Can Prologic II be detected?

[Anonymous]

does anyone have the low down on the "encryption'' and how it works?

 

[Anonymous]

I'm confused Dolby Prologic II is a upsampling method of converting 2 audio channels to 5.1 channels(and happens to be pretty amazing at how well it works)?

 

[Guden Oden]

There are descriptions of how at least regular Dolby Prologic (dunno bout 2) at the HowStuffWorks website. It's not overly complicated really since it all takes place in the analog domain, it encodes the extra channels by phase-shifting them compared to one another and then extracts them by comparing the differences in one channel from the other. Basically.