[linux-audio-dev] qjackctl port list

Fons Adriaensen fons.adriaensen at skynet.be
Sat Oct 9 21:48:10 UTC 2004

On Sat, Oct 09, 2004 at 10:03:11PM +0100, Rui Nuno Capela wrote:

> Florian's suggestion makes sense, of naming the ports like something in
> the lines of:
> out_1L
> out_1R
> out_2L
> out_2R

I tried a number of different schemes, and here are the results:

(creation order 1L, 1R, 2L, 2R, ....)

->  4L  3L  1L  2L  2R  4R  3R  1R         ????

->  out1L  out2L  out3L  out4L out1R  out2R  out3R  out4R

->  out_1L  out_2L  out_3L  out_4L  out_1R  out_2R  out_3R  out_4R

->  out_L1  out_L2  out_L3  out_L4  out_R1  out_R2  out_R3  out_R4

So none of them is really satisfactory, and this is only a simple case.
Things wil get worse for Ambisonics signals . For first order, the signals
are conventionally named W,X,Y,Z, in that order, and they need to be kept 
together, just as the components of an RGB signal. For second order B-format
which uses 9 channels, the names are even no longer in alphabetical order.

Since jackd seems to maintain the creation order at least for clients
that create their ports once and never modify them afterwards (it would
probably take extra code to change that :-), I feel qjackctl should at
least offer the option to keep them in that order.

For clients that add and remove ports while running, a special API to
jackd should be defined to allow them to specify grouping and ordering
of ports. None of this should depend on a viewer, as it just doesn't 
have the necessary info to get this right except maybe in some simple



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