Velocity Curve: how to determine new clip size?

bravof wrote on 6/4/2017, 2:16 PM

I struggle with the Velocity curve: let's suppose I have a 10 second clip. I apply a velocity clip: how do I know the exact new clip length?

Currently if I accelerate the clip with velocity the clip will show MORE images: the original clip is 10 seconds, let's suppose I double clip speed: the clip will now show 20 seconds of footage in 10 seconds. I don't want that. I want to show to orginal 10 seconds of footage but in only 5 seconds.

This is what happens correctly when I use CTRL to compress a clip speed but I like the flexibility of a velocity curve.

What I'm really looking for is something that would tell me that my original 10 second clip is now 6.83 seconds and so I would crop it to that length in the timeline. OR even better: that it would auto crop to that length.

Comments

john_dennis wrote on 6/4/2017, 2:43 PM

If you're talking about applying a Velocity Envelope to a clip, I think your understanding is not correct.

I placed a 10 second clip on the timeline and rendered it without any changes and it measured 10 s 10 ms. After applying a Velocity Envelope to the clip, the rendered clip length was still 10 s 10 ms.

The velocity envelope determines the progress through a portion of the timeline per unit time. It doesn't appear to change the length of what's on the timeline.

Control + dragging the end of the clip does change the length of the clip on the timeline. By changing the counter to Absolute Frames you can easily calculate the final clip length using the Control + Drag method. Even if you also apply a Velocity Envelope.

Former user wrote on 6/4/2017, 2:53 PM

The extra 5 seconds that you're seeing is it coming back on itself, its a repeat of the new 5 seconds that you want, the rest is redundant. To not show the redundant part, split the video/stills after 5 seconds and mute or delete.

If I shoot a slow-mo clip, 60s in length on the timeline, (PAL region 25fps=12 seconds) at 125fps and apply a 500% increase in velocity to bring it to normal 25fps speed then the point to split it at will be the original video clip duration divided by 5 from the start of the event, i.e. 12seconds from the start. So I now have a new 12 second event at normal speed, note that the velocity envelope can be auto set to ITS NORMAL, which is what it was shot at, 125fps. I mention this, just in case you weren't sufficiently confused already 😂

bravof wrote on 6/4/2017, 3:03 PM

Thanks for your answer but I am not making myself understood.

I have a 10s clip and I apply a random velocity envelope to that clip (let's suppose an acceleration). So now my clip duration SHOULD be shorter but it's not as on the timeline it's the same 10s duration so I get repeated images once my clip reached the end of its images..

How do I know how much to TRIM my clip so that I have all my images (in my random example, for instance the output would be 6.2s so I should trim 3.8s)

Former user wrote on 6/4/2017, 3:08 PM

If you are using a whole clip, you will have a little indent at the top of the timeline frame to indicate where the clip will repeat. You can trim to that. If you use a portion of a clip, then you have to do the math.

Former user wrote on 6/4/2017, 3:09 PM

Ok, if its a "random" change then before starting take a note of the very last frame on the event or the last still, assuming that all stills are different.

Then apply the random velocity envelope, move cursor from start along the timeline until you come upon the previously noted last frame or still, now your at the new end point.

Former user wrote on 6/4/2017, 3:16 PM

Thanks david-tu, never knew about the small indent on whole clip, simply magic!

Tim L wrote on 6/4/2017, 5:39 PM

If your desired event is just a small section of a longer clip, right click on the event on your timeline and select "Open in Trimmer". (Or, just open the original video file in the trimmer.) Now, in the trimmer, locate the beginning and ending points of what you want in your event, or any other "important" moments in your clip, and press "M" to set a marker at each point. When you set a marker in the trimmer (not on the timeline), it embeds a little marker in just that clip.

Now, back on the timeline, as you play with the Velocity envelope you will see the reference markers moving around -- you can see where the "end" of your clip will fall as you tweak the Velocity envelope. For example, you may want that point to fall right on a music beat, or match up with narration, etc.

Former user wrote on 6/4/2017, 7:03 PM

David-tu, in vp14 the indents are still there even with cutting some of the origional clip, maybe not in previous versions?

Tim L ... seriously excellent also😀. I notice the markers(s) are also there on the audio track, fixed position, nice.

A great tool, velocity envelope, with a lot of options, more than I had previously realised.

I noticed that holding down Ctrl key while mousing the envelope allows finer movement of it.

Richard Jones wrote on 6/5/2017, 4:43 AM

Holding down Ctrl while using any slider in Vegas will allow finer control. of the adjustment.

Richard

bravof wrote on 6/5/2017, 2:14 PM

If your desired event is just a small section of a longer clip, right click on the event on your timeline and select "Open in Trimmer". (Or, just open the original video file in the trimmer.) Now, in the trimmer, locate the beginning and ending points of what you want in your event, or any other "important" moments in your clip, and press "M" to set a marker at each point. When you set a marker in the trimmer (not on the timeline), it embeds a little marker in just that clip.

Now, back on the timeline, as you play with the Velocity envelope you will see the reference markers moving around -- you can see where the "end" of your clip will fall as you tweak the Velocity envelope. For example, you may want that point to fall right on a music beat, or match up with narration, etc.

PERFECT!

This was exactly what I needed! I always start trimming and deleting the original track. So following your advice, I simply need to open the trimmed content in the trimmer, mark the END point (no need to mark the start point) and then as I apply and modify my velocity envelope I see the marker change! So I can then trim in the main timeline perfectly, but also adjust when I change my velocity curve. I love this!!

Thanks!