Problem with VirtualDub when editing... [HuffyYUV]

[kisk]

I'm trying to use VirtualDub to fix my audio sync problems, but my problem is when I try to playback my video (which is encoded with HuffyYUV) in VD, the audio skips real bad and there is no way I can fix the sync with it skipping like that. Is there anything I can do to fix this? Does it have anything to do with my video/audio source? The audio is PCM.

- kisk

[BJ_M]

did you try to defrag your Hd ?
did you try to use another hard drive ?

[kisk]

negative
negative

You think this would help? The video seems to play fine thru WinDVD and WMP, but the audio skips real bad with VD.

[Tommyknocker]

Did you try this guide?

[Poplar]

From my experience, and I don't know how to explain this: HuffYUV is a capture codec and not a play codec. Playing AVI in Huffy format isn't a good idea. In fact, I have never been able to play it smoothly on my computer. If there is a sync problem, you can identify and adjust them later, if you don't have tons of dropped frame. I almost have none.......

[HillJack]

kisk,

So you're trying to playback the file in VirtualDub, and the audio skips horribly. You've captured your video using the HuffYUV codec.

It's not your hard drive needing defragging.

Your computer is having trouble decoding the video AND playing it, AND playing the audio all at the same time -- A HuffYUV capture is a massive video file, regardless of audio and it's more than even the most powerful system can playback properly -- it's not a problem, it's just the computer can't keep up with all that going on -- Run TaskManager when you try to playback the video and I'll bet it's @ 100% CPU usage.

You "fix" that by going in to the Options menu, and enabling "Drop frames when behind" Now try playback. The video will LOOK choppy, but the audio will be perfectly smooth as VirtualDub is leaving out (dropping) video frames during playback since it can't keep the audio and video together.

Keep in mind that this only helps you with playback/preview. Enabling this option makes absolutely no difference to the final product I use this all the time when removing commercials from my vidcaps and checking the transitions for audio-pops.

[kisk]

hey thanks for the info hilljack. I tried using that option and it did clear up a bit, but still skips a little bit. Not too worried about it right this sec tho.

I have another question for ya tho
I'm using avisynth to automatically cut my commercials out in virtualdub:

AVISource("D:\blah.avi")
Trim(2510,3733)+Trim(5551,23110)+Trim(28548,47635)

... the file is HuffYUV, but after loading it into Virtualdub with avisynth, when I save the avi, it saves as MS-YUV which is much bigger and I simply don't have the space to use it. Is the problem that I'm using AVISource instead of DirectShowSource? I tried using DirectShowSource instead of AVISource and my processor skyrocketed in virtualdub. I let it sit for a little while but it wouldn't stop. Anyway around this? Will it eventually finish blowin up my processor?

Thanks,
- kisk

[kisk]

ok... just an update ... I found that if I let virtualdub sit there for a little while after loading my HuffYUV clip with "DirectShowSource" via avisynth I can save it. My problem now is when I save it, it saves as uncompressed video and when I play it, there is a caption at the top that flashes "Video Desync!"

Why? 8)

[BJ_M]

you didnt select a compression type in video ->compression

[kisk]

Well I was opening a HuffYUV so I was trying to just use stream instead of processing... guess the DirectShowSource takes away my ability to do this?

[HillJack]

Why are you even bothering with Avisynth? Are you doing more than just removing commercials? Just do it in VirtualDub, and fire up the built-in frameserver and go from there... save yourself the hassles?

I don't get why people bother with avisynth... Atleast they could give you a GUI of SOME SORT... this is Windows afterall, not DOS... so VirtualDub takes a bit longer, big deal... I'm a patient person

[kisk]

Well the reason I'm trying (and I do mean trying -- I'm new to the vid scene and just testing different stuff out) is cause I'd like to get around the whole audio out-of-sync problem. I initially came up with the problem of the audio sync while straight cutting out the commericals thru VirtualDub. The first scene sync's great, 2nd sounds/looks good, but when I get to the 3rd I can tell the audio is getting unsync'd bad, and by the time I get to my last cut scene, the audio is 1.5sec off. I was thinking it might have something to do with VirtualDubs cutting algorithms.

So basically I'm just testing if "cutting" with avisynth as I open in VirtualDub will help out my audio sync problems when I save. I'm saving my avisynth'd cut in VirtualDub right now so I'll post the results when they're done.

- kisk

[HillJack]

But, I assume you will be converting the edited video using something like TMPGenc, or Premiere, or whatever else there is? Does the program you use support VirtualDub's frameserver files? If so, trust me, just forget all the workarounds and go straight from VirtualDub...

I've NEVER "Saved" an edited clip in VirtualDub, I've ALWAYS used the frameserver, and I've NEVER had a synch issue feeding to TMPGenc.

Cut the commercials, apply any filters, save the configuration (I can't remember what its called exactly... "Save Current Settings" I think?) which produces a whopping 1kb file with references to the removed frames and any filter settings needed... takes all of 0.0002 seconds. Should the need arise to reload those later on, load the original unmodified avi, and load the settings.. poof, you're back to your "edited" video.. Takes all of 0.005 seconds. Then fire up the frameserver and feed the "edited" video into whatever program you're using. It's the best thing since sliced bread, absolutely zero hassle

I've heard of others who have synch issues trying to save out their edited video, and I've always wonderered, "why bother" when the frameserver is built right in.

[kisk]

Actually, after I left my last post I starting thinking about the whole frameserve idea. Let me go ahead and repeat -- I'm very new around here and eager to learn the best methods. HillJack, yes I am planning on going from VirtualDub to Tmpgenc... could you point me to a tutorial covering these two tools (concerning frameserving)? Skipping "saving" in VirtualDub would be nice. Do you get audio sync problems with frameserving to Tmpgenc?

BTW, I finished my test. Results were interesting (for meh, hehe). I thought I'd share my results just in case others came across the post. The same video was used in both tests...

Test1: I open'd my HuffYUV vid in VirtualDub and proceeded to cut out the commercials straight from VirtualDub. Then, I saved my avi using Video: Direct Stream Copy and Audio: Direct Stream Copy.

Test2: I used VirtualDub to get all my frame points that were cut in first test and created a avisynth script that would cut out my commercials before loading it into VirtualDub:

AVISource("D:\blah.avi")
Trim(2510,3733)+Trim(5551,23110)+Trim(28548,47635) +Trim(49000,52689)

I then saved my avi using Video: Full Processing Mode with the same compression [HuffyYUV], and Audio: Direct Stream Copy.

-------

Results1: Segments 1 & 2 of the saved avi sync'd good. The 3rd segment's audio was ~.5sec off and the 4th segment's audio was ~1.5secs off. Variable audio sync problems.

Results2: The completed vid turned out great. All segment's audio was in sync. All looks good.

Could this possibly mean that VirtualDub's cutting abilities are not without flaws? Of course it's naive to say any program is flawless, but from this test it looks like there might be a few things that should be worked out with VD. I must say I'm very new at all this so these are all just speculation. It could also be the fact that I used full processing with the second test opposed to streaming with the first. Any comments are welcome.

I also have yet to do anything past this test (check for bad frames, encode to mpeg2) so testing isn't really done!

Anyway, HillJack, those frameserve tutorials are welcomed

[HillJack]

but my problem is when I try to playback my video (which is encoded with HuffyYUV) in VD, the audio skips real bad and there is no way I can fix the sync with it skipping like that. Is there anything I can do to fix this?

You "fix" that by going in to the Options menu, and enabling "Drop frames when behind" Now try playback. The video will LOOK choppy, but the audio will be perfectly smooth as VirtualDub is leaving out (dropping) video frames during playback since it can't keep the audio and video together.

hey thanks for the info hilljack. I tried using that option and it did clear up a bit, but still skips a little bit.

kisk, I don't know if you're still having that "problem" or what version of VirtualDub you were/are using, but I just ran in to this problem for the first time ever this morning -- even with "Drop Frames When Behind" enabled, VD would still studder horribly. Wtf?

I WAS using VD 1.5.9 and tried 1.5.10, neither helped. So, I reverted back to 1.4.9 and VIOLA! "Drop Frames When Behind" actually works -- it must be a change in some successive version of VirtualDub that makes it studder. IOW, if it still studders for you, use v1.4.9 and it should fix it

Hope that helps.