By the way,
[tom@localhost ~]$ diff <(grep surround41.conf /usr/share/alsa/cards/*.conf | cut -d ":" -f 1) <(grep surround50.conf /usr/share/alsa/cards/*.conf | cut -d ":" -f 1) [tom@localhost ~]$ diff <(grep surround41.conf /usr/share/alsa/cards/*.conf | cut -d ":" -f 1) <(grep surround21.conf /usr/share/alsa/cards/*.conf | cut -d ":" -f 1) 12d11 < /usr/share/alsa/cards/Echo_Echo3G.conf [tom@localhost ~]$
On 16 January 2016 at 22:09, Tom Yan tom.ty89@gmail.com wrote:
What I mean is, should we really by default set up PCMs that provide a SUBSET of POSSIBLE channel configurations that IS BUILT and RELYS ON ttable?
[tom@localhost ~]$ grep ttable /usr/share/alsa/pcm/surround* /usr/share/alsa/pcm/surround21.conf: ttable.0.FL 1 /usr/share/alsa/pcm/surround21.conf: ttable.1.FR 1 /usr/share/alsa/pcm/surround21.conf: ttable.2.LFE 1 /usr/share/alsa/pcm/surround41.conf: ttable.0.FL 1 /usr/share/alsa/pcm/surround41.conf: ttable.1.FR 1 /usr/share/alsa/pcm/surround41.conf: ttable.2.RL 1 /usr/share/alsa/pcm/surround41.conf: ttable.3.RR 1 /usr/share/alsa/pcm/surround41.conf: ttable.4.LFE 1 /usr/share/alsa/pcm/surround50.conf: ttable.0.FL 1 /usr/share/alsa/pcm/surround50.conf: ttable.1.FR 1 /usr/share/alsa/pcm/surround50.conf: ttable.2.RL 1 /usr/share/alsa/pcm/surround50.conf: ttable.3.RR 1 /usr/share/alsa/pcm/surround50.conf: ttable.4.FC 1
If we are really gonna provide them, why only these 3? What about: surround30 (surround51 - RL - RR - LFE) surround31 (surround51 - RL - RR) surround60 (surround71 - FC - LFE, corresponds to surround40) surround61 (surround71 - FC, corresponds to surround41) surround70 (surround71 - LFE, corresponds to surround 50)
surround30 more or less corresponds to surround50 as well, and surround31 doesn't even have the weirdness of using only either one channel in the C/Sub port like the others.