[mythtv] [mythtv-commits] Ticket #1104: multi channel audio support

Mark Spieth mark at dclabs.com.au
Sat Dec 22 01:46:19 UTC 2007

>  Sorry, again I have to correct myself. I now know what you mean with
> "rumble". With FILTERED_LFE defined I do have rumble (only with watching
> TV, mythvideo and mythmusic are fine). The problem I noticed before
> (without FILTERED_LFE defined) is more like an echo in LFE or like LFE is
> not playing the correct data. I don't know how to describe this further.
> This is just happening while watching TV. mythvideo and mythmusic are
> fine.

the LFE delay can be played with by changing the starting value of k2.
the latency is supposedly N/2 which is 4096 samples, however this may not be 
whilst it cant be more than N/2 it may be N/4.
Without filtering some parts of male voices gets through into the LFE as 
this simple
method just uses all the input.
somehow the sliding windowed add is adding the rumble in LFE_FILTERED mode, 
and is so bad that it cant currently be used.
I will do some research into this as I added it to pro_optimizer's code. 
There is not much doco on this and the original code was for windows as a 
foobar filter.


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