11 Replies Latest reply: Dec 19, 2010 4:07 PM by JSS1138 RSS

    Memory / Mercury Playback Engine issues

    Paul Joy (UK) Community Member

      I've started work on a project in Premiere Pro today and I'm running into some problems that seem to be memory related. This project has around 30 mins of footage from two DSLR's (around 50 clips). The way I would normally work is to drag all of the clips into a sequence and then scan along the sequence choosing my favourite shots, this is normally a lot faster than selecting each clip in the project window.

       

      What's happening when I do this in Premiere is that after dragging all of the clips into a sequence Premiere seems to be loading the clips into memory (RAM) until it can't load any more. I have 16GB of RAM and premiere loads until it uses around 9GB of that, at which point everything becomes unresponsive, so unresponsive that I'm unable to drag though the sequence a browse the shots without big delays. Any dragging of the CTI after this point does not update the program monitor and I can only carry on by letting go of the mouse and waiting for Premiere to catch up / reload the next set of media into memory.

       

      I've tried this with both hardware accelerated MPE on and off and in this instance that doesn't seem to make any difference.

       

      Looking at my scratch disks they are not really being taxed that much when I drag through the sequence so it's not related to scratch disk speed, my CPU's are also barely registering any effort so it doesn't look like a bottleneck in the system at all. It feels like I'm having to wait while a new set of clips are loaded into memory and prepared for display.

       

      Is this just a limitation of the MPE when working with DSLR footage?

       

      I'm guessing the one answer will be to upgrade to more ram but at over £,3000 to go to 32GB I'm inclined not to do that if I can help it! I'm guessing working in a better codec would help too, I'll try that out and report back but it would take away the whole benefit of using the PP workflow.

       

      Any tips appreciated.

       

      Paul.

        • 1. Re: Memory / Mercury Playback Engine issues
          Andrey V Community Member

          Well very strange issue. I am also working with AVCHD and never had this problem with one layer of video ot 4 layers of the same video with color correction. At first did you try to take a look at the sequence settings and see if you selected correct preset?

          Second I would take a look at the hard drive ad see if it is not out of space, and defrag perhaps needs to be performed.

          To tell you the truth the amount of memory you have should not be a problem. It sound more like you have a HDD issue it is just simply does not have enough speed to transfer all the data. Or maybe you are using USB connected drive and that would slow things little bit but not that drastically, or maybe you are editing from a flash card? Then that would really drag its feet.

          • 2. Re: Memory / Mercury Playback Engine issues
            Paul Joy (UK) Community Member

            Thanks for the reply.

             

            The problem isn't with multiple layers of footage, it's with having multiple sequences with lots of footage (30 mins) on one layer. I have since confirmed that this only applies to my Canon EOS footage so I think it's to do with the MPE buffering limits. With footage converted to ProRes it doesn't happen, even with four times as much content.

             

            As far as my drives go, I'm using two 512GB SSD scratch disks which are each capable of delivering content at over 200 MB/s so that's not the issue.

             

            It's seems pretty clear after playing around with EOS footage vs ProRes that the MPE is buffering as much as it can into RAM in order to be able to transcode / display it on the fly. Dragging through long sequences to preview the footage it probably just too much for it as it then has to keep swapping the content it's buffering.

             

            It seems that for bigger sequences where you're likely to be quickly scrubbing around reviewing a wide range of material it's probably still best to transcode to an editing codec so that the MPE is not overloaded.

             

            Or at least that's my experience so far.

            • 3. Re: Memory / Mercury Playback Engine issues
              JSS1138 CommunityMVP
              MPE is buffering as much as it can into RAM in order to be able to transcode / display it on the fly.

               

              Hmmm.  I question that observation.  According to an Adobe employee, hardware MPE is not used to decode/encode anything.  It is used for some effects, scaling, deinterlacing and frame blending.  That's it.  It won't help with normal playback at all.

              • 4. Re: Memory / Mercury Playback Engine issues
                Andrey V Community Member

                I am not saying about scratch disk, I was mentionning the disk on which your media is located.

                • 5. Re: Memory / Mercury Playback Engine issues
                  Paul Joy (UK) Community Member

                  Hmmm.  I question that observation.  According to an Adobe employee, hardware MPE is not used to decode/encode anything.  It is used for some effects, scaling, deinterlacing and frame blending.  That's it.  It won't help with normal playback at all.

                   

                  I'm not so sure, I've been told it's the Mercury Playback Engine that's enabling the realtime playback of the Canon H.264 footage and is used to display all video codecs. Certainly enabling hardware support (CUDA) further enhances it's ability to play back EOS footage more smoothly, even without any effects.

                  • 6. Re: Memory / Mercury Playback Engine issues
                    Paul Joy (UK) Community Member

                    Andrey V wrote:

                     

                    I am not saying about scratch disk, I was mentionning the disk on which your media is located.

                     

                    The media is located on those disks. Drive access is not the issue.

                    • 7. Re: Memory / Mercury Playback Engine issues
                      JSS1138 CommunityMVP

                      I've been told it's the Mercury Playback Engine that's enabling the realtime playback of the Canon H.264 footage and is used to display all video codecs

                       

                      By whom?  Like I said, my information comes directly from an Adobe employee posting here in these forums.  Unless I misunderstood, hardware MPE is not used for any such thing with any footage.

                      • 8. Re: DSLR footage playback  / memory issues
                        Paul Joy (UK) Community Member

                         

                        By whom?  Like I said, my information comes directly from an Adobe employee posting here in these forums.  Unless I misunderstood, hardware MPE is not used for any such thing with any footage.

                         

                        Okay, maybe I misunderstood then as I thought that the MPE was basically responsible for all video playback in PP with GPU utilisation available for effects and rendering when required. Like I said at the start, enabling or disabling hardware MPE doesn't make any difference to this problem anyway.

                         

                        Whether it's the MPE, an H.264 encoder or some other underlying technology, loading a sequence with DSLR footage and scrubbing through it fills the RAM and then things get very laggy. There may not be a fix and I'm sorry if I blamed it on the MPE when apparently that has nothing to do with it.

                         

                        I've been so busy trying to solve issues with Premiere this week that my brain is a bit fried so I'll just leave it there

                        • 9. Re: DSLR footage playback  / memory issues
                          JSS1138 CommunityMVP
                          I thought that the MPE was basically responsible for all video playback in PP

                           

                          I won't say for sure you're wring about that.  If memory serves, the point made by the Adobe rep was concerning hardware acceleration which, as you noticed, makes no difference here.

                          • 10. Re: DSLR footage playback  / memory issues
                            Todd_Kopriva Adobe Employee

                            what is and isn't processed by CUDA (and how people keep misusing terms):

                            http://forums.adobe.com/message/3340537#3340537

                            • 11. Re: DSLR footage playback  / memory issues
                              JSS1138 CommunityMVP

                              Yep, that's the thread.