[CELT-dev] Bitrev for FFT

Riccardo Micci
Thu, 03 Mar 2011 11:42:24 -0000

Hi,
Our DSP has a built-in bitrev instruction so we're exploring the
possibility of calculating the bitrev every time instead of filling the
table during initialisation, hence saving some memory.

Our frame size is fixed to 320 samples. The two FFTs sizes for normal
block and short block are 160 and 40 respectively. It's not really clear
how the function "compute_bitrev_table" calculates the values.
Could you quickly explain the idea behind the function so we can try to
implement it on the fly?

Regards
Riccardo


Riccardo Micci
Senior DSP Engineer, Wireless Group
Cambridge Consultants
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Cambridge, CB4 0DW, England
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riccardo.micci at cambridgeconsultants.com
www.CambridgeConsultants.com






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