• Dear community

    I am running a very simple show where I play just 2 videos. They are encoded in mp4 and I do understand that this is not the ideal codec however my CPU load stays all the time below 2% so in that sense I have no load at all and it is just one video at a time. However the playing of the video is never smooth. It jumps and it stutters a lot of time. 

    Is there anyone of you experiencing the same problem and is there a way around this? I found some posts from 6 years ago but nothing recent in the forum.

    I would appreciate your responses. 


  • @jimmy-grima

    If you play back the videos outside of Isadora, using, for example, the OS's media player, do the videos stutter then?
    I ask as I'm wondering it it's an Isadora issue, or a media issue.
    Do you know how the MP4s were encoded? VBR or CBR? What the bitrate is? And what kind of drive are you playing them back from? Is it the same drive as the OS or do you have a separate media drive?

  • @mark_m 

    On a normal VLC or QuickTime or even Preview they do not stutter. 

     I do not have the encoding information. Do you have tips ?

     I have an SSD drive and it is the internal hard disk. I have 150GB of space available out of 256. 

    thanks a lot

  • @jimmy-grima
    I can't offer a solution but can make a suggestion: have a read of some of the help articles about performance optimisation:




  • Tech Staff


    Are you using Isadora 2 or 3? Have you set the external display to the same refresh rate as the frame rate of the movie? Mac or Windows?

    Best Michel