Hi Thomas, On 08/11/2011 11:33 PM, Thomas Martitz wrote: > Am 10.08.2011 13:11, schrieb Stefan Keller: >> Reviews, comments, testing etc. welcome, of course. > > I'm not a guy that uses benefits from resampling as all my music is > 44.1kHz, but I'd sure be willing to have better sound quality if possible. > > Did you check how much memory and cpu your resampler uses? Some targets > might get into trouble for some codecs and perhaps better off with the > simple linear one.
The memory footprint is roughly (15*256*2 + 90) * 4 Bytes. I.e. ~ 30KB. That could be reduced to ~15KB by calculating the sinc using fp_sincos in resampler_new_delta. As for cpu, the code does 15 multiplications and 30 additions (when downsampling) per output sample. Before implementing this, I asked on IRC whether that would be doable and the response was that it's doable although slowish on ARM. Anyway, the patch makes the sinc resampling a compilation option. It is only included if DSP_USE_SINC_RESAMPLING is defined. So for too slow / too low on memory targets we could just not define it. > /me wants to have a discussion as to whether we accept this and in which > form :) Yes, /me too. :) Best regards, Stefan -- Stefan Keller
