How to create fluid slow motion video

[Alsone]

Racer, whilst we're on the speed subject, how do you speed motion up?

Sorry if any of this is noob but I've never played around with speed before when editing and just as slow mo can make action look great, fast playback can help reduce the time spent watching a potentially boring bit of footage thats maybe still vital to the timeline.

For anyone not familair with its usuage, a good example of this used professionally is when you want to show a journey but don't want to bore people with the travel so you only show part of the journey and speed it up for the journey and then slow to normal when the road sign or landmark showing your destination appears. Result a long boring journey is reduced to only a few secs whilst still being inclusive to the story.

I'd like to know how to do this successfully.

[Lance Campeau]

Here is a small sample of a work in progress...

http://www.vimeo.com/756506

Please be sure to download the video in order to see the full quality.

Lance Campeau
www.LanceCampeau.com

[racer-x]

@Lance Campeau, That slow-mo clip looks good...........

Alsone wrote:

Racer, whilst we're on the speed subject, how do you speed motion up?

Speeding up is a lot easier than slowing down. Probably the easiest way to do it is in Virtualdub. Click FILE > FRAMERATE, then tick "Change framerate to". Enter the framerate you want. If you have for example 24 fps and want to speed it up 400%, just enter 96. Now tick "Convert to fps" and enter original framerate like in this screen shot:

[nzo]

Has anyone here used Twixtor for slomo? If so, how did you like the results?

[racer-x]

Yes, I've tested Twixtor and Gooder Video's MotionPerfect. They are both pretty good. Twixtor is around $500 US and MotionPerfect is around $50 US. In my tests, Both of those programs are very slow compared to Avisynth. The quality is about the same but Avisynth usually gives less artifacts. Avisynth is Free and much faster........

Plus, you can frameserve the Avisynth script directly into Premiere or Vegas timeline. No need to render out to large AVI like the other programs do..........

* Corection, I forgot that Twixtor can work within Premiere and After Effects, my bad..........

[qweret]

anybody have any suggestions in regards to how i might accomplish this on a mac?

i guess i could just read through the workflow and try to find the mac's substitution, but if anybody has any literal experience in these regards i'd greatly appreciate it.

[nzo]

Thanks Racer-X...interesting. At $500 for Twixtor I'll have to look into Avisynth

[Lance Campeau]

To Racer-X:

I have uploaded some more tests to my Vimeo page. Please download my new "snow" test video and have a look... you'll see that for footage using a static camera the frame kind of bounces a bit (like 1 pixel, plus/minus). You can see this effect because it has been slowed down quite a bit. You script for deinterlacing uses the "LeakKernelBob" filter...? I think that's what it's called... Do you think this pluging will help remove this bouncing effect? I have not had time to try it yet.

[racer-x]

I don't know what your script was.........did you output 24fps, or 30fps?

The specs on your FLV say 24 fps. I don't know if that's your source or Vimeo re-encoded:

Format : Flash Video
File size : 31.9 MiB
PlayTime : 2mn 42s
Bit rate : 1646 Kbps
StreamSize : 65.0 KiB
Tagged_Application : FlixEngineLinux_8.0.10.1 (www.on2.com)
Video
Codec : On2 VP6
PlayTime : 2mn 42s
Bit rate : 1643 Kbps
Width : 960 pixels
Height : 536 pixels
Display Aspect ratio : 16/9
Frame rate : 24.000 fps
Bits/(Pixel*Frame) : 0.130
StreamSize : 31.8 MiB

It looks as if frames were deleted or you have wrong field order, or you used "SeparateFields" comand. Use either:

AssumeTFF.Bob(height=480) # use what you want for height

Or use:

LeakKernelBob(1) # (0=BFF, 1=TFF)

[Lance Campeau]

Here is the script I used to deinterlace the original footage (avi 1440x1080 60i)

AVISource("Yourmovie.avi")
complementparity
separatefields

I know this may be part of the problem... But this is the only way I know how to convert a 29.97 NTSC stream into a smooth 60p stream (at the cost of half the vertical resolution). I picked up this script from www.100fps.com a few years while experimenting with standard DV footage.

[Lance Campeau]

AHHH!

Stupid me... I forgot an important step. I just reviewed the information on www.100fps.com... Now I remember why you mentioned the "bob" filter. I was using a different plugin for this... "Deinterlace - Smooth" from the website of Gunnar Thalin...

http://www.guthspot.se/video/

This plugin worked for standard DV footage but i have not tried it on HDV... once again could you give me a rundown on what plugin or script you would use... Maybe your script would be better?

Lance

[racer-x]

For all interested.........I'm posting a short clip demonstrating what you can expect to achieve with Avisynth. The 1st clip Normal Speed, the 2nd is 60 fps / 1/2 speed, the 3rd is 120 fps / 1/4 speed. The audio is also slowed down........

Slow Motion Test Clip (3.8 mb MOV/H.264)

60 fps script:

AviSource("yourclip.avi")
LeakKernelBob(1) # (0=BFF, 1=TFF)
assumefps(29.97)
TimeStretch(tempo=50)#(audio speed %)

120 fps script:

AviSource("yourclip.avi")
LeakKernelBob(1) # (0=BFF, 1=TFF)
smoothfps(120)
assumefps(29.97)
TimeStretch(tempo=25)#(audio speed %)
function smoothfps(clip source, float fps) {
fp=fps*100
backward_vec = source.MVAnalyse(isb = true, truemotion=true, pel=2, idx=1)
# we use explicit idx for more fast processing
forward_vec = source.MVAnalyse(isb = false, truemotion=true, pel=2, idx=1)
cropped = source.crop(4,4,-4,-4) # by half of block size 8
backward_vec2 = cropped.MVAnalyse(isb = true, truemotion=true, pel=2, idx=2)
forward_vec2 = cropped.MVAnalyse(isb = false, truemotion=true, pel=2, idx=2)
return source.MVFlowFps2(backward_vec,forward_vec,backwar d_vec2,forward_vec2,num=int(fp),den=100, idx=1,idx2=2)
}

[Lance Campeau]

Okay, here is the script I am using now... Thanks to Racer-X for the assistance. Be sure you have the MVtools plugin and the LeakKernelBob plugin installed in your AviSynth folder before running this or it will not work! Please use the photo diagram as a guide and feel free to experiment (try deleting a line or to and see what happens etc...) Please report back your findings. If you have further suggestions, don't hesitate to post them.

*IMPORTANT* I almost had a friggin' breakdown trying to figure out why VirtualDub kept crashing while rendering... It turns out that if you resize your video YOU MUST MAKE SURE YOUR DIMENSIONS ARE DIVISABLE BY 4,8,16 (you will have to experiment to find what works for you, for me, the magic number was 8) This problem set me back by several days and was extremely frustrating to deal with...

AVISource("untitled.avi")
ConvertToYV12
LeakKernelBob(1) # (0=BFF, 1=TFF)
complementparity
BilinearResize(960, 536)
AssumeFPS(24)#(gives 50% speed)
smoothfps(96)
assumefps(24)
function smoothfps(clip source, float fps) {
fp=fps*96
backward_vec = source.MVAnalyse(isb = true, truemotion=true, pel=2, idx=1)
# we use explicit idx for more fast processing
forward_vec = source.MVAnalyse(isb = false, truemotion=true, pel=2, idx=1)
cropped = source.crop(4,4,-4,-4) # by half of block size 8
backward_vec2 = cropped.MVAnalyse(isb = true, truemotion=true, pel=2, idx=2)
forward_vec2 = cropped.MVAnalyse(isb = false, truemotion=true, pel=2, idx=2)
return source.MVFlowFps2(backward_vec,forward_vec,backwar d_vec2,forward_vec2,num=int(fp),den=96, idx=1,idx2=2)}
Sharpen(0.50)

[Steph69]

Hi all please please help me with this, i love slo mo and the only script that worked for me was the very first post (thanks)

AVISource("HIGHSPEED.avi")
complementparity
separatefields

Works Fine.
-----------------------------
Every single script after that is a no go?

I have no clue about avisynth but long to get it working, i have just rebuilt my editing machine with a Quad core,4gig ram etc. etc.

Racer-x script always gives me an error with
"script error: There is no function named "leakkernelBob" line 2"

The script i used was

AviSource("d:\HIGHSPEED.avi")
LeakKernelBob(1) # (0=BFF, 1=TFF)
AssumeFPS(29.97)#(gives 50% speed)

Every other script with leakkernelbob wont work with the same error?

Iam working on PAL HDclips encoded to canopus HQ intermidiate files.

[exte]

Any slow motion work arounds for AVID users?

[Steph69]

Hi, i managed to fix it out, i had the wrong avisyth installed

Working now, so let the tests begin....

[racer-x]

Make sure that you download both LeakkernelDeint and MVtools filters. You can get them from HERE. Unzip them and put the DLL's of both filters in the Avisynth Plugins folder. If you don't do that, it won't work........


@ exte,
Anyone can use Avisynth as long as you have a PC. Feed the script to Virtualdub and save as an AVI that Avid can work with.

[alex4d]

If you want to do slow motion, shoot 1080i, even if your final project is going to be progressive. It is more important to have twice the samples per second than full vertical resolution.

Compressor is better than using the Clip Speed feature of Final Cut - if the footage is interlaced, FCP throws a field away first before doing any frame blending.

Export your clip as a QuickTime movie.

In Compressor...

If you want half-speed, in the Frame Controls tab, you only need use frame blending because Compressor turns each field into a frame:



If you want to slow down further, set the duration to be longer:



This will take a long time to compress, but should produce good results.

[alex4d]

Here's a video demonstrating FCP at half speed vs. Compressor half speed and quarter speed:

http://www.vimeo.com/776407

[racer-x]

I downloaded the original MOV to check frame by frame in virtualdub. Not too bad a job. Yes, The compressor did a much better job than the NLE. The NLE pretty much hosed it. The over all image quality became a bit softer, but very usable. About the only abnormalities I noticed was the Dude's zipper got all crazy when he walked off on the lower right. I'd say it did a good job over all, but the source was easy. People walk very slowly. Thanks for showing what a Mac can do..............

So far, I have yet to see anything besides a high speed camera beat Avisynth in a slow-motion test. Twixtor and MotionPerfect are right there, but Avisynth is free........

[Lance Campeau]

...you can frameserve the Avisynth script directly into Premiere or Vegas timeline. No need to render out to large AVI like the other programs do...

Hey Racer-X:

I am interested in learning how to to this... can you suggest a procedure or maybe a link?

[w.pasman]

(Sorry to all MAC users but this process was designed for PC...)

On apple, I think that Apple Motion (part of FCS) should do the job.
Check this tutorial:

http://www.apple.com/finalcutstudio/.../?movie=retime

Anyone who knows the quality of this as compared to AVSynth scripting?

[racer-x]

@ Lance Campeau,

In Premiere, just install the AVSplugin. That will let you import AVS scripts just like any other asset.

In Vegas, You need to use VFAPI to create a dummy avi out of the AVS script that Vegas can then open.

All NLE's really should support AVS, but sadly they don't. It's too bad, because that would make them much more productive. By loading up an AVS script, you can edit many more formats, like AVCHD, that might not be possible on it's own. You can also do real-time color correction and much more..........

Here is a LINK to a zip file that contains both tools for Premiere and Vegas. Read the Readme.txt for help........

[racer-x]

w.pasman wrote:

On apple, I think that Apple Motion (part of FCS) should do the job.
Check this tutorial:

http://www.apple.com/finalcutstudio/.../?movie=retime

That looks a lot like the Velocity envelops in Vegas. The only way to truly compare them is if they both worked on the same source clip and exported with the same parameters to the same format at the same resolution and bitrate.............

[alex4d]

Apple bought this technology when they acquired Nothing Real, the makers of Shake. The same technology went into Compressor and Motion.