2021-06-03 07:36 AM
I am reviewing another person's program and need to know how the filters are operating for troubleshooting. Here are a few examples from the program I am looking at.
filter_arm_status = arm_fir_decimate_init_q15(&Sine_Filter, 31, 2, FIR_Coeff_Buffer, Sine_State_Buffer, input_buffer_size);
arm_fir_decimate_fast_q15(&Sine_Filter, Sine_Input_Ping_Buffer, Sine_Output_Ping_Buffer, input_buffer_size);
arm_fir_decimate_fast_q15(&Sine_Filter, Sine_Input_Pong_Buffer, Sine_Output_Pong_Buffer, input_buffer_size);
The information that I need is what kind of filter (lowpass, highpass, bandpass) as well as the window type (hamming, hanning, blackman-harris, flat-top)
Everything I have found thus far only documents the variables within each line of code included above. I am having issues determining the type of filter and window for the filter.
2021-06-03 08:10 AM
The FIR coefficients would be in the FIR_Coeff_Buffer array and would dictate the parameters of the filter.
An FIR filter also doesn't really fit within the archetype one typically uses to describe a filter (order, low/high pass, cutoff).
http://t-filter.engineerjs.com/