Real time playback?

[Steve Roberts]

AE has to render everything. Everything. It’s the price we pay for virtually unlimited layers and complex effects.

Apps such as Premiere only offer real-time playback for non-rendered sections of the timeline, and for some effects that have been coded to render quickly when used with the editing software. However, stack a couple of effects on a clip and you’ll start to see the limits of real-time playback in an editor. Heck (!) even big million-dollar compositors have to render … they just do it really fast.

Why can’t AE be coded to give real-time playback on a single-layer comp with no transforms, alpha or effects? Maybe it can, but I don’t see the point. If you’re only using one layer with no transforms, alpha or effects, why use AE?

In short, if you want real-time playback, use an editing app and limit your effects. If you want layers and fancy effects, use AE.

[Steve Roberts]

[Skeeter] “… or any MediaPlayer…?”

You can double-click on the footage in AE’s Project window to view the footage in the Quicktime Player in AE.

[Adolfo Rozenfeld]

Hello, Skeets.
You have every right to make this question!

Let’s see… the orthodox reply is: AE is NOT an editing application. Traditionally, the reason why an NLE can playback a clip in real time is very relatd to the fact the application is optimized in every way to do a particular format at a particular time. The timeline settings are all matching the clip’s settings: frame size, frame rate, codec, field order, etc. So, you coud say than when an NLE is able to play something in RT it’s discarding everything else 🙂

After Effects never worked that way. AE made at some point in its’ technological history a compromise between the greater flexibility in terms of image processing and having a moderately fast way of previewing things. AE compositions are not optimized for one specific format over any other, for example. Of course Comp settings have to match specific video standards, but that’s a different thing than how AE processes things internally.

However, with present day computers this “one format at a time” thing in NLEs is not true anymore. Some editing systems are now managing to offer multi-codec, multi-standard playback on the same timeline. And we can expect all other NLEs to match this functionality soon, given the highly competitive environment.

So in other words, whatever valid, historic reasons for AE not playing source material in real time are probably not valid anymore. And thus we are looking forward for AE to at least provide RT playback of source material in the way you describe. Let’s hope we get this in the future!

All the best!

Adolfo Rozenfeld
Buenos Aires – Argentina
https://www.adolforozenfeld.com
adolfo(AT)adolforozenfeld.com

[Adolfo Rozenfeld]

[Steve Roberts] “Why can’t AE be coded to give real-time playback on a single-layer comp with no transforms, alpha or effects? Maybe it can, but I don’t see the point. If you’re only using one layer with no transforms, alpha or effects, why use AE?”

So that you can easily and accurately trim footage before doing all the magic AE does 🙂
Again, a completely valid request. The reasons for the “compromise” are not probably not as valid today as they were in the 90s.

All the best!

Adolfo Rozenfeld
Buenos Aires – Argentina
https://www.adolforozenfeld.com
adolfo(AT)adolforozenfeld.com

[Derek Hader]

You’re Making lots of sense Adolfo, u read my Q accurately and gave me a great answer!

How about the Fast Previews button at the bottom of my Composition Monitor… what settings for Open GL, and adaptive resolution should I be using and why? Fast Previews Preferences… what should I have?

I’ve just been using the defaults that came with my AE7.

Any pointers are appreciated!

[Mylenium]

[Adolfo Rozenfeld] “However, with present day computers this “one format at a time” thing in NLEs is not true anymore. Some editing systems are now managing to offer multi-codec, multi-standard playback on the same timeline. And we can expect all other NLEs to match this functionality soon, given the highly competitive environment.

So in other words, whatever valid, historic reasons for AE not playing source material in real time are probably not valid anymore. And thus we are looking forward for AE to at least provide RT playback of source material in the way you describe. Let’s hope we get this in the future!”

Actually you are leaving one not so unimportant part out of the equation: It’s easier to optimize algorithms for fixed resolutions such as they are common to NLEs (HD is always HD in terms of pixel size) – if you know what you are going to use, you can optimize the hell out of every program, but even those multi-rez/multi-CoDec programs don’t work too well with large still images or “crooked” pixel dimensions in video files. In addition to that, in many cases at least one stream is played back relying on the video hardware, in most scenarios many more and only one tiny Quicktime or something is decoded by the CPUs. It is also a well-known fact that many of those systems still transcode parts of the footage to their native formats or use proxies. Of course they create those on the fly and often so fast, the user barely ever notices it, but nonetheless – it doesn’ actually make a fair comparison. I’m not saying that things could not be improved for AE as I’m also not happy that oftentimes things need to be rendered that should just stream and playback in realtime, but there will always be a difference between compositing apps and editing apps in terms of realtime feedback, no matter how much their function sets integrate similar tools in each program type.

Mylenium

[Pour Myl

[Steve Roberts]

Fair enough, Adolfo. With respect to digital applications, no limitation is permanent. 🙂

[Adolfo Rozenfeld]

We agree on pretty much everything, Mylenium. I only wish that some limited form of RT playback for unmodifed video footage could be there in the future. BTW, congratulations on the series of Mograph tutorials.
All the best.

Adolfo Rozenfeld
Buenos Aires – Argentina
https://www.adolforozenfeld.com
adolfo(AT)adolforozenfeld.com

[Erik Lindahl]

Then again, look at what Apple is doing with applications like Motion. This is in some ways a compositing, or animation app, that work A LOT more in realtime than After Effects. Sure, Motion won’t let me do everything that I can do in After Effects and it too will eventually bog my system down. But I reackon the main aspect of AE being “render always” is that it was written back in the late 1980’s/early 90’s where it’s approach was a must. Shake suffers in a similar way, when I reckon they shouldn’t need too.

Good this will probably happen in the future surrounding this… a Motion / AE / Shake “blend” would be a good blend of all worlds. The sad thing is that AE probably will require more or less a re-write to achieve true realtime performance.

[Adolfo Rozenfeld]

Erik: I really love Motion as a concept and all, but just to be fair, “real time” in Motion means something else. More like in a VJ application, it means “let’s play this at the highest possible frame rate”. This is not what “real time” means for a video application (you either have 24/25/29.97 fps in RT or you don’t). It won’t even display a red sign like AE does, because for Motion dropping frames is a frequent and legitimate option.
Now, the original poster didn’t mean real times effects. He meant real time playback of the raw video sources. I can imagine that happening at some point.
All the best!

Adolfo Rozenfeld
Buenos Aires – Argentina
https://www.adolforozenfeld.com
adolfo(AT)adolforozenfeld.com