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#1 Ulisses

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Posted 26 March 2012 - 09:27 PM

Hello,

I always produced videos for watchout in 29.97 or 30P, but now I have a video in 24fps.
In watchout preferences my display framerate was always set to 60, do I need to change any setting to play splitted video in 24 fps ?

Thanks,
Ulisses

#2 Mike Fahl

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Posted 27 March 2012 - 01:07 PM

The upcoming version 5.2 will allow you to set 24 fps as the rendering rate (assuming your graphics card and monitor support this framerate).

Alternatively, if all you videos are 24 fps, you could render at 3x24=72fps and your monitor adn graphics card supports this. Should work well with 24 fps video, since it's an even multiple.

Having said that, 24 fps will of course always tend to look a bit choppy for some kinds of content, due tot eh low framerate.

Mike

#3 Ulisses

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Posted 27 March 2012 - 07:31 PM

So the frame rate must be equal to refresh rate ?
I don't understand the relation of video frame rate x display refresh rate.

Now I'm a little nervous, because my finalcut timeline is 24P and I have to split it for 6 displays.

Thanks,
Ulisses

#4 Mike Fahl

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Posted 27 March 2012 - 10:49 PM

So the frame rate must be equal to refresh rate ?

No, it doesn't have to be. But keeping an even multiple generally result in smoother looking video.


I don't understand the relation of video frame rate x display refresh rate.

If the video plays at 25 fps (e.g. PAL video), it will look best if WATCHOUT render at 25, 50 or 75 fps. It will still work even if WATCHOUT renders at another framerate (e.g., 60 fps), but playback may be percieved as less smooth due to the mismatch of frequencies.

Mike

#5 Jonas Dannert

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Posted 28 March 2012 - 07:56 AM

And you will most certainly need an EDID Manager like DVI Parrot or similar on your Display output/s, in order to secure that your graphics card accepts the chosen (un-standard?) refresh rate in full-screen DirectX/Direct3D-mode.

/jonas

/jonas

#6 Fredrik Svahnberg

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Posted 28 March 2012 - 08:05 AM

Dear Ulisses!

Here is my take on this. It will hopefully make you less nervous :-)

• The frame rate of the video in WATCHOUT is important and below 50&60 fps you will undoubtedly see "stutter" in fast motion and pans etc.

• More important though is the video content itself. If your video does not have any super critical motion normal 25&30 (even 24) fps video will look just fine.

• If you do not have 50-60 "real" frames, i.e. 50 or 60 fps progressive video, your only option to achieve a perceived smoother playback is to apply something that is usually referred to as "frame blending" in post production (in AfterEffects or similar).

• Personally I would never set WATCHOUT to anything else but 50 or 60 fps (with the same setting on the graphic card). You can follow Mike's advise above to choose a refresh rate with an even multiple (50 for 25 fps and 60 for 30 fps etc) but please bear in mind that not all display devices are happy with 50 Hz. Also you should check the frame rate of the other video files in your show. So even if your video is 24, 25, 29,97 or 30 or higher, I would always set WATCHOUT to either 50 or 60 fps.

So here is the conclusion and quick advise for you.
1) Set WATCHOUT and graphic card to 60 or 50 depending o what display you have
2) Roll your 24 fps video and have a look Happy? All good then!
3) Not happy? Most likely you have to go back to post and try with frame blending or similar technique

Best regards,
Fredrik S

#7 Ulisses

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Posted 28 March 2012 - 04:44 PM

Thanks for all the advices!

I understand the stutters, but all of my videos were 30P (or 29.97) and stutters weren;t a big problem, sometimes I like the cinematic look :)

Another question (sorry, I can't test now), is it possible to run different frame rates in the same project/timeline ? I mean, one video at 24P, one 30P, and other video at 60P in same timeline ? Displays set to 60.

thanks again,
ulisses

#8 Fredrik Svahnberg

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Posted 28 March 2012 - 04:49 PM

Another question (sorry, I can't test now), is it possible to run different frame rates in the same project/timeline ? I mean, one video at 24P, one 30P, and other video at 60P in same timeline ? Displays set to 60.


Yes, you can. That was one the points with my response.

Best regards,
Fredrik S

#9 Brian

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Posted 13 April 2012 - 05:26 AM

You can run different rates... but you run into a conversion problem.

Google "3:2 pull down" for some more technical information but basically a 24p video has to have frames added or taken away as you convert to 30 or 60. If you're not working in PAL or SECAM I would avoid 50.

*if* you can hit 120hz (and that's a BIG *if*) then everything will be as smooth as possible. 120 = 24x5, 30x4, 60x2, so they all play smooth, no frames created from nothing... Unfortunately 120 is not typically understood except by newer 3D tv's that use the doubled refresh rate to display stereoscopic images. They use 240 too but we shouldn't even mention that lol!

You can definitely play mixed frame rates of video but you will always run the risk of stuttering as the 3:2 conversion is done someplace along the line.

When/if I have time to get my hands on content early I will use After Effects to transcode the 24p videos to 30 or 60 drop frame so it plays as close to WO native as possible. The less conversion WO has to do the better. The "frame blending" option does a great job of smoothing over the 3:2 pull down problems.

Brian