Subject: Re: [boost] Request to contribute boost::FFT
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2013-06-03 12:13:22
On 03/06/13 16:55, Pekka Seppänen wrote:
>
> As it could be, that you don't know until you have your PoC running that
> what kind of embedded platform you do need for your implementation to be
> feasible. Do you need a DSP chip, 16bit or 32bit, floating or fixed
> point or does a multi purpose micro controller cut it.
>
> And that's the point where you'd like stick your custom complex number
> class in; That tells you at what kind of level (as in how many bits)
> precision it operates and what kind of operations it makes. This is a
> bit what Matlab's Fixed Point toolbox does (I have used it a bit) but
> still I find a bit lacky for real life problems.
>
> I'd say that in the end you'll write your FFT completely by hand as
> that's where all the processing time counts. But! You don't want to
> start by doing yet another FFT implementation that is off-by-one bug
> etc. ridden for the first few days.
>
> As I'm not the one doing the implementation, please do regard this as a
> comment coming from the back row - easier said than done, that is. Just
> liked to share some thoughts on FFT matters that I've encountered during
> the years.
You can only test if precision is sufficient if you use exactly the same
code in your prototype and in your optimized version though.