Question about music video clip AV synchronization

Eugenia wrote on 7/21/2007, 12:25 AM
I have plans to put my HD camera in good use, by trying to shoot music video clips for local Bay Area indie rock bands. I won't accept compensation for the work, I will just do it for the experience and fun of it, and in the process, hopefully, I would produce good enough video clips to help the career of these local indie bands. Interestingly, I have enough free time in my hands to be able to do that and I personally already know 2 local bands to get started.

Now, problem is, that except my consumer HD camera which captures in amazing quality and even in 24p, the rest of my gear is limited. I have a few filters, a wide-angle lens, an extra battery, a fluid tripod head. I am not setup to record audio in a synchronized fashion with the playback music during a shooting like the pros do. So I would need to synchronize the audio in post manually, by using the band's mp3 file (which is what it would be used during shooting too, playing through a portable mp3/CD boom-player).

Now, my question is two fold:
1. What is the best way to synchronize the A/V, as they weren't recorded together? I understand that sync won't be 100% precise, but is there any trick to get close to perfection? Any tricks on how to move a clip in the timeline frame by frame for example until I get something that's good enough?

2. Let's say that I have several clips in the timeline, and while I am trying to synchronize a clip with the audio (e.g. a clip of the singer singing the exact words that the mp3 in the timeline currently is), I would need to move it about 60 frames on the left in order to achieve synchronization. When I do that, the video clip on the right will overlap a little with the video clip on the left. How do I split/delete these last 60 frames of the video on the left, so the video on the right is the only one at that timeline position? You see, synching the audio with a clip where the singer actually sings is more important and takes precedence of a clip that doesn't show the singer singing and so that second clip can do with a bit of trimming in order to achieve synching.

BTW, it's impossible to pre-trim clips on Trimmer for a music video clip where you need to sync audio on post and has lots and lots of few second-long scenes. Instead, I need a "trick", an intelligent way of moving clips on top of another as necessary overlapping a little, and then give precedence to one or the other and then delete only the portion that overlaps from the desired clip.

Ah, I hope I am making sense.

Comments

ritsmer wrote on 7/21/2007, 2:20 AM
Dunno if this may help :-) but if you download the last Full Vegas manual from
http://www.sonycreativesoftware.com/download/step2.asp?DID=696
and search for Synchronize - then several interresting things show up.
I have and use both Vegas's and sorry if I confuse the possibilities between VMSP and Full V.
Chienworks wrote on 7/21/2007, 6:24 AM
I do syncing manually by increasing the height of the audio tracks as large as possible and still have them fit on the screen. Then i zoom in until i'm seeing individual frames on the timeline. Then i merely slide the clips left or right to line up peaks in the audio waveform. It's a bit time consuming at first, but with practice it becomes quite easy.
OhMyGosh wrote on 7/21/2007, 8:18 AM
Hi Eugenia,
I'm not sure I understand all that you are trying to do here, but let's see if we can help a bit :)

1.' Any tricks on how to move a clip in the timeline frame by frame'
One way I do this is to make sure that 'number lock' is on, click on the desired frame, make sure it isn't grouped (unless of course you want to move all), then use the number '1' and '3' keys to move the clip one frame at a time right or left. You can use the '4' and '6' keys and that will move it 4 frames per click.
2.'How do I split/delete these last 60 frames of the video on the left, so the video on the right is the only one at that timeline position?'
I do this by putting the cursor where you want the split and hitting 'S', then click on the unwanted piece and hit 'delete', or put the cursor where you want it, go to the right or left edge of the clip in discussion, hover over the the edge until the edge of the clip has a rectangle with a double sided arrow showing, then left click and drag and snap it to the cursor (provided 'snapping' is enabled).
I hope you find something helpful here. Let us know. Cin
PS. A couple of tips to move the timeline cursor: 1. hit 'ctrl G' and that will highlight the time box near the bottom right of the timeline, and you can type in exactly where you want the cursor 2. Hold the 'Alt' button while you use your 'arrow' keys right or left and the cursor will advance by one frame at a time for precise editting. :)
Tim L wrote on 7/21/2007, 9:10 AM
(Boy this turned into a long post -- sorry if its too wordy)

One thing that can help when synchronizing anything with music -- even for simple slideshows -- is to use markers. Assume your main, continuous music track is on the timeline. Play the video, and hit the "M" key on each beat of the music, or maybe just the start of each measure. This will put a vertical line (ie a "marker") on your timeline/workspace. Doing this for the entire timeline might not be necessary -- just 20-30 seconds at a time as you are working on the video.

What probably a lot of people don't realize is that you can also add markers to a clip in the trimmer window (by the same method), and then those markers automatically appear in the clip whenever you drag it to the timeline. Short, vertical lines appear just on that video track. These can be used to align the video clips to the main markers on the timeline.

METHOD 1
If you are shooting a fixed stage setup with just one camera, you will probably record the entire song multiple times from different fixed angles, or from roving angles. Take each clip into the trimmer window, and add a marker at some prominent point near the beginning, and another near the end. Put your main MP3 on the audio timeline, play it and hit "M" on those same beats. (Since adding the markers manually in time with the beat might not be perfect, you can zoom in and manually adjust the markers by looking at the audio waveform.)

Now drag your 3 or 4 video tracks onto the timeline. Pick your most important track -- probably a closeup of the lead singer -- and put it full length on the timeline, on the lowest video track. You can leave this intact for the entire length of the song. Anywhere you don't have a clip above it, you will end up with a closeup of the lead singer, without having to resynchronize for every little piece.

Zoom in, and visually synch each track's "internal" starting marker with the main workspace marker. Go down to the end, and if the end markers don't match up, ctrl-stretch or shrink either the video or the audio to get everything to sync at the end as well. You can "solo" the various video tracks to test the synchronization.

Now its a matter of going through and soloing video where necessary to decide what clip you want during each part of the video. Split and delete as necessary, to get rid of upper tracks and let the lower tracks show through. As stated above, you can leave the lower track intact for the entire length of the video.

METHOD 2
Another way I think you can do it -- if you recorded the song full length 3 or 4 times (instead of in pieces) -- is to add one track to the timeline, then right click and drag the other clips on top of the first one, and "Add as Take". Now select this event, and each press of the "T" key ("take") will cycle through the 3 or 4 clips. On each one, press and hold the ALT key and then drag the clip left or right (inside the clip itself, not its edges) to synchronize the beginning beat. This is called "slipping". The start and end of the event on the timeline is fixed, but the positioning of the video within that event is adjusted. You should now be able to play the video, and each of the different takes should be synchronized.

Now go through and Split your video at the places you want to have changes. Now on each event, select a particular split section, and use the "T" key to cycle through the takes with that video. Each press of the "T" key will select the next clip of the 3 or 4 clips -- like stepping through 3 or 4 cameras on a switcher or something.

Hope this helps.

Tim L
Eugenia wrote on 7/21/2007, 12:00 PM
Thanks for the replies guys.

>putting the cursor where you want the split and hitting 'S', and then delete...

I tried this, but it doesn't work as I want it to. You see, at that point, I need to delete a few frames from the video on the left, which is the part that's overlapping at the moment with the clip on the right. I am not able to hit "delete" to delete only the overlapping part of the video on the left. The application deletes BOTH the overlapping parts of the clips on the left and the right, while I need it to delete only one of the two. Is it possible to only delete one of the two?

Tim, thanks for the two methods. Just one question: is it possible to have transitions between two clips on different tracks? With your methods, I understand that I will have a "master video track", but what if I need to do a transition between that and a clip on the above track?
Chienworks wrote on 7/21/2007, 1:43 PM
Things get a little tricky when clips overlap, especially when one is contained completely within the other. You have to select just the thing you want to delete by clicking on it. The default selection after doing a split is the part to the right, but you want the part to the left so you have to select it manually. Problem is, if that part is completely within the other overlapping clip then it may take more effort to select it. The first click might select the overlapping clip. You can tell this by seeing what gets highlighted (actually darkened). If it's the wrong thing then click again and Vegas will select the other item under the mouse cursor.

If it's still being too tricky, you could always press the numeric keypad down error. This will move the selected clip down to the next lower video track, creating one if necessary, if you're not already on track 4. Or, use the up arrow to move it up. That way the two clips won't overlap anymore. Delete the bit you want, then select the clip you moved and use the opposite arror key to move it back.

In general, yes, you can always delete just the part you want to. It just may take some extra clicking to select it. This is exactly the same as any other task that involves overlapping items such as page layout, CAD & drafting programs, drawing programs, layers and objects in photo editing programs, etc.

You can transition between clips on different tracks, but not with every option working perfectly as you might hope for. Add a fade out to the clip on the upper track for the duration you want of the transition. Add the transition to that faded area. For many transitions this will work pretty well. For other such as push or the 3D transitions you may also have to add a fade in to the lower clip and drag the same transition to that one. Some transitions such as threshhold won't work well at all because the transition effect requires accessing data from both clips, and that won't be available when using separate transitions.

edit ...

Oooh, another thought about the deleting problem ... if you really just want to remove a small bit from the left of the cursor position, it might be easier to trim instead of split. Leave the cursor at the cut position and drag the left edge of that clip to the cursor. No splitting and deleting necessary, and it accomplishes exactly the same task.
Eugenia wrote on 7/21/2007, 2:25 PM
Got it, thanks! :)

Now, it's all a matter of deciding if I want to do the synchronization only once or twice by using "master clips" with the singer actually singing and then drop unrelated scenes in the midst of it on other video tracks, or sync each clip individually on a single track and trim/split/sync all the time. I think each method has its ups and downs, depending on the nature of the music video clip.
4eyes wrote on 7/21/2007, 4:45 PM
In any case, using any compressed audio format can be hopeless for re-syncing. (I feel you already thought of this as a possible problem), so I would first convert the audio to uncompressed 48khz lpcm raw. You need an exact reference track.
This is what I use SMPTE Timecode for, there are many tricks one can use.
Here is the link for the SMPTE time code uses & descriptions, VMS can use & display SMPTE timecode. For NTSC you would want to use 29.97 dropframe.

http://en.wikipedia.org/wiki/SMPTE_time_code
Ivan Lietaert wrote on 7/23/2007, 3:39 AM
I've no experience at all but with it myself, but the following freeware programme may be of help: Double Take: http://vasst.com/product.aspx?id=2dcc4ca5-1aae-4c53-8a2c-b54213315da5
Eugenia wrote on 7/23/2007, 7:08 AM
Thanks, but I got only one camera. :)