<html>
<head>
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 10pt;
font-family:Tahoma
}
--></style>
</head>
<body class='hmmessage'><div dir='ltr'>
> - Mobile processors generally do NOT have good<br><div>> floating point power. Sometimes by a factor<br>> of 1000 flops.<br><br>It can be a factor of 1000 if the binaries are built assuming there is an FPU.<br>What happens is you get a system call for every failed float operation. If the<br>toolset is geared to understand that none is available then it generates soft<br>floating point operations that just occur in the user thread. Performance hit<br>is about two zeroes less than you are discussing here. Android appears to <br>generate softfloat code.<br><br>> - LADSPA and LV2 are built to process 32-bit<br>> floating point PCM data, and have no provision<br>> for processing 16-bit integer PCM data.<br><br>Do these systems actually process the floats though? I would have thought<br>most of their work was moving floating point *buffers around so that other<br>programs could do DSP work on them - these are plugin processors so there<br>is not a great demand that they manipulate the data they move between the<br>plugins (LADSPA is rather unfortunately named as in does seem to suggest<br>it does DSP which it doesn't - but I will happily stand corrected here). <br><br>Moving audio data around should only affect memory alloc rather than CPU <br>hits. If this code does floating point work then the basic stuff (mixing, <br>moving, etc) can be accelerated on the ARM FPU.<br><br>> So, trying to use LADSPA or LV2 in their current state will <br>> probably cause bottlenecks (either from doing FP math or <br>> from doing format convervsions to do integer math).<br>> <br>> Is this a Real Problem?<br><br>Yes, but I don't think it has to be that big. The bigger issue is why the hell<br>would you want to do it, integrate LV2 and LADSPA on to this platform?<br>The issue is that support on Linux is already patchy, so are the few apps <br>that support it on Linux likely to migrate to Android? A lot of the audio apps<br>that now appear on Andoid (very few of which come from a Linux heritage)<br>are taking a monolithic approach of having an integral package with the<br>synth/bass/drums/seq in the app.<br><br>There probably are arguments for doing this. The actual CPU performance<br>of the current ARM dual core handsets is pretty respectable and it is only<br>going to increase. So as the tablets start having these resources then there<br>are some interesting but I really think there is a difference between Linux<br>and something like Android - this just uses a Linux kernel, most of the rest<br>is way different.<br><br>Don't you think it is more likely that people who are interested will run<br>Linux as a replacement for Android on the ARM tablets rather than have<br>the apps ported over?<br><br>Regards, nick<br></div> </div></body>
</html>