SmoothCam is smooth, but slow

By S Simmons. Filed in Editing, Final Cut Pro, Final Cut Studio  |  
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Does that say 14 hours?


Yessssssssssssssssssss it does.

There’s a great thread at the Apple support forums called the SmoothCam dirty little secret about the massively huge analysis times for the magic camera stabilization tool in Final Cut Pro 6 known as SmoothCam. Yep, they are quite large. According to the FCP 6 user manual this is how SmoothCam works:

Unlike other filters in Final Cut Pro, the SmoothCam filter must analyze a clip’s entire
media file before the effect can be rendered or played in real time. Using the
SmoothCam filter requires two independent phases:
Motion analysis: Pixels in successive frames are analyzed to determine the direction of
camera movement. Analysis data is stored on disk for use when calculating the effect.
Motion compensation: During rendering or real-time playback, the SmoothCam filter
uses the motion analysis data to apply a four-corner transformation to each frame,
compensating for camera movement.

It is indeed a 2 step process and that first step is a biggie. The manual suggests using a Quicktime Reference file to cut down on the huge analysis time. Do you really need to do that? I ran a little test on some HDV footage with my dual 2.7 G5 and here are the results.

I took a 1 minute and 35 second (01:35:26 to be exact) shot that is its own individual Quicktime file and edited a 12 second 26 frame shot into a sequence. I then exported that same 12:26 shot to a Quicktime Reference file as suggested in Chapter 22 of the manual, Using the SmoothCam Filter. The result? The near 13 second Quicktime reference clip nearly an hour to analyze:

smoothcam_53minutes.png 13 Sec. self-contained masterclip – HDV

The other 13 second shot that was part of the original one and a half minute master clip, 5 hours:
smoothcam_5hrs.png 13 Sec. clip part of 1.5 minute masterclip – HDV

After setting up this little test I read another test that suggested the huge analysis times might be a result of the HDV codec and its mpeg/i frame existence. So I then exported these same clips using Apple’s ProRes 422 codec.

The 13 second self-contatined Quicktime in ProRes 422, around 36 minutes:

smoothcam_selx422_36min.png 13 Sec. self-contained masterclip – ProRes 422 (HQ)

The 13 second ProRes 422 cut that was still part of the original one and a half minute converted master clip:

smoothcam_422_5hrs.png 13 Sec. clip part of 1.5 minute masterclip – ProRes 422 (HQ)

A bit less time but not by much. HDV file sizes and data rates are quite small while the file sizes and data rates of the ProRes 422 (HQ) clips are very large. So just for comparison I exported the same clips as DV-NTSC to see the difference.

smoothcam_3min_dv.png 13 Sec. self-contained masterclip – DV

smoothcam_21min_dv.png 13 Sec. clip part of 1.5 minute masterclip – DV

So from the looks of this informal little test it seems as if the SmoothCam analysis speed has many factors that contributes to how fast or slow it can analyze a clip. HDV clips have low file size and data rates but the complicated i-frame compression seems to cause a lot more difficulty in analysis, kind of like conforming HDV for an output to tape. It’s a no-brainer that regular DV25 resolution would be fastest since it has small data rates and frame sizes. Just because we can, let’s try it with DVCPRO-HD 720 files:

smoothcam_14min_dvcpro.png 13 Sec. self-contained masterclip – DVCPRO-HD 720p60

smoothcam_hour_dvcpro.png 13 Sec. clip part of 1.5 minute masterclip – DVCPRO-HD 720p60

It makes sense that DVCPRO-HD 720 would be somewhere in the middle. What this tells me is to take the analysis time into consideration when using SmoothCam. If you can build that time into the edit it will produce amazing results. To see the “snake shot” before and after SmoothCam, or side by side, have a look at the H.264 Quicktime clips below:

snake shot WITH SmoothCam – 1.4 mb

snake shot WITHOUT SmoothCam – 2 mb

both snake shots SIDE BY SIDE – 2.6 mb

As you can see it works pretty well, kind of like the Steady Shot mode on a Sony camcorder. Of course all this can be avoided by just using a tripod!

16 comments to “SmoothCam is smooth, but slow”

  1. Comment by J. Curtis:

    The side-by-side is pretty impressive…if you’ve got the room/pixels for it to scale up to that size.

    I could see going through the trouble of all that if you had some very important motion tracking shots or detail pieces you ‘thought you had’. But it’s not practical for much else.

    Any mention on what speed increases are gained by using an Intel-based computer?

  2. Comment by Daniel:

    How would this compare against something like 2d3 Steadymove for After Effects? It’d be interesting to see a comparison between different stabilizing methods.

  3. Comment by editblog:

    I haven’t seen a report on how much faster the Intel-macs are with this SmoothCam, I would hope quite a bit. One post in the Apple forum using the Octo-machine still had some huge times. I think it’s just the nature of the effect.

    As for Steadymove or AE… don’t know, don’t have them. But I can compare it to Avid.

  4. Comment by Ajit:

    What kind of system are you on? The end result is solid. Excellent addition to FCP. I’d like to know how long it would take on an Avid.

    Thanks, excellent stuff.

  5. Comment by maartai:

    I have an avid media composer system and it completely blows away your finalcutpro system. But, consider fcs is 1300 and my system is around 40,000. That motion was pretty smooth. Save yourself the time and just use a tripod. anyone shooting an event were there must be a steadycam better use a tripod.
    Avid Rules. Hi I’m apple I’m Mr. creative because my rich mom bought me a Macpro and I own finalcutpro so there. Im steven speilberg now. Leave it to the pros. Everyone knows If you ever want a real job in the industry and you tell them you have used fcp for 4 years they will just laugh at you. FCP has nothing on avid. You guys are all under apples lies. Just watch apples nab thing on their website. How many major movies did you see in that real.( and thats supposed to make me want to waste my time with finalcutpro) Until apple can make an awesome media manager and allow multible editors onboard at one time they will never make an impact on the major film industry. Oh, and final cut server is a joke.They dont care how good their software is. They just want you to buy their computer. If sony vegas had the ability to allow multiple editors at one time it would be up near avid in an instant. The thing is apple is a computer company Avid is well Avid they make software and hardware for instant collaboration. Yeah it costa

  6. Comment by editblog:

    Wow maartai. That’s an interesting comment. Seems like you are not a FCP fan. The Avid vs. FCP is always one for lots of debate and everyone has an opinion. They are both great edits systems and I can argue the merits / de-merits of both as good as anyone so all I can say is you are right …. and wrong. Thanks for commenting as that’s what blog comments are all about!

  7. Comment by Philipe :):

    Hey Maartai!

    I can’t say you are wrong, but I think you lack a little bit of perspective and understanding of the industry and the reality of things out there…

    Most productions that are created, both in the creative-narrative and corporate-promo-advertising world, do not have nearly enough budget to rent 40 000$ editing rooms.

    Plus Apple users are not all kids whose parents have bought them a computer. You insult a lot of serious professionals by saying that.

    Furthermore, you are attacking the democratization of video making: how are people supposed to get started if, in the first place, they need at least a 40 000$ investment or need to get hired by a big company?

    Come on! Don’t be so frustrated: it’s a new era and the pie is more divided, however more people get to be creative and live off their passion!

    Cheers to all video makers out there, whatever your platform is!

  8. Comment by Karl:

    i started out on the AVID about 13 years ago and since then have been going back and forth between FCP and AVID depending on what the clients can afford.

    technically, AVID is tits. she’s solid, flexible, and broadcast industry standard more or less. tight, sexy EDLs and producers love to sound boss hissing into their cell phones “steven, deal with that idiot DP youself, i’m in the AVID suite and this is costing me $350 an hour, jerkface!”. or something silly like that.

    FCP is loose, funky in many areas, sloppy in the areas it’s not funky, unstable and sort of schizo. producers in the FCP room get more creative, buy me the best coffee and have muffled phone converstaions like “this render is taking forever, but i can’t believe how whe saved the footage that idiot DP gave us!”.

    AVID gigs pay more, but by and large I actually enjoy my FCP projects. How many talking head corporate rhetoric pieces can you slice on and AVID before going brain dead and not caring anymore? For me, not many. How many zombie themed library commercials, blaxplotation valet training videos and performance art inside kinetic installations can i work and still stay interested? About ten years so far…

    Comes down to personal preference, I think. AVID pays for my motorcycle and carbon fiber mountain bikes, but FCP makes me want to pedal fast and bunny hop into the suite.

    My 2.97 cents.


  9. Comment by editblog:

    Hey great comment Karl. That’s about the best I’ve ever seen when comparing Avid and FCP in a more free-flowing, abstrack kinda way. That’s almost worthy of a post on its own!

  10. Comment by Steven S.:

    FCP is setting a whole new revolution in post production. Your gonna love what apple does next…

  11. Comment by editblog:

    Steven, that’s kinda what this whole blog is about. So tell us … what’s gonna come next?

  12. Comment by Frank Perrotto:

    Re: Maartai

    So I guess David Fincher and Walter Murch are being laughed out of the industry… you’re a jack-ass, typical response from a tech-head nerd who thinks it’s the tools that make something great, not the people behind them. What was it that Coppola said? Oh, and Kubrick too – one day the so-called ‘professionalism’ of filmmaking will be squashed forever and it will be a real art form.

  13. Comment by alec:

    Everyone knows that story and passion are unimportant/completely irrelevant, Frank; You’re just not mature enough to understand.

  14. Comment by Tylor:

    Short story. Export a managed project without (or with small) handles and none of the fat. Smoothcam the shorter clips.

  15. Comment by S Simmons:

    Sure that’s one way to do it but that can take a LOT of extra work depending on how many clips you have to work with. Shorter story: Apple make smoothcam better and faster!

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