Intel® Integrated Performance Primitives
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Polyphase "roll-off frequency"

pq7
Beginner
561 Views

For ResamplePolyphaseFixedInit, what exactly is the rollf parameter? It's described as the "roll-off frequency of the filter."

In the examples it's always 0.95, e.g.

ippsResamplePolyphaseFixedInit_16s(inRate,outRate,2*(history-1), 0.95f, 9.0f, state, ippAlgHintFast);

And we get another hint here:

ippStsBadArgErr
Indicates an error when rollf is less than or equal to 0 or is greater than 1

So it seems to be normalized. Is it another term for cutoff/corner frequency?

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Ruqiu_C_Intel
Employee
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Thank you for reaching us. This issue is closing and we will no longer respond to this thread. If you require additional assistance from Intel, please start a new thread. Any further interaction in this thread will be considered community only. 


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3 Replies
NoorjahanSk_Intel
Moderator
536 Views

Hi,

Thanks for reaching out to us.

We are looking into it. We will get back to you soon.


Thanks & Regards

Noorjahan



Andrey_B_Intel
Employee
421 Views

Hi pq7.

The "roll-off frequency"  is "freq" argument of sinc-filter and here it is 'cutoff' frequency relative to sampling frequency but 1.0 means half of sampling frequency so range is (0.0, 1.0)

Andrey

Ruqiu_C_Intel
Employee
370 Views

Thank you for reaching us. This issue is closing and we will no longer respond to this thread. If you require additional assistance from Intel, please start a new thread. Any further interaction in this thread will be considered community only. 


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