2016-03-28 4:42 GMT-03:00 Henrik Austad <henrik@xxxxxxxxx>: > On Sun, Mar 27, 2016 at 9:18 PM, Ricardo Biehl <rbpoficial@xxxxxxxxx> wrote: >> Hello guys! > > Hi Ricardo, > >> Sorry if this question is not part of the scope of this list. >> >> I'm developing a real-time microphone system that will work over local >> network using ALSA library and sockets API with IP (UDP/TCP support) >> <https://github.com/ricardobiehl/ipmic>. > > This looks like pure userspace, and going up to the level above, this > list is probably not the best place for it. Thank you, I'll avoid to write messages like this. > >> The purpose is to make a good replacement to traditional microphone >> systems (wired or wireless). >> The problem is that I found difficulties in network control and in >> ALSA library too :-) . > > Yes, I know :) :-) > >> Basically I need help to select the best network scheduler algorithm, >> set the right parameters, and (in audio) create a PCM plug which >> supports (1 channel * 16 bit sample * 22050 Hz) and BLOCKING opening >> mode. All this without quality loss and real-time. > > Theres a lot of details you gloss over here, that will eventually have > to be solved > > 1) how do you handle signalling (mic goes way, new one appears) > 2) what kind of equipment do you support? (one computer for each mic > gives you expensive mics) > 3) signal (time)correlation, you need some timestamping to the samples > to if you are going to combine local feedback > 4) Consistent alsa config across all endpoints These factors are really important, I'm going to thinking about! 1 -> In my current state I do not have signal handling yet. 1 -> Equipment is a detail which I'm very concerned, I thought smartphones is a good transmitter. :-) . 3 -> I think timestamping could be ignored right now in my current branch!? 4 -> ALSA conf files are one of the most important parts, because they are necessary to convert rate etc. > > What you need is network hardware, both in the NIC and in the network > infrastructure that can properly prioritize your streams and provide > accurate timestamps. It's ok. > > Have you looked at similar projects, like AES67 and TSN/AVB? > > AES67 is a best-effort approach, TSN requires support in the network > to prioritize the streams. Go and have a gander at OpenAVB [1] > >> Any contribution with the project is welcome! > > There may be something in the works that will be shipped out for RFC > soon (see [2]) > I haven't looked it yet, thanks! Thank you for reply! Big hug! > > 1) https://github.com/AVnu/Open-AVB > 2) http://mailman.alsa-project.org/pipermail/alsa-devel/2014-May/077087.html > > -- > Henrik Austad -- Ricardo Biehl Pasquali _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
