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Black flash when video starts playing (case 2708)

  1. #1
    jarvis24 Blair Jarvis, Administrator

    Black flash when video starts playing (case 2708)

    [edited from support email]

    Whenever there is a video file in a trial, there seems to be a short black flash before the video displays. This flash does not occur when bitmaps are displayed. I couldn't find troubleshooting tips for this issue, the only item on 'flashing' relates to inter-trial breaks. If there was no way to eliminate it completely, could I at least make the flash match my light grey background colour? Do you have any indication as to what it means that the black flash seems to be associated with playing the video file itself?

  2. #2
    jarvis24 Blair Jarvis, Administrator
    I think what you are seeing is the background of the Windows MediaPlayer. It is possible that you could see the default black background as the WMP begins drawing the first frame of video. Normally, this is not an issue because the default background of DirectRT is black also. I just checked though and WMP does give you the option to change the colour of the background. Check this out in WMP:

    tools > options > performance > advanced > video border color > change

    In case it helps, this is a Windows XP machine running Windows Media Player 10.4019.

  3. #3
    Changing the background colour in the Windows Media Player helps to make the 'flash' less dramatic. However, a discontinuation is still visible between the previous display and the start of the video.

  4. #4
    jarvis24 Blair Jarvis, Administrator
    Is the remaining break black?

  5. #5
    Does anyone know what the flash signifies? Is the flash the start of the trial as recorded by DirectRT, or is there some lag between the start of the trial and the black flash?

  6. #6
    This could be the normal process of DirectRT clearing the stimuli from one trial and preparing the stimuli for the following trial; it happens whenever DirectRT moves from one row of the .csv input file to the next.