VideoStudio 11: Audio syncing

[Sephirex]

I'm doing a parody video in which I need a clip from a show playing. The clip plays but the audio is WAY off, often starting from before the clip even started. I've tried Copy & Pasting the Audio, Spliting the Audio, and everything else I can think of but nothing works. The wierd thing is that if I just highlight the audio and play it by itself, it goes perfectly, but when I play it with the rest of the video it's still wrong. How do I get the audio to sync with the video properly?

[Ken Berry]

I am afraid no one could provide a sensible answer with the amount of information you have provided. Can you please tell us (by right clicking on it within the Video Studio timeline) all the Properties of the file in question, where it came from and how it was captured. Also, we need to know whether you are trying to convert it into something else, and if so, what your project properties are. It would also be greatly appreciated if you would fill out your Profile so that we don't have to ask you each time what your computer specifications and system details are. Thank you in advance.

[Sephirex]

Well I downloaded the file and it's AVI Format. The video compression is DivX® 6.8.3 Codec (2 Logical CPUs), with Attributes 24 bits, 640 x 480. The Audio Compression is MPEG Layer-3, with Attributes are 119 kBit/s, 48 000 Hz, Stereo.

As for my computer specs, I'll fill them out Asap.

[Ken Berry]

Since you can actually play the clip, I guess we can assume you have the DivX codec installed on your computer. Does the clip play in the (free?) DivX player with the video and audio in sync? It could be off slightly...

Next, you need to be aware that DivX and XVid, while providing high quality video in a very small file size, is very highly compressed to achieve this file size. Such formats are meant for presentation rather than editing. So we also need to know what you intend to do with your overall project. If you are intending to burn a standard definition DVD, then it probably better to convert the DivX to DVD-compatible mpeg-2 before you even open it in Video Studio. There are a number of free conversion programs out there, though a number of us here use one called SUPER which can be downloaded from www.erightsoft.com/SUPER.html

[Sephirex]

Well I'm not trying to change the format to anything. I'm just trying to edit a video and post it on the internet, I don't want to burn it.

Also, i don't usually use DiVX I usually use VLC or Windows Media Player. I tried a few files on the free DiVX player. The video that is roughly 90% of the video I'm making only plays for 2 seconds on it and then stops. Any other video I'm using for what I'm making plays properly but not when it's in VideoStudio.

[Ken Berry]

If the DivX player won't even play more than 2 seconds of a video made with its own codec, then that suggests to me that there is something seriously wrong with the video itself. However, I confess I have no experience in troubleshooting DivX video...

[patricio_latorre2004]

Hello. I have an HDR-HC7. I have captured the video to the HDD already and no problem. Then I edited the videos cropping and cutting everything letting just small videos (30 secs to 2 minutes long). Then I started to try different formats of HD videos (bluray, HDDVD, H264 and HDV 1080i 60i).

Whenever i try transitions, any transition I get audio sync problems using HDV 1080i 60i (that is the format where I dont loose any bitrate) after 20 minutes of video I get around 1 sec sync problems (audio sounds about 1 sec fater than I should). When I try bluray, hddvd or H264 I dont have the audio sync problem BUT I loose bitrate (from 25-30 megabits per sec downgrade to 10) How can I get it right? I have tried uninstalling the vista codec pack 4.7.0, trying a fresh install, tried using Windows XP SP2 and SP3, latest drivers, latest firmwares, latets updates (all windows updates available to date) and I dont get it right yet, I'm using 11.5 plus.

Please any help???

[Ken Berry]

Hola Patricio! Sea bienvenido al foro! Yo pasei dos años en Las Condes (1996-97). Entonces, conosco bien su país...

I am not sure that you have the same problem as Sephirex. You are using a camera which films in the HDV/high definition mpeg-2 format. First, can you tell us whether you used Video Studio to capture your video. If you did, then it would all have been captured as one large file. And if you put this large file on the timeline of Video Studio, then any cuts you make to it, are virtual ones, rather than real ones.

All high definition video is very sensitive when it comes to cutting and editing, so you have to get the 'Group of Pictures' (GOP) aspect right. If I remember correctly, HDV uses a GOP of 15. But it you cut into the middle of the GOP, then the video is likely to be stopped at the end of the last full GOP but a little of the audio stream might continue for a few frames. If you do this for quite a few clips, and move the virtual clips around a lot on the timeline, then after a while, I suspect this is what causes the audio to get out of sync cumulatively.

I have a Canon HV20 which is also a HDV camera. And I have so far avoided any problems with out of sync audio and video by not capturing with Video Studio. I use a small freeware program called HDV Split. As the name implies, during capturing, HDV Split creates lots of real (and not virtual) little clips of your scenes. You can still edit these, and you can of course move them anywhere you like on the timeline. But it seems to avoid any out of sync problems.

I am also a little surprised that you say you get low bitrates with other high def formats. I would have thought you could maintain the HDV native bitrate of 25000 kbps if you chose Blu-Ray, HDDVD or HDV as the output format. The VS default for H.264/AVCHD seems to be VBR 15000 kbps rather than a more realistic 17000 or 18000 kbps, but is certainly not as low as 10000 either.

Anyway, what I personally do to produce a new file in exactly the same format as the original, including the 25000 kbps bitrate, is not actually to go to Share > Create Video File to process my edited HDV. Instead, I choose Share > HDV Recording. This is meant to send your edited video back to your camera. But it first creates a new HDV file of the edited project (you have to give it a name). And even if you have no intention of sending it to your camera, simply don't connect the camera. VS11.5+ will still create the new file in HDV transport stream format, and then will give you a message that it can't find any camera to send it to. You click OK and have your file. I have done all this many times now and never had one out of sync problem.

[patricio_latorre2004]

Excellent Ken, great site. Hope to be part of the community as I learn more about editing.

Well, first of all sorry for my english, I tried my best, but when I read myself I'm ashamed.

Now to the problem itselft. I use the software that Sony provides to capture the software. It creates small videos (one video per recording).
It creates an *.m2t file.

I have been about 3 weeks cutting the videos (taking long captures out and letting just the fun stuff) creating new videos (small ones) all in HDV 1080i 60i PC I mean for example if i have a 2 min video I just take from second 22 to second 57 and create a new video with what just happened between second 22 and 57.

The problem is when i take these videos to the timeline, (for example 40 videos that all toguether are about 20 minutes long and I add transitions (crossfade, flasback 4 and so on) using HDV 1080i 60i (that is the best quality that I have noticed (not downgraded from the original) when I play the final result with the trasnitions there is an audio delay.

Sorry to ask. What is GOP?

I will try HDV recording and let you know in a little while. These is not letting me sleep well, ahahahaha, I already want my vacations on bluray but cant get it right yet to surprise the family!!!!!

Well Ken, hope you are around yet, I will be trying to get the HDV recording file......

Thanks a lot.


WELL, I ALREADY FINISH TWO DIFFERENT FILES. ONE IS USING "SAME AS FIRST VIDEO CLIP" AND THE OTHER USING "HDV RECORDING 1080I 60I" AND GOT THE AUDIO SYNC PROBLEM AS WELL, SO MY NIGHTMARE CONTINUES........

[Ken Berry]

It creates small videos (one video per recording).

I am not sure what you mean by this. The mini DV tape in your camera can hold one hour of video. Do you mean the Sony software creates a one hour long file? Or do you mean it splits it into one video per scene? If it does this, then it is like HDV Split.

I have been about 3 weeks cutting the videos ... creating new videos

Again, I am not quite sure what you mean here. What program are you using to cut the videos and create new ones? If it is VS11.5+, then do I understand you correctly that you are doing your edits on the original video, then going to Share > Create Video File > HDV for each one? Then when each of these is finished you are re-rendering them a second time but this time into one big video?

If that is so, then it is really not a very good idea. As I said originally, mpeg-2 and especially high definition mpeg-2 is sensitive to all sorts of things. It is also a lossy format, which means that each time it is rendered, it loses quality. So you should try to keep the number of times you are re-rendering very low or you will cumulatively lose quality each time.

Why not put one small video in the timeline, and do your edits. Then put the next one in the timeline beside the first one, and edit that. Then do the same with a third and fourth etc, until you have them all in the timeline and edited. And save it all, so that all the edits are recorded in a Video Studio Project (.VSP) file. And then you only need to do one render to a new file.

The other thing you might want to try with this workflow is, when you finally go to Share > Create Video File > HDV, a dialogue box appears asking you to give the new file a name. Click the Options button on that box, and un-tick 'Perform SmartRender'. That often stops out of sync problems for people who are having the trouble.

As for what a GOP is, you should probably do a Google search for it. But essentially, it is the heart of what an mpeg file is and what makes the mpeg file relatively compressed and smaller. Essentially, an mpeg video stream is made up of a series of groups of pictures (GOPs), each of which starts with a header and what is called an I frame. There is only one I frame in one GOP. The other 'pictures' in the GOP are called B and P frames.

Most of the information relevant to that sequence of frames is contained in the I frame and the succeeding frames in that GOP are processed according to the information in the I frame, reducing overall the amount of information/data being carried by the full video stream and thus also reducing the size of the overall video file.

But if you cut in the middle of a GOP, you will have, on one side, an I frame with all the information, followed by a few B and P frames, but not the full GOP; and after the cut, you will have the remaining B and P frames but no longer connected to the I frame which contains the information relevant to them.

Please understand that I am simplifying all this very much. The subject of GOPs is incredibly complex and indeed people have written very long papers on it...

[patricio_latorre2004]

I appreciate all the help, but he facts are:

I used another software to create a big video (placing together all the small ones) more than 500 hundreds videos, creating a 56 gb video file, with 25 megabits per sec of bitrate with crossfade transition and the is no audio delay problem.

So the video files are OK and there is no loss of information in the encoded videos.

The problem is that I really like videostudio. I love the flashback 4 transition effect and I would love to hear that there is or there will be a solution (maybe in Video Studio 12) but if I dont hear about recognizing the problem that obviously wont happen.

Any suggestions??

now, about doing all the videos in a timeline, that would be an option to try and see if the problem wont happen, but imagine 20 hours of HD video and creating another 15 hours, I think there in no computer that can handle that, hahahaha. At least I think mine doesnt..

The other fact is that using the type of enconding (HDV 1080i 60i for PC, or for HDV, or DHV recording, or Bluray, or HD DVD) with no thansitions the audio delay DOESNT HAPPEN, so the problem are the transitions, hope to hear from you soon, and thanks for all the help so far.

[Ken Berry]

Sorry, but I can't think of anything else. My HDV projects all use transitions, and lots of them, and I don't have any problems. However, I would note that I don't use any of the fancy transitions -- usually just a cross-fade. So your problem could be related to the flashback transition if you use it a lot. I just don't know.

Have you tried my suggestion of rendering with SmartRender turned off?