Hi folks.<br><br>My first post over here.<br><br>While working on a music server optimzation (which ususally goes hand in hand with running pretty low buffers on realtime <br>streams) <br><br>I figured that certain HiRez flacs were causing XRUNS/hickups on my Linux server platform. <br>
The interesting thing is to run into XRUNS even though the stream gets send to a Squeezebox Touch which got <br>a 20s buffer on its receiving end. <br><br>However. Even a potentially short break of that flac decoding stream seems to cause a problem further downstream. <br>
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What to do!?!? I did this and that. Nothing worked.<br>
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I tested the integrity of those files. I also run them as .wav. That turned out to be OK.<br>
<br><br>I'm running flac 1.2.1 on a 64bit Ubuntu server btw..<br><br>The interesting thing is that not all flacs behave the same. Some are running smooth. Others skip. Which is reproduceable.<br><br><br>Than I found a thread discussion in the Squeezebox Server area about this very same subject. <br>
<br>The discussed solution solution was: RE-ENCODING to alias 0. Higher compression level seemed to <br>cause those hickups. Ok. It's not just me. <br><br>I wrote a batch script and re-encoded all those flacs to alias level 0.<br>
<br>However. The problem didn't go away in my (rather special) case.<br><br>If I'm running the offline decoded .wav of those 24/96 files I do not have <br>any problems. Hmmh. <br><br>Next. <br><br>I then looked up the flac formatting guide.<br>
<br>I figured that the encoding options used by the majority of applications are just the basic <br>aliases 0-8.<br><br>What struck me was that the flac formatting guide recommends higher (whatever) blocksizes in <br>case of >48khz HiRez files and also a residiual partition order of 2,2.<br>
<br><br>Since I do not have a lot of background about the internals of the decoder. I can't make much sense <br>out of the advanced features of the formating guide.<br><br><br>I'd really appreciate if somebody could tell me what best options to choose for encoding HiRez flacs.<br>
<br>My goal would be to achieve the most efficient realtime stream decoding. Probably I'd have to play with <br>blocksize and -r. <br><br><br>Another comment:<br>I'm wondering if the flac formatting guide shouldn't be updated with information related to HiRes <br>
data.<br>If the blocksize should be higher for Hirez as described in the guide there perhaps should be new <br>aliases for Hirez material. <br>I guess the majority out there is still using use those standard aliases which would apply for samplerates <= 48khz only.<br>
<br><br>Thx a lot.<br><br><br>Cheers<br>Klaus<br><br><br><br><br>