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Seamless loop in QuickTime Player impossible?
Hello everybody,
I have been reading the COW since a while and greatly appreciate all the help I gained through other peoples questions. Today I have a specific question I could not find any existing posts about:
Why does QuickTime (Player) add 1 frame to every video?
Most people wont really be bothered I guess, but if you need to loop a file seamlessly e.g. with a bunch of constantly moving logos you do notice..
I have created a little video in after effects that basically is a loop, the frames are numbered.
If you watch the frames below you see that there is the movement between 294 and 295, then no difference between frame 295 and 296 (296 was not even there in After Effects as you can see by the time code rendered in) and again the movement between 296 (which is the same than 295) and 000.Frame 294 (please notice Qt counting in the lower left and AfterEffects counting in the lower right..)
Frame 295 – the red thing moving as expected
Frame 296 – this frame was not there in After Effects as you can see by the burned in time code. Red thing NOT moving = same frame than 295 (causing the loop to stutter)
Frame 000 – the red thing moving as expected.
Watch the whole video if it helps 😉
YouTubeIm happy to provide the test file via skype etc. but I guess just about any quicktime file will do so see the “double frame”..
Any information about this “quicktime doubles frame” issue is appreciated!
Tobi -
9 Replies
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I agree with what Dave says and even if you wanted to edit in QT to multiply the loop you could just trim that frame off and save the clip like that- however my understanding is that you want to play that loop using QT. If that is the case, just use VLC or another player that does a better job of playing a loop.
Tudor “Ted” Jelescu
Senior Compositor/VFX Artist
Bucharest, Romania -
Hey there,
thanks for your reply.
Maybe I worded it the wrong way:
It’s not so much about sticking it together (thats a different story, but I’m usually happy to use FCP / AE etc. for that) the point is playback.
Although Im looking into “proper” playback options like PlaybackPro Plus from DTvideolabs and others often the only thing available is Quicktime (Pro if your are lucky ;).Now before you are all over me for playing out with Quicktime instead of a “proper” playout server: my background is data switching which involves 1080p50 via DVI (think Folsom Encore and such) – no conventional HD-SDI possible here. So the goal is to get the 1080p50 onto a Desktop via the GPU with 1920×1080 @ 50 Hz that is then further processed (via DVI).
Hope that helps for understanding the issue 😉
Tobi -
[Tobias Becker] “Why does QuickTime (Player) add 1 frame to every video?”
I can’t replicate the problem you’re seeing — I’m working on a piece of looping media now, and I’m not seeing any phantom frames directly out of AE like you are. Sometimes I get extra frames when I compress media to h264 — possibly because it needs to close a GOP — but I see that you’re working with ProRes media, so that shouldn’t be the issue here.
I’d do what Ted suggested and trim the bogus frames off of the file and save.
Also, make sure the Cache (hint) checkbox in Window > Show Movie Properties > Other Settings is checked; you can use it to force Quicktime to cache tracks in RAM to improve looping performance.
Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events -
I’ve found that Quicktime has to think, check its BlackBerry and call its mother before it goes back to the first frame of a loop. Accepting that, I’d take a page out of the DVD playbook and make a long QT movie that contains many (say, 10) copies of the clip butted up against each other so the viewer only see the pause once in every, say, 10 sightings of the clip, thus decreasing the odds that a viewer will see the hiccup, since most people will only watch it once or twice.
… I’m assuming.
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[Steve Roberts] “I’ve found that Quicktime has to think, check its BlackBerry and call its mother before it goes back to the first frame of a loop.”
Absolutely — that’s why hinting all the tracks in a looping movie is critical. I’ve also had success making RAM disks to play media from. Disk seek and access doesn’t get much faster than that!
Tobi, I saw you mentioned Playback Pro — it’s a great app, and I’d certainly prefer that for live playback over Quicktime Player.
Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events -
Thanks Tobi and Walter for mentioning Playback Pro — it looks terrific.
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[Steve Roberts] “Thanks Tobi and Walter for mentioning Playback Pro — it looks terrific.”
Steve, Playback Pro is fantastic. I work on a lot of live events, and we’re seeing PBP replace DDRs like the Grass Valley Turbo. It’s cheaper, faster, more reliable, and more flexible. If you do any live playback, it’s absolutely worth having in your toolkit.
Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events -
Hei,
I´m also trying to create a seamless loop, with video and audio. My audio ends and starts with a high volume. Playback Pro works, but cannot afford it at the moment. I´m testing the Ableton free trial, and it adds a black frame for the video and a pause for the audio. Can I avoid that extra frame somehow?
Best wishes
Kristine -
Hello all.
I see this is an older thread but found it looking for something else.
Anyway, after fighting this myself for a low cost digital signage app, I found a solution.
Create your videos in H264 as Quicktime .mov
download Media Player Classic
https://mpc-hc.org/
this player does seamless loops but only of quicktime, not sure why but it works.
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