Question for the DSP gurus: How hard would it be to implement an AC3 encoder as a LADSPA plugin that could be used in an ALSA config to encode stereo and 5.1 sources on the fly? Many Windows drivers seem to contain one, and it would be a nice response to the naysayers on LKML who doubt the power of ALSA.
It appears that a simple AC3 encoder is ~1500 lines of code: http://www.koders.com/c/fid04210C5E2BC83FC0BA5E0A2A1C37D52503E31EFD.aspx http://www.telos.de/Surround_Sound_Formats.360.0.html#1051 FWIW, when emu10k1/2 based cards first came out Creative claimed the DSP was powerful enough to do AC3 encoding on the fly, but, they never shipped an implementation - their drivers did it in software. One of their engineers said the DSP wasn't suited for the frequency domain processing required to encode AC3. Lee
