How To Calculate The Exact Placement
X = Video length (in sec.)
Y = X divided by 4 or X/4 (in sec.)
Y is the 1st thumbnail.
2 times Y or 2xY (in sec.) is the 2nd thumbnail (poster frame).
3 times Y or 3xY (in sec.) is the 3rd thumbnail.
For example :
x = 364 seconds (video length 6min 4 seconds)
y = 91 (364/4)
3rd = 3 x 91= 273
1 = 1min 31sec
2 = 3min 33
3 = 4.55min\
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