Jaime Andrés Aranguren Cardona wrote:
> "Jim Thomas" <[email protected]> escribió en el mensaje
> news:[email protected]..
>
>>Jaime Andrés Aranguren Cardona wrote:
>>
>>>What else could I try, guys? I'd really appreciate if you can take a
>
> look at
>
>>>my code, and help me find out where the mistakes can be, or provide me
>
> with
>
>>>some reference C code.
>>>
>>>Thanks you very much in advance,
>>
>>Did you see Grant's multirate code on dspguru.com?
>>
>
>
> Hi Jim,
>
> Yes I did. It is not polyphase, right? I'd love it was... Any example in C
> with ployphase implementation?

The interpolation code on dspguru is most definitely polyphase.

My understanding is that polyphase only comes into play during interpolation.
It's only during interpolation that you get the opportunity to skip through the
coefs - essentially choosing a phase of the impulse response. In decimation you
work on contiguous samples, but only calculate the outputs you're going to keep.

Am I wrong?

--
Jim Thomas Principal Applications Engineer Bittware, Inc
[email protected] http://www.bittware.com (603) 226-0404 x536
Hope springs occasionally.