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  1. Member
    Join Date: May 2010
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    Hello

    Let's say I have a video on the timeline which is 20 seconds long. I add a velocity envelope of 50%, meaning that it will play at half speed. Meaning that 20 seconds will take 40 seconds to play. HOWEVER, it will really only play the first half, and the 2nd half is gone. This is because the video on the timeline is still only 20 seconds. What I would need to do is stretch the video to 40 seconds. Is there a way to automatically stretch the frame to an EXACT percentage (in this case 200%)?
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  2. Member
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    This isn't ideal, I still would like a way to TYPE a percentage increase for the stretch, but what it does, is as you stretch, it locks for a second at the appropriate length
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  3. Member
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    And another problem: If you split a video twice (so into 3 parts) and just slow down the middle part and stretch to that point, it does it based on the WHOLE VIDEO not just that 1/3 split
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  4. Member
    Join Date: Sep 2007
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    Another way, if you want 50% slow down , you can just right click the clip on the timeline =>properties => video even tab and enter the value in playback rate (e.g. 0.500) for 50%. To extend the clip , the only way I know is to drag the end, there will be a "notch" right where the doubling point is and it will "snap" to it. That notch is where the clip will repeat itself . Maybe others know a different way of extending the clip

    Not sure what you're saying about the last point about splitting a clip, are you saying the 1st third and last third are affected by speed changes as well? It seems to work ok here

    Vegas only has 2 methods of slo mo (assuming you don't have actual higher fps footage) , and that is to either blend frames or duplicate frames. Neither are ideal. The default behaviour with the clip (smart resample enabled) is to blend frames -> the new frames generated for slo mo are blended and blurry. If you disable resample, they are duplicated instead -> choppy playback. In all cases , having actual footage shot with higher fps is way better.
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  5. Member
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    Originally Posted by poisondeathray View Post
    If you want 50% slow down , you can just right click the clip on the timeline =>properties => video even tab and enter the value in playback rate (e.g. 0.500) for 50%. To extend the clip , the only way I know is to drag the end, there will be a "notch" right where the doubling point is and it will "snap" to it. That notch is where the clip will repeat itself (so a 25% playback will have a notch farther out). Maybe others know a different way of extending the clip

    Not sure what you're saying about the last point about splitting a clip, are you saying the 1st third and last third are affected by speed changes as well? It seems to work ok here

    Vegas only has 2 methods of slo mo (assuming you don't have actual higher fps footage) , and that is to either blend frames or duplicate frames. Neither are ideal. The default behaviour with the clip (smart resample enabled) is to blend frames -> the new frames generated for slo mo are blended and blurry. If you disable resample, they are duplicated instead -> choppy playback. In all cases , having actual footage shot with higher fps is way better.
    are there NLE with better slow mo options?
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  6. Member
    Join Date: Sep 2007
    Location: Canada
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    are there NLE with better slow mo options?
    assuming you mean generating in post (not shot at a higher fps in the first place) , the 3rd approach is to genereate new intermediate frames from motion interpolation. These new frames are a mix of the fwd and bwd frame (instead of blend or duplicating). You could do this in after effects (pixel motion) or with 3rd party plugins like twixtor , motion perfect, or even in avisynth for free. This method is much smoother, but lends itself to artifact generation, and is more CPU intensive (read=slow). Overall I would say the motion is better than blending or duplicating, but there can be some odd motion artifacts in some frames. Still, shooting a higher fps in the 1st place is still the best by far

    To illustrate the different approaches, I did a mini comparison a while back for another thread, a 4x slow down (so 25% playback rate), in vegas using the 2 methods, in AE's pixel motion, and avisynth's mflowfps. Have a look if you're interested. These are in Xvid, so you can use something like VLC or MPCHC to play them

    http://www.mediafire.com/?mkcnexhjewg
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  7. Member
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    Say I put a video on the timeline

    And split it twice

    Now I have 3 parts

    Part 1 I leave at regular speed

    Part 2 I make it play at 0.5, so twice as slow

    Then Part 3 regular speed

    I move Part 3 way over to the right temporarily

    Then I stretch part 2 so it plays the whole thing, but that snap point has it end at the end of the whole video, not at the end of just that part.. so when part 2 is done, part 3 is repeating part of it
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  8. Member
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    ok I see what you're saying. When I get a chance later I'll play with it and try to figure it out. I tend to do speed ramps in AE with time remapping . It's probably something really simple, hopefully someone else knows

    EDIT : Nope, seems to work fine here. I'm creating a subclip , it can go on the same timeline track, or a different one .
    So your 1 track is cut with "s" key into 3 pieces , the middle section you can right click, create subclip. Just put that into a new track for now. You can delete the "old" middle section . On the new subclip , Enter the 0.5 playback rate, strech it out to the notch exactly, then realign the last clip and it should play seamlessly .

    Maybe you weren't stretching the clip to the notch point? If you go over or under it will cut off or repeat frames
    Last edited by poisondeathray; 14th May 2010 at 14:45.
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  9. Member
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    Originally Posted by poisondeathray View Post
    ok I see what you're saying. When I get a chance later I'll play with it and try to figure it out. I tend to do speed ramps in AE with time remapping . It's probably something really simple, hopefully someone else knows

    EDIT : Nope, seems to work fine here. I'm creating a subclip , it can go on the same timeline track, or a different one .
    So your 1 track is cut with "s" key into 3 pieces , the middle section you can right click, create subclip. Just put that into a new track for now. You can delete the "old" middle section . On the new subclip , Enter the 0.5 playback rate, strech it out to the notch exactly, then realign the last clip and it should play seamlessly .

    Maybe you weren't stretching the clip to the notch point? If you go over or under it will cut off or repeat frames
    yes it worked

    thank you

    the ONLY thing I did differently was the "create subclip" can you explain what that does exactly? it didn't LOOK like it did anything
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