dv dropped frames

[Impala_SS]

I have a Sony HC42 miniDV cam, I hooked it to my notebook via firewire. My notebook is P4 2.4, 256 mb ram(16mb used by the video card), external usb 2, 40gb samsung drive with ntfs, 7200rpm), Win XP SP1(no updates). I closed all TSR programs from msconfig, no Internet, no virus scanner or firewall, no wallpaper, DMA is on. When I try to capture from MiniDV cam, in certain frames, it drops 138,142 frames. I am using WinDV. What is the solution for this?

[mwkurt]

It could be a couple things. Have you defragged your hard drive lately? Are you trying to capture to your system hard drive. That is usually a bad idea. Also...you could probably stand a bit more memory.
Mark

[GeorgeW]

I have a Sony HC42 miniDV cam, I hooked it to my notebook via firewire. My notebook is P4 2.4, 256 mb ram(16mb used by the video card), external usb 2, 40gb samsung drive with ntfs, 7200rpm), Win XP SP1(no updates). I closed all TSR programs from msconfig, no Internet, no virus scanner or firewall, no wallpaper, DMA is on. When I try to capture from MiniDV cam, in certain frames, it drops 138,142 frames. I am using WinDV. What is the solution for this?

are you sure about that frame count? where are you seeing that frame count?

if you are capturing dv type-2, try dv-type-1 instead to see if it helps...

EDIT:
just noticed you are using an external USB2 drive? If so, are you connected to a USB 2.0 port? What is your read/write throughput of that drive? Do a search on Raptest.exe (from Canopus), it can show you the read/write performance of your drive.

[Impala_SS]

I am using an empty hdd for capturing, I tested it with Sisoft Sandra, it is fast enough. It's connected through usb2. I saw those frame drops in Windv.

[GeorgeW]

138,142 dropped frames is about 77 minutes for NTSC, and about 92 minutes for PAL DV .avi capture. Something doesn't sound right

What speed did Sandra report on the capture HDD?

Are you capturing DV Type-1 or Type-2?

[Impala_SS]

It's 138 or 142 frames(~5sec). I am trying type 1 avi, what about the codecs, should I use Panasonic codec for capturing dv? 18 mb in Sandra Sisoft.

[GeorgeW]

138 or 142, ok that makes more sense (not that you should be dropping any).

Did the Type-1 do any better?

I didn't think you can specify the dv codec for capture. Does WinDV let you do that???

I'll assume 18mb is your WRITE speed?

[guns1inger]

You don't specify a codec for DV. You aren't capturing, you are transfering a file from tape to disk that just happens to contain video data. The Panasonic DV code is required only for playback through virtualdub. You can still potentially lose frames because of the way the data is transferred, though.

If I understand you correctly, you are transfering via firewire and a laptop to an external HDD connected via USB2. While each should be fast enough in their own right, there may be issues with using a chain like this. If you have the space, I'd try going to the laptop HDD first, then shifting the file to the external HDD afterwards.

The other approach would be to see if the dropped frames are clustered into a small period of time, and just retransfer those bits later and edit them back in.

[Impala_SS]

Both drives are dropping frames, no way. I will try adding 256mb more memory. This problem exists in the same regions(frames).

[GeorgeW]

Both drives are dropping frames, no way. I will try adding 256mb more memory. This problem exists in the same regions(frames).

maybe your source video is corrupt??? since it is in the same regions (frames) being dropped repeatedly???

[DEC]

My digital 8 will do the same thing if it hits a spot on the tape where there is no actual video. If its @ a place in the source where there is a break dont worry about.

[guns1inger]

As DEC has pointed out, it could be a break in the time code. Have you veiwed this are to see if you have actually lost anything ?

[Impala_SS]

I used several tapes, both have dropped frames, I watched the videos there weren't any empty scenes. Also I shoot a new video on a new Panasonic tape, same results, in the certain places it drops. I recorded video without a tape(like webcam but connected vie firewire), same things happen after a while. It isn't too much frames for a 10min video, but I know that in firewire you can't loose frames.

[guns1inger]

That's actually a myth. It transfers in real time, so if for some reason your machine can't keep up, it will shed data in order to keep the transfer going.

[Richard_G]

Have you got power saving enabled on the computer? It sounds more like something is happening to block the disc writing for a few seconds. It may be that the hard drive is turning off and then back on again.

[Impala_SS]

I closed all power saving operations, also this thing occurs everytime, when the system is hot or not, it doesn't matter.