AE Render Backwards

[Boris2016]

Is it possible to make AE render an image sequence backwards? as in from last frame to first.

The idea being you can set another computer with identical files rendering forwards and they can meet in the middle.

[Mylenium]

No. And depending on the kind of effects used it would not be efficient to begin with. Temporal effects for instance may be dependent on previous frames existing just like particle systems and similar stuff will need to run their simulations in full.

Mylenium

[Martin_Ritter]

You can set up a second computer rendering the same comp. You must render the comp as PNG or TIFF or something like that and toggle the option to skip existing files. Your destination folder muss be accessible for both computers.

Also, you can set different rendering-ranges on both computers, but the first way is easier to do.

There is a plugin "BG Renderer" which will come in handy for this rendering workflow and I am also working on a render manager plugin for After Effects, which will come with a couple of useful features like parallelization, rendering presets and pipeline workflows. (But I guess I need till next year for a release - if you are interested you can write me an email at dev@vogelmoritz.de and I will notify you as soon as I have something).

Cheers,

Martin

[Terry Wayne Ranson]

yes. It is possible. Put your comp inside another comp, effectively turning it into a layer. Time reverse the layer and render. 

[Dave_LaRonde]

Boris2016  wrote

Is it possible to make AE render an image sequence backwards? as in from last frame to first.

The idea being you can set another computer with identical files rendering forwards and they can meet in the middle.

You can't do it with a simple "render backwards" command.  You have to jump through some hoops.

But I'd guess everyone's asking this  -- why on Earth would you want to do that?

[Boris2016]

some hoops?

As explained - The idea being you can set another computer with a clone hard drive rendering forwards and they can meet in the middle.

[Dave_LaRonde]

Oh.  Sorry.  Nope.  There are too many things in AE that rely on looking at the previous frames to create the current frame.  Trying to render out an image sequence in reverse order would result in a God-Awful mess if it could even be done at all.  Which it can't.

A nice idea, but there's no way on God's Green Earth it will work.

[Boris2016]

But thats not the case, AE can render single frames just fine - try it.

[Dave_LaRonde]

Heck, I know that.  And when you use the Save Frame As command, AE is indeed taking other frames into account to create that frame.

But Dude -- you can't force AE to render out an image sequence in reverse order.  Give it up.  Move on.  Life is too short for tilting at windmills.

[Boris2016]

So first off you said it was possible with but required 'some hoops' - you where wrong about that.

Then you stated AE can't render single frames - which you where also wrong about.

Then lastly you send a condescending response about life being to short.

Very helpful.

[P.M.B]

Maybe if you'd just explain wth you're hoping to achieve, someone could tell you how it could be done, Booo-ris.

Is it some big secret?  

[kirkeric]

Not even sure I understand the logic of this.  I understand what you said about meeting in the middle but just having two renders beginning at different points would achieve the same.

Eric

[Boris2016]

Allow me to explain, a sequence of 1000 frames, you set 'computer one'  to complete 0-500 and a 'computer two' to do 501-1000.

Problem is the second half of the sequence is really complex whilst the first half is simple.

You return in the morning and find computer one has long finished and computer two is just getting started. Hence setting computer one to start and 0 and computer two to start at 1000 and work backwards.

Whilst it seems it's not currently possible it would be an easy feature to introduce

PS - I hate forums everyone spends there time telling you why you're wrong to ask for something rather than answering the question.

[P.M.B]

Boris2016  wrote

PS - I hate forums everyone spends there time telling you why you're wrong to ask for something rather than answering the question.

Maybe you should spend less time on forums.    In case you failed to notice you never thanked anybody for even taking the time to try and answer your question.  Instead your complaining about how people tried to help you?  Really?  Look in a mirror buddy.  If you don't like answering other people's questions then maybe you should keep yours to yourself.

[Boris2016]

Fair point; I'm always very grateful to people who help on forums and solve problems. My point here is most of the responses have been people telling me I'm wrong to try this. Thats the bit that I don't like.

Kevin Hilt seems to be onto something when he says AE needs to render the previous frames in order to render the current so working backwards would be very inefficient. Might be something in that.

[P.M.B]

Maybe I'm being dumb but I don't understand why rendering from frame 1000 to frame 500 would be any faster than rendering from frame 500 to frame 1000?  Why would one be faster than the other?  This question is for anybody.

[Kevin Hilt]

If I understand correctly, imagine computer A is set to render 0-500 and computer B is set to render 501-1000. You hit start on both, and A finishes in 1 hour because those frames are easy, so it sits there doing nothing. After an hour, B is only on frame 750 because it hit some more intensive frames. If B was rendering from 1000-0 and A from 0-1000, A could continue rendering after hits 500 and both machines would continue working until they meet somewhere, say 600.

Again, rendering backwards is forcing a square peg through a round hole, but maybe you're looking less for efficiency and more for a solution where you hit the button, walk away for a long time, and are assured one computer never sits idle when there are still frames to render.

[P.M.B]

Thanks.  I think I see.  So it's not setting one computer to render 1-500 & the other to render 1000-501.  It's setting both to render the entire project, one forward & one backward until all frames are rendered.  So the computers would need to be running checks on each other every frame?  What about setting one computer to render all the even # frames and the other to render all the odd?  Shouldn't that in theory take them both the same amount of time? That way neither rig will be idle.

[Kevin Hilt]

That's a clever solution. It should only fail if, for example, even frames were mostly easy and odd frames were mostly hard, which seems like an unlikely edge case.

[P.M.B]

Nevermind I see why the even odd idea wouldnt't work.  That would only work for an image sequence which would need to be rerendered anyway

[Boris2016]

Gutter-Fish  wrote

Nevermind I see why the even odd idea wouldnt't work.  That would only work for an image sequence which would need to be rerendered anyway

Odd even would also work? is this easy to do?

[P.M.B]

Boris2016  wrote

Odd even would also work? is this easy to do?

I wouldn't know how to do it, not in after effects anyway.  But It seems like in theory at least it would be simpler than doing one backwards and having both computers to run checks every frame.  But Like I said it creates the temporal dependency issue on every single frame rather than just the one going backwards. 

[Rick Gerard]

Network rendering to an image sequence is I think what you want to do. Each machine starts to render a frame but the previous rendered frames are checked so no duplicate efforts are being made. The end result is what you want, you just have to set up the network and cue the work properly.

[P.M.B]

The odd/even idea would also create the "previous frame" dependency issue on both renders rather than just the one going backwards.

[r0nh0nn]

Yeah, this should be a no-brainer item for Adobe.  I used Lightwave 3D decades ago and it had the 'render in reverse order' feature.  For people that don't have a render farm at their disposal, this should be available.