Frames inserted in VirtualDub

[GovertdeKat]

Hello Everybody,

I am capturing my VHS/HI8 tapes using the following set-up:

VHS/CAMCORDER == S-VIDEO == PANASONIC DMR-ES10 == S-VIDEO == COMPUTER/VIRTUALDUB

Everything went pretty well with all my VHS tapes, but my HI8 tapes are giving some trouble. For some reason VirtualDub is inserting al lot of frames and the videos don't look smooth at all. This really happens only when I start capturing. When I test the video capture it doesn't show any inserted frames. Also when I capture using the provided software of the capture card it doesn't show any problems. But I want to use VirtualDub off course.

I am missing some adjustment in VirtualDub?

[Bernix]

Is framerate from software comes with captured card same as your VHS captured with Virtualdub, or are they different?
Edit: I mean the capture, that comes bad from virtualdub of course.
Bernix

[jagabo]

Disable audio playback in VirtualDub while capturing.
Use a fast video compression codec like huffyuv while capturing.
Do not compress audio while capturing.
Try different settings in Capture -> Timing.

[GovertdeKat]

The settings of the capture software are the same as VirtualDub as far as I can see. Both capture settings are PAL_B with 25 fps.

I am using the huffyuv as compression now and the audio is not compressed. Also I disabled the audio playback as well as the video playback.

The results are a lot better, but I am still losing some frames.

Can you tell me what I can adjust in de timing settings? My setting are as below:


[Attachment 44216 - Click to enlarge]

[jagabo]

Try enabling "Do not resync between audio and video streams".

Make sure you are capturing YUY2 or other YUV 4:2:2 chroma subsampling, not RGB.

[GovertdeKat]

Turning off the internet connection seems to be the simple solution here. Nore more frames inserted strangly.

[LMotlow]

Can you tell me what I can adjust in de timing settings? My setting are as below:


[Attachment 44216 - Click to enlarge]

I don't know of anyone who uses the settings you've shown. Settings also depend on the capture device, for which you've given us zero information. virtualdub capture advanced settings guide.

[eduolfer]

Hi.
the audio and video cables, the problem in fact may be these. Measure the tips with a multimeter, they must have 0 ohms (or a close value). if they are on 1 ohm around, believe me, this will cause sync problems.

[dellsam34]

A 5 years late response that doesn't address the problem Inserted frames has absolutely nothing to do with analog audio cables and their impedance.

[lordsmurf]

A 5 years late response that doesn't address the problem Inserted frames has absolutely nothing to do with analog audio cables and their impedance.

But ... hmm?
What if the video card dropped in the absence of any audio input, when a non-timed video input was used?
That's not the case here (ES10/15) but interesting to think about.

That said, skimming thread quickly, card not mentioned, and OP probably using crap (Easycap, Elgato, whatever). 5 years ago, doesn't matter now.

[dellsam34]

Even with the absence of analog audio signal the ADC would still produce a digital audio clock, If that's the case capture cards will drop frames every time there is a silence in a video scene, Though the OP is talking about inserted frames not dropped frames.

[eduolfer]

Hi guys, I do a lot of conversions and use several capture cards, in all cases of inserted frames (even using a tbc) I found dirt, bad contact, deteriorated wire etc causing the problem, I use virtualdub. the problem happened even after about 40 minutes of capture... and didn't stop inserting frames. the possible solutions that I found on the web, did not work, so I decided to post here in the possibility of helping.

[dellsam34]

You may have fixed the problem in a different way and that coincided with replacing audio cables, Bad USB cables could indeed cause that but never the audio cables.

[eduolfer]

I state my first post: it was the audio cables, in most of my frame inserting problems. Virtuadub reported high amount of desync on status screen.It was resolved by replacing it with new cables or repair.But I believe this solution would be one of the last to try.

[dellsam34]

I'm glad you fixed your problem however analog audio has nothing to do with frame count after the ADC.

[eduolfer]

I noticed that the latency of the audio passed 300ms ( Sync current error info) and that was how the problems started...Do you have any suggestions that could cause frame inserting ?

[jagabo]

An electrical signal in a wire passes at near the speed of light. You would need 90,000,000 meters of cable to get a 300ms delay.

I wouldn't go as far as to say a bad audio cable couldn't cause dropped/added frames. It's always possible there an issue like a ground loop or induced noise that might screw up the video's sync signal. But I think it will rarely be the case.

[eduolfer]

OK, but if the wire has a resistance of a few ohms it is possible to have a problem with the signal, in my case I had cables with about 3 ohms ... due to internal oxidation.

[jagabo]

OK, but if the wire has a resistance of a few ohms it is possible to have a problem with the signal, in my case I had cables with about 3 ohms ... due to internal oxidation.

That would only reduce the volume, and possibly the high frequency response. It would not interfere with the video signal at all. You could use no audio cables at all (~infinite ohms) and there would be no interference with the video, you would just get silent (maybe a little noise) audio.

[eduolfer]

Yes, I completely agree that it does not influence the video, but my observation would be the synchronization of the video with the audio.. the audio would be out of "step" with the video. would my deduction be incorrect my dear ?

[dellsam34]

What you are saying could be possible only if you are messing with the digital transmission such as the USB cable, The ADC can care less what's going on the VCR side, Like Jagabo said it could be a ground loop issue that screwed up the video blanking signal that is responsible on timing the frames, If the capture card senses the absence of the VBI signal it may improvise by inserting the missing frames, Even though this would be a rare occurrence.

[jagabo]

Yes, I completely agree that it does not influence the video, but my observation would be the synchronization of the video with the audio.. the audio would be out of "step" with the video. would my deduction be incorrect my dear ?

The audio would not be significantly delayed or advanced by a high resistance cable. The ADC would only see a lower voltage -- which would appear as a lower volume.

If loss of audio signal strength caused sync errors you would have problems any time the audio was very quiet or silent.

[eduolfer]

Hi Jagabo. This explanation I understand refers to the internal part of the circuits... in the case of vcr, K7 player etc... technically, the cable impedance would be modified due to the defective cable, that's what I define my diagnosis. In a correct way, I deduce it to be an impedance problem.

[jagabo]

Regardless of the impedance the audio ADC will continue sampling at the same frequency. There will be no changes to the sync.

[eduolfer]

Tks, I will try to better understand what I found to solve the problem.

[Lunacy]

Hello, i encountered a similar problem with my setup: Sony Camcorder connected via Composite to DMR-ES15, then Composite to GV-USB2, all managed through VirtualDub.

I managed to solve the issue by turning off "Enable Audio Playback" in the Audio menu dropdown. With it enabled during an 11-minute test capture, I experienced 153 inserted frames, causing noticeable stuttering in the video playback. However, once I disabled audio playback, I only encountered 2 inserted frames at the very start of the capture, still during the same 11-minute test.

Hope this is helpful to anyone facing a similar issue in the future.

[eduolfer]

Very good, this procedure is one of the first to do, as suggested in the virtualdub manual. There are other causes such as: processor power management, capture card driver, hard disk with badblocks, you can check the system latency to see if there is anything interfering (dpclat), connection cables, etc...