Envelope Generator ++ connected to speed pauses media before jumping to new value

  • When I connect the envelope generator ++ to adjust the speed of a movie across time, the footage will visibly pause before jumping to the new value. I noticed that the thread from the movie player does turn red...suggesting that the signal stops momentarily. My current workaround to set the rate at 0 but I'd really like a gradual effect of footage speeding up/slowing down.

    When I connect the envelope generator ++ to intensity, the change is smooth. 
    Please see attached screenshot.
    p.s. I filed a bug report, and actually a couple for various things. Do people usually get a response within the next business day as advertised in the auto email response? I haven't at all...


  • @potatoe04

    if you look at the values from envelope generator you see that is kind of "0,1234". Every millisecond of at least 1/200 second you tell the movie player to adapt and change the speed this is really hard work for the movie player. As mentioned in some other threads the movie player is now "outside" of isadora and you have to be carefully how many values you send to this extra process.
    i would use a text formatter and strip the float to reasonable length
    secondly i would double-check that the video format and size and compression is compatible with the movie player and catches up with fast changes
    hope this helps
    best clemens

    51f9cc-screen-shot-2016-07-29-at-07.36.47.png 1cd988-screen-shot-2016-07-29-at-07.38.04.png

  • Izzy Guru


    What codec are you using?

    Best Michel

  • Dear @potatoe04,

    The most important thing you can do to improve performance is to ensure you are not using H264 or MP4 movie when attempting to adjust the speed like this. You should be using Apple Pro Res, Photo JPEG or HAP. All of these should respond the speed changes relatively well. You also may want to move to the advance beta version of v2.5 currently found at http://troikatronix.com/isa25beta - you may find that it performer better when attempting this.
    The other thing you can do is to put a MultiBlocker actor between the Envelope Generator and the Speed input. You can set the 'time' input to a value that limits the number of speed changes passing through the actor, and thus reducing the load on the speed change input. Start with a 'time' value of 0.05 and see if that helps.
    Best Wishes,

  • @mark,

    using the Multiblocker i always have the problem, that the last value is truncated, like in the picture attached