STT Short Term Trend Bars

// Green Candle = buy opportunities
// Red Candle = sell opportunities
// By SimpleTrading Techniques
study(title="RSI Chart Bars",overlay = true, shorttitle="STT Short Term Trend Bars")
src = close, len = input(8, minval=1, title="Length")
up = rma(max(change(src), 0), len)
down = rma(-min(change(src), 0), len)
rsi = down == 0 ? 100 : up == 0 ? 0 : 100 - (100 / (1 + up / down))

//coloring method below

src1 = close, len1 = input(50, minval=1, title="UpLevel")
src2 = close, len2 = input(50, minval=1, title="DownLevel")
isup() => rsi > len1
isdown() => rsi < len2
barcolor(isup() ? green : isdown() ? red : na )