How to downmix 5.1 via AviSynth?

[dimzon]

How to downmix 5.1 via AviSynth?

to Stereo
to Dolby Prologic
to Dolby Prologic 2


Thanx!

[scharfis_brain]

look at my blog
http://md2.boerde.de/scharfi/

[dimzon]

NicAc3Source("c:\test.ac3")
ffdshowAudio(options="ismixer=1,mixerOut=1")

[dimzon]

look at my blog
http://md2.boerde.de/scharfi/
WOW! Great thanx! Just copy to main thread


http://md2.boerde.de/scharfi/wp-content/Quad.PNG
function quad(clip lf, clip rf, clip lb, clip rb)
{
Ltb=mixaudio(lb,rb,0.866,0.5)
Rtb=mixaudio(lb,rb,0.5,0.866).amplify(-1.0)

Lt=mixaudio(lf,Ltb)
Rt=mixaudio(rf,Rtb)

mergechannels(Lt,Rt)
}

http://md2.boerde.de/scharfi/wp-content/DPL.PNG
function dpl(clip lf, clip cf, clip rf, clip b)
{
Ltf=mixaudio(lf,cf,1,0.707)
Rtf=mixaudio(rf,cf,1,0.707)

Lt=mixaudio(Ltf,b.amplify(0.707))
Rt=mixaudio(Rtf,b.amplify(-0.707))

mergechannels(Lt,Rt)
}

http://md2.boerde.de/scharfi/wp-content/DPL2.PNG
function dpl2(clip lf, clip cf, clip rf, clip lb, clip rb)
{
Ltf=mixaudio(lf,cf,1,0.707)
Rtf=mixaudio(rf,cf,1,0.707)

Ltb=mixaudio(lb,rb,0.866,0.5)
Rtb=mixaudio(lb,rb,0.5,0.866).amplify(-1.0)

Lt=mixaudio(Ltf,Ltb)
Rt=mixaudio(Rtf,Rtb)

mergechannels(Lt,Rt)
}

http://md2.boerde.de/scharfi/wp-content/DPL2x.PNG
function dpl2x(clip lf, clip cf, clip rf, clip lb, clip cb, clip rb)
{
Ltf=mixaudio(lf,cf,1,0.707)
Rtf=mixaudio(rf,cf,1,0.707)

Ltb=mixaudio(mixaudio(lb,rb,0.866,0.5),cb)
Rtb=mixaudio(mixaudio(lb,rb,0.5,0.866),cb).amplify(-1.0)

Lt=mixaudio(Ltf,Ltb)
Rt=mixaudio(Rtf,Rtb)

mergechannels(Lt,Rt)
}


PS. Does clip cb in dpl2x mean LFE ???

[Wilbert]

Just stereo:

NicAc3Source("c:\test.ac3", downmix=2)

[dimzon]

Just stereo:

NicAc3Source("c:\test.ac3", downmix=2)

Does anybody know how 2 perform just stereo Downmix for ANY 5.1 material?
Thanx

[raquete]

look at my blog
http://md2.boerde.de/scharfi/ i saw last month in your page scharfis_brain,very cool.

@ all
why this good thread here stop? :(

[dimzon]

yet another method: http://forum.doom9.org/showthread.php?p=746891#post746891

a = last
f = GetChannel(a, 1, 2)
c = GetChannel(a, 3)
sl = GetChannel(a, 5)
sr = GetChannel(a, 6)
l = MixAudio(sl, sr, -0.2633, -0.1862) # -0.2247, -0.2247 for dpl I
l = MixAudio(l, c, 1.0, 0.228)
r = MixAudio(sl, sr, 0.1862, 0.2633) # 0.2247, 0.2247 for dpl I
r = MixAudio(r, c, 1.0, 0.228)
st = MergeChannels(l, r)
MixAudio(f, st, 0.3225, 1.0).Normalize()