8 Replies Latest reply on Dec 8, 2014 9:45 AM by Szalam

    Applying an effect and rendering

    TinRobot44

      This is probably a very basic question, but I have imported a movie and applied an effect.  In this case, a plug in for removing flicker.  Having done so, when I play the movie, it runs very slow (and I have a very fast iMac).  When I edit using Final Cut Pro X, I know that adding an effect requires a moment for it to render.  Here, no rendering seems to happen and it just plays slowly.  What am I doing wrong?  How can I get the effect to render right away so that I can see if it is working or not.  With flicker removal, it's essential it runs at speed and in full quality to see if it's working.  I notice that if I turn the FX off, it still plays slow, but a green line appears over the area which has played and then that area plays at speed, but only with the FX turned off, otherwise, I'm not seeing it ever play at full speed.  The movie is HD pro res, but the way.

        • 1. Re: Applying an effect and rendering
          Mylenium Most Valuable Participant

          Well, straight to the point: You are mistaking AE for a video editing program, which it is not. It would seriously help to read the help files or watch at least some basic tutorials before blindly "jumping in".

           

          Getting started with After Effects (CS4, CS5, CS5.5, CS6, & CC) | After Effects region of interest

           

          Mylenium

          • 2. Re: Applying an effect and rendering
            Rick Gerard Adobe Community Professional & MVP

            This is typical problem for folks that don't read the manual. You preview in AE by performing a ram preview not by pressing the space bar. Ram previews are limited in length by the size of the composition, the resolution of the Comp Panel and the available resources. As Mylenium said, AE is not an editing program. It is designed to create shots or short sequences that are then edited into a movie in an editing program.

            • 3. Re: Applying an effect and rendering
              TinRobot44 Level 1

              No, not mistaking AE for an editing program at all. I totally know what AE does, but in this case, I am doing no editing, just applying a filter to a short clip and wanting to export.  How is that "mistaking for an editing program"?  Yes, I can read the manual in full to find out this one bit of information, but I was hoping someone here could help because my initial search for render and preview did not turn up the answer I was after, hence I am here.  Was hoping for some help or direction to where this info is in the online documentation, if that's possible.  Thanks.  (Having said that, thanks for the link to that blog article.  It looks helpful in the broad sense.)

              • 4. Re: Applying an effect and rendering
                bogiesan Level 4

                AE requires rendering, a video editor is usually built to do high speed previews. The green line is AE caching the rendered frames. Once the green line has stopped progressing, you can view the portion of your timeline that appears under the green line. The green line will be long or short depending on your preview settings and how much physical RAM you have on your machine. You must send the comp to the render que and then view the completed move in order to see it in total real time.

                RAM Preview is not done in the timeline. There's a window dedicated to RAM Preview. You will need the manual to understand the settings, probably.

                • 5. Re: Applying an effect and rendering
                  TinRobot44 Level 1

                  Yes, I see the Preview window, but it just doesn't seem to play in real time.  Maybe it's just not supposed to.  I have the most powerful iMac you can buy right now with 32GB ram.  The green progress bar on my 10 second clip never progresses.  I guess I am expecting it to work in a way that AE just doesn't.  It surprises me, but I guess you have to render the actual movie as an export to see how it looks, then make adjustments and do it again, but that seems a very surprising and inefficient workflow.   I can also see that some plugins will play quicker than others.  I am using a third party plugin and that might be part of the issue, but even the built in ones are slow.

                   

                  I was not looking to do anything fancy with AE, but just apply this one filter and output, but it requires choosing the settings and to do that, I really need to see the settings doing their job in, if not real time, something reasonable.

                  • 6. Re: Applying an effect and rendering
                    bogiesan Level 4

                    TinRobot44 wrote:

                     

                    Yes, I see the Preview window, but it just doesn't seem to play in real time.  Maybe it's just not supposed to.  I have the most powerful iMac you can buy right now with 32GB ram.  The green progress bar on my 10 second clip never progresses.  I guess I am expecting it to work in a way that AE just doesn't.  It surprises me, but I guess you have to render the actual movie as an export to see how it looks, then make adjustments and do it again, but that seems a very surprising and inefficient workflow.   I can also see that some plugins will play quicker than others.  I am using a third party plugin and that might be part of the issue, but even the built in ones are slow.

                     

                    I was not looking to do anything fancy with AE, but just apply this one filter and output, but it requires choosing the settings and to do that, I really need to see the settings doing their job in, if not real time, something reasonable.

                    This is a common misperception of new users. There are many ways to optimize AE's performance and to work in near realtime. But we've been successfully working within AE's limitations for 20 years. You must need to learn how it's done. You reduce the RAM Preview settings for quality and frames per second until you get something you can live with in terms of rendering speed and persistence of vision. You learn how to use the Region of Interest. You learn how to anticipate results. You learn how to do lo-rez proxies. You learn what sizes of media you can use effectively. You learn which filters are glacial and which are quick to preview. You lower your expectations until your working knowledge catches up with your dreams.

                    • 7. Re: Applying an effect and rendering
                      TinRobot44 Level 1

                      I love that answer.  Thank you.  My expectations are clearly based on my own expectations and not how the application works, but nowhere in the online tutorials or manuals is it going to say in plain English, "you can't see what you are working on very easily because it just doesn't work like that".  Now I know.  Big mystery to me is, why not?  Anyway, cheers for that.

                      • 8. Re: Applying an effect and rendering
                        Szalam Adobe Community Professional & MVP

                        TinRobot44 wrote:

                         

                          Big mystery to me is, why not? 

                        Because After Effects - at the core level -  is not like a video editing program. A video editing program plays back a video stream or several video streams. After Effects does not work with video streams that way. AE, like every other pixel-based compositor, works with a completely uncompressed frame which it then must render out before playback.

                        The resources on this page are a MUST for new AE users: Getting started with After Effects I know Mylenium already suggested it, but I want to reiterate the importance.

                        And, once you're done with that, this page will explain how to work better with AE: optimizing for performance: Adobe Premiere Pro and After Effects

                         

                        Here's a more detailed explanation from Rick Gerard of why AE doesn't do instant, real-time playback:

                        Sony Vegas, Premiere Pro, Final Cut, Avid are all NLE's (Non Linear Editors) and they are specifically designed to playback a video stream. With any of them, if you stack enough layers or effects on the video they will have to render a new video stream based on pixel based calculations for every pixel in the stack. This rendering, especially for HD sources or for complex plug-ins, will take quite a bit of time.

                         

                        After Effects, Flame, Fusion, Shake -- are all pixel based image processing applications that act very much like Photoshop. They calculate the values of every pixel in every frame, come up with a new pixel, and then play those pixels back as a video stream. More importantly, AE and all the other pixel based compositing apps, always work internally with completely uncompressed pixel data. NLE's rely on codecs and in some cases, hardware, to playback the video. It's an entirely different way of working with moving images.

                         

                        In After Effects you enable the preview by loading a bunch of frames into RAM then the video stream is played back. You start the process with the 0 key on the numeric keypad and not with the Space Bar as you do in nearly every NLE ever created. The length of the preview depends entirely on how much free ram you have available and it takes some time to generate these new pixels. The more layers, the more effects, the more calculations that need to be performed the longer it will take to process the RAM preview. There's currently no way around this rendering time. A modern NLE will handle an amazing number of video streams simultaneously, but as soon as you exceed the capability of the system you're stuck with a render. Most NLE's, given the same number of calculations, actually take a little longer than After Effects to do the same kind of effects. Open GL, and other GPU acceleration helps many NLE's achieve higher performance but it has yet to be implemented into a pixel based compositing app. The sad truth of the matter is that if you want to do compositing in any of the available compositing apps, you have to wait for renders. They are getting better. Memory management and efficiency is improving. GPU accelerated effects are being added, but for now, that's about as good as it gets.

                        I hope this helps. As long as you use After Effects to create shots and don't try to make it do the work of a NLE you should be fine. Movies come from NLE's, amazing shots come from AE.

                        - Rick Gerard