firexpofn.m

非常好的数字处理教程

function firexpofn(action,datastruct)
    if nargin < 1
        action='init';
    end

	% Fix freq labels
	% Apply filter shouldn't know about Undo

	name = mfilename;
    figname = [name(1:end-2) '_fig'];
    f=findobj('Tag',figname);
    handles = get(f,'UserData');

    switch action
		case 'help'
			display_help(figname);
        case 'init'
			setdefaults;
			reset(handles.specplot);
            reset(handles.timeplot);
			handles.exponum = 0;
		case 'loadsound'
			handles.audiodata = load_audiodata;
			handles.original = handles.audiodata;
            if ~isfield(handles.audiodata, 'filenamepath')
                return;
            end
            if (size(handles.audiodata.data,2) > 1)
                handles.audiodata.data = to_mono(handles.audiodata.data);
            end
			set(handles.freqzoom,'Value',1.0);
            contents = get(handles.fftsize,'String');
            fftsize = str2double(contents{get(handles.fftsize,'Value')});
            contents = get(handles.Window,'String');
            shape = contents{get(handles.Window,'Value')};
            [handles.spectrum, handles.bin, handles.st] = ...
                spectrogram(handles.audiodata, fftsize, shape);
			handles = makeTimePlot(handles);
			handles = makeSpecPlot(handles);
			linkedzoom([handles.timeplot, handles.specplot],'onx');
            place_header(f,handles);
		case 'readinput'
			handles.audiodata = datastruct;
            clear datastruct;
            if (size(handles.audiodata.data,2) > 1)
                handles.audiodata.data = to_mono(handles.audiodata.data);
            end
			set(handles.freqzoom,'Value',1.0);
			handles.original = handles.audiodata;
            contents = get(handles.fftsize,'String');
            fftsize = str2double(contents{get(handles.fftsize,'Value')});
            contents = get(handles.Window,'String');
            shape = contents{get(handles.Window,'Value')};
            [handles.spectrum, handles.bin, handles.st] = ...
                spectrogram(handles.audiodata, fftsize, shape);
            handles = makeTimePlot(handles);
            handles = makeSpecPlot(handles);
            linkedzoom([handles.timeplot, handles.specplot],'onx');
            place_header(f,handles);
		case {'playsound', 'playoriginal'}
            if isfield(handles,'audiodata')
			    times = get(handles.specplot,'XLim');
                switch action
                    case 'playsound'
                        audiodata = handles.audiodata;
                        button = handles.play;
                    case 'playoriginal'
                        audiodata = handles.original;
                        button = handles.playoriginal;
                end
                samples = floor(times*audiodata.Fs);
                if (samples(1) <= 0)
                   samples(1) = 1;
                end
                if (samples(2) > length(audiodata.data))
                   samples(2) = length(audiodata.data);
                end
                audiodata.data = audiodata.data(samples(1):samples(2));
                if (max(abs(audiodata.data)) > 1.0)
                    audiodata.data = normalize(audiodata.data);
                end
                play_audiodata(audiodata, button);
            end
		case {'db','inverse','interpolate','colormap','fftdisplay'}
			if isfield(handles,'audiodata')
				updateSpecPlot(handles);
                set(handles.specplot,'XLim',get(handles.timeplot,'XLim'));
                firexpofn 'freqzoom';
			end
		case {'fftsize','window'}
			if isfield(handles,'audiodata')
				contents = get(handles.fftsize,'String');
                fftsize = str2double(contents{get(handles.fftsize,'Value')});
                contents = get(handles.Window,'String');
                shape = contents{get(handles.Window,'Value')};

                [handles.spectrum, handles.bin, handles.st] = ...
                    spectrogram(handles.audiodata, fftsize, shape);
                updateSpecPlot(handles);
                set(handles.specplot,'XLim',get(handles.timeplot,'XLim'));
                firexpofn 'freqzoom';
			end
		case 'normalize'
			if isfield(handles,'audiodata')
				handles.audiodata.data = normalize(handles.audiodata.data);
				xlim = get(handles.timeplot,'XLim');
				handles = makeTimePlot(handles);
                contents = get(handles.fftsize,'String');
                fftsize = str2double(contents{get(handles.fftsize,'Value')});
                contents = get(handles.Window,'String');
                shape = contents{get(handles.Window,'Value')};

                [handles.spectrum, handles.bin, handles.st] = ...
                    spectrogram(handles.audiodata, fftsize, shape);
                updateSpecPlot(handles);
                set(handles.timeplot,'XLim',xlim);
                set(handles.specplot,'XLim',xlim);
                firexpofn 'freqzoom';
            end
		case 'explore_data'
			explore_data(handles);
		case 'plotfreqz'
			plotfreqz(handles);
		case 'apply_filter'
			if isfield(handles, 'audiodata')
				handles = apply_filter(handles);
				contents = get(handles.fftsize,'String');
                fftsize = str2double(contents{get(handles.fftsize,'Value')});
                contents = get(handles.Window,'String');
                shape = contents{get(handles.Window,'Value')};

                [handles.spectrum, handles.bin, handles.st] = ...
                    spectrogram(handles.audiodata, fftsize, shape);
                updateSpecPlot(handles);
                Xlim = get(handles.timeplot,'XLim');
				handles = makeTimePlot(handles);
                set(handles.specplot,'XLim',Xlim);
                set(handles.timeplot,'XLim',Xlim);
                firexpofn 'freqzoom';
			end
        case 'freqzoom'
            if isfield(handles,'audiodata')
                val = get(handles.freqzoom,'Value');
                if val == 0,
                    val = 0.001;
                end
                Fs = handles.audiodata.Fs;
                set(handles.specplot,'YLim',[0 val*Fs/2])
            end
        case 'zoomreset'
            if isfield(handles,'audiodata')
                handles = makeTimePlot(handles);
                set(handles.specplot,'XLim',get(handles.timeplot,'XLim'));
                linkedzoom([handles.timeplot, handles.specplot],'onx');
            end
		case 'save'
			if isfield(handles, 'audiodata')
				save_audiodata(handles.audiodata);
			end
		case 'undo'
            if isfield(handles,'audiodata')
			    handles = undo(handles);
			    updateSpecPlot(handles);
                Xlim = get(handles.timeplot,'XLim');
			    handles = makeTimePlot(handles);
                set(handles.specplot,'XLim',Xlim);
                set(handles.timeplot,'XLim',Xlim);
                firexpofn 'freqzoom';
            end
		case {'pzexpo','pzfilterexpo'}
			[a_k,b_k] = designfilter(handles);
			[data.zeropos,data.polepos] = tf2zpk(b_k,a_k);
			switch action
				case 'pzexpo'
					pzexpogui(data);
				case 'pzfilterexpo'
					pzfilterexpogui(data);
			end
		case 'convexpo'
			[a_k,b_k] = designfilter(handles);
			data.impulse = b_k;
			convexpogui(data);
		case {'fourier'}
			if isfield(handles,'audiodata')
				audiodata = handles.audiodata;
				fourierexpogui(audiodata);
			end
		case 'print'
			print_figure(f);
		case 'close'
			close_figure(f,figname(1:end-4));
            return;
	end
	set(f,'UserData',handles);

% --------------------------------------------------------------------
function handles = makeTimePlot(handles);
	handles.t = [0:1/handles.audiodata.Fs:(length(handles.audiodata.data)-1)/...
        handles.audiodata.Fs];
	axes(handles.timeplot)
	plot(handles.t,handles.audiodata.data)
	maxtime = length(handles.t)/handles.audiodata.Fs;
	set(handles.timeplot,'XLim',[0 maxtime]);
	set(handles.timeplot,'YLim',[-1.0 1.0]);
	grid;
	xlabel('time (s)');

function handles = makeSpecPlot(handles);
	axes(handles.specplot);
	handles.pos = get(gca,'Position'); % Save axes position
	if (get(handles.interpolate,'Value'))
		if (get(handles.dBcheckbox,'Value'))
			pcolor(handles.st,handles.bin,20*log10(abs(handles.spectrum)));
		else
			pcolor(handles.st,handles.bin,abs(handles.spectrum));
		end
		shading interp;
	else
		if (get(handles.dBcheckbox,'Value'))
			imagesc(handles.t,handles.bin,20*log10(abs(handles.spectrum)));
		else
			imagesc(handles.t,handles.bin,abs(handles.spectrum));
		end
	end

	axis xy;
	ylabel('Frequency (Hz)');
	colormap('Jet');
	set(handles.specplot,'XTickLabel',['']);
	h = colorbar('vert');
	if (get(handles.dBcheckbox,'Value'))
		set(get(h, 'YLabel'), 'String', 'dB');
	else
		set(get(h, 'YLabel'), 'String', 'Amplitude');