I don't see any decimating or interpolating blocks. How can I make efficient decimating and interpolating FIR?
OK, so I saw another thread in this forum where it is stated that the whole design has to run at one rate. But I think high level algorithms such as Dolby Mobile use multirate so perhaps at present it requires custom code and regular users aren't given the tools to write their own?
What if the desired function is a multirate FIR where the input and output are at the same rate, but internally there is decimation and interpolation to increase run time performance and reduce memory usage? That can definitely be implemented but there is no library block for that and that's what I need. Apparently I can't build it from lower level building blocks due to the single rate limitation throughout the whole design.
Several of the SigmaDSPs have built in Source Rate Converters (ASRC) which would handle this nicely. The modules all operate at whatever known static rate you want, and the input and output can be at any async rate. In fact, this feature is pretty much required for systems using S/PDIF because the external rates are not always known.
The other thread that you saw is correct - the SigmaDSP does not support multi-rate processing. All of the blocks in a SigmaStudio design are set to run at a single sample rate.
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