Jerky capture with duplicated frames

[putte67]

I try to capture PAL video from a Hi8 camera with a Leadtek WinFast TV2000 XP Expert capture card with PicVideo MJPEG encoder on WinXPSP2 for further editing. The problem is that after 25 frames the 25th frame is duplicated 15 times (inserted), after which 25 frames are captured normally again, an so on. The sound however is captured as expected making it 15/40 times shorter than the video. I have been able to pin down this numbers by stepping one frame at a time in my video editor.

I suspected something was wrong with either PicVideo or the drivers for the capture card so I re-installed it all but without success. Since I've been able to capture video correctly a couple of months ago with this setup I then suspected it had something to do with some new service or program I've installed. I then tried to stop as many services as possible without shutting down the system. Since that had no effect I tried to log in as the administrator instead of my normal account, and there it suddenly worked!! I have compared the running processes and services between the admin account and my normal and nothing strange came up.

Of cource I can capture all video in the future with the admin account and then switch to my normal account for editing, but now I'm curious and I want to find the reason.

[themaster1]

picvideo codec is a piece of crap i tell you
best mjpeg codec is morgan m-jpeg but even the best mjpeg codec doesn't equals a mpg or xvid codec in my opinion.

They leave too much noticeable artifacts

if you got some space on ur HD try a lossless codec like huffyuv or lagarith(couldn't make it work this one but it's supposedly better than huffyuv )

[putte67]

Maybe, maybe not. I've managed to capture with this codec before and the quality was superb. But that wasn't the question here. I was asking for help and not an opinion. The question is why it's acting as it is and how do I resolve it? It can be that it's not about the codec at all, and the problem is completely somewhere else. Please... anyone?

I also forgot to say before, I don't have a single dropped frame, quite the opposite.

[manono]

how do I resolve it?

Avisynth:

TDecimate(Mode=1,Cycle=40,CycleR=15)

should remove the 15 duplicate frames in every cycle of 40 frames. TDecimate is part of the TIVTC filter, so you have to load the TIVTC.dll.

Or, if you're absolutely sure that after every run of 25 good frames you get 15 duplicate frames:

SelectEvery(40, 0,1,2,3,....24)

Fill in all the other missing frame numbers. That will choose the first 25 frame numbers in every 40 frames. It also assumes that the cycle is constant, and that you get 25 good frames before the dupes begin. That is, it'll have to be adjusted if you get 15 good frames followed by 15 dupes, followed by 10 good frames again, in a cycle. And if the pattern changes at all (more or less frames in the cycle, more or less dupes in a cycle), you're screwed, unless you adjust. SelectEvery is a built in filter, so nothing additional has to be loaded into the script.

As far as I know, AviSynth is the only way to resolve a problem like this.