5.1 > b-format > 7.1

[Sycho]

I am a big diy'er, and i two dvd players with a 6channel(L,C,R,SL,SL,Sub) out and i want 7.1 without any "prologic homebrews", so does anyone know of the equations for a "vienna decoder", it converts 5.1 into b-format, so than i can get a more spacious sound environment and 7 channel sound

[specise_8472]

Originally posted by sycho
I am a big diy'er, and i two dvd players with a 6channel(L,C,R,SL,SL,Sub) out and i want 7.1 without any "prologic homebrews", so does anyone know of the equations for a "vienna decoder", it converts 5.1 into b-format, so than i can get a more spacious sound environment and 7 channel sound

How are you going to get 7.1 sound:confused:
AFAIK there are no readilly available 6.1/7.1 encoders out there for AC3/DTS?.
The only one I can find is Vagas Video AC3 encoder, which allows the ES flag to be set if you have Matrixed rear channels. And I have tested this and it works:D (The only drawback to Vagas is that usually the plugin hides the custom pages and the only way to get them back is to nuke the registry and re-enter the reg code again. Then wait several starts for it to screw up again).

I am working on a VST plugin to directly encode the original Left/Right stereo and the WXYZ from ambisoncs into straight 5.1/6.1 wave files. An offshoot of this is you can reverse this procedure to recreate the original L/R,WXYZ files back out. I will do a plugin to do this, and when ready if you could test this out to see if it works any good on commercial AC3/DTS files.
I am waiting for my provider to cough up some webspace for me. So I can post then somewhere when this happens:p (Could be in the new year).

[Sycho]

I don't need anything to encode into EX, got plenty of DVD's with Dolby Digital EX, what i need are the equations to convert 5.1 into b-format, simalar to this (for the outputs on a prologic decoder):

S = Left + Right
D = Left - Right
a = Width control, varying between 0 and 180°
j = 90° phase shift


W' = 0.250Centre + 0.177S - 0.5jSurround
X' = 0.467Centre + 0.165S + 0.5jSurround
Y' = 0.7D

does anyone know how to properly creat a ambisonics equations?

[Umma]

Sycho,

Is this the information (http://pcfarina.eng.unipr.it/Public/Papers/109-AES98.PDF) you're looking for?