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Altera_Forum's avatar
Altera_Forum
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17 years ago

3-band equalizer in NIOS

Hello,

I was wandering if anybody can give me a hint about by litle project......I have to implement a 3-band (low-band-high-pass) equalizer in NIOS using UPIP audio core. I have a little problem with programming Nios in C...... I also have implemented this EQ in TI's C6713, using Matlab for the filters design, but in NIOS........ I really could use some help........

If anybody can be of assistance, I would really appreciate it.

thank you a lot

fasmatikos

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Hi,

    Digital filters are normally rahter straightforward programming.

    I once did some performance test on symmetric FIR filters in software, some results in attachment (NIOSII with instruction cache, no data cache).

    Before starting, I think you have to consider if you have performance enough with the pocessor, or if you need to accelerate the algorithm in logic next to the processor.

    How big is the filter order estimated?

    Stefaan
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    The main perpouse of my thesis is the vga core, but i have to iplement a 3-band eq as well. So the filters isnt tha important as the speed is concerned.It will be a 2nd order biquads. I am having trouble implementing this filter in C.... i have no real experience in signal processing...

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    I also think that IIR filter topology is most suitable for an audio filter. Basically you have to find the z-domain transfer functions respectively the differential equations for the filters. Than you should be able to code a HDL or C realisation rather easily. Some filter tools, e. g. Nuhertz filter solutions can create C-code directly, but I don't know if the feature is enabled in the evaluation version.