Hola... en base al script clarity creation posteado por xinelo, lo he modificado un poco y me quedo asi:

SetmtMode(5,4)
ffdshow_source()
SetmtMode(2)
SmoothLevels(preset="tv2pc",HQ=true)
#Denoiser
DeGrainMedian(limitY=6,limitUV=8,mode=3,interlaced =false)
#Algorithm I [Spline144]
dispWidth = 2560
dispHeight = 1440
mWidth = float(last.width)
mHeight = float(last.height)
ratio = (mWidth/mHeight)
newHeight= round((dispWidth/ratio)/8)*8
newHeight > dispHeight ? Eval("""
newHeight=dispHeight
newWidth=round((newHeight*ratio)/8)*8
""" ) : Eval("""
newWidth=dispWidth
""" )
Spline144Resize(newWidth,newHeight)
#Sharpen
LimitedSharpenFasterHC(strength=80)
#Algorithm II [Spline144]
dispWidth = 2880
dispHeight = 1620
mWidth = float(last.width)
mHeight = float(last.height)
ratio = (mWidth/mHeight)
newHeight= round((dispWidth/ratio)/8)*8
newHeight > dispHeight ? Eval("""
newHeight=dispHeight
newWidth=round((newHeight*ratio)/8)*8
""" ) : Eval("""
newWidth=dispWidth
""" )
Spline144Resize(newWidth,newHeight)
SetmtMode(1)
GetMTMode(false) > 0 ? distributor() : last

la verdad que es mucha la diferencia, se ve muy bien...