Helix MP3 on F4

jasonp4113 · ‎2014-09-17

Posted on September 17, 2014 at 09:55

Hi All,

Has anyone ported Helix MP3

floating

point to F4 to utilise the FPU?

If not, has anyone have a comment on the performance difference between the Helix fixed point and the floating point versions using the FPU in F4.

FYI: I am not converting one audio stream, but multiple and as fast as possible. I already know F4 is more than capable for at least one audio stream using fixed pt.

I just want to know if spending time converting MP3 fxt pt to floating pt for F4 is going to be worthwhile.

Thx Jason

waclawek.jan · ‎2014-09-17

Posted on September 17, 2014 at 11:13

I can't give you a specific answer, but note, that the floating point support in STM32F4xx is only for 32-bit (aka single-precision, binary32, ''float'' in C) floating-point variables rather than the more common 64-bit (double-precision, binary64, ''double'' in C) ones. Thus, ''double'' arithmetics is performed in software with no hardware support.

This usually comes as a surprise to many who come from the PC/''big embedded'' world.

JW