Is there a way to downscale the videoquality in thumbnail

Hey Guys,

quick quastion. Is there a way to downscale the qualtiy of the thumbnail?
The following options does nothing for me:

//    // The options can be used to override default thresholds of video thumbnail heights corresponding to
//    // the video quality levels used in the application. At the time of this writing the allowed levels are:
//    //     'low' - for the low quality level (180p at the time of this writing)
//    //     'standard' - for the medium quality level (360p)
//    //     'high' - for the high quality level (720p)
//    // The keys should be positive numbers which represent the minimal thumbnail height for the quality level.
//    //
//    // With the default config value below the application will use 'low' quality until the thumbnails are
//    // at least 360 pixels tall. If the thumbnail height reaches 720 pixels then the application will switch to
//    // the high quality.
//    minHeightForQualityLvl: {
//        360: 'standard',
//        720: 'high'

Many thanks in advance.

Best regards