ts-7000
[Top] [All Lists]

[ts-7000] Re: FFT very slow on TS-7260

To:
Subject: [ts-7000] Re: FFT very slow on TS-7260
From: "kurmannthomas" <>
Date: Fri, 30 Nov 2007 19:44:52 -0000
Thanks to all for their replies...
Does anyone know about an open source Fixed-Point FFT? Ive found one 
or two, but they only go upto 1024 points, which in my case would be 
10s of real data @ 100 Samples per second...not that much..I think 
the change to fixed point would be easiest for me since im a 
hardware guy and not specificly a linux prog. :(

Thanks alot
Best regards
Tom



--- In  "Daniel Serpell" 
<> wrote:
>
> Hi!
> 
> On Nov 30, 2007 6:36 AM, kurmannthomas <> wrote:
> >
> [...]
> > Im going to check with another floating point FFT next week to 
see if
> > its an FFTW3 problem, or really the TS-7260. My goal is to be 
able to
> > calculate (up to) 9 FFTs with (up to) 16384 points in less than 
1 or
> > 2 seconds...a DSP would have no problem with this...
> 
> I made some benchmarks on this board, using a mix of 50% 
multiplications,
> 50% additions, and I'm getting:
> 
> Double precision, emulated float:  0.23 mega-ops/second (~870 
cycles per op)
> Double precision, soft-float:  2.0 mega-ops/second (~104 cycles 
per op)
> Single precision, soft-float: 3.7 mega-ops/second (~54 cycles per 
op)
> 
> A split-radix FFT implementation uses 4N*log2(N)-6N+8 muls and 
adds,
> so an 16384 point FFT will take a total of 1.6*10^6 operations, 
50% muls
> and 50% adds.
> 
> So, using single-precision, soft-float, you should get about two 
FFTs per
> second, not counting filling the arrays, converting from int, etc.
> 
> I think you need a fixed-point implementation of the FFT.
> 
>     Daniel.
>




 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/ts-7000/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/ts-7000/join
    (Yahoo! ID required)

<*> To change settings via email:
     
    

<*> To unsubscribe from this group, send an email to:
    

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
 

<Prev in Thread] Current Thread [Next in Thread>
Admin

Disclaimer: Neither Andrew Taylor nor the University of NSW School of Computer and Engineering take any responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU