How to do a strobe effect

liquid wrote on 1/6/2011, 4:11 PM
I want to cut certain segments of a video to create a strobe effect as seen here.



Simply splicing would be difficult to have even segments. Are there any other ways to do this, short of paying for a script?

I've downloaded a demo version of Excalibur, but I can't figure out the strobe effect and I can't find any tutorials on it either.

Comments

john_dennis wrote on 1/6/2011, 5:29 PM
In the example link, the video appeared to be swapping between two different tracks. Have you considered placing two events on the timeline, one on top of the other, then removing a few frames of the top one letting the bottom one show through? You could do that repeatedly for as long as you want the effect. That's the boring, time-consuming way that came to mind first. There is likely a more automated way to do it.
farss wrote on 1/6/2011, 5:35 PM
"Are there any other ways to do this"

After watching the 18+ version of that video you bring that talent to a shoot and I'll handle the rest :)

To get even cuts make a loop region, use that to cut and just slide it along the T/L. Yes it's a lot of work, most things in this game are.

Or you could use a free scipt to insert markers at regular intervals.

Now I'm off to have a cold shower.

Bob.
liquid wrote on 1/6/2011, 5:56 PM
Lol...Ya, I watched the 18+ version too.......pretty dramatic.

Well I finally did get excalibur's strobe function figured out, but I think a lot of the cutting needs to be done manually, or at least tweaked to get that effect as not all of it is perfectly even the way a script does it.

On another but related note, one thing that disappoints me, and I'm not sure if this is just my computer or it's Vegas, is when I have one video track over another, and play the TL, the video isn't as smooth even if only one of the two videos are showing. To get it smooth I can only have one track, or the others must be muted. Same when I get this strobe effect, if I do short chops my computer it can't keep up. Too bad.
Chienworks wrote on 1/6/2011, 6:41 PM
That's what RAM prerendering is for. Use it. A lot.

I'd do the strobe by making a short video of alternating black white frames as an independent project, then importing this into the main project and using it as a mask track. B&W flashing frames on track 1 looped out as long as necessary, one video on track 2, other video on track 3. Set the compositing mode on track one to Mask Multiply (add the mask generator to track one depending on which version of Vegas you have). Wherever the 'flashy' track is white you'll see track 2; wherever it's black you'll see track 3.

Disable resampling on the B&W flashy video and ctrl-stretch/squish it to change the speed of the strobe.
john_dennis wrote on 1/6/2011, 7:02 PM
" I'm not sure if this is just my computer or it's Vegas, is when I have one video track over another, and play the TL, the video isn't as smooth even if only one of the two videos are showing. "

Update your system specs in your profile and you'll get more comments on how effective your system should be playing multiple tracks.
TheHappyFriar wrote on 1/6/2011, 7:53 PM
Put one video on track 1, another on track 2. On track one apply the Excal strobe effect: 00:00:00:xx on & off. XX = the # of frames you want on & off.
jetdv wrote on 1/7/2011, 7:04 AM
Excalibur should give you an exact number of frames on and off as per your settings. It should be exactly consistent giving you a perfectly smooth strobe effect.
liquid wrote on 1/7/2011, 11:18 AM
shift + b, ram preview, my new best friend. The strobe effect they used in that video is actually quite easy to do. Man, so much of whats done on a professional level can be done in Vegas. What a joy.
rs170a wrote on 1/7/2011, 11:31 AM
Man, so much of whats done on a professional level can be done in Vegas.

Now you know why it's called Vegas Pro.
:)

Mike
liquid wrote on 1/9/2011, 8:25 AM
Took the same song, a little bit of the same video, and tried my hand at this effect. I just downloaded all the footage from youtube, but all the edits are mine:-)

L8R wrote on 1/9/2011, 1:39 PM
wow... good job. Nice footage too.
Rosebud wrote on 1/9/2011, 1:55 PM
http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=21&MessageID=521466
farss wrote on 1/9/2011, 2:12 PM
If ever there was an example of "content is kind" that's it :)

I think what you're stobing between has a lot to do with how well it works. At first I thought the original video had single frames of white inserted at the cut to really push the strobe but then I realised (I think) it's because they're cutting between a dark and bright image.

Bob.
ushere wrote on 1/9/2011, 2:52 PM
to paraphrase bob:

if ever there was an example of.....

style over substance.....
farss wrote on 1/9/2011, 3:01 PM
"style over substance..... "

I found the "substance" quite appealing in a red blooded Aussie kind of way.

Bob.
ushere wrote on 1/9/2011, 3:14 PM
no doubt about that bob!!!!!