view aim-mat/gui/adaptedspecgramdemo.m @ 4:537f939baef0 tip

various bug fixes and changed copyright message

function out=adaptedspecgramdemo(y,Fs,t_min,t_max)
%SPECGRAMDEMO Spectrogram Demo
%   SPECGRAMDEMO(y,Fs) displays a spectrogram of signal y, assuming
%   a sample rate of Fs Hz.  If y is specified but Fs is not,
%   a sample rate of 1 Hz is assumed.  If no input arguments
%   are supplied, y and Fs are taken from the default data file
%   "mtlb.mat."
%
%   Context menus and context-sensitive help are enabled throughout
%   the GUI.  Explore the visualization options by right-clicking
%   on various GUI items including the spectrogram, the colorbar,
%   etc.  For example, the panner may be zoomed by dragging the
%   mouse on the left- and right-hand edges of the highlighted
%   zoom region.  Right-clicking the highlighted zoom area brings
%   up a menu for focusing in on the zoom region, and provides
%   a link to context help.
%
% See also SPECGRAM, SPTOOL, FDATOOL.

% Author: D. Orofino
% Copyright 1988-2002 The MathWorks, Inc.
% $orginal Revision: 1.11 $ $orginal Date: 2002/05/17 14:17:56 $
% 
%
% adapted by Stefan Bleeck 5.3.2003 to give back the selected time.
% [e-mail]

%%%%%%%%%%%%%%%%%%%%%%%%%%
% inserted by S.Bleeck
global tmin;
global tmax;
if nargin<4
	t_max=length(y)/Fs;
end
if nargin<3
	t_min=0;
end
tmin=0;
tmax=length(y);
%%%%%%%%%%%%%%%%%%%%%%%%%%

if nargin<1,
   default_file = 'mtlb.mat';
   fprintf(['Loading demo file (%s).\n\n'],default_file);
   s = load(default_file);
   y  = s.mtlb; % default dataset
   Fs = s.Fs;
elseif nargin<2,
    Fs=1;  % default sample rate
end

create_gui(y,Fs,t_min,t_max);


%%%%%%%%%%%%%%%%%%%%%%%%%%
% inserted by S.Bleeck
out.start=tmin/Fs;
out.duration=tmax/Fs-tmin/Fs;
%%%%%%%%%%%%%%%%%%%%%%%%%%



%---------------------------------------------------------------
function zoom_in(hco,eventStruct,hfig)

if nargin<3, hfig=gcbf; end

ud = get(hfig,'userdata');

% Get "pixel spacing" of image content
im_xdata = get(ud.himage,'xdata');
im_dx    = im_xdata(2)-im_xdata(1);

% Get current axis limit
xlim     = get(ud.hax(1),'xlim');
xlim_ctr = sum(xlim)/2;
dxlim    = diff(xlim);

% If current axis limits will only show 1 pixel width,
% don't bother zooming in any further:
if dxlim <= im_dx, return; end

% Shrink limits 50% toward center of current limits:
new_xlim = (xlim + xlim_ctr)/2;
% Update the spectrogram and time slice axes:
set(ud.hax(1),'xlim',new_xlim);  % [1 3] xxxx

% Update the thumbnail:
set(ud.hthumb,'xdata',new_xlim([1 2 2 1 1]));

% update the audio selection to be played
set_audio_selection(hfig, new_xlim * ud.Fs);

% Update zoom signal, if enabled:
% xxx plot_signal_zoom(hfig);

%---------------------------------------------------------------
function zoom_out(hco,eventStruct,hfig)

% Zooming is relative to the current focus window
% We will not zoom out beyond the current focus window

if nargin<3, hfig=gcbf; end
ud = get(hfig,'userdata');

% Get current spectrogram axis limit (= thumbnail limits)
thumb_xlim = get(ud.hax(1),'xlim'); % thumb limits = spectrogram limits
thumb_dx = diff(thumb_xlim);

% If spectrogram axis limits >= focus window limits,
% don't bother zooming out any further:
hax_time = ud.hax(2);
focus_xlim = get(hax_time,'xlim');  % = panner xlim
focus_dx = focus_xlim(2)-focus_xlim(1);
if thumb_dx >= focus_dx, return; end

% Grow limits 50% away from center of current limits:
new_xlim = thumb_xlim + [-thumb_dx thumb_dx]/2;
if new_xlim(1)<focus_xlim(1), new_xlim(1)=focus_xlim(1); end
if new_xlim(2)>focus_xlim(2), new_xlim(2)=focus_xlim(2); end

% Update the thumbnail:
set(ud.hthumb,'xdata',new_xlim([1 2 2 1 1]));

% Sync the spectrogram and time slice axes to the thumbnail:
set(ud.hax(1),'xlim',new_xlim); % [1 3] xxxx

% update the audio selection to be played
set_audio_selection(hfig, new_xlim * ud.Fs);

% Update zoom signal, if enabled:
% xxx plot_signal_zoom(hfig);

%---------------------------------------------------------------
function zoom_full(hco,eventStruct,hfig)

if nargin<3, hfig=gcbf; end
ud = get(hfig,'userdata');

focusTimeReset(hfig);  % reset focus window to full extent

% Get time range of full spectrogram
im_xdata = get(ud.himage,'xdata');

% Grow limits 50% away from center of current limits:
new_xlim(1)=im_xdata(1);
new_xlim(2)=im_xdata(end);

% Update the spectrogram and time slice axes:
set(ud.hax([1 3]),'xlim',new_xlim);

% Update the thumbnail:
set(ud.hthumb,'xdata',new_xlim([1 2 2 1 1]));

% update the audio selection to be played
set_audio_selection(hfig, new_xlim * ud.Fs);

% Update zoom signal, if enabled:
% xxx plot_signal_zoom(hfig);

%---------------------------------------------------------------
function top_plot_toggle

% XXX UNUSED?

hfig=gcbf;
ud=get(hfig,'userdata');

if strcmp(ud.plot.top,'spectrogram_time_slice'),
   newMode='signal_zoom';
else
   newMode='spectrogram_time_slice';
end
ud.plot.top=newMode;
set(hfig,'userdata',ud);

hax_tslice = ud.hax(3);

if strcmp(newMode,'signal_zoom'),
   t = (0:length(ud.y)-1)/ud.Fs;
   set(ud.htslice_line,'xdata',t, 'ydata', ud.y);
   set(hax_tslice,'xlim',[0 max(t)],'ylimmode','auto');
else
   % xxx
   set(ud.htslice_line,'ydata', get_spec_tslice(hfig), ...
      'xdata',ud.t);
   
   b = get(ud.himage,'cdata');
   blim = [min(b(:)) max(b(:))];
   spec_xlim = [0 max(ud.t)];
   set(hax_tslice, 'xlim',spec_xlim, 'ylim',blim);
end

% Update the top plot (Time slice)
%update_top_plot(hfig);

%---------------------------------------------------------------
function left_plot_toggle
% Define the newMode flag in ud.plot.left

hfig = gcbf;
ud = get(hfig,'userdata');

if strcmp(ud.plot.left,'spectrogram_freq_slice'),
	newMode = 'signal_psd';
else
   newMode = 'spectrogram_freq_slice';
end
ud.plot.left = newMode;
set(hfig,'userdata',ud);

% Update the left plot (Frequency slice and PSD)
update_left_plot(hfig);

%---------------------------------------------------------------
function set_crosshairs(hfig,x,y)

% Get current point in axis ASAP:
%hfig   = gcbf;
ud = get(hfig,'userdata');

% Update cache
ud.crosshair.xctr = x;
if nargin == 3,
    ud.crosshair.yctr = y;
else
    y = ud.crosshair.yctr;
end
set(hfig,'userdata',ud);

% Update crosshairs
set([ud.hspec_y ud.htime_y ud.htslice_y], 'xdata',[x x]);
set([ud.hspec_x ud.hfreq_x], 'ydata',[y y]);

% Update readouts
update_time_readout(hfig);
update_freq_readout(hfig);
update_dB_readout(hfig);
update_cmap_ptr(hfig);

% For the VERTICAL and H/V crosshairs,
% update the freq slice display:
if strcmp(ud.plot.left,'spectrogram_freq_slice'),
   set(ud.hfreq_line,'xdata', get_spec_freq(hfig));
end

% For the HORIZONTAL and H/V crosshairs,
% update the time slice display:
if strcmp(ud.plot.top,'spectrogram_time_slice'),
   set(ud.htslice_line,'ydata', get_spec_tslice(hfig));
end

%---------------------------------------------------------------
function center_cross(hco,eventStruct)

hfig = gcbf;
ud = get(hfig,'userdata');

% Determine center of spectrogram axis:
xlim=get(ud.hax(1),'xlim');
ylim=get(ud.hax(1),'ylim');

set_crosshairs(hfig,mean(xlim),mean(ylim));
update_cmap_ptr(hfig);

%---------------------------------------------------------------
function wbmotion_thumb(hco,eventStruct)
% thumbnail motion

% Get current point in axis ASAP:
hfig   = gcbf;
ud     = get(hfig,'userdata');
hax    = ud.hax(2);
cp     = get(hax,'currentpoint');
curr_x = cp(1,1);

xdata   = get(ud.hthumb,'xdata');
xmotion = curr_x - ud.thumb.origPt;
width   = ud.thumb.width;
xdata   = ud.thumb.xdata + xmotion;

% Constrain to axis limits, so we don't lose cursor:
xlim=get(hax,'xlim');
min_xdata = min(xdata);
max_xdata = max(xdata);
if min_xdata < xlim(1),
   xdata=[xlim(1) xlim([1 1])+width xlim([1 1])];
elseif max_xdata > xlim(2),
   xdata = [xlim(2)-width xlim([2 2]) xlim([2 2])-width];
end

% If the patch is larger than the zoom window
if min(xdata)<=xlim(1) & max(xdata)>=xlim(2),
   % error('wbmotion_thumb: xdata is out of bounds');
	return
end

% Update the thumbnail:
set(ud.hthumb,'xdata',xdata);

% Scroll the spectrogram and time-slice axes:
% xxxx
set(ud.hax([1]),'xlim',xdata(1:2));  % [1 3] xxx

% update the audio selection to be played
set_audio_selection(hfig, xdata(1:2) * ud.Fs);

%if strcmp(ud.plot.top,'spectrogram_time_slice'),
%   set(ud.htslice_line,'ydata', get_spec_tslice(hfig)); % xxxx
%end

%---------------------------------------------------------------
function wbmotion_thumbleft(hco,eventStruct)
% thumbnail LEFT motion

% Get current point in axis ASAP:
hfig   = gcbf;
ud     = get(hfig,'userdata');

% current object may be either the patch, or the signal line
hax    = ud.hax(2);
cp     = get(hax,'currentpoint');
curr_x = cp(1,1);

xdata   = get(ud.hthumb,'xdata');
xmotion = curr_x - ud.thumb.origPt;
width   = ud.thumb.width;
xdata   = ud.thumb.xdata;
xdata([1 4 5]) = xdata([1 4 5]) + xmotion;

% Constrain to axis limits, so we don't lose cursor:
xlim = get(hax,'xlim');
min_xdata = min(xdata);
if min_xdata < xlim(1),
   xdata=[xlim(1) xdata([2 3])' xlim([1 1])];
elseif min_xdata >= xdata(2),
   xdata = ud.thumb.xdata;
end

% Update the thumbnail:
set(ud.hthumb,'xdata',xdata);

% Scroll the spectrogram:
set(ud.hax(1),'xlim',xdata(1:2));

% update the audio selection to be played
set_audio_selection(hfig, xdata(1:2) * ud.Fs);

%---------------------------------------------------------------
function wbmotion_thumbright(hco,eventStruct)
% thumbnail RIGHT motion

% Get current point in axis ASAP:
hfig   = gcbf;
ud     = get(hfig,'userdata');

hax    = ud.hax(2);
cp     = get(hax,'currentpoint');
curr_x = cp(1,1);

xdata   = get(ud.hthumb,'xdata');
xmotion = curr_x - ud.thumb.origPt;
width   = ud.thumb.width;
xdata   = ud.thumb.xdata;
xdata([2 3]) = xdata([2 3]) + xmotion;

% Constrain to axis limits, so we don't lose cursor:
xlim = get(hax,'xlim');
max_xdata = max(xdata);
if max_xdata > xlim(2),
   xdata([2:3]) = xlim(2);
elseif max_xdata <= xdata(1),
   xdata = ud.thumb.xdata;
end

% Update the thumbnail:
set(ud.hthumb,'xdata',xdata);

% Scroll the spectrogram:
set(ud.hax(1),'xlim',xdata(1:2));

% update the audio selection to be played
set_audio_selection(hfig, xdata(1:2) * ud.Fs);

%---------------------------------------------------------------
function wbup_thumb(hco,eventStruct)

% set spectrogram and time-slice xlims
hfig = gcbf;
ud = get(hfig,'userdata');
xdata = get(ud.hthumb,'xdata');
xlim = [min(xdata) max(xdata)];

% Commented out, due to flash:
%set(ud.hax([1 3]),'xlim',xlim);
%
% This is fine:
%set(ud.hax(1),'xlim',xlim);
%
% xxx the following line causes flash in the spect image
% this is the time-slice axis:
% xxx xxx BAD NEWS!
% why does this affect the spectrogram axis? (overlap? clipping?)
%set(ud.hax(3),'xlim',xlim);

changePtr(gcbf,'hand');
install_cursorfcns(gcbf,'thumb');

% Turn back on image axis visibility,
% which was turned off during wbdown_thumb
% so that it does not flash while panning:
% xxx
% Leave off!
%set(ud.hax(1),'vis','on');
%
% Turn on crosshair visibility, which was shut off
% during thumbnail panning (wbdown_thumb):
set([ud.hspec_y ud.hspec_x ud.htslice_y],'vis','on');

%---------------------------------------------------------------
function wbup_thumbleft(hco,eventStruct)
% set spectrogram and time-slice xlims
hfig = gcbf;
ud = get(hfig,'userdata');
xdata = get(ud.hthumb,'xdata');
xlim = [min(xdata) max(xdata)];

% Commented out, due to flash:
%set(ud.hax([1 3]),'xlim',xlim);
%
% This is fine:
set(ud.hax(1),'xlim',xlim);
%
% xxx the following line causes flash in the spect image
% this is the time-slice axis:
% xxx xxx xxx
%set(ud.hax(3),'xlim',xlim);

changePtr(gcbf,'ldrag');
install_cursorfcns(gcbf,'thumbleft');

% Turn on crosshair visibility, which was shut off
% during thumbnail panning (wbdown_thumb):
set([ud.hspec_y ud.hspec_x],'vis','on');

%---------------------------------------------------------------
function wbup_thumbright(hco,eventStruct)
% set spectrogram and time-slice xlims
hfig = gcbf;
ud = get(hfig,'userdata');
xdata = get(ud.hthumb,'xdata');
xlim = [min(xdata) max(xdata)];

% Commented out, due to flash:
%set(ud.hax([1 3]),'xlim',xlim);
%
% This is fine:
set(ud.hax(1),'xlim',xlim);
%
% xxx the following line causes flash in the spect image
% this is the time-slice axis:
% xxx xxx
%set(ud.hax(3),'xlim',xlim);

changePtr(gcbf,'rdrag');
install_cursorfcns(gcbf,'thumbright');

% Turn on crosshair visibility, which was shut off
% during thumbnail panning (wbdown_thumb):
set([ud.hspec_y ud.hspec_x],'vis','on');

%---------------------------------------------------------------
function update_status(hfig,str)
% UPDATE_STATUS Update status text.

% If str is not a string, skip
% -1 is often used to "skip" the update
if ischar(str),
   ud = get(hfig,'userdata');
   set(ud.htext_status,'string',str);
end

%---------------------------------------------------------------
function play_sound(hco, eventStruct)
% PLAY_SOUND Play the selected sound segment

hfig = gcbf;
ud = get(hfig,'userdata');
y = get(ud.htime_plot,'ydata');
Fs = ud.Fs;

xdata=get(ud.hthumb,'xdata');
xlim=[min(xdata) max(xdata)];
xidx=floor(xlim*Fs)+1;
if xidx(1)<1, xidx(1)=1; end
if xidx(2)>length(y), xidx(2)=length(y); end

% Normalize sound and play:
mx=max(abs(y));
try
   wavplay(y(xidx(1):xidx(2))./mx,Fs,'sync');
catch
   msg = lasterr;
   errordlg(msg,'Audio Playback Error','modal');
end

%---------------------------------------------------------------
% called by audioplayer during playback (if audioplayer enabled)
function update_audio_position(hco, eventStruct)
if hco.isplaying,   % only do this if playback is in progress
    currentPosition = get(hco, 'CurrentSample') / get(hco, 'SampleRate');
    set_crosshairs(get(hco, 'UserData'), currentPosition);
end

%---------------------------------------------------------------
% utility to easily set playback boundaries
function set_audio_selection(hfig, selectionPair)
%%%%%%%%%%%%%%%%%%%%%%%%%%
% inserted by S.Bleeck
global tmin;
global tmax;
%%%%%%%%%%%%%%%%%%%%%%%%%%
if ~ isempty(getappdata(hfig, 'audioSelection')), % only do this if audioplayer enabled
    selection.inPoint = selectionPair(1);
    if selection.inPoint < 1, selection.inPoint = 1; end
    selection.outPoint = selectionPair(2);
    setappdata(hfig, 'audioSelection', selection);
	%%%%%%%%%%%%%%%%%%%%%%%%%%
	% inserted by S.Bleeck
	% set the global times, so that we can pick them up
	tmin=selection.inPoint;
	tmax=selection.outPoint;
	%%%%%%%%%%%%%%%%%%%%%%%%%%
end

%---------------------------------------------------------------
% used to set the "put back position" of the vertical crosshair
function start_function(hobj, eventStruct)
hfig = get(hobj, 'UserData');
ud = get(hfig,'userdata');
set(hobj, 'StopFcn', {@stop_function, ud.crosshair.xctr});

%---------------------------------------------------------------
% when playback has completed, puts back the vertical crosshair 
% to where it was when playback was initiated
function stop_function(hobj, eventStruct, where)
while isplaying(hobj), pause(0); end  % let playback complete
if get(hobj, 'CurrentSample') == 1, % if paused, don't put it back
    set_crosshairs(get(hobj, 'UserData'), where);
end

%---------------------------------------------------------------
function set_cmap_limits(hfig, new_dr)
% Set new colormap limits

ud = get(hfig,'userdata');
hax_spec = ud.hax(1);
hax_cbar = ud.hax(5);
himage_cbar = ud.himage_cbar;

% Set new dynamic range limits into spectrogram image
set(hax_spec,'clim',new_dr);

% colorbar is 1:256
% actual spectrogram dynamic range is orig_dr
% new spectrogram dynamic range is new_dr
orig_dr = get(himage_cbar,'ydata');
diff_dr = new_dr - orig_dr;
cmapIndices_per_dB = 256./diff(orig_dr);  % a constant
diff_clim = diff_dr .* cmapIndices_per_dB;
cbar_clim = [1 256] + diff_clim;
set(himage_cbar,'cdatamapping','scaled');  % do during creation
set(hax_cbar,'clim',cbar_clim);

%---------------------------------------------------------------
function reset_cmap_limits(hco,eventStruct)
% Reset colormap limits to dynamic range of spectrogram data

hfig = gcbf;
ud = get(hfig,'userdata');
orig_dr = get(ud.himage_cbar,'ydata');
set_cmap_limits(hfig, orig_dr);

%---------------------------------------------------------------
function manual_cmap_limits(hco,eventStruct,hfig)
% manual_cmap_limits Manual change to colormap dynamic range limits

if nargin<3,
	hfig = gcbf;
end
ud = get(hfig,'userdata');
hax_spec = ud.hax(1);

% Prompt for changes to cmap limits:
clim = get(hax_spec,'clim');
% 'dB value of first color in colormap:'
% 'dB value of last color in colormap:'
prompt={'Value of top color in colormap (dB):', ...
        'Value of bottom color in colormap (dB):'};
def = {num2str(clim(2)), num2str(clim(1))};
dlgTitle='Adjust dynamic range of colormap';
lineNo=1;
strs=inputdlg(prompt,dlgTitle,lineNo,def);
if isempty(strs),
   return
end
new_dr = [str2num(strs{2}) str2num(strs{1})];

set_cmap_limits(hfig,new_dr);

%---------------------------------------------------------------
function wbmotion_cmap(hco,eventStruct)
% WBMOTION_CMAP Graphical change to colormap dynamic range limits

hfig = gcbf;
ud = get(hfig,'userdata');
hax_spec = ud.hax(1);
hax_cbar = ud.hax(5);

% Determine cursor starting and current points ASAP:
cp    = get(hax_cbar,'CurrentPoint');
newPt = cp(1,2);  % y-coord only
dy    = newPt - ud.cbar.origPt;

% if SelectionType was normal,
%   update top or bottom of colorbar, only,
%   depending on whether user started drag
%   in the top or bottom of bar, respectively.
% if SelectionType was extend,
%   update both top AND bottom of bar simultaneously,
%   translating colormap region.
if strcmp(ud.cbar.SelectionType,'extend'),
   change_dr = [dy dy];
else
   if ud.cbar.StartInTop,
      change_dr = [0 dy];
   else
      change_dr = [dy 0];
   end
end
new_dr = ud.cbar.starting_dr + change_dr;
if diff(new_dr)<=0,
   new_dr = ud.cbar.starting_dr;
end

% Colorbar range is 1 to 256.
% Actual spectrogram dynamic range is orig_dr
% New spectrogram dynamic range is new_dr
orig_dr = get(ud.himage_cbar,'ydata');    % a constant
cmapIndices_per_dB = 256./diff(orig_dr);  % a constant
diff_dr = new_dr - orig_dr;
diff_clim = diff_dr .* cmapIndices_per_dB;
cbar_clim = [1 256] + diff_clim;

if diff(cbar_clim)>0,
   % Protect against poor choice of values
   set(hax_cbar,'clim',cbar_clim,'userdata',new_dr);
end

% We defer setting the new dynamic range limits
% into the spectrogram image axis, as it will create
% too much flash. Instead, on button-up, the new
% limit is set.  See wbup_cmap() for details.

% Set new dynamic range limits into spectrogram image
% Note: userdata could be empty if this is the first entry...
% xxx
%set(ud.hax(1),'clim',new_dr);
set(hax_spec,'clim',new_dr);

%---------------------------------------------------------------
function isChange = changePtr(hfig, newPtr)

% Get current pointer name:
ud = get(hfig,'userdata');

% Is this a change in pointer type?
isChange = ~strcmp(ud.currPtr,newPtr);
if isChange,
   setptr(hfig, newPtr);
   ud.currPtr = newPtr;
   set(hfig,'userdata',ud);
end

%---------------------------------------------------------------
function wbmotion_general(hco,eventStruct,hfig)
% General button motion
%
% Determines if cursor is over a crosshair
% If so, changes pointer and installs crosshair buttondowns
% If not, changes back to normal cursor and general buttondowns
%   as necessary.

if nargin<3,
   hfig = gcbf;
end
[isOverHV, isSegmentAxis, isCmapAxis,isTopHalfCmap, isThumb] = ...
   over_crosshair(hfig);

if ~any(isOverHV),
   % Not hovering over a crosshair
   
   if isSegmentAxis,
      % Over an axis in which we can get a delta-time measurement
      if changePtr(hfig,'crosshair'),
         install_cursorfcns(hfig,'segment');
      end
            
   elseif isCmapAxis,
      % Over the colormap axes
      % Install the up/down pointer:
      if isTopHalfCmap,
         if changePtr(hfig,'udrag'),
            update_status(hfig,'Adjust upper dynamic range (shift to translate)');
            install_cursorfcns(hfig,'cmap');
         end
      else
         if changePtr(hfig,'ddrag'),
            update_status(hfig,'Adjust lower dynamic range (shift to translate)');
            install_cursorfcns(hfig,'cmap');
         end
      end
      
   elseif any(isThumb),
      % Over thumbnail - isThumb is a 3-element vector, [left center right],
      %  indicating whether cursor is over left edge, right edge, or is over
      %  the general thumbnail patch itself.
      
      % Install appropriate pointer:
	   if isThumb(1),
          % Over left edge
          if changePtr(hfig,'ldrag'),
              install_cursorfcns(hfig,'thumbleft');
          end
      elseif isThumb(3),
          % Over right edge
          if changePtr(hfig,'rdrag'),
              install_cursorfcns(hfig,'thumbright');
          end
      else
          % Over general patch region
          if changePtr(hfig,'hand'),
              install_cursorfcns(hfig,'thumb');
          end
      end
      
   else
      % Not over a special axes:
      if changePtr(hfig,'arrow'),
         install_cursorfcns(hfig,'general');
      end
   end
   
else
   % Pointer is over a crosshair (vert or horiz or both)
   if all(isOverHV),
      % Over both horiz and vert (near crosshair center):
      if changePtr(hfig,'fleur'),
         install_cursorfcns(hfig,'hvcross');
      end
   elseif isOverHV(1),
      % Over H crosshair
      if changePtr(hfig,'uddrag'),
         install_cursorfcns(hfig,'hcross');
      end
   else
      % Over V crosshair
      if changePtr(hfig,'lrdrag'),
         install_cursorfcns(hfig,'vcross');
      end
   end
end

%---------------------------------------------------------------
function [y,isSegmentAxis,isCmapAxis,...
		isTopHalfCmap, isThumb] = over_crosshair(hfig)
% Is the cursor hovering over the crosshairs?
% There are two crosshairs, one an H-crosshair, the other
% a V-crosshair.  The H and V crosshairs span several
% different axes.
%
% Function returns a 2-element vector, indicating whether
% the cursor is currently over the H- and/or V-crosshairs.
%    y = [isOverH isOverV]

y             = [0 0];
isSegmentAxis = 0;
isCmapAxis    = 0;
isTopHalfCmap = 0;
isThumb       = [0 0 0];  % left, middle, right regions

% First, are we over any axes?
hax = overAxes(hfig);
if isempty(hax), return; end  % not over an axis

% Get current point in axis:
cp = get(hax,'currentpoint');
ud = get(hfig,'userdata');

% Axis which are "segmentable" have a vertical crosshair
% e.g., spectrogram and time axes only
isCmapAxis    = (hax==ud.hax(5));
isSegmentAxis = (hax==ud.hax(1));

% Determine if any horiz or vert crosshairs are
% in this axis ... store as [anyHoriz anyVert]:
hasHVCrossHairs = [any(hax==ud.hax([1 4])) ...
                   any(hax==ud.hax(1:3))];

% Is cursor in colormap axis?
if (isCmapAxis),
   % is cursor in top half of colormap axis?
   orig_dr = get(ud.hax(1),'clim');
   isTopHalfCmap = (cp(1,2) >= sum(orig_dr)/2);
end

if any(hasHVCrossHairs),
   % Get cursor & crosshair positions:
   crosshair_pos = [ud.crosshair.xctr ud.crosshair.yctr];
   cursor_delta  = abs(crosshair_pos - cp(1,1:2));
   axis_dx       = diff(get(hax,'xlim'));
   axis_dy       = diff(get(hax,'ylim'));
   axis_delta    = [axis_dx axis_dy];
   
   % Is cursor within 1 percent of crosshair centers?
   % Limit test uses the reciprocal of the percentage tolerance
   %   1-percent -> 1 / 0.01 = 100
   % 1.5-percent -> 1 / 0.015 ~= 67
   %   2-percent -> 1 / 0.02 = 50
   %
   % Finally, allow a true result only if the axis
   % has a crosshair of the corresponding type
   %
   y = fliplr(cursor_delta * 67 < axis_delta) & hasHVCrossHairs;
end

% Are we over the thumbnail patch?
% Check if we're over the time axis:
if (hax == ud.hax(2)),
   % Get thumb patch limits:
   xdata=get(ud.hthumb,'xdata');
   xlim=[min(xdata) max(xdata)];
   
   % Is cursor over general patch area?
   thumb_delta = xlim - cp(1,1);
   isThumb(2) = thumb_delta(1)<=0 & thumb_delta(2)>=0;
   
   % Is cursor over left or right thumbnail edge?
   % Use same tolerance as crosshair test:
   axis_dx        = diff(get(hax,'xlim'));
   isThumb([1 3]) = (abs(thumb_delta) * 67 < axis_dx);
end

%---------------------------------------------------------------
function h=overAxes(hfig)
% overAxes Determine if pointer is currently over an
% axis of the figure; the axis list comes from the
% figure UserData (ud.hax).

p = get(0,'PointerLocation');
figPos = get(hfig,'Position');
if ~isempty(figPos),
   x  = (p(1)-figPos(1))/figPos(3);
   y  = (p(2)-figPos(2))/figPos(4);
   ud = get(hfig,'userdata');
   for h = ud.hax,
      r = get(h,'Position');
      if (x > r(1)) & (x < r(1)+r(3)) & ...
         (y > r(2)) & (y < r(2)+r(4)),
         return;
      end
   end
end
h = [];
return

%---------------------------------------------------------------
function y=isLeftClick(hfig)

% Keywords for key/button combinations:
%         Left    Right
%   none: normal  alt
%  Shift: extend  alt
%   Ctrl: alt     alt
% Double: open    alt

y=strcmp(get(hfig,'SelectionType'),'normal');

%---------------------------------------------------------------
function wbdown_hcross(hco,eventStruct)
% window button down in h-crosshair mode
if ~isLeftClick(gcbf), return; end
install_cursorfcns(gcbf,'hcross_buttondown');
wbmotion_cross([],[],'h');

%---------------------------------------------------------------
function wbdown_vcross(hco,eventStruct)
% window button down in v-crosshair mode
if ~isLeftClick(gcbf), return; end
install_cursorfcns(gcbf,'vcross_buttondown');
wbmotion_cross([],[],'v');

%---------------------------------------------------------------
function wbdown_hvcross(hco,eventStruct)
% window button down in hv-crosshair mode
if ~isLeftClick(gcbf), return; end
install_cursorfcns(gcbf,'hvcross_buttondown');
wbmotion_cross([],[],'hv');

%---------------------------------------------------------------
function wbdown_segment(hco,eventStruct)
% window button down in segmentation mode
if ~isLeftClick(gcbf), return; end
install_cursorfcns(gcbf,'segment_buttondown');
wbmotion_segment([],[],gcbf);

%---------------------------------------------------------------
function wbdown_thumb(hco,eventStruct)
% window button down in thumbnail mode
if ~isLeftClick(gcbf), return; end

% cache y-coord of pointer
ud = get(gcbf,'userdata');
hax_time = ud.hax(2);
cp = get(hax_time,'currentpoint');
xdata = get(ud.hthumb,'xdata');
width = max(xdata)-min(xdata);

ud.thumb.origPt = cp(1,1);   % x-coord only
ud.thumb.width  = width;
ud.thumb.xdata  = xdata;
set(gcbf,'userdata',ud);

changePtr(gcbf,'closedhand');
install_cursorfcns(gcbf,'thumb_buttondown');


% Turn off image axis visibility,
% so that it does not flash while panning:
%
% xxx off permanently now:
%set(ud.hax(1),'vis','off');
%
% Turn off crosshair visibility:
set([ud.hspec_y ud.hspec_x ud.htslice_y],'vis','off');

%---------------------------------------------------------------
function wbdown_thumbleft(hco,eventStruct)

% window button down in LEFT thumbnail mode
if ~isLeftClick(gcbf), return; end

% cache y-coord of pointer
ud = get(gcbf,'userdata');
hax_time = ud.hax(2);
cp = get(hax_time,'currentpoint');
xdata = get(ud.hthumb,'xdata');
width = max(xdata)-min(xdata);

ud.thumb.origPt = cp(1,1);   % x-coord only
ud.thumb.width  = width;
ud.thumb.xdata  = xdata;
set(gcbf,'userdata',ud);

install_cursorfcns(gcbf,'thumbleft_buttondown');

% Turn off crosshair visibility:
set([ud.hspec_y ud.hspec_x],'vis','off');

%---------------------------------------------------------------
function wbdown_thumbright(hco,eventStruct)

% window button down in LEFT thumbnail mode
if ~isLeftClick(gcbf), return; end

% cache y-coord of pointer
ud = get(gcbf,'userdata');
hax_time = ud.hax(2);
cp = get(hax_time,'currentpoint');
xdata = get(ud.hthumb,'xdata');
width = max(xdata)-min(xdata);

ud.thumb.origPt = cp(1,1);   % x-coord only
ud.thumb.width  = width;
ud.thumb.xdata  = xdata;
set(gcbf,'userdata',ud);

install_cursorfcns(gcbf,'thumbright_buttondown');

% Turn off crosshair visibility:
set([ud.hspec_y ud.hspec_x],'vis','off');

%----------------------------------------------------
function wbdown_cmap(hco,eventStruct)
% window button down in colormap mode

hfig = gcbf;

% Only allow left (normal) or shift+left (extend)
st = get(hfig,'SelectionType');
i=strmatch(st,{'normal','extend','open'});
if isempty(i), return; end

if i==3,
    % open dynamic range menu
	manual_cmap_limits([],[],hfig);
	return
elseif i==2,
    % Shift+left button = translate,
    % show up/down cursor during drag
    % NOTE: cannot update cursor when shift is pressed
    %       but no mouse button is pressed (no event!)
	changePtr(hfig,'uddrag'); % xxx
end

ud = get(hfig,'userdata');

% cache y-coord of pointer
hax_cbar = ud.hax(5);
cp = get(hax_cbar,'currentpoint');
ud.cbar.origPt = cp(1,2);   % y-coord only
ud.cbar.SelectionType = st; % normal or extend

% The current clim is in the spectrogram image
% We want to know the midpoint of this
orig_dr = get(ud.hax(1),'clim');
ud.cbar.midPt = sum(orig_dr)/2;

% Determine if pointer went down in top or bottom
% half of colorbar:
ud.cbar.StartInTop = (ud.cbar.origPt >= ud.cbar.midPt);

% Cache original dynamic range:
hax_spec = ud.hax(1);
ud.cbar.starting_dr = get(hax_spec,'clim');
set(hfig,'userdata',ud);

install_cursorfcns(hfig,'cmap_buttondown');

% Set initial clim into userdata in case motion
% callback not performed (motion updates userdata).
% wbup_cmap reads the userdata
%
% Turn off visibility during drag to prevent flash
set(hax_cbar, ...
    'userdata',ud.cbar.starting_dr, ...
    'vis','off');

%---------------------------------------------------------------
function wbup_hcross(hco,eventStruct)
% window button up in h-crosshair mode
install_cursorfcns(gcbf,'hcross');
update_cmap_ptr(gcbf);

%---------------------------------------------------------------
function wbup_vcross(hco,eventStruct)
% window button up in v-crosshair mode
install_cursorfcns(gcbf,'vcross');
update_cmap_ptr(gcbf);

%---------------------------------------------------------------
function wbup_hvcross(hco,eventStruct)
% window button up in hv-crosshair mode
install_cursorfcns(gcbf,'hvcross');
update_cmap_ptr(gcbf);

%---------------------------------------------------------------
function wbup_segment(hco,eventStruct)
% window button up in segmentation mode
install_cursorfcns(gcbf,'segment');

%---------------------------------------------------------------
function wbup_cmap(hco,eventStruct)
% window button up in colormap mode
install_cursorfcns(gcbf,'cmap');

% Set new dynamic range limits into spectrogram image
% Note: userdata could be empty if this is the first entry...
ud = get(gcbf,'userdata');
hax_cbar=ud.hax(5);
set(ud.hax(1),'clim',get(hax_cbar,'userdata'));
set(hax_cbar,'vis','on'); % re-enable axis vis

% Set new status msg, since it doesn't update
% in the install_cursorfcns fcn for cmap callbacks
% Do this by calling the general mouse-motion fcn:
wbmotion_general([],[]);

%---------------------------------------------------------------
function update_cmap_ptr(hfig)
% Update colormap pointer:

ud = get(hfig,'userdata');
v = get_spec_val(hfig);  % value in dB
dy_tri = ud.crosshair.cbar.dy_tri;
set(ud.hcmap_arrow,'ydata', [v+dy_tri v-dy_tri v]);


%---------------------------------------------------------------
function [i,j] = get_adjusted_crosshair_idx(hfig)
% Find image matrix coordinate pair (j,i) under crosshair.
% Adjust crosshair for "half-pixel offset" implicit in image display

ud=get(hfig,'userdata');
xc=ud.crosshair.xctr;
yc=ud.crosshair.yctr;
himage=ud.himage;
im=get(himage,'cdata');

% Get image pixel size:
xdata=get(himage,'xdata');
if length(xdata)>1, dx = xdata(2)-xdata(1); else dx=0; end

ydata=get(himage,'ydata');
if length(ydata)>1, dy = ydata(2)-ydata(1); else dy=0; end

% Remove half a pixel size from apparent cursor position:
xc=xc-dx/2;
yc=yc-dy/2;

% Find pixel coordinate under the crosshair:
i=find(xc>=xdata);
if isempty(i), i=1;
else i=i(end)+1;
end
j=find(yc>=ydata);
if isempty(j), j=1;
else j=j(end)+1;
end
sz=size(im);
if i>sz(2), i=sz(2); end
if j>sz(1), j=sz(1); end

%---------------------------------------------------------------
function v = get_spec_val(hfig)

ud    = get(hfig,'userdata');
im    = get(ud.himage,'cdata');
[i,j] = get_adjusted_crosshair_idx(hfig);
v     = double(im(j,i));  % Get pixel value in double-precision

%---------------------------------------------------------------
function v = get_spec_freq(hfig)

ud    = get(hfig,'userdata');
im    = get(ud.himage,'cdata');
[i,j] = get_adjusted_crosshair_idx(hfig);
v     = im(:,i);  % Get pixel row in uint8

%---------------------------------------------------------------
function v = get_spec_tslice(hfig)

ud    = get(hfig,'userdata');
im    = get(ud.himage,'cdata');
[i,j] = get_adjusted_crosshair_idx(hfig);
v     = im(j,:);  % Get pixel column

%---------------------------------------------------------------
function update_time_readout(hfig,diffTime)

% xxx

ud = get(hfig,'userdata');
if nargin<2,
   t=ud.crosshair.xctr;
   prefix='';
else
   t=diffTime - ud.crosshair.xctr;
   prefix='\Deltat ';
end

% Update time readout
[y,e,u] = engunits(t, 'latex','time');
%str=[prefix num2str(y) ' ' u];
str=[prefix sprintf('%.4f',y) ' ' u];
set(ud.htext_time,'string',str);

%---------------------------------------------------------------
function update_freq_readout(hfig,diffFreq)

ud=get(hfig,'userdata');
if nargin<2,
   f=ud.crosshair.yctr;
   prefix='';
else
   f=diffFreq - ud.crosshair.yctr;
   prefix='\Deltaf ';
end

% Update freq readout
[y,e,u] = engunits(f,'latex');
%str=[prefix num2str(y) ' ' u 'Hz'];
str=[prefix sprintf('%.4f',y) ' ' u 'Hz'];
set(ud.htext_freq,'string',str);

%---------------------------------------------------------------
function update_dB_readout(hfig,diffAmpl)

ud = get(hfig,'userdata');
if nargin<2,
   a=get_spec_val(hfig);
   prefix='';
else
   a=diffAmpl - get_spec_val(hfig);
   prefix='\Deltaa=';
end

% Update mag readout
%str=[prefix num2str(a) ' dB'];
str=[prefix sprintf('%.4f',a) ' dB'];
set(ud.htext_mag,'string',str);

%---------------------------------------------------------------
function clear_dB_readout(hfig)

ud = get(hfig,'userdata');
set(ud.htext_mag,'string','');

%---------------------------------------------------------------
function wbmotion_cross(hco,eventStruct,sel)
% motion callback during horiz/vert-crosshair selection
% sel='h', 'v', or 'hv'

% Get current point in axis ASAP:
hfig = gcbf;
hco  = gco;
switch get(hco,'type')
case 'axes'
   hax=hco;
otherwise
   hax=get(hco,'parent');
end

cp   = get(hax,'currentpoint');
ud   = get(hfig,'userdata');
x    = cp(1,1);
y    = cp(1,2);

switch sel
case 'h'
   x=ud.crosshair.xctr;
case 'v'
   y=ud.crosshair.yctr;
end

% Constrain to axis limits, so we don't lose cursor:
if any(sel=='v'),
   xlim=get(hax,'xlim');
   if x<xlim(1),
      x=xlim(1);
   elseif x>xlim(2),
      x=xlim(2);
   end
end

if any(sel=='h'),
   ylim=get(hax,'ylim');
   if y<ylim(1),
      y=ylim(1);
   elseif y>ylim(2),
      y=ylim(2);
   end
end
set_crosshairs(hfig,x,y);

%---------------------------------------------------------------
function wbmotion_segment(hco,eventStruct,hfig)
% motion callback during segmentation selection

% xxx
% Get current point in axis ASAP:
if nargin<3,
   hfig = gcbf;
end

hax=gco;
t=get(hax,'type');
if ~strcmp(t,'axes'),
   hax = get(hax,'parent');
end
cp   = get(hax,'currentpoint');
ud   = get(hfig,'userdata');
x    = cp(1,1);
y    = cp(1,2);

% Constrain to axis limits, so we don't lose cursor:
xlim=get(hax,'xlim');
if x<xlim(1),
   x=xlim(1);
elseif x>xlim(2),
   x=xlim(2);
end
ylim=get(hax,'ylim');
if y<ylim(1),
   y=ylim(1);
elseif y>ylim(2),
   y=ylim(2);
end

update_time_readout(hfig,x);
update_freq_readout(hfig,y);
clear_dB_readout(hfig);

%---------------------------------------------------------------
function install_cursorfcns(hfig,cursorType)

switch lower(cursorType)
case 'none'
   dn     = [];
   motion = [];
   up     = [];
   status = '';
   
case 'general'
   dn     = [];
   motion = @wbmotion_general;
   up     = [];
   status = 'Ready';
   
case 'segment'
   dn     = @wbdown_segment;
   motion = @wbmotion_general;
   up     = [];
   status = 'Ready';
   
case 'segment_buttondown'
   dn     = [];
   motion = @wbmotion_segment;
   up     = @wbup_segment;
   status = 'Difference from crosshair';
   
case 'thumb'
   % button not pushed, thumbnail highlighted
   dn     = @wbdown_thumb;
   motion = @wbmotion_general;
   up     = [];
   status = 'Pan zoom window';
   
case 'thumb_buttondown'
   % button pushed, thumbnail highlighted
   dn     = [];
   motion = @wbmotion_thumb;
   up     = @wbup_thumb;
   status = 'Release to set zoom window';
   
case 'thumbleft'
   % button not pushed, left thumbnail edge highlighted
   dn     = @wbdown_thumbleft;
   motion = @wbmotion_general;
   up     = [];
   status = 'Adjust zoom window left edge';
   
case 'thumbleft_buttondown'
   % button pushed, thumbnail highlighted
   dn     = [];
   motion = @wbmotion_thumbleft;
   up     = @wbup_thumbleft;
   status = 'Release to set zoom window';
   
case 'thumbright'
   % button not pushed, right thumbnail edge highlighted
   dn     = @wbdown_thumbright;
   motion = @wbmotion_general;
   up     = [];
   status = 'Adjust zoom window right edge';
   
case 'thumbright_buttondown'
   % button pushed, right thumbnail edge highlighted
   dn     = [];
   motion = @wbmotion_thumbright;
   up     = @wbup_thumbright;
   status = 'Release to set zoom window';
   
case 'hcross'
   % button not pushed, h-crosshair highlighted
   dn     = @wbdown_hcross;
   motion = @wbmotion_general;
   up     = [];
   status = 'Move horizontal cursor';
   
case 'hcross_buttondown'
   % button pushed while over horiz cross-hair
   dn     = [];
   motion = {@wbmotion_cross,'h'};
   up     = @wbup_hcross;
   status = 'Release to update cursor';
   
case 'vcross'
   dn     = @wbdown_vcross;
   motion = @wbmotion_general;
   up     = [];
   status = 'Move vertical cursor';
   
case 'vcross_buttondown'
   dn     = [];
   motion = {@wbmotion_cross,'v'};
   up     = @wbup_vcross;
   status = 'Release to update cursor';
   
case 'hvcross'
   dn     = @wbdown_hvcross;
   motion = @wbmotion_general;
   up     = [];
   status = 'Move crosshair cursor';
   
case 'hvcross_buttondown'
   dn     = [];
   motion = {@wbmotion_cross,'hv'};
   up     = @wbup_hvcross;
   status = 'Release to update cursor';
   
% Change dynamic range of colormap
case 'cmap'
   dn     = @wbdown_cmap;
   motion = @wbmotion_general;
   up     = [];
   % Status is set in wbmotion_general function
   % since it depends on which pointer we're using
   status = -1;
   
case 'cmap_buttondown'
   dn     = [];
   motion = @wbmotion_cmap;
   up     = @wbup_cmap;
   status = 'Release to update colormap';
   
otherwise
   error('Unrecognized cursorfcn');
end

set(hfig, ...
   'windowbuttondownfcn',  dn, ...
   'windowbuttonmotionfcn',motion, ...
   'windowbuttonupfcn',    up)

update_status(hfig,status);


%---------------------------------------------------------------
function resize_fig(hco,eventStruct)
% Callback to resize the figure

update_axes_with_eng_units(gcbf);


%---------------------------------------------------------------
function update_axes_with_eng_units(hfig)

% Update the tick marks for axes that are using engineering units
% For example, a resize could have added or removed ticks, and the
% axes would no longer have the proper tick marks
ud       = get(hfig,'userdata');
hax_time = ud.hax(2);
hax_freq = ud.hax(4);

% Update freq-axis labels for engineering units, etc:
yy=get(hax_freq,'ytick');
[cs,eu] = convert2engstrs(yy);
set(hax_freq,'yticklabel',cs);
set(get(hax_freq,'ylabel'),'string',['Frequency, ' eu 'Hz']);

% Update time-axis labels for engineering units, etc:
yy=get(hax_time,'xtick');
[cs,eu] = convert2engstrs(yy,'time');
set(hax_time,'xticklabel',cs);
set(get(hax_time,'xlabel'),'string',['Time, ' eu]);


%---------------------------------------------------------------
function update_gui(hco, eventStruct, hfig)

if nargin<3, hfig=gcbf; end

ptr.ptr = get(hfig,'pointer');
ptr.shape = get(hfig,'pointershapecdata');
ptr.hot = get(hfig,'pointershapehotspot');
setptr(hfig,'watch');  % set user's expectations...

ud = get(hfig,'userdata');
hax_spec     = ud.hax(1);
hax_time     = ud.hax(2);
hax_tslice   = ud.hax(3);
hax_freq     = ud.hax(4);
hax_cbar     = ud.hax(5);
hax_cbar_ind = ud.hax(6);

% Get spectrogram parameters:
Nwin = str2double(get(ud.spect.nwin,'string'));
Nlap = str2double(get(ud.spect.nlap,'string'));
Nfft = str2double(get(ud.spect.nfft,'string'));

% Recompute spectrogram
y      = ud.y;
Fs     = ud.Fs;
window = 'blackman';
w = feval(window,Nwin,'periodic');
try
   [b,f,t]=specgram(y,Nfft,Fs,w,Nlap);
   [Pxx, W] = pwelch(y,w,Nlap,Nfft,Fs); 
catch
   % Error occurred
   % Put up modal error display, then
   % get spectrogram params from cache (userdata)
   msg = lasterr;
   errordlg(msg,'Specgram Demo Error','modal');
   
   % Reset Nwin/Nlap/Nfft:
   Nwin = get(ud.spect.nwin,'userdata');
   Nlap = get(ud.spect.nlap,'userdata');
   Nfft = get(ud.spect.nfft,'userdata');
   set(ud.spect.nwin,'string',num2str(Nwin));
   set(ud.spect.nlap,'string',num2str(Nlap));
   set(ud.spect.nfft,'string',num2str(Nfft));
   return
end

% Update new values into "old" cache (userdata field)
% Also, update strings themselves, in case spaces have
% been removed, etc:
set(ud.spect.nwin,'string',num2str(Nwin),'userdata',Nwin);
set(ud.spect.nlap,'string',num2str(Nlap),'userdata',Nlap);
set(ud.spect.nfft,'string',num2str(Nfft),'userdata',Nfft);

ud.f = f;
ud.t = t;

% Pxx is the distribution of power per unit frequency.
ud.Pxx = Pxx;

% W is the vector of normalized frequencies at which the PSD is estimated.
ud.w = W; 

% Carefully execute log10:
wstate=warning;
warning off;
b = 20*log10(abs(b));
warning(wstate);

% Handle -inf's:
i_inf = find(isinf(b(:)));
if ~isempty(i_inf),
   % Set all -inf points to next-lowest value:
   b(i_inf)=inf;
   min_val=min(b(:));
   b(i_inf)=min_val;
end

blim = [min(b(:)) max(b(:))];
spec_xlim = [0 max(t)];
spec_ylim = [0 max(f)];

% Update spectrogram
% XXX UINT8 change:
set(ud.himage,'cdata',b, 'xdata',t, 'ydata',f);
%set(ud.himage,'cdata',uint8( (b-blim(1))./(blim(2)-blim(1))*255 + 1 ), 'xdata',t, 'ydata',f);
set(hax_spec,'xlim',spec_xlim, 'ylim', spec_ylim);

% Update colorbar
%XXX UINT8 change:
set(ud.himage_cbar, 'ydata',blim, 'cdata', (1:256)');
%set(ud.himage_cbar, 'ydata',[1 256], 'cdata', (1:256)');
set(hax_cbar,'ylim',blim);
set(hax_cbar_ind, 'ylim',blim);

% Update time slice
rows=size(b,1);
bi=floor(rows/2); if bi<1, bi=1; end
set(ud.htslice_line,'xdata',t, 'ydata',b(bi,:));
set(hax_tslice, 'xlim',spec_xlim, 'ylim',blim);
% Use 2 ticks only 
new_ticks = return2ticks(hax_tslice);
set(hax_tslice,'Ytick',new_ticks);

% frequency slice
cols=size(b,2);
bj=floor(cols/2); if bj<1, bj=1; end
set(ud.hfreq_line, 'xdata',b(:,bj),'ydata',f);
set(hax_freq, 'ylim',spec_ylim,'xlim',blim);

% Use 2 ticks only 
new_xticks = return2ticks(ud.hax(4));
set(ud.hax(4),'Xtick',new_xticks);
	
	
% full time trace
ylen=length(y);
half_nfft = ceil(Nfft/2);
t1=(0 : length(y)-half_nfft)/Fs;
set(ud.htime_plot,'xdata',t1,'ydata',y(half_nfft:end));
set(hax_time, 'xlim',spec_xlim);

update_axes_with_eng_units(hfig);

% setup thumbnail patch
axylim = get(hax_time,'ylim');
ymax = axylim(2);
ymin = axylim(1);
tmax = max(t);
tmin = min(t);
set(ud.hthumb, ...
   'xdata',[tmin tmax tmax tmin tmin], ...
   'ydata',[ymin ymin ymax ymax ymin]);

% Reset crosshair positions
crosshair      = ud.crosshair;
crosshair.xctr = mean(spec_xlim);
crosshair.yctr = mean(spec_ylim);
time_ylim      = get(hax_time,'ylim');
freq_xlim      = get(hax_freq,'xlim');
tslice_ylim    = get(hax_tslice,'ylim');

% Crosshairs:
set(ud.hspec_x, ...
   'xdata',spec_xlim, ...
   'ydata',[crosshair.yctr crosshair.yctr]);
set(ud.hspec_y, ...
   'xdata',[crosshair.xctr crosshair.xctr], ...
   'ydata',spec_ylim);
set(ud.htime_y, ...
   'xdata',[crosshair.xctr crosshair.xctr], ...
   'ydata',time_ylim);
set(ud.htslice_y, ...
   'xdata',[crosshair.xctr crosshair.xctr], ...
   'ydata',tslice_ylim);
set(ud.hfreq_x, ...
   'xdata',freq_xlim, ...
   'ydata',[crosshair.yctr crosshair.yctr]);

% Colormap indicator triangle:
dy_tri=.025*diff(blim);
yp=b(bi,bj);
ytri=[yp+dy_tri yp-dy_tri yp ];
set(ud.hcmap_arrow, ...
   'erase','xor', ...
   'linestyle','none', ...
   'xdata',[0 0 1], ...
   'ydata',ytri);
crosshair.cbar.dy_tri = dy_tri;

% Update user data:
ud.crosshair = crosshair;
set(hfig,'userdata',ud);   

% Text readouts:
update_time_readout(hfig);
update_freq_readout(hfig);
update_dB_readout(hfig);
%xxx
%str=[num2str(b(bi,bj)) ' dB'];
%set(ud.htext_mag,'string',str);

% Re-establish pointer cursor, etc:
set(hfig,'pointer',ptr.ptr, ...
   'pointershapecdata',ptr.shape, ...
   'pointershapehotspot',ptr.hot);

%---------------------------------------------------------------
function printdlg_cb(hco,eventStruct)
printdlg(gcbf);

%---------------------------------------------------------------
function printpreview_cb(hco,eventStruct)
printpreview(gcbf);

%---------------------------------------------------------------
function close_cb(hco,eventStruct)
close(gcbf);

%---------------------------------------------------------------
function hfig=create_gui(y,Fs,tmin,tmax)
%CREATE_GUI Render the figure and all uicontrols.

% freq, specgram and time
hfig = figure('numbertitle','off', ...
   'name','Spectrogram Demo', ...
   'menubar','none', ...
   'toolbar','none', ...
   'resizefcn',@resize_fig, ...
   'doublebuffer','off', ...
   'backingstore','off', ...
   'integerhandle','off', ...
   'vis','off', ...
   'pos',[50 15 550 450],...
   'PaperPositionMode','auto');

% Try to create audioplayer object for audio playback and tracking cursor
audioplayer_enabled = true;
try
    player = audioplayer(y / abs(max(y)), Fs);  %make a player for the normalized signal
    set(player, 'UserData', hfig, 'TimerPeriod', 0.05, 'TimerFcn', @update_audio_position, ...
        'StartFcn', @start_function);
    % the toolbar callback fcns look for these named bits of appdata 
    setappdata(hfig, 'theAudioPlayer', player); 
    setappdata(hfig, 'theAudioRecorder', []);
    selection.inPoint = tmin*Fs;
    selection.outPoint = tmax*Fs;
    setappdata(hfig, 'audioSelection', selection); % selection starts as "full"
catch
    audioplayer_enabled = false;
end

% Load toolbar icons
icon_file = 'specgramdemoicons.mat';
icon = load(icon_file);

% Create toolbar:
htoolbar = uitoolbar(hfig);

% Print:
uipushtool('parent',htoolbar, ...
   'tooltip','Print', ...
   'clickedcallback',@printdlg_cb, ...
   'cdata',icon.print);
% Print preview:
uipushtool('parent',htoolbar, ...
   'tooltip','Print Preview', ...
   'clickedcallback',@printpreview_cb, ...
   'cdata',icon.printpreview);

if audioplayer_enabled,
    % add Play/Pause/Stop audio toolbar buttons
    [htoolbar, audiobuttons] = render_basicaudiotoolbar(htoolbar);
    
    % set play button to "active" version, because changing the button image
    % causes the whole darn window to repaint!  Ick.
    play_button = audiobuttons(1);
    audioIcons = getappdata(htoolbar, 'audioButtonIcons');
    set(play_button, 'cdata', audioIcons.play_on);
else
    % Play icon
    uipushtool('parent',htoolbar, ...
        'tooltip','Play', ...
        'clickedcallback',@play_sound, ...
        'cdata',icon.playsound);
end

% Zoom in, out, full
uipushtool('parent',htoolbar, ...
   'separator','on', ...
   'tooltip','Zoom 100%', ...
   'clickedcallback', @zoom_full, ...
   'cdata',icon.fullview);
uipushtool('parent',htoolbar, ...
   'tooltip','Zoom In', ...
   'clickedcallback',@zoom_in, ...
   'cdata',icon.zoominx);
uipushtool('parent',htoolbar, ...
   'tooltip','Zoom Out', ...
   'clickedcallback',@zoom_out, ...
   'cdata',icon.zoomoutx);
% Center crosshairs
uipushtool('parent',htoolbar, ...
   'tooltip','Center Crosshair', ...
   'clickedcallback',@center_cross, ...
   'separator','on', ...
   'cdata',icon.center_crosshair);

% What's this?
uipushtool('parent',htoolbar, ...
   'separator','on', ...
   'tooltip','What''s This?', ...
   'clickedcallback',@HelpWhatsThisCB, ...
   'cdata',icon.whatsthis);

% specgram
% inputs: t, f, b
hax_spec = axes('pos',[.25 .275 .625 .525]);
himage=image; axis xy; colormap(jet)
set(himage,'erase','xor','cdatamapping','scaled');
set(hax_spec, ...
   'box','on', ...
   'draw','fast', ...
   'xticklabel','');
% xxx
% Shut off image axis visibility
set(hax_spec, 'vis','off');

% time slice
hax_tslice = axes('pos',[.25 .825 .625 .1]);
htslice_line=line('color','b');
set(htslice_line,'erase','xor'); % xxx
set(hax_tslice, ...
   'box','on', ...
   'fontsize',8, ...
   'draw','fast', ...
   'xticklabel','', ...
   'xtick',[],  ...
   'yaxisloc','right');
ylabel('dB');
sz=size(y);

% Title of time slice plot
[ey,ee,eu]=engunits(Fs,'latex');
str=['Data=[' num2str(sz(1)) 'x' num2str(sz(2)) '], Fs=' ...
      num2str(ey) ' ' eu 'Hz'];
title(str);

% colorbar
cmapLen = 256;
hax_cbar = axes('pos',[.91 .275 .03 .525]);
himage_cbar = image([0 1],[0 1],(1:cmapLen)');
set(himage_cbar,'cdatamapping','scaled','erase','none');
set(hax_cbar, ...
   'draw','fast', ...
   'fontsize',8, ...
   'box','on', ...
   'xticklabel','', ...
   'Ydir','normal', 'YAxisLocation','right', 'xtick',[]);

% frequency slice
hax_freq = axes('pos',[.1 .275 .125 .525]);
hfreq_line=line('color','b');
set(hfreq_line,'erase','xor');
set(hax_freq, ...
   'fontsize',8, ...
   'box','on',...
   'draw','fast', ...
   'xdir','rev', ...
   'xaxisloc','top');
ylabel('Frequency, Hz');
xlabel('dB');

% colorbar indicator
hax_cbar_ind = axes('pos',[.885+.01 .275 .015 .525]);
set(hax_cbar_ind,'vis','off','xlim',[0 1],'ylim',[0 1], ...
   'draw','fast', ...
   'fontsize',8, ...
   'yaxisloc','right');

% full time trace
% inputs: y, Fs
hax_time = axes('pos',[.25 .15 .625 .1]);
htime_plot = line('color','b');
set(hax_time, ...
   'box','on',...
   'fontsize',8, ...
   'draw','fast', ...
   'yaxisloc','right');
xlabel('Time, secs'); ylabel('Ampl');

% thumbnail patch
%bgclr = get(0,'defaultuicontrolbackgr');
%bgclr = get(0,'defaultfigurecolor');
bgclr = 'b';
hthumb = patch([0 0 1 1 0], [0 1 1 0 0], bgclr, ...
   'edgecolor','k', ...
   'erase','xor');

% Crosshairs:
hspec_x=line('parent',hax_spec, ...
   'erase','xor');
hspec_y=line('parent',hax_spec, ...
   'erase','xor');
htime_y=line('parent',hax_time, ...
   'linewidth',2, ...
   'erase','xor');
htslice_y=line('parent',hax_tslice, ...
   'erase','xor');
hfreq_x=line('parent',hax_freq, ...
   'erase','xor');

% Colormap indicator triangle:
hcmap_arrow=patch('parent',hax_cbar_ind, ...
   'xdata',[0 0 1], ...
   'ydata',[0 0 0]);

% Text readouts:
% xxx
hax_readout = axes('pos',[0.02 .09 .185 .15],'vis','off');
patch([0 1 1 0 0],[0 0 1 1 0],'w');
htext_time = text('parent',hax_readout, 'pos',[0.075 .8], ...
   'erase','xor');
htext_freq = text('parent',hax_readout, 'pos',[0.075 .5], ...
   'erase','xor');
htext_mag = text('parent',hax_readout, 'pos',[0.075 .2], ...
   'erase','xor');

% Status bar
bgc=get(hfig,'color');
hax_status = axes('pos',[0.005 0.01 .99 .04]);
set(hax_status,'vis','off','xlim',[0 1],'ylim',[0 1]);
% Main status:
h1=line([0 .45 .45],[0 0 1],'color','w');
h2=line([0 0 .45],[0 1 1],'color',[1 1 1]*0);
htext_status = uicontrol('parent',hfig, ...
   'style','text', ...
   'units','norm', ...
   'pos',[.015 .012 .96-.55 .035], ...
   'horiz','left', ...
   'backgr',bgc, ...
   'string','Ready');

% Spectrogram controls:
%
% segment length
ylen = length(y);
Nfft = min(256,ylen);
Nwin = Nfft;
% Nlap = min(Nwin,ceil(Nwin/2));
Nlap = min(Nwin,200);
ud.spect.nwin_text = uicontrol('parent',hfig, ...
   'style','text', ...
   'units','norm', ...
   'pos', [.45 .012 .07 .035], ...
   'backgr',bgc, ...
   'horiz','right', ...
   'string','Nwin:');
ud.spect.nwin = uicontrol('parent',hfig, ...
   'style','edit', ...
   'units','norm', ...
   'pos', [.45+.07+.005 .01 .08 .04], ...
   'backgr','white', ...
   'horiz','left', ...
   'string',num2str(Nwin), ...
   'callback',@update_gui);
% overlap length
ud.spect.nlap_text = uicontrol('parent',hfig, ...
   'style','text', ...
   'units','norm', ...
   'pos', [.61 .012 .06 .035], ...
   'backgr',bgc, ...
   'horiz','right', ...
   'string','Nlap:');
ud.spect.nlap = uicontrol('parent',hfig, ...
   'style','edit', ...
   'units','norm', ...
   'pos', [.61+.06+.005 .01 .08 .04], ...
   'backgr','white', ...
   'horiz','left', ...
   'string',num2str(Nlap), ...
   'callback',@update_gui);
% fft length
ud.spect.nfft_text = uicontrol('parent',hfig, ...
   'style','text', ...
   'units','norm', ...
   'pos', [.76 .012 .05 .035], ...
   'backgr', bgc, ...
   'horiz','right', ...
   'string','Nfft:');
ud.spect.nfft = uicontrol('parent',hfig, ...
   'style','edit', ...
   'units','norm', ...
   'pos', [.75+.06+.005 .01 .08 .04], ...
   'backgr','white', ...
   'horiz','left', ...
   'string',num2str(Nfft), ...
   'callback',@update_gui);

% Window

% Menus
mFile = uimenu('parent',hfig,'label','&File');
uimenu('parent',mFile,'label','&Print','callback',@printdlg_cb);
uimenu('parent',mFile,'label','&Close', ...
   'callback',@close_cb,'separator','on');

uimenu('parent',hfig, 'label','&Window', ...
   'tag','winmenu', ...
   'callback', winmenu('callback'));
%
% Help menu:
%
mHelp = uimenu('parent',hfig,'label','&Help');

% Help -> Specgramdemo Help 
uimenu('parent',mHelp, ...
   'Label','Spectrogram Demo &Help', ...
   'Callback',@HelpSpecgramdemoCB);

% Help -> Signal Processing Toolbox Help
uimenu('parent',mHelp, ...
   'Label','Signal Processing &Toolbox Help', ...
   'Callback',@HelpProductCB);

% Help -> What's This?
uimenu('parent',mHelp, ...
   'Label','&What''s This?', ...
   'Callback', @HelpWhatsThisCB,...
   'Separator','On');

% Help -> Demos
uimenu('parent',mHelp, ...
   'Label','&Demos', ...
   'Callback',@HelpDemosCB,...
   'Separator','On');

% Help -> About Signal Processing Toolbox
uimenu('parent',mHelp, ...
   'Label','&About Signal Processing Toolbox', ...
   'Callback',@HelpAboutCB,...
   'Separator','On');

set(hfig,'colormap',jet(256));

% Retain info in figure userdata:
ud.hfig        = hfig;
ud.hax         = [hax_spec hax_time hax_tslice hax_freq hax_cbar hax_cbar_ind];
ud.hspec_x     = hspec_x;
ud.hspec_y     = hspec_y;
ud.htime_y     = htime_y;
ud.htslice_y   = htslice_y;
ud.hfreq_x     = hfreq_x;
ud.hcmap_arrow = hcmap_arrow;
ud.hfreq_line  = hfreq_line;
ud.htslice_line  = htslice_line;
ud.htime_plot  = htime_plot;
ud.htext_time  = htext_time;
ud.htext_freq  = htext_freq;
ud.htext_mag   = htext_mag;
ud.htext_status= htext_status;
ud.crosshair   = [];
ud.himage      = himage;
ud.himage_cbar = himage_cbar;
ud.hthumb      = hthumb;
ud.f=[];
ud.t=[];
ud.y=y;
ud.Fs=Fs;
ud.currPtr = '';  % current pointer
ud.Pxx = [];
ud.w = [];

% Set plot default modes:
ud.plot.top  = 'spectrogram_time_slice';  
ud.plot.left = 'spectrogram_freq_slice';

set(hfig,'userdata',ud);

winmenu(hfig);  % Initialize the submenu, after ud is installed

% Protect GUI from user plots, etc:
set([hfig ud.hax],'handlevis','callback');

% After GUI has all elements in it, install context help:
install_context_help(hfig);
install_context_menus(hfig);

% Populate GUI with data, limits, etc:
update_gui([],[],hfig);

% Enable general (non-segmenting) mouse functions:
install_cursorfcns(hfig,'general');
set(hfig,'vis','on');

%%%%%%%%%%%%%%%%%%%%%%%%%%
% inserted by S.Bleeck
% switch to modal
uiwait(hfig);
%%%%%%%%%%%%%%%%%%%%%%%%%%



return

% ---------------------------------------------------------------
% H E L P    S Y S T E M
% --------------------------------------------------------------
%
% General rules:
%  - Context menus that launch the "What's This?" item have their
%    tag set to 'WT?...', where the '...' is the "keyword" for the
%    help lookup system.
%

%--------------------------------------------------------------
function HelpWhatsThisBDown(hco,eventStruct)
% HelpWhatsThisBDown Button-down function called from either
%   the menu-based "What's This?" function, or the toolbar icon.

hfig = gcbf;
hOver = gcbo; % overobj('uicontrol');  % handle to object under pointer

% Restore pointer icon quickly:
setptr(hfig,'arrow');

% Shut off button-down functions for uicontrols and the figure:
hChildren = findobj(hfig);
set(hChildren, 'ButtonDownFcn','');
set(hfig,'WindowButtonDownFcn','');

% Restore GUI pointers, etc:
wbmotion_general(hfig);

% Dispatch to context help:
hc = get(hOver,'uicontextmenu');
hm = get(hc,'children');  % menu(s) pointed to by context menu

% Multiple entries (children) of context-menu may be present
% Tag is a string, but we may get a cell-array of strings if
% multiple context menus are present:
% Find 'What's This?' help entry
tag = get(hm,'tag');
helpIdx = find(strncmp(tag,'WT?',3));
if ~isempty(helpIdx),
    % in case there were accidentally multiple 'WT?' entries,
    % take the first (and hopefully, the only) index:
    if iscell(tag),
	    tag = tag{helpIdx(1)};
    end
	HelpGeneral([],[],tag);
end

%--------------------------------------------------------------
function HelpWhatsThisCB(hco, eventStruct)
% HelpWhatsThisCB Get "What's This?" help
%   This mimics the context-menu help selection, but allows
%   cursor-selection of the help topic

% NOTE: Enabling context-help "destroys" the enable-state
%  of all uicontrols in the GUI.  When the callback completes,
%  we must restore the enable states.

hfig = gcbf;

% Change pointer icon:
setptr(hfig,'help');

% Install button-down functions on all uicontrols,
%  plus the figure itself:
% uicontrol, axes, line, patch, text
hChildren = findobj(hfig);
% No need to set enable states, etc.
set(hChildren, ...
   'ButtonDownFcn',@HelpWhatsThisBDown);
set(hfig, ...
   'WindowButtonMotionFcn','', ...
   'WindowButtonUpFcn','', ...
   'WindowButtonDownFcn','');

%--------------------------------------------------------------
function HelpSpecgramdemoCB(hco,eventStruct)
%HELPSPECGRAMDEMO Get specgramdemo reference-page help

helpwin(mfilename);

%--------------------------------------------------------------
function HelpProductCB(hco,eventStruct)
%HELPRPODUCTCB Opens the Help window with the online doc Roadmap
%              page (a.k.a. "product page") displayed.
doc signal/

%--------------------------------------------------------------
function HelpDemosCB(hco,eventStruct)
%HELPDEMOSCB Starts Demo window, with the appropriate product's
%            demo highlighted in the Demo window contents pane.
demo toolbox signal

%--------------------------------------------------------------
function HelpAboutCB(hco,eventStruct)
%HELPABOUTCB Displays version number of product, and copyright.

aboutsignaltbx;

%--------------------------------------------------------------
function HelpGeneral(hco,eventStruct,tag)
% HelpGeneral Define CSH text for specgramdemo

hfig = gcbf;
hco = gcbo;

if nargin<3,
    % Testing purposes only:
   tag = get(hco,'tag');
end

% Check for legal tag string:
if ~ischar(tag),
   error('Invalid context-sensitive help tag.');
end

% Remove 'WT?' prefix;
if strncmp(tag,'WT?',3),
    tag(1:3) = [];
else
    error('Help tag must be a string beginning with "WT?" prefix.');
end

ud = get(hfig,'UserData');

% Define text for CSH system
title = ['Help: ' tag];
msg = '';
switch tag
case ''
   msg = {'';
      'No help available on selected item.'};
  
case 'Spectrogram image'
   msg = {'';
      'This image displays the spectrogram for the signal currently loaded ';
	  'in the viewer.  The spectrogram presents the magnitude of the short-time ';
	  'Fourier transform.';
	  '';
	  'Calculate the spectrogram as follows:';
	  '';
	  '1. Split the signal into overlapping sections and apply the';
	  'window specified by the window parameter to each section.';
	  '';
	  '2. Compute the discrete-time Fourier transform of each';
	  'section with a length Nfft FFT to estimate the short-term ';
	  'frequency content of the signal. These transforms ';
	  'make up the columns of B. The quantity (length(Nwin) - Nlap)'
	  'specifies by how many samples the window will be shifted.';
	  '';
	  '3. For real input, truncate the spectrogram to the';
	  'first (Nfft/2 + 1) points when Nfft is even and (Nfft + 1)/2 when ';
	  'Nfft is odd.'};
  
case 'Zoom Window Panner'
   msg = {'';
      'Shows a panoramic view of the signal which is loaded in the viewer. ';
	  'When you zoom in the spectrogram, the corresponding time domain ';
	  'portion is highlighed.';
	  '';
      'You can zoom the panner by dragging the mouse on the left- and ';
	  'right-hand edges of the highlighted zoom region.  Right-click the ';
	  'highlighted zoom area to bring up a menu for focusing in on the zoomed ';
	  'region'};	  
  
case 'Spectrogram Frequency Slice' % Left axes
	if strcmp(ud.plot.left,'spectrogram_freq_slice'),
		msg = {'';
			'This view displays a frequency slice for the current spectrogram. The ';
			'view is updated as you move the crosshair cursor along the frequency '
			'axes (horizontally).'};
	else
		% Change the helpwin title for the PSD case.
		title = ['Help: Signal Power Spectral Density'];
		
		msg = {'';
			'Displays the Power Spectral Density (PSD) estimate calculated ';
			'using Welch''s averaged modified periodogram method.'};
		
	end
	
case 'Spectrogram Time Slice', % Top axes
	msg = {'';
		'This view displays a time slice for the current spectrogram.  The';
		'view is updated as you move the crosshair cursor along the time'
		'axes (vertically).'};
	
case 'Colorbar'
   msg = {'';
      'The colorbar shows the color scale for the current spectrogram.';
	  ''};
  
case 'Status Bar',
	   msg = {'';
      'The Status Bar displays information about the state of the ';
	  'Spectrogram Demo, the current operation of the tool, and operation';
	  'of the crosshair cursor.'};

case 'Magnitude Readout', 
	   msg = {'';
      'Displays the magnitude (in dB) of a spectrogram slice.';
	  ''};

case 'Frequency Readout',
	   msg = {'';
      'Displays frequency values in Hz.';
	  ''};

case 'Time Readout',
	   msg = {'';
      'Displays time measurements in seconds for the Time Plot ';
	  'and the Time Slice'};

case 'Time Plot', % Bottom axes
	   msg = {'';
      'Time Plot displays the original signal in its entirety.'};
  
case 'Colorbar Indicator',
	   msg = {'';
      'The colorbar indicator points to the level of the spectrogram.'};

case 'Frequency Crosshair',
	   msg = {'';
      'Move the frequency crosshair cursor to pin-point a particular ';
	  'frequency location on the spectrogram''s frequency slice axes.'};

case 'Time Crosshair',
	   msg = {'';
      'Move the time crosshair cursor to pin-point a particular ';
	  'time instance on the spectrogram''s time slice axes.'};

case 'Spectrogram Demo',
	   msg = {'';
      'This is the Spectrogram Demo which displays a spectrogram, ';
	  'a time plot, and a frequency slice of an input signal';
	  '';
	  'SPECGRAMDEMO(y,Fs) displays a spectrogram of signal y, assuming a sample ';
	  'rate of Fs Hz.  If y is specified but Fs is not, a sample rate of 1 ';
	  'Hz is assumed.  If no input arguments are supplied, y and Fs are ';
	  'taken from the default data file "mtlb.mat."'};
  
case 'Spectrogram Window Size',
	   msg = {'';
      'Nwin specifies the length of the Periodic Blackman window used in ';
	  'this demo. The default value is 256.'};
	  
case 'Spectrogram FFT Size',
	   msg = {'';
      'Nfft specifies the FFT length used to calculate the spectrogram. ';
	  'This value determines the frequencies at which the discrete-time ';
	  'Fourier transform is computed. These values are typically powers ';
	  'of two, such as 256 or 512.'};

case 'Spectrogram Overlap'
	   msg = {'';
      'Use Nlap to specify the number of samples to overlap the windowed sections.'};
end

% If no text is defined, simply display the tag.
if isempty(msg),
   msg = {'';
      ['This is the ' tag '.']};
end

% Put up message box for help:
%hmsg = msgbox(msg,title, 'help','modal');
%CenterFigOnFig(hfig, hmsg);

helpwin(char(msg),title);

%--------------------------------------------------------------
function CenterFigOnFig(hfig,hmsg)
% CenterFigOnFig Center hMsg figure on top of hFig figure

set(hfig,'units','pix');
figPos = get(hfig,'pos');
figCtr = [figPos(1)+figPos(3)/2 figPos(2)+figPos(4)/2];

set(hmsg,'units','pix');
msgPos = get(hmsg,'position');
msgCtr = [msgPos(1)+msgPos(3)/2 msgPos(2)+msgPos(4)/2];

movePos = figCtr - msgCtr;

new_msgPos = msgPos;
new_msgPos(1:2) = msgPos(1:2) + movePos;
set(hmsg,'Position',new_msgPos);

return

%--------------------------------------------------------------
function install_context_help(hfig)

ud = get(hfig,'userdata');

main = {'label','&What''s This?',  ...
        'callback',@HelpGeneral, 'parent'};

setWTC(hfig,main, [ud.himage ud.hax(1)], 'Spectrogram image');
setWTC(hfig,main, ud.hthumb, 'Zoom Window Panner');
setWTC(hfig,main, [ud.himage_cbar ud.hax(5)], 'Colorbar');
setWTC(hfig,main, ud.htext_status, 'Status Bar');
setWTC(hfig,main, ud.htext_mag, 'Magnitude Readout');
setWTC(hfig,main, ud.htext_freq, 'Frequency Readout');
setWTC(hfig,main, ud.htext_time, 'Time Readout');
setWTC(hfig,main, [ud.htime_plot ud.hax(2)], 'Time Plot');
setWTC(hfig,main, [ud.htslice_line ud.hax(3)], 'Spectrogram Time Slice');
setWTC(hfig,main, [ud.hfreq_line ud.hax(4)], 'Spectrogram Frequency Slice');
setWTC(hfig,main, [ud.hcmap_arrow ud.hax(6)], 'Colorbar Indicator');

setWTC(hfig,main, [ud.hfreq_x ud.hspec_x], 'Frequency Crosshair');
setWTC(hfig,main, [ud.htime_y ud.htslice_y ud.hspec_y], 'Time Crosshair');
setWTC(hfig,main, ud.hfig, 'Spectrogram Demo');

setWTC(hfig,main, [ud.spect.nwin ud.spect.nwin_text], 'Spectrogram Window Size');
setWTC(hfig,main, [ud.spect.nfft ud.spect.nfft_text], 'Spectrogram FFT Size');
setWTC(hfig,main, [ud.spect.nlap ud.spect.nlap_text], 'Spectrogram Overlap');

% xxx set context for:
% - readout axis
% - uitoolbar

%--------------------------------------------------------------
function setWTC(hfig,main,hItem,tagStr)
% setWT Set the "What's This?" context menu and callback:
hc = uicontextmenu('parent',hfig);
uimenu(main{:},hc, 'tag',['WT?' tagStr]);
set(hItem,'uicontextmenu',hc);


% ---------------------------------------------------------------
% C O N T E X T   M E N U S
% --------------------------------------------------------------

%-----------------------------------------------------------------
function install_context_menus(hfig)

install_specgram_mode_menus(hfig);
install_colorbar_menus(hfig);
install_freq_slice_menus(hfig);
install_time_slice_menus(hfig);
install_time_panner_menus(hfig);

%-----------------------------------------------------------------
function install_specgram_mode_menus(hfig)

% Additional menus to prepend to the spectrogram context menu:

ud = get(hfig,'userdata');
hc = get(ud.himage,'uicontext');  % ud.hax(1) also?

hEntry=[];  % holds handles to each colormap menu item
opts={hc,'2-D Image',@changeSpecgramMode, 'checked','on'};
hEntry(end+1) = createContext(opts);
opts={hc,'3-D Magnitude Plot',@changeSpecgramMode};
hEntry(end+1) = createContext(opts);
% xxx disable last menu until feature implemented:
set(hEntry(end),'enable','off');
opts={hc,'3-D dB Plot',@changeSpecgramMode};
hEntry(end+1) = createContext(opts);
% xxx disable last menu until feature implemented:
set(hEntry(end),'enable','off');

% Give each menu item a vector of handles to all peer menus
set(hEntry,'userdata',hEntry);

fixup_context_order(hc);

%-----------------------------------------------------------------
function install_colorbar_menus(hfig)
% Additional menus to prepend to the colorbar context menu:

ud = get(hfig,'userdata');
hc = get(ud.himage_cbar,'uicontext');  % ud.hax(1) also?

opts={hc,'Colormap',''};
hCmap = createContext(opts);

hEntry=[];  % holds handles to each colormap menu item
opts={hCmap,'Jet',@changeCMap, 'checked','on'};
hEntry(end+1) = createContext(opts);
opts={hCmap,'Hot',@changeCMap};
hEntry(end+1) = createContext(opts);
opts={hCmap,'Gray',@changeCMap};
hEntry(end+1) = createContext(opts);
opts={hCmap,'Bone',@changeCMap};
hEntry(end+1) = createContext(opts);
opts={hCmap,'Copper',@changeCMap};
hEntry(end+1) = createContext(opts);
opts={hCmap,'Pink',@changeCMap};
hEntry(end+1) = createContext(opts);

opts={hc,'Set Limits',@manual_cmap_limits, 'separator','on'};
createContext(opts);

opts={hc,'Reset Limits',@reset_cmap_limits};
createContext(opts);

% Give each menu item a vector of handles to all peer menus
set(hEntry,'userdata',hEntry);

fixup_context_order(hc);

%-----------------------------------------------------------------
function install_freq_slice_menus(hfig)

% Additional menus to prepend to the spectrogram context menu:

ud = get(hfig,'userdata');
hax_freq = ud.hax(4);
hc = get(hax_freq,'uicontext');  % ud.hax(1) also?

hEntry=[];  % holds handles to each colormap menu item
opts={hc,'Marginal (specgram slice)',@changeFreqSliceMode, 'checked','on'};
hEntry(end+1) = createContext(opts);
%opts={hc,'Integrated (freq PSD)',@changeFreqSliceMode};
opts={hc,'Power Spectral Density',@changeFreqSliceMode};
hEntry(end+1) = createContext(opts);
set(hEntry(end),'enable','on');

% Give each menu item a vector of handles to all peer menus
set(hEntry,'userdata',hEntry);

fixup_context_order(hc);

%-----------------------------------------------------------------
function install_time_slice_menus(hfig)

% Additional menus to prepend to the spectrogram context menu:

ud = get(hfig,'userdata');
hax_tslice   = ud.hax(3);
hc = get(hax_tslice,'uicontext');  % ud.hax(1) also?

hEntry=[];  % holds handles to each colormap menu item
opts={hc,'Marginal (specgram slice)',@changeTimeSliceMode, 'checked','on'};
hEntry(end+1) = createContext(opts);
opts={hc,'Integrated (time zoom)',@changeTimeSliceMode};
hEntry(end+1) = createContext(opts);

% disable last menu until feature implemented:
set(hEntry(end),'enable','off');

% Give each menu item a vector of handles to all peer menus
set(hEntry,'userdata',hEntry);

fixup_context_order(hc);

%-----------------------------------------------------------------
function install_time_panner_menus(hfig)

% Additional menus to prepend to the time-panner context menu:

ud = get(hfig,'userdata');
hthumb = ud.hthumb;  % XXX add to time axis as well?
hc = get(hthumb, 'uicontext');

% Update the menu on-the-fly:
set(hc,'callback', @focus_menu_render_callback);

hEntry=[];  % holds handles to each colormap menu item

opts={hc,'Focus In',@focusTimeIn};
hEntry(end+1) = createContext(opts);

opts={hc,'Previous Focus',@focusTimePrev};
hEntry(end+1) = createContext(opts);

opts={hc,'Reset Focus',@focusTimeReset};
hEntry(end+1) = createContext(opts);

% Give each menu item a vector of handles to all peer menus
set(hEntry,'userdata',hEntry);

fixup_context_order(hc);

update_focus_history_menu(hfig); % pass any focus context menu

%-----------------------------------------------------------------
function hMenu=createContext(opts)
% Helper function to append additional context menus
args = {'parent',opts{1}, 'label',opts{2}, 'callback',opts{3:end}};
hMenu=uimenu(args{:});

%-----------------------------------------------------------------
function fixup_context_order(hContext)
% Put the first context menu entry (the "What's This?" entry)
%  last in the context menu list, and turn on the separator
%  for the "What's This?" entry
childList = get(hContext,'children');
childList = childList([end 1:end-1]);
set(hContext,'children',childList);
set(childList(1),'separator','on');

%---------------------------------------------------------------
function changeCMap(hco,eventStruct)

hco=gcbo; hfig=gcbf;
% Reset checks on all colormap menu items:
set(get(hco,'userdata'),'checked','off');
set(hco,'checked','on');

% Update figure colormap:
cmapStr = lower(get(hco,'label'));
cmap = feval(cmapStr);
set(hfig,'colormap',cmap);

%---------------------------------------------------------------
function changeSpecgramMode(hco,eventStruct)

hco=gcbo; hfig=gcbf;
% Reset checks on all menu items:
set(get(hco,'userdata'),'checked','off');
set(hco,'checked','on');

% Update userdata cache:
% Update display:

%---------------------------------------------------------------
function changeFreqSliceMode(hco,eventStruct)

hco=gcbo; hfig=gcbf;
% Reset checks on all menu items
set(get(hco,'userdata'),'checked','off');
set(hco,'checked','on');

% Update userdata cache:
% Update display:
left_plot_toggle;

%---------------------------------------------------------------
function changeTimeSliceMode(hco,eventStruct)

hco=gcbo; hfig=gcbf;
% Reset checks on all menu items
set(get(hco,'userdata'),'checked','off');
set(hco,'checked','on');

% Update userdata cache:
% Update display:


% ---------------------------------------------------------------
% F O C U S    S Y S T E M
% --------------------------------------------------------------

%---------------------------------------------------------------
function push_curr_to_focus_history(hfig)

ud = get(hfig,'userdata');
hax_time = ud.hax(2);

% focus history is stored in userdata of time-panner axis
% as either an empty vector or cell, or as
% a cell-array of 2-element x-lim vector.

% get current time-axis limits
curr_xlim = get(hax_time,'xlim');

curr_history = get(hax_time,'userdata');
if isempty(curr_history),
	updated_focus_history = {curr_xlim};
else
	updated_focus_history = [curr_history {curr_xlim}];
end
set(hax_time,'userdata',updated_focus_history);

update_focus_history_menu(hfig);

%---------------------------------------------------------------
function hist_xlim = pop_from_focus_history(hfig)

ud = get(hfig,'userdata');
hax_time = ud.hax(2);
curr_xlim = get(hax_time,'xlim'); % get current time-axis limits

curr_history = get(hax_time,'userdata');
if isempty(curr_history),
    % no prev focus info recorded
    warning('Attempt to pop empty focus stack');
    hist_xlim = curr_xlim;
    
    %im_xdata = get(ud.himage,'xdata');
    %hist_xlim = [min(im_xdata) max(im_xdata)];
else
    % Pop last history xlim
    hist_xlim = curr_history{end};
    curr_history(end) = [];
    set(hax_time,'userdata',curr_history);
end

update_focus_history_menu(hfig);

%---------------------------------------------------------------
function clear_focus_history(hfig)
% Remove all previous focus entries

ud = get(hfig,'userdata');
hax_time = ud.hax(2);
set(hax_time,'userdata',[]);

update_focus_history_menu(hfig);

%---------------------------------------------------------------
function update_focus_history_menu(hfig)

ud = get(hfig,'userdata');
hax_time = ud.hax(2);

% Update 'Previous Focus' context menu label:
%
curr_history = get(hax_time,'userdata');
histLen = length(curr_history);
str = 'Previous Focus';
if histLen>0,
	str = [str ' (' num2str(histLen) ')'];
    ena = 'on';
else
    ena = 'off';
end

% Get panner context menu handle:
hmenu = findobj( get(get(ud.hthumb, 'uicontext'),'children'),'label','Focus In');
hAllMenus = get(hmenu,'userdata'); % vector of handles to context menus
hFocusPrev = hAllMenus(2);
set(hFocusPrev, 'label',str);
set(hAllMenus(2:3), 'enable',ena);  % Prev and Reset Focus menus

%---------------------------------------------------------------
function focus_menu_render_callback(hco, eventStruct)
% Used to update the enable of the "Focus In" menu item
% Only enabled if thumb_xlim ~= curr_xlim

hfig=gcbf; hparent=gcbo;
ud = get(hfig,'userdata');
hAllMenus = get(hparent,'children'); % vector of handles to context menus

% Enable 'Focus on Window' if zoom window is less than entire panner
%
hFocusIn = hAllMenus(end);  % 'Focus on Zoom' entry
hax_time = ud.hax(2);
curr_xlim = get(hax_time,'xlim'); % get current time-axis limits
% Get thumbnail xlim vector:
thumb_xdata = get(ud.hthumb,'xdata');  % current thumbnail patch coords
thumb_xlim  = [min(thumb_xdata) max(thumb_xdata)]; % convert to xlim
if ~isequal(curr_xlim, thumb_xlim),
    ena='on';
else
    ena='off';
end
set(hFocusIn,'enable',ena);

%---------------------------------------------------------------
function focusTimeIn(hco,eventStruct)

hfig=gcbf;

% get current time-axis (panner) limits
ud = get(hfig,'userdata');
hax_time = ud.hax(2);
curr_xlim = get(hax_time,'xlim');

% Get thumbnail xlim vector:
thumb_xdata = get(ud.hthumb,'xdata');  % current thumbnail patch coords
thumb_xlim  = [min(thumb_xdata) max(thumb_xdata)]; % convert to xlim

if ~isequal(curr_xlim, thumb_xlim),
    push_curr_to_focus_history(hfig);
    
    % Zoom in to thumb limits
    hax_time = ud.hax(2);

    if 0
        xidx = round(1+thumb_xlim*ud.Fs);
        yfocus = ud.y(xidx(1):xidx(2));
        ylim = [min(yfocus)  max(yfocus)];
        set(hax_time, 'ylim',ylim);
    end
    
    set(hax_time,'xlim', thumb_xlim);
    update_axes_with_eng_units(gcbf);
end

%---------------------------------------------------------------
function focusTimePrev(hco,eventStruct)

hfig=gcbf;
ud = get(hfig,'userdata');
hax_time = ud.hax(2);

% Reset to last focus
xlim = pop_from_focus_history(hfig);

if 0
    xidx = round(1+xlim*ud.Fs);
    yfocus = ud.y(xidx(1):xidx(2));
    ylim = [min(yfocus)  max(yfocus)];
    set(hax_time, 'ylim',ylim);
end

set(hax_time, 'xlim',xlim);
update_axes_with_eng_units(gcbf);

%---------------------------------------------------------------
function focusTimeReset(hco,eventStruct,hfig)
% Remove all previous focus entries

if nargin<3, hfig=gcbf; end
clear_focus_history(hfig);

% Reset focus zoom:
ud = get(hfig,'userdata');
hax_time = ud.hax(2);
im_xdata = get(ud.himage,'xdata');
xlim = [min(im_xdata) max(im_xdata)];

if 0
    xidx = round(1+xlim*ud.Fs);
    yfocus = ud.y(xidx(1):xidx(2));
    ylim = [min(yfocus)  max(yfocus)];
    set(hax_time,'ylim',ylim);
end

set(hax_time,'xlim',xlim);
update_axes_with_eng_units(gcbf);

% ---------------------------------------------------------------
% PARAMETER WINDOW
% --------------------------------------------------------------
% function create_param_gui
% XXX UNUSED


% ---------------------------------------------------------------
% AXES UPDATE FUNCTIONS
% --------------------------------------------------------------
function update_left_plot(hfig)
% UPDATE_LEFT_PLOT Updates the frequency plot with the appropriate analysis

ud = get(hfig,'UserData');
mode = ud.plot.left;
if strcmp(mode,'spectrogram_freq_slice'),
	update_freqslice(hfig);
else
	update_psdplot(hfig);
end

% --------------------------------------------------------------
function update_freqslice(hfig)
% UPDATE_FREQSLICE Update the Frequency Slice (on the left axes)

ud = get(hfig,'UserData');
set(ud.hfreq_line, 'xdata',get_spec_freq(hfig),'ydata',ud.f);
hax_freq = ud.hax(4);

b = get(ud.himage,'cdata');
blim = [min(b(:)) max(b(:))];
spec_ylim = [0 max(ud.f)];
xlabel('dB');
set(hax_freq, ...
	'YLim',spec_ylim, ...
	'XLim',blim,...
	'XtickMode','auto');
set(hax_freq, 'Xtick', return2ticks(hax_freq));

% Update extent of horizontal crosshair:
set(ud.hfreq_x, 'xdata',blim);


% --------------------------------------------------------------
function update_psdplot(hfig)
% UPDATE_PSDPLOT Update the PSD plot (on the left axes)

ud = get(hfig,'UserData');
wstate = warning;
warning off;
density = 10*log10(ud.Pxx);
warning(wstate);

hax_freq = ud.hax(4);

% Update the PSD plot with data and limits
set(ud.hfreq_line,'Xdata',density,'Ydata',ud.w);
xlim = [min(density(:)) max(density(:))];
xlabel('dB/Hz');
set(hax_freq, ...
	'YLim',     [0 ud.Fs/2],'XLim',xlim,...
	'XTickMode','auto');
set(hax_freq, 'Xtick', return2ticks(hax_freq));

% Update extent of horizontal crosshair:
set(ud.hfreq_x, 'xdata',xlim);


% ---------------------------------------------------------------
% UTILITY FUNCTIONS
% --------------------------------------------------------------
function new_xtick = return2ticks(haxes)
% RETURN2TICKS Utility to return two tick marks
x = get(haxes,'Xtick');
if length(x)>2,
	new_xtick = [x(1) x(end)];
else
	new_xtick = x;
end

%--------------------------------------------------------------
% [EOF] specgramdemo.m