Firstly I'd like to thank Triode for squeezelite. I had been trying to do some modifications to squeezeplay to add some audio post processing, but the complexity of the toolchain meant that I could never get it to build fully to a new image for my touch players; squeezelite have been a great alternative.
soundcheck wrote: > Hello Triode. > > Future considerations - just in case you'd feel getting kind of bored. > ;) > > > I'm wondering if it would be a huge effort to introduce stdout as > output. MPD has also done it. You'd just pass the ALSA stuff by and > create a stdout output device in device selection. > Maybe it requires an option to play with output buffer sizes. > > Background: > On a Linux system I could route squeezelite into brutefir to finally go > multichannel (active speakers) within a squeeze streaming environment. > I could also use local sox DSP etc. > > > Though the key issue I see is to work with different samplerates. I > wouldn't have a clue how to tell brutefir what samplerate/bitdepth is > coming from upstream (can slimproto communicate that?). > > This then might require resampling on the server. > > > Cheers I have been reading this thread and quietly working on adding my audio post processing. I have two additions to squeezelite which are running on an older version of Triode's code and I'm now incorporating them into Triode's latest code now it's stopped changing. The first is to add parametric EQs, these are configured in a txt file which squeezelite loads via the command line. These could be configured to be a graphic equalizer, but my aim it to use them with REW (http://www.hometheatershack.com/roomeq/) to reduce room modes in my listening room. The second addition is to change the volume control to add dither to the output when either filters are used or the volume is not 100%, this reduces the quantization noise which is introduced by truncating the data. The measurements so far from RightMark audio analyser show it's working as I intended. For both of the above I've had to get the data resolution, 16 or 24 bits and sample rate and recalculate the filters/dither on the fly as the tracks change. For FLAC and WAV which I use I've got the resolution fine, for the other codecs I can't find it in the header info so have had to assume 16bit, which is most likely for lossy media. I have dither and 4 PEQs running on my touch with no problems, the CPU load goes up as expected but not by too much. I'm not intending to use this for active crossovers at the moment, but it is a step in that direction, the PEQs could easily be replaced with crossover filters, but multiple outputs would be needed if all the processing was integrated into squeezelite. I'll post back with measurements and a copy of the code when it's finished. Unfortunately I don't get much time to work on it so it won't be as fast as Triode's developments, but I'd like to offer my changes back to the community once they're complete. Simon ------------------------------------------------------------------------ seroper's Profile: http://forums.slimdevices.com/member.php?userid=16239 View this thread: http://forums.slimdevices.com/showthread.php?t=97046 _______________________________________________ unix mailing list unix@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/unix
