8 Replies Latest reply on Aug 6, 2011 10:52 AM by Todd_Kopriva

    OpenGL no used to render composition to final film?

    Cheradenine

      First of all: English is not my first language, so I hope all of this will make sense to you. Also the AE I am using has a german UI.

       

      I am trying to use a computer at my universities lab to cut and reencode some footage with AE 5.5 (complete overkill, I know).

      I have one video in my composition, cut down to the relevant parts with no effects at all. Then I start a new "Create Film" render job (freely translated from the german UI) with the setting "use OpenGL-Renderer".

      render_settings.JPG

      Output module ("Ausgabemodul") is set to H.264.

       

      The OpenGL-Info in AE tells me everything is supported.

      OpenGL_info.JPG

       

       

      As soon as the render starts the info area tells me: "OpenGL not supported" and "Multiprocessor deactivated"

      openGL_not_supported.JPG

      The render/encode takes a rather long time.

       

      Also here are my Memory & Multiprocessor setting if these are relevant:

      multicpu.JPG

       

       

      So I guess my questions would be:

      1. Why is OpenGL not used in my case?
      2. Does OpenGL only work for effects, but not to speed up the encoder?
      3. If I really can't use OpenGL to speed up things, are there other ways to speed up encoding give the machine I have to work with?

       

      Thanks for taking the time to read this

        • 1. Re: OpenGL no used to render composition to final film?
          Mylenium Most Valuable Participant
          Why is OpenGL not used in my case?

           

          You are trying to use MP rendering and OpenGL together which cannot work as explained in the help.

           

          Does OpenGL only work for effects, but not to speed up the encoder?

             

            You are confusing the different kinds of hardware acceleration. OpenGL is used for raster oprations, which can include effecvts processing or 3D composition display, but not decoding or encoding footage. However, decoding is still hardware accelerated by ways of MediaCore as are some encoders such as H.264. Again, though, all this depends on specific render settings and what is invvolved in teh composition.

             

            If I really can't use OpenGL to speed up things, are there other ways to speed up encoding give the machine I have to work with?

             

            No, there is nothing you can do. In so many words: You are using the wrong tool and the whole workflow is just awful, leading to loss of quality. Due to how AE works and always fully decodes all footage to RGB data, you are not re-encoding, you are doing a full new encode. For what you possibly have in mind, Premiere Pro and Adobe Media Encoder would be more adequate.

             

            Mylenium

            1 person found this helpful
            • 2. Re: OpenGL no used to render composition to final film?
              Cheradenine Level 1

              Thanks fpr your swift and insightful reply Mylenium.

               

              You are using the wrong tool and the whole workflow is just awful, leading to loss of quality. Due to how AE works and always fully decodes all footage to RGB data, you are not re-encoding, you are doing a full new encode. For what you possibly have in mind, Premiere Pro and Adobe Media Encoder would be more adequate.

               

              I know AE is not the right tool for the work I want to do, but sadly it's the only tool available to me on this machine and I can only use this machine (due to my university being the usual kind of stupid).

              decoding is still hardware accelerated by ways of MediaCore as are some encoders such as H.264.

              So if I understand you correctly the graphics card is automatically used to speed up the encoding of any footage to H.264, independent of any OpenGL setting?

               

              On a sidenote: If I got this right, OpenGL would be used to speed up a raster operation like an effect in the comp, when I turn off MP rendering?

              • 3. Re: OpenGL no used to render composition to final film?
                Todd_Kopriva Level 8

                Mylenium didn't say this as bluntly as I expected him to, so I will:

                 

                Don't use the OpenGL renderer.

                 

                It's a preview renderer and not suitable for final output.

                1 person found this helpful
                • 4. Re: OpenGL no used to render composition to final film?
                  Cheradenine Level 1

                  Thank you for your clear words Todd. I understand now, that The OpenGL renderer should not be used for final output.

                   

                  Would you be so kind to answer my second question:

                   

                  Does the graphics card (ATI Radeon HD 5700 Series from what AE tells me) in any way speed up the encoding of H.264 in AE?

                  Or in other words: Does the installed graphics card matter at all in terms of video encoding speed?

                   

                  Mylenium wrote:

                  decoding is still hardware accelerated by ways of MediaCore as are some encoders such as H.264

                  That leads me to believe the encoding process to H.264 in After Effects is accelerated by having a strong graphics card.

                  If you could clarify this last point it would be really nice.

                   

                  Sorry to be such a nuisance, but the university personel is completely clueless in these matters and no help at all, so I have to come here to ask my questions.

                  • 5. Re: OpenGL no used to render composition to final film?
                    Todd_Kopriva Level 8

                    > Does the installed graphics card matter at all in terms of video encoding speed?

                     

                    There do exist some encoders and decoders that are GPU-accelerated, but none that are installed by default with After Effects.

                    • 6. Re: OpenGL no used to render composition to final film?
                      Todd_Kopriva Level 8

                      BTW, here's a video that I made to show all of the ways that the GPU is used by After Effects:


                      http://www.video2brain.com/en/videos-5359.htm

                      • 7. Re: OpenGL no used to render composition to final film?
                        Cheradenine Level 1

                        Thank you very much, all my questions are answered and now I can even educate the PC lab administrator about these thing.

                        I will suggest to him to look into getting additional encoders that are GPU-accelerated. Can these be aquired from Adobe, or from another software company?

                        • 8. Re: OpenGL no used to render composition to final film?
                          Todd_Kopriva Level 8

                          > I will suggest to him to look into getting additional encoders that are GPU-accelerated.

                           

                           

                          If you really think that's important. I don't see the need.

                           

                           

                          > Can these be aquired from Adobe, or from another software company?

                           

                           

                          Not from Adobe.