Huge frame drop from Virtual VCR

[freshie]

I was having problem with audio video out of sync using Studio 8.12.7 to capture vhs video via DV pass through as well as via WinFast TV2000XP capture card

Both capture method did not produce much frames drop and the capture videos were not jerky but the audio video sync were out from 2 seconds to 26 seconds

I read about virtualdub & virtual vcr and was attracted to virtual vcr on dynamically resampling audio to bring audio in line withe the video frame rate

I tried few captures with virtual vcr for short periods of less than 5 minutes each. There were huge frames drops, eg 3059 frames captured, dropped frames 2 was 3968 frames!!

I also noticed that the video frame was not 25fps as set for PAL but was varying from 24.94+ to 25.04+fps

The captured videos were very jerky and cannot be used. Also Studio 8.12.7 could not open some of them especially those with HuffYUV codecs and took a long time to detect scenes for those with DV video codecs

Can anybody give me a clue on what I am doing wrong and guide me to the correct path?

[freshie]

I tried using CaptureFlux yesterday to capture vhs video via WinFast TV2000XP capture card but did not have good results with RGB24 colour settings in PAL

The file was huge 3GB for 2 minutes of video & the video was jerky

Does anybody have any experience with CaptureFlux and can share what is required to be done?

[Ghitulescu]

I was having problem with audio video out of sync using Studio 8.12.7 to capture vhs video via DV pass through as well as via WinFast TV2000XP capture card

Both capture method did not produce much frames drop and the capture videos were not jerky but the audio video sync were out from 2 seconds to 26 seconds

I read about virtualdub & virtual vcr and was attracted to virtual vcr on dynamically resampling audio to bring audio in line withe the video frame rate

I tried few captures with virtual vcr for short periods of less than 5 minutes each. There were huge frames drops, eg 3059 frames captured, dropped frames 2 was 3968 frames!!

I also noticed that the video frame was not 25fps as set for PAL but was varying from 24.94+ to 25.04+fps

The captured videos were very jerky and cannot be used. Also Studio 8.12.7 could not open some of them especially those with HuffYUV codecs and took a long time to detect scenes for those with DV video codecs

Can anybody give me a clue on what I am doing wrong and guide me to the correct path?


Read this - http://forum.doom9.org/showthread.php?p=1282320#post1282320

if your VHS is ok (no drop-outs in video due to synch errors - most pass-through camcorders play a blue screen when they loose the synch, use a TBC then), then the audio-video synch is maintained.

But, using DV resolution for VHS is a bit overkilling. Why not use a DVD-recorder in 352x576i (x480i) mode? The tape has no more than 250-300 lines of resolution ...

[freshie]

Hi Ghitulescu

Thanks for your post. What is "TBC" which you mentioned in your post?

You mean when the video - audio get out of sync, the pass through camcorder will play a blue screen so as to maintain the sync?

I will try capturing with lower horizontal resolution but maintaining 576 for vertical to see if will help solve my problem. But will the video display correctly after editing and rendering to DVD and playback on PAL TV?

Have you any comments or advice on virtual VCR or CaptureFlux especially the problems which I had described in my previous posts.

CaptureFlux is produced by the same person who produced DVDate

[Ghitulescu]

Hi Ghitulescu

Thanks for your post. What is "TBC" which you mentioned in your post?

You mean when the video - audio get out of sync, the pass through camcorder will play a blue screen so as to maintain the sync?

I will try capturing with lower horizontal resolution but maintaining 576 for vertical to see if will help solve my problem. But will the video display correctly after editing and rendering to DVD and playback on PAL TV?

Have you any comments or advice on virtual VCR or CaptureFlux especially the problems which I had described in my previous posts.

CaptureFlux is produced by the same person who produced DVDate

I think you really need to read more.
TBC - Time Base Corrector - corrects errors of reading, outputs a stable signal
if you have timing errors (synch errors, there are corrected by a TBC) then almost every DV/D8 camcorder in pass-through will output a blue screen instead of the image because it has none to display
I wanted simply to say that if you have timing errors (synch) on your tape, that force the blue screen, you may end with audio video not being in synch.
704x576i, 720x576i, 352x576i, 352x288p are all valid DVD resolutions. The last one can also be MPEG-1 (sure you heard about VCD).
Your problem can only occur if synch errors (timing - use a TBC) or if you get your video with a capture card and the audio with another (or a cheap card), because their internal oscillators (time base) may vary (you know I assume the Murphy's law about a man with 2 watches). But if you use dv-in should be no problems, use the simplest proggie you may find