STM32F405 MEDIANFILTER

[michael239955_stm1]

Posted on April 04, 2014 at 13:03

Hey,

Does anybody know a DSP-Function for a medianfilter? with filterlength of 5 points. At the moment I have written the filter with for-loops, and it is too slow for my application. Thank you, Michael #m

[frankmeyer9]

Posted on April 04, 2014 at 13:39

The DSP lib for F4 parts (from ST's website) contains a bunch of DSP-like functions, presumably also a filter implementation you can use.

At the moment I have written the filter with for-loops, and it is too slow for my application. How about cranking up optimization level ? As an example, a FFT implementation I tried on a F407 took 10ms with -O0, and 2,4ms with -O3.

[jpeacock2399]

Posted on April 04, 2014 at 16:05

Do you make use of the DSP instruction set for the M4 core?  Depending on your resolution you can do SIMD for 8 and 16 bit values, and there are MAC type instructions.  If you are doing floating point and can use single precision there's the FPU instruction set too.

  Jack Peacock