Hi, There's a lot of memcpy/memmove going on in the FFT kernel which I suspect degrades performance quite a bit... This is partly because some platforms requires buffers to be aligned for SIMD to work and partly because DC is not normally centered (which is normally what you would like to see in a spektrum).
For ARM in particular the alignment requirements are less strict so that would get rid of at least one memcpy for that platform. For centering an FFT at DC there's a nice trick, you just rotate the input by pi, that is multiply by 1, -1, 1, -1... I suspect that would be quite a bit faster than two memcpy and should be available on all platforms. Has this been discussed on the list before? --Albin _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
