Permanent stuttering on any configuration of HW, Izzy, Settings, Codecs

  • Hallo Izzi Community,

    what i'm now describing is a problem since many older versions as well as at the actual one of Izzi.
    I never wrote it down here, as i thought it must be an Hardware/ Codec/ wrongly configured OS or Background Services because nobody else seams to experience this issue. But now it's urgent, as i need a smooth running clip by Thursday, and i can't find any real reason for it!
    The Problem is, i nearly always get some kind of stuttering. Sometimes the clip seams to stop some milliseconds in a distance of 3 or 4 seconds.
    Sometimes the video is stuttering like in a bad slomo and more likly as a Computer performance issu every few frames. But every stutter seems to be in clock.
    At the moment i'm working with a MacBook Pro 2013 with 2,7 GHz i7 CPU and 4 GB RAM.
    But this phenomena already appears with only one ordinary HD Video played with a projector actor and a Movieplayer actor only, H264 codec or ProRes files as well.
    Izzy can hold easily 50 frames but only sometimes if i freshly restarted the computer and Isadora, the Video is playing really smooth for a while, but changes back to stuttering pretty fast after loop.
    Footage is filmed by 1080/25p Streched to 1920x 1200 and pulled WUXGA/50MHz through a Datapath x4 splittet to 4 quarters.
    I Itried to optimize Izzy Settings and videocodecs as told by the Isadora "How to optimize for speed" post, but without any real chances or even changes.
    I do have this problem on different Computers; the same Macbooktype or older ones. Or on a 2008 Macbook Pro, even on a nearly new 2014 Mac Pro.
    Do you have any clou , what this might be?
  • Tech Staff


    Can you give us more information?

    • Does your computer have an SSD, what version of Isadora (and do you have a 2.x license)?

    • Do you strech the movie in Izzy or is it pre-edited?

    • Did you check if your Izzy framerate settings match the movie framerate?

    Best Michel

  • Hallo Michel,

    sorry, wrote these letters very late and weary.

    Yes the Macbook does have a SSD.
    I use the latest official Izzy Version 2.0.5 with 2.x upgrade license.

    I don't do nothing to the files but playing it with standard values in the Movie Player (speed 1).

    I tried different settings with the framerates. Content 25, Izzy 25; Content 25, Izzy 50; Content 50, Izzy 50.
    Nearly no difference...

    I found a solution now. Used PhotoJPG as Codec. Now it is very fluid with any settings!