http://bugs.winehq.org/show_bug.cgi?id=14717
--- Comment #230 from Alexander E. Patrakov patrakov@gmail.com 2011-11-11 02:52:02 CST --- (In reply to comment #228)
CPU usage is quite high (over 20%) for vlc especially when user mis-configure default sample rate to 96000Hz when the sound card only support 48000Hz
when normal usage is only 1% for vlc for playing 16bit 44100Hz
Yes, this is expected, and, I as already told, this is a necessary consequence of matching the default Windows resampling quality without MMX/SSE acceleration which I cannot implement anyway. That's why I still insist that, in the ideal world, resampling and mixing the sound should be left to the underlying platform libraries. If they are not good enough (as evidenced e.g. with the "ton of sliders" UI issue), we should talk to the authors of these libraries to make the API suitable for wine needs, not reinvent the wheel as I have done with my patch. However, that's a long-term plan.
You can tweak the constants in firgen.c to lower the CPU usage, but, of course, the resulting sound will be worse than in Windows. Try e.g. these values:
exp_width = 15.0
lobes_per_wing = 11
approx_bandwidth = 0.85
fir_step = 120 // does not affect CPU usage