Comments

malowz wrote on 8/26/2012, 10:02 PM
its easier o do in vegas, using velocity envelope.

i don't know if avisynth can do this. probably need to do a manual "select range, set speed" various times.
Rv6tc wrote on 8/26/2012, 11:04 PM
Yeah, I've used velocity envelopes before, but I did a side by side comparision of the Virtual Dub version (via AVIsynth) and Vegas and there was no comparison on quality. So if I need a better slow motion, I always do it through AVIsynth. But I'm not good at all with scripts, so that's limiting.
malowz wrote on 8/27/2012, 12:39 AM
well, i believe the avisynth plugins to do slow where made for a constant speed, not "curve" or any other non-linear method. this may be a limiting factor.
fausseplanete wrote on 8/27/2012, 3:20 AM
Re-timing (&More) in AviSynth (&More):
http://blog.davidesp.com/archives/502
http://blog.davidesp.com/archives/496
Rv6tc wrote on 8/27/2012, 10:56 AM
Great.

Thank you, fausseplanete.
NickHope wrote on 8/27/2012, 8:21 PM
fausseplanete's first link contains mostly methods that I have cobbled together and are working well for me. But not of them include a provision for "ramping up" and "ramping down" the speed. That is something I would have to go and ask about on doom9.
Rory Cooper wrote on 8/28/2012, 6:39 AM
David last time we talked I ran a standard clip from Vegas uncompressed avi 100 frame and re imported and it looks smoother, do a few runs, can you confirm the same or not. I see a difference, not sure if it’s my eyes getting lazy but any conformation would be interesting.

fausseplanete wrote on 8/28/2012, 4:37 PM
Nick, absolutely, it's thanks to you that I found out about that particular technique, and my blog just provides links e.g. to your article. True the technique does not cover ramping, but by producing additional virtual frames in time, the consequent "excessive" pseudo-fps is a better position from which to apply velocity ramps in vegas. I've used that combination in the past e.g. when someone jerked their head round too quickly, I made it look more "natural".

Rory, I had a look at your YouTube video and the slomo looked good - as far as I can tell from a 360-lines video. I wasn't sure what I was supposed to be comparing though, as the two halves go at different speeds. So to "dig down" I downloaded your vid and loaded it into a matching vegas project, then played it at quarter-speed by moving that orange-brown "Rate"control slightly leftwards. Still wasn't sure, so I tried stepping (Alt-RightArrow) one frame at a time. Now I see the lower PIP only updates every other frame or sometimes every 2 frames. Naively one would expect that to look rougher, but I think it's hard to compare the overall smoothness (when played at normal speed) because the video is 25fps but my computer (like many) has a screen refresh rate of 60fps, consequently no 25fps videos play entirely smoothly... Also the image sizes of the PIPs in your video are maybe too small to reveal much difference (shrinking is a good way to hide many kinds of issues).
Rory Cooper wrote on 8/29/2012, 2:00 AM
Thanks David

Take any of your clips drop it on the timeline and render avi uncompressed_ default template_ custom_ type 100.000.
Import into Vegas, properties = 100 frame. Playback .5
Original clip also playback.5

Now compare the original 25 frame clip at .5 and the 100 frame clip .5 playback

This appears to work only with avi renders.

If the 100 frame clip is smoother this suggests Vegas was doing some tweening in the 100 f render
It appears to me that it is. I would be nice for someone to run some clips and give me some feedback if they get the same results or is it an optical illusion.

I used this method in the past and it worked for me except that I added supersampling on the bus track which I ass-umed was creating the smoother clip.

in connection with the ops post velocity ramping on 25/30 frame is not going to give good results but ramping on 100 frame is better. best results is ramping on 200 or 400 frame clips.