1 Record or upload your video. 2  At the end of the video processing stage in the upload interface, you will see an option to choose a Custom thumbnail under the Video thumbnails section. 3  Go to your channel Video Manager. 4  Locate a video and click the Edit button. 5  Click the Custom thumbnail button and upload a thumbnail.
Median is the middle number of a given dataset (if itÃÂ­s odd) while average is a definition of arithmetic mean, which is the most oft-cited average. The value of median depends on the number of elements in a data set (odd or even) while average does not.
The median is the middle value in distribution when the values are arranged in ascending or descending order. The median divides the distribution in half (there are 50% of observations on either side of the median value). In a distribution with an odd number of observations, the median value is the middle value. 54, 54, 54, 55, 56, 57, 57, 58, 58, 60, 60. When the distribution has an even number of observations, the median value is the mean of the two middle values.