How to read a *.fcf file and add the filter to workspace?

Hi everyone!

I'm blocked for already a couple of days on a problem regarding the lecture of a .fcf filter file.

Designing a parametric EQ for shaping a simulated frequency response from audio sound, I need to store a multi-stage filter in a folder for later purposes. This part is complete and working properly. I use the fcfwrite function.

% --- Executes on button press in SaveFilter.
function SaveFilter_Callback(hObject,eventdata,handles)
Hd=getappdata(hObject,'Hd');
prompt = {'How do you want to call the designed multi-stage filter?'};
dlg_title = 'Save the parametric Filter';
num_lines=1;
def = {'sf'};
newname = inputdlg(prompt,dlg_title,num_lines,def);
if isempty(newname)==0
    newname=cell2mat(newname);
    assignin('base',newname,Hd);
end
% Export filter in the folder paraEQFilter
fcfwrite(Hd,newname);
fileID=(strcat(newname, '.fcf'));
movefile (fileID, 'paraEQFilter');

However, I'm unable to read the file back as I didn't found an opposite function of fcfwrite. Apparently, there isn't a fcfread function.

My questions are:

How can I read the *.fcf file in order to get the filter in the workspace?

If not possible, how can I store a multi-stage direct-form I filter and get it back?

Answer 1

[Ari Mahpour]

Use the load function but make sure to comment out any non-coefficient lines:

>> load('myfile.fcf')

If you try to load the .fcf file using the load() function with an auto-generated .fcf file you'll likely get an error like this:

Error using load
Unknown text on line number 14 of ASCII file low-pass-5khz.fcf
"Numerator:".

You'll need to either remove that line that says "Numerator:" or comment it out (with a "%").