How to spot banding in a video using vapoursynth?

[ACKR]

I am really poor at spotting banding in video i heard that using luma function of histogram helps but i can't understand on whether what i am seeing is banding or dither, would really like some advice on this

[Asmodian]

This is a good example of what you are looking for.
http://rationalqm.us/histogram.html