On Wed, Oct 18, 2006 at 11:12:32 +0100, Dan Mills wrote: > > --- Steve Harris <[EMAIL PROTECTED]> wrote: > > > > But that puts potentially expensive gain > > > calculations into the fast sr code, also I was > rather planning > > > on using the impulse used for the upsampler to > > >provide the band limiting for free. > > > > the gain calculations are relativly cheap, its > > converting those gain > > levels back into a gain coefficient on the output > > that's expensive (from > > what I remember). > > But all that can still be done at 44.1/48, it is only > the final sample multiplication that needs its inputs > band limited and thus potentially needs the upsampler.
It's not that simple. The gain coefficient is not calculated for every sample. > > I dont think a streaming resampler is more > > challenging than a correct one > > that runs on buffers. You just have to preserve > > state with every call, > > rather than at the buffer boundaries. > > But that breaks the ability to use the vectorisation > capability of modern compilers and besides the call > and return overhead will end up costing as much as the > convolution! The vectorisation point is right, but the call and return is taken care of by inlining in modern compilers, it's quite cheap. - Steve