On Sat, Nov 19, 2011 at 04:11:42PM +0100, Julien Claassen wrote: > I tried a few calculations to filter out the last channel > or isolate on of th3e other two channels, but no luck. I end up with > always having the third channel somewhere in the equation. No surprise. You can't mix 3 (or more) signals into 2 and recover them independently. To decoded your CD to surround you need a Dolby Prologic II decoder which consists of two parts: * A matrix recovering the missing channels (with lots of crosstalk from the others, but things are done in a way as to make this acceptable), * 'Logic' which detects the dominant sound directions and modifies the matrix to optimise for that. So in a movie you could e.g. have a gunshot or explosion coming only from the left surround speaker (most other sound would be pulled to that direction as well). This part is pretty useless for music. Jconvolver could easily do the matrix part. How the logic part is supposed to work exactly isn't described in any open documents AFAIK. For a music CD the surround channels would probably contain just room ambience and reverb. These are present in the stereo signals as well, at a lower level (as required for stereo) and mostly out of phase. The center channel is panned halfway between L and R by the encoding, there is no need to decode it except for film dialogue. So you can just listen to this in stereo and not miss anything. -- FA Vor uns liegt ein weites Tal, die Sonne scheint - ein Glitzerstrahl. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
