David Henningsson wrote: (sorry for hijacking the thread) > The current logic hard codes the port names of headphones, headset and headphone mic. I think there is one more functional requirement likely to appear in the future. Namely, at LCE 2013, we discussed a reimplementation of module-virtual-surround using IIR filters (that I still have to clean up before submission), and Tanu suggested that it should be activated by default for headphones, which, from my viewpoint, is reasonable. After that discussion, some complications appeared: * My desktop PC has a Gigabyte H87N-WIFI board that allows for headphones to be plugged into the front panel. However, the Streacom FC8 Evo case does not have the headphone jack on the front panel at all, so I have to plug them into the rear jack. As a result, PulseAudio does not recognize them as headphones. So, for the purpose of filter application, some way needs to exist to hint PulseAudio here that the thing currently plugged into the green rear jack is, in fact, headphones, and not, say, desktop speakers. Or to say that this HDMI output, ultimately, leads to headphones. This may also be relevant for disabling the echo cancellation, as it is useless for headphones anyway. * I also have a set of filter coefficients that produce "virtual headphone" effect from 2.0 laptop speakers, which, combined with the above filter, allows for much better downmixing of 5.1 audio for such speakers. The caveat is: this currently works only for 13" laptops. Other laptop sizes need different coefficients. So, in the very unlikely case if I clean up the coefficient-generation program for submission and if someone generates more coefficients for me, then we might need a rich vocabulary for "stereo" speakers: traditional properly-placed stereo speakers, 17" laptop, 13" laptop, 32" TV on a stand, 47" wall-mounted TV, and so on. But, as I said, it is much more likely that I will not submit this at all due to lack of time - so please don't take this as something to consider immediately. -- Alexander E. Patrakov
