MATLAB: FVTool: filter array as parameter

audioAudio Toolboxdigital signal processingDSP System ToolboxfilterMATLABplot

I would like to pass a filter vector as a parameter to FVTool to automate different plots of my MATLAB script.

Example: I have this:

plotter = fvtool(getFilter(octaveFilterBank{1}), ...
    getFilter(octaveFilterBank{2}), ...
    'FrequencyScale', 'log', ...
    'Fs', Fs);

I want something like this:

% Init the array:
filter_array = [getFilter(octaveFilterBank{1}), ...
      getFilter(octaveFilterBank{2})];
% Plot:
plotter = fvtool(filter_array, ...
    'FrequencyScale', 'log', ...
    'Fs', Fs);

How can I do this?

Best Answer

Hi Nycholas,

Please give the following a try and let us know if it works for you:

filter1 = octaveFilter('CenterFrequency',1000);
filter2 = octaveFilter('CenterFrequency',2000);
filterArray = {getFilter(filter1), getFilter(filter2)};
fvtool(filterArray{:})

Thanks,

Gabriele.

Related Solutions

MATLAB: How use filter from filter designer

y = filter(Hd,x);

x is the signal that you want to filter.

MATLAB: How to use Audio Plugin Example System Objects in a custom Plugin

Hi Adrian,

Take a look at the plugin below and see if this answers your needs. What this plugin does is essentially internally use a var-slope BP filter and a param EQ.

classdef ExampleEQ < audioPlugin
    %#codegen
    properties
        % Cutoff frequency in Hz
        LowCutoff = 20
        HighCutoff = 18e3;
        % Slope in dB/octave
        LowSlope = '12'
        HighSlope = '30'
        CenterFrequency1 = 100
        CenterFrequency2 = 1000
        CenterFrequency3 = 10000
        % Q factors for each band
        QualityFactor1 = 2
        QualityFactor2 = 2
        QualityFactor3 = 2
        % dB gain for each band
        PeakGain1 = 0
        PeakGain2 = 0
        PeakGain3 = 0
    end
    properties (Access = private)
        pVarSlopeBP
        pParamEQ
    end
    properties (Constant)
        % Define the plugin interface
        PluginInterface = audioPluginInterface( ...
            'InputChannels',2,...
            'OutputChannels',2,...
            'PluginName','Example EQ',...
            audioPluginParameter('LowCutoff', ...
            'DisplayName',  'Low Cutoff', ...
            'Label',  'Hz', ...
            'Mapping', { 'log', 20, 20000},...
            'Style', 'rotaryknob', 'Layout', [1 1]),...
            audioPluginParameter('HighCutoff', ...
            'DisplayName',  'High Cutoff', ...
            'Label',  'Hz', ...
            'Mapping', { 'log', 20, 20000},...
            'Style', 'rotaryknob', 'Layout', [1 2]),...
            audioPluginParameter('LowSlope', ...
            'DisplayName',  'Low Slope', ...
            'Label',  'dB/octave', ...
            'Mapping', { 'enum', '0','6','12','18','24','30','36','42','48'},...
            'Layout', [3 1]),...
            audioPluginParameter('HighSlope', ...
            'DisplayName',  'High Slope', ...
            'Label',  'dB/octave', ...
            'Mapping', { 'enum', '0','6','12','18','24','30','36','42','48'},...
            'Layout', [3 2]), ...
            audioPluginParameter('PeakGain1','DisplayName','Low Gain','Label','dB',...
            'Mapping',{'lin',-20,20},'Style','vslider','Layout',[5 1]),...
            audioPluginParameter('CenterFrequency1','DisplayName','Low Frequency','Label','Hz',...
            'Mapping',{'log',20,20e3},'Style','rotaryknob','Layout',[7 1]),...
            audioPluginParameter('QualityFactor1','DisplayName','Low Q',...
            'Mapping',{'log',0.2,700},'Style','rotaryknob','Layout',[9 1]),...
            audioPluginParameter('PeakGain2','DisplayName','Mid Gain','Label','dB',...
            'Mapping',{'lin',-20,20},'Style','vslider','Layout',[5 2]),...
            audioPluginParameter('CenterFrequency2','DisplayName','Mid Frequency','Label','Hz',...
            'Mapping',{'log',20,20e3},'Style','rotaryknob','Layout',[7 2]),...
            audioPluginParameter('QualityFactor2','DisplayName','Mid Q',...
            'Mapping',{'log',0.2,700},'Style','rotaryknob','Layout',[9 2]),...
            audioPluginParameter('PeakGain3','DisplayName','High Gain','Label','dB',...
            'Mapping',{'lin',-20,20},'Style','vslider','Layout',[5 3]),...
            audioPluginParameter('CenterFrequency3','DisplayName','High Frequency','Label','Hz',...
            'Mapping',{'log',20,20e3},'Style','rotaryknob','Layout',[7 3]),...
            audioPluginParameter('QualityFactor3','DisplayName','High Q',...
            'Mapping',{'log',0.2,700},'Style','rotaryknob','Layout',[9 3])...
            );
    end
    %----------------------------------------------------------------------

    % Public methods
    %----------------------------------------------------------------------
    methods
        function plugin = ExampleEQ()
            % Constructor
            % Initialize a multinotch filter
            plugin.pVarSlopeBP = audiopluginexample.VarSlopeBandpassFilter;
            plugin.pParamEQ = audiopluginexample.ParametricEqualizerWithUDP;
            fs = plugin.getSampleRate;
            setSampleRate(plugin.pVarSlopeBP, fs);
            setSampleRate(plugin.pParamEQ, fs);
        end
        %------------------------------------------------------------------


        function set.LowCutoff(plugin,val)
            plugin.pVarSlopeBP.LowCutoff = val;%#ok<MCSUP>












            plugin.LowCutoff = val;
        end
        function set.HighCutoff(plugin,val)
            plugin.pVarSlopeBP.HighCutoff = val;%#ok<MCSUP>
            plugin.HighCutoff = val;
        end
        function set.LowSlope(plugin,val)
            plugin.pVarSlopeBP.LowSlope = val;%#ok<MCSUP>
            plugin.LowSlope = val;
        end
        function set.HighSlope(plugin,val)
            plugin.pVarSlopeBP.HighSlope = val;%#ok<MCSUP>
            plugin.HighSlope = val;
        end
        function set.CenterFrequency1(plugin,val)
            plugin.pParamEQ.CenterFrequency1 = val;%#ok<MCSUP>
            plugin.CenterFrequency1 = val;
        end
        function set.CenterFrequency2(plugin,val)
            plugin.pParamEQ.CenterFrequency2 = val;%#ok<MCSUP>
            plugin.CenterFrequency2 = val;
        end
        function set.CenterFrequency3(plugin,val)
            plugin.pParamEQ.CenterFrequency3 = val;%#ok<MCSUP>
            plugin.CenterFrequency3 = val;
        end
        function set.QualityFactor1(plugin,val)
            plugin.pParamEQ.QualityFactor1 = val;%#ok<MCSUP>
            plugin.QualityFactor1 = val;
        end
        function set.QualityFactor2(plugin,val)
            plugin.pParamEQ.QualityFactor2 = val;%#ok<MCSUP>
            plugin.QualityFactor2 = val;
        end
        function set.QualityFactor3(plugin,val)
            plugin.pParamEQ.QualityFactor3 = val;%#ok<MCSUP>
            plugin.QualityFactor3 = val;
        end
        function set.PeakGain1(plugin,val)
            plugin.pParamEQ.PeakGain1 = val;%#ok<MCSUP>
            plugin.PeakGain1 = val;
        end
        function set.PeakGain2(plugin,val)
            plugin.pParamEQ.PeakGain2 = val;%#ok<MCSUP>
            plugin.PeakGain2 = val;
        end
        function set.PeakGain3(plugin,val)
            plugin.pParamEQ.PeakGain3 = val;%#ok<MCSUP>
            plugin.PeakGain3 = val;
        end
        %------------------------------------------------------------------
        function y = process(plugin,x)
            z = plugin.pVarSlopeBP(x);
            y = plugin.pParamEQ(z);
        end
        %------------------------------------------------------------------
        function reset(plugin)
            fs = plugin.getSampleRate;
            setSampleRate(plugin.pVarSlopeBP, fs);
            reset(plugin.pVarSlopeBP)
            setSampleRate(plugin.pParamEQ, fs);
            reset(plugin.pParamEQ)
        end
    end
end

Best Answer

Related Solutions

MATLAB: How use filter from filter designer

MATLAB: How to use Audio Plugin Example System Objects in a custom Plugin

Related Question