutes (70, 142, 217... exactly the same every time). BTW, it was Pinnacle Studio 8 I was using. Now WinDV doesn't have this problem but i think it's simply because WinDV manages it with buffers. So in short I don't think it is app specific but just that WinDV is smarter.
I then tested captures with Studio 8 to my RAID volume vs my ATA system drive. Capture to my single ATA drive was perfect. So as suggested earlier in the thread it would seem that my RAID 0 has some problems. That's a bit frustrating really given I spec'd all this based on other DV advice... anyhow...
In summary, I can continue to capture to my RAID 0 volume using WinDV OR reconfigure my system to 2 single SATA drives. I think I'll go for the latter despite the hassle as I've had an instance of my RAID volume "disappearing" once already.
One last question then... outside of capture does anyone know of good/bad reasons to keep/discard my RAID configuration (WRT video editing of course).
Thanks to all for your help on my frame drop problem.
Unless you have ATA33 or lower, I can' think of a reason to use RAID zero for single stream capture. It isn't needed and can cause problems.
It is needed for realtime capture cards that need 4-5 synchronized streams regardless of head position but I'd advise a dedicated RAID controller card for that.
Hard disk technology has evolved to where RAID isn't necessary for speed, and RAID 1 isn't advised for video capture unless carefully designed.
Cheers for the tips Ed-dv. I am capturing to an external 200gb NTFS drive. No anti virus as I never use this pc for the internet. I'v shut down as many background processes as I have found. I've captured 20gb AVI files with Windv with no problems using this method. I think that VS8 has a capturing hiccup with my pc for whatever reason. Any other MPEG on the fly capturing programs anyone can recommend?Why is it doing that?
Originally Posted by spurs61
No, I have no power savings set. And I don't have a screen saver. I actually sat and watched the capture for 10 minutes and clocked the dropped frames every 3.
Further to my test results I did a little more and DID get dropped frames with WinDV this time. It just seems to be a little more tolerant than PS8. But again, capturing to my ATA system drive... no problems, capturing to my RAID 0 drive... dropped frames!