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Re: problem about dsplib real fft

Started by Vasudev Nayak August 15, 2002
Hi James,
Try using unpacki before calling the cbrev as rifft
takes in real input.
VN
_________________
>
> Message: 2
> Date: Tue, 13 Aug 2002 12:37:56 -0000
> From: "jamesztyou" <>
> Subject: Q: problem about dsplib real fft
>
> I had searched the former msgs, but can not find
> answer. so I post a
> help message again.
> follow is the test code where FFTSZ is a const
> integer 256, noscale
> defined as 0, scale defined as 1; and rfftws is an
> Uns array header,
> pointed to a 256 elements' Uns array, rfftws equals
> 0x1200(cording to
> myout.map), data are in Q15 format.
>
> //rfft
> cbrev( rfftws, rfftws, FFTSZ/2 );
> rfft ( rfftws, FFTSZ, noscale );
>
> //do actual processing.
>
> //rifft
> cbrev( rfftws, rfftws, FFTSZ/2 );
> rifft( rfftws, FFTSZ, scale );
>
> and here is the question, the result is quite
> different from the
> former datas... help..
__________________________________________________



thanks. now it works.

and I also find the example in the c5500 smaple directory.
but I wonder why ccs still use the out of date c5400 example.
...

--- In c54x@y..., Vasudev Nayak <vasudevns@y...> wrote:
> Hi James,
> Try using unpacki before calling the cbrev as rifft
> takes in real input.
> VN