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Maybe future capture cards just like 'bt-chipt' type cards now, will have those 'professional' type locks and good chips to maintain sync. For example the DV-capture cards (I don't remember what) usually, maybe always has that kind of locking. Only way to maintain av-sync is to do the routines in software (drop frames or adjust audio samplerate) or use hardware, that has audio and video chips in sync (singnal-clock-locked). I noticed almost no difference in terms of audio clock accuracy, when I compared the onboard sound to SB live 5.1. (in TV tuner cards there is internal 'on-card' audio chip, but there seems to be problem wih them too) I use just my motherboard audio input to record audio. But I think that there never will be such an option. If there were a somekind of "sync-clok-singal" cable from video chip to audio chip, there would be no av-desync. The problem lies in slightly different audio and video clocks in hardware. (normal vdub drops frames to maintain sync) I never drop a single frame, because the adjusted thing to maintain sync is audio track, not the video track as usually. #Miro dc30 xp driver fullI suppose it uses VFW-WDM wrapper but I still can capture in full PAL res (720x576) and 25 fps. I capture with virtual dyb sync (modification) which has routines to adjust audio sample rate to maintain av-sync. I use old WDM to avoid white box over the image when the source contains macrovision. #Miro dc30 xp driver driverThere is no other driver than WDM for gf cards. (sometimes I have to use v'dub filter called 'field delay' and delay top field to correct the interlaced movement displayed on TV) However the image quality is very good indeed. #Miro dc30 xp driver driversThe nvidia drivers are quite bad, because they ahve random field phase problem. I'd like to hear this issue have been resolved with wdm apps but AFAIK, only one app correctly captures. Well that might get you by for mpeg4 encodes but if you want to encode vcd or svcd/dvd, frame rate matters. Now again, you might say 'I've never noticed any sync issues so it's fine'. Even virtualdub itself when used for capture fails this test and Avery Lee addressed this in a usenet thread awhile back. Every application failed this test whether it was vfw or wdm application except one: AVI_IO. Do both fields say 29.97? Meaning the no change field and the 'change so video and audio durations match'. Go to video/frame rate option in the menu. Capture in your wdm app of choice and load the file in virtualdub. Now, you might say that you have not noticed any problems with audio sync but please try this test. I tried every wdm capture program I could find and all of them had a problem with audio sync. Now maybe the situation has gotten better, but last year, I tried the wdm drivers for my zoltrix tv genie over the vfw ones. Ignoring using btwincap, you must use wdm apps for wdm drivers to capture at full resolution. Now of course, on paper it is definately not the best tech, but in practice it's another story. #Miro dc30 xp driver pro
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