4 Replies Latest reply on May 7, 2011 5:57 AM by Rick Gerard

    Panning and scaling image stills - jerky playback

    ClayStudio34 Level 1

      when I render out a movie of my project that has still images that are

      panning and zooming the playback of those stills is a bit jerky

       

      How can get the motion so its smooth and does'nt stutter

       

      any help would be very helpfull

        • 1. Re: Panning and scaling image stills - jerky playback
          AtonMusic Level 2

          Make the movie smaller.

           

          I have a RAID system capable of copying 60GB in 3 minutes. Thus, steroid fast.

           

          But when I hit play on a 1080p movie that moves ALL pixels on the whole frame continuously then

          things start to get REALLY BAD.

           

          If I take those 1080p and live-scale the window down to 1/4 the size Playback becomes smooth as baby kitty.

           

          2011 and we are STILL so far behind in the video world when it comes to RT Playback of large and compressed files.

          • 2. Re: Panning and scaling image stills - jerky playback
            Rick Gerard Adobe Community Professional & MVP

            There are also critical panning speeds for images. 24P is especially vulnerable to this stroboscopic effect caused by the interaction between retinal retention, frame rate, and, in the case of computer displays, refresh rates. It's the same thing that makes wagon wheels on the stage coach appear to go backwards sometimes. The only solution is to change the pan speed or add a bunch of blur to mask it.

             

            If your computer is up to the data rate required by the codec and frame size, and the image is still juddering then you're in the world of wrong panning, or in the case of a credit roll, wrong roll speed. The only solution is to change the speed.

            • 3. Re: Panning and scaling image stills - jerky playback
              AtonMusic Level 2

              Rick Gerard wrote:

               

               

              If your computer is up to the data rate required by the codec and frame size, and the image is still juddering then you're in the world of wrong panning...

              Unfortunately that is not always the case...

               

              Below a scenario that has been driving my nuts, nuts :

               

              On ANY Mac when viewing in quicktime the following applies:

              (Before anyone is tempted to say 'But my Mac will play back 1080p' - mine TOO.... But NOT when moving 1080x1920 pixels

              over an extended amount of time!!!)

               

              1) Boot up you Mac

              2) Prior to launching ANY others apps, launch the quicktime player with the 1080p pan

              3) Use the Plus-Minus keys to set the QT window to half size.

              4) Hit play. Shot play wonderfully.

              5) Open Premiere Pro or After Effects and do an hour's worth of intensive work.

              7) Close all the adobe apps.

              8) Open the QT player and try step 3 and 4 again.

               

              On my Mac which is about as fast as they come... THAT movies which used to playback VERY smooth now looks as if

              someone is having an epileptic seizure !

               

              Do a restart and it all looks smooth again. Work an hour in the two a.m. apps or other apps for that matter and your are back

              epileptic seizures....

               

              No matter how much one would like his movies to playback on a computer..... As of today, I have yet to come accross

              a CPU capable of moving 1080x1920 pixels SMOOTHLY over an extended period of time.

               

              Hopefully, the future holds more for CPU-viewing of Video !!!

              • 4. Re: Panning and scaling image stills - jerky playback
                Rick Gerard Adobe Community Professional & MVP

                It's all about the data rate. I have a MacBook (not a MacBook Pro) with only 2GB ram and it's fully capable of playing back full rez HD footage encoded with the H.264 eicoded at 16 Mbit/s, but can't handle the camera original from a Canon DSLR at 42 Mbit/s. Interestingly enough, the same clip encoded to ProRez 422 at 92Mbit/s plays back just fine. 

                 

                Check the Movie Inspector windows. These are all the same clip at the same size while playing.

                dr1.png

                dr2.png

                dr3.png

                It's all about the data rate and the codec. We push HD content to a flat screen from BluRay disks (external USB player) using a Mac Mini with no problems at all. I also cut HD in FCP and PPro all the time that's sent to an external monitor at full rez and it plays back just fine.  It's not the frame size that's killing your playback, it's the data rate and codec.