[ANSWERED] Capture camera to Stage issue when playback

  • Hello,

    I am having some issues with Capture Camera To Stage. I basically did set up the stage as in this article https://support.troikatronix.com/support/solutions/articles/13000041633-using-capture-stage-and-camera-actors-to-create-new-media-files-

    So that the files automatically get replaced in the Video Files bin and can playback. When the video file go to playback it does what it looks to be a double speed playback, and then it freezes because it arrives at the end of the video, before the full length of the file is played. 

    Being this very weird, I tried using the camera of my laptop and the issue does not show up.

    I wonder if there is something related to the settings in the preferences or somewhere else I have to change in relationship to the camera I am using.

    While simply live-streaming with the camera through Isadora, there is no lag, and everything goes pretty smooth. 

    Could it be something related to the codec used to record the file? 

    Any help is appreciated.



  • Tech Staff


    I think you are correct in thinking that you need to change your 'Record Stage Setting' preferences. (found under the Output menu)
    The system offers all available DirectShow codecs, but only a few work well for use with Isadora. I have seen this double speed playback as one of the issues with some codecs.
    The problem of the file not playing to the end of the recording could be something else.
    How long of recorded files are you making? Since these videos are recorded in the Windows AVI format, there is a file sie limitation (4gb on most modern systems). This means that longer files will be cut off. So it is possible that your video is simply not being recorded fully.
    If this is the case, changing your codec settings to a smaller size (resolution) and/or lower quality will allow you to record longer segments before hitting this file size limitation.

    This is a list of known working/not working codecs (note some working codecs in this list may playback at double speed as you have seen).

    Known Bad Codecs:

    • Decklink MJPEG Compressor
    • Microsoft RLE
    • Microsoft YUV
    • Toshiba YUV

    Known Working Codecs:

    • DV video encoder (DS)
    • Hap (vfw)
    • HapA (vfw)
    • HapQ (vfw)
    • Intel IYUV (vfw)
    • MJPEG Compressor (DS)
    • MSScreen 9 Encoder (DMO)
    • MS Video 1 (vfw)
    • WMVideo8 encoder (DMO)
    • WMVideo9 encoder (DMO)
    • Black Magic HD 8 bit 4:2:2
    • Black Magic 8 bit MJPEG
    • Black Magic 10 bit 4:4:4
    • Black Magic 10 bit 4:2:2

    I personally have had my best performance/usage with the Black Magic 8 bit MJPEG codec.
    If is not part of the Windows system but is installed along with the free Black Magic Desktop Video software.
    It is available here: https://www.blackmagicdesign.c...

    Some codec testing I did previously demostrated that there is a substantial difference between codecs. 
    The largest factor in realtime recording is the CPU overhead. 
    This chart shows what I recorded as CPU usage for each of my installed codecs.
    Lower CPU usage is generally better.


    CPU usage

    DV video encoder (DS)


    Hap (vfw)


    HapA (vfw)


    HapQ (vfw)


    Intel IYUV (vfw) * (color is inverted)


    MJPEG Compressor (DS)


    MSScreen 9 Encoder (DMO)


    MS Video 1 (vfw)


    WMVideo8 encoder (DMO)


    WMVideo9 encoder (DMO)


    Black Magic HD 8 bit 4:2:2


    Black Magic 8 bit MJPEG


    Black Magic 10 bit 4:4:4


    Black Magic 10 bit 4:2:2


    As you can see the Black Magic 8 bit codec has the lowest CPU overhead, and in general was more reliable than the others.

  • Thank you for this. I will try this codec. In general, even recording the stage I am seeing some issues, even though they are about triggering the recording, which for some reasons doesn't make the actual recording to start because when I go to stop it, it doesn't create the file -> ps. this is another issue though.

    I am using Isadora on Windows, so that might be related.

    I will try the 8bit codec and see if that helps.

    The recordings are literally 10s so they are not reaching the max file dimension.

    Thanks for the help, I will keep posted if that fixes it.


  • Tech Staff


    Yes, try the other codec and let me know how that goes.