pixval.m

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      end
   end
end
set(displayBar, 'UserData', dbud);

%%%
%%%  Sub-function - OverImage
%%%

function [imageHandle,imageType,img,x,y] = OverImage(figHandle)
% Return the index of which image we are over, and return a 0 if we
% aren't above an image.

images = findobj(figHandle, 'type', 'image');
if isempty(images)
   imageHandle=0; imageType=''; img=[]; x=0; y=0;
   return
end
% Make sure that the Image's Button Down & Up functions will queue
set(images, 'ButtonDownFcn', 'pixval(''ButtonDownOnImage'')', ...
   'Interruptible', 'off', 'BusyAction', 'Queue');
axHandles = get(images, {'Parent'});
oldAxesUnits = get([axHandles{:}], {'Units'});
set([axHandles{:}], 'Units', 'pixels');
axPositions = get([axHandles{:}], {'Position'});
axCurPt = get([axHandles{:}], {'CurrentPoint'});
set([axHandles{:}], {'Units'}, oldAxesUnits);

% Loop over the axes, see if we are above any of them
imageHandle = 0;  
for k=1:length(axHandles)
   XLim = get(axHandles{k}, 'XLim');
   YLim = get(axHandles{k}, 'YLim');
   pt = axCurPt{k};
   x = pt(1,1); y = pt(1,2);
   if x>=XLim(1) & x<=XLim(2) & y>=YLim(1) & y<=YLim(2)
      imageHandle = images(k);
      break;
   end
end

% Figure out image type
if imageHandle ~= 0
   [img,flag] = getimage(imageHandle);
   [rows,cols,colors] = size(img);
   x_pix = axes2pix(cols, get(imageHandle,'XData'),pt(1,1));
   y_pix = axes2pix(rows, get(imageHandle,'YData'),pt(1,2));
   x = min(cols, max(1, round(x_pix))); 
   y = min(rows, max(1, round(y_pix)));
   if x_pix<0.5 | y_pix<0.5 | x_pix>cols+.5 | y_pix>rows+.5
      % We're above the axes but not the image
      imageHandle=0; imageType=''; img=[]; x=0; y=0;
      return
   end
      
   switch flag
   case 1
      imageType = 'indexed';
   case {2,3}  % Grayscale or binary
      imageType = 'intensity';
   case 4
      imageType = 'rgb';
   otherwise
      error(['Invalid image, GETIMAGE returned flag = ' flag '.']);
   end
else
   imageHandle=0; imageType=''; img=[]; x=0; y=0;
end



   
%%%
%%%  Sub-function - UpdatePixelValues
%%%

function UpdatePixelValues(imageHandle, imageType, displayBar,img,x,y)
%   This is the motion callback for when we are displaying
%   pixels.  Either we are in automatic display mode and the
%   mouse pointer is moving around or we are in normal mode
%   and there has been a button-down but not yet a button up.
%   I get the current point and update the string.

dbud = get(displayBar, 'UserData');
if strcmp(imageType,'indexed')
   map=get(dbud.figureHandle, 'Colormap');
   idx = img(y,x);
   if isa(idx, 'uint8'),
      idx = double(idx)+1;
   end
   idx = round(idx);
   if idx<=size(map,1)
      pixel = map(idx,:);
   else
      pixel = map(end,:);
   end
else   
   pixel = double(img(y,x,:));
end

% figure out the new string
switch dbud.displayMode
case 'normal'   % Just display intensity information
   if strcmp(imageType,'rgb') | strcmp(imageType,'indexed')
      if isa(img, 'uint8') &  strcmp(imageType,'rgb')
         pixval_str = sprintf(' %3d, %3d = %3d,%3d,%3d', ...
            x,y,pixel(1),pixel(2),pixel(3));
      else  % all indexed images use double precision colormaps
         pixval_str = sprintf(' %3d, %3d = %6.4f,%6.4f,%6.4f', ...
            x,y,pixel(1),pixel(2),pixel(3));
      end
   else % intensity
      if isa(img, 'uint8')
         pixval_str = sprintf(' %3d, %3d = %3d',x,y,pixel(1));
      else
         pixval_str = sprintf(' %3d, %3d = %6.4f',x,y,pixel(1));
      end
   end
   
case 'distance'
   delta_x = (x - dbud.x0);
   delta_y = (y - dbud.y0);
   dist = sqrt(delta_x^2 + delta_y^2);
   set(dbud.line, 'XData', [dbud.x0 x], 'YData', [dbud.y0 y]);
   
   if strcmp(imageType,'rgb') | strcmp(imageType,'indexed')
      if isa(img, 'uint8') &  strcmp(imageType,'rgb')
         pixval_str = sprintf(' %3d, %3d = %3d,%3d,%3d  dist = %3.3f', ...
            x,y,pixel(1),pixel(2),pixel(3),dist);
      else  % all indexed images use double precision colormaps
         pixval_str = sprintf(' %3d, %3d = %6.4f,%6.4f,%6.4f  dist = %3.3f', ...
            x,y,pixel(1),pixel(2),pixel(3),dist);
      end
   else % intensity
      if isa(img, 'uint8')
         pixval_str = sprintf(' %3d, %3d = %3d  dist = %3.3f', ...
            x,y,pixel(1),dist);
      else
         pixval_str = sprintf(' %3d, %3d = %6.4f  dist = %3.3f', ...
            x,y,pixel(1),dist);
      end
   end
end
set(displayBar, 'String', pixval_str, 'UserData', dbud);



%%%
%%%  Sub-function - ButtonDownOnImage
%%%

function ButtonDownOnImage

imageHandle = gcbo;
figureHandle = get(get(imageHandle,'Parent'),'Parent');
displayBar = findobj(figureHandle, 'Tag', 'pixel value display bar');
dbud = get(displayBar, 'UserData');
axesHandle = get(imageHandle, 'Parent');
% Set the initial point (x0,y0)
pt = get(axesHandle, 'CurrentPoint');
[rows,cols,colors] = size(get(imageHandle, 'Cdata'));
x_pix = axes2pix(cols, get(imageHandle,'XData'),pt(1,1) );
y_pix = axes2pix(rows, get(imageHandle,'YData'),pt(1,2) );
dbud.x0 = min(cols, max(1, round(x_pix))); 
dbud.y0 = min(rows, max(1, round(y_pix)));
dbud.line = line('Parent', axesHandle, ...
   'erasemode', 'xor', ...
   'color', [1 0 0], ...
   'Xdata', [dbud.x0 dbud.x0], ...
   'Ydata', [dbud.y0 dbud.y0]);
dbud.displayMode = 'distance';
dbud.buttonDownImage = imageHandle;
set(displayBar, 'UserData', dbud);
set(dbud.figureHandle, 'WindowButtonUpFcn', 'pixval(''BackToNormalPixvalDisplay'')');
PixvalMotionFcn(displayBar);


%%%
%%%  Sub-function - BackToNormalPixvalDisplay
%%%

function BackToNormalPixvalDisplay

displayBar = findobj(gcbo, 'Tag', 'pixel value display bar');
dbud = get(displayBar, 'UserData');
imageHandle = dbud.buttonDownImage;
delete(dbud.line);
dbud.line = [];
dbud.x0 = []; dbud.y0 = [];
set(dbud.figureHandle, 'WindowButtonUpFcn', '');
dbud.displayMode = 'normal';
dbud.buttonDownImage = 0;
set(displayBar, 'UserData', dbud);
PixvalMotionFcn(displayBar);



%%% 
%%%  Sub-function - MoveDisplayBar
%%%

function MoveDisplayBar

displayBar = gcbo;
dbud = get(displayBar, 'UserData');
oldWindowMotionFcn = get(dbud.figureHandle, 'WindowButtonMotionFcn');
set(dbud.figureHandle, 'WindowButtonMotionFcn', '');
oldPointer = get(dbud.figureHandle, 'Pointer');
oldPointerShapeCData = get(dbud.figureHandle, 'PointerShapeCData');
oldPointerShapeHotSpot = get(dbud.figureHandle, 'PointerShapeHotSpot');
setptr(dbud.figureHandle,'closedhand'); 

txtpos = get(displayBar, 'Position');
frmPos = get(dbud.DisplayFrame, 'Position');
position = txtpos + [0 0 frmPos(3) 0];
position2 = dragrect(position);
dx = position2(1)-position(1);
dy = position2(2)-position(2);

txtpos = txtpos + [dx dy 0 0];
set(displayBar, 'Position', txtpos);

frmPos = frmPos + [dx dy 0 0];
set(dbud.DisplayFrame, 'Position', frmPos);

btnPos = get(dbud.CloseButton, 'Position');
btnPos = btnPos + [dx dy 0 0];
set(dbud.CloseButton, 'Position', btnPos);

set(dbud.figureHandle, 'Pointer', oldPointer, ...
   'PointerShapeCData', oldPointerShapeCData, ...
   'PointerShapeHotSpot', oldPointerShapeHotSpot)
set(dbud.figureHandle, 'WindowButtonMotionFcn', oldWindowMotionFcn);




%%%
%%%  Sub-function - DeleteDisplayBar
%%%

function DeleteDisplayBar(displayBar)
%  Take apart the pixel value display - get rid of the text
%  uicontrol and clean up the image objects (remove their 
%  UserData's and get rid of their ButtonDown & Delete Fcn's)

if nargin<1
   displayBar = findobj(gcbf, 'Tag', 'pixel value display bar');
end

if ~isempty(displayBar) % if it's empty, there's no work to do.
   dbud = get(displayBar, 'UserData');
   set(displayBar, 'DeleteFcn', '');  % Make sure there's no recursion
   if ishandle(displayBar)
      delete(displayBar); 
   end
   if ishandle(dbud.CloseButton)
      delete(dbud.CloseButton);
   end
   if ishandle(dbud.DisplayFrame)
      delete(dbud.DisplayFrame);
   end
   % We no longer restore the interactive state of the figure.
   % uirestore(dbud.oldFigureUIState);
   uisuspend(dbud.figureHandle);
end



%%% 
%%%  Sub-function - CreatePointer
%%% 

function [pointerShape, pointerHotSpot] = CreatePointer

pointerHotSpot = [8 8];
pointerShape = [ ...
      NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   1   1   1   1   1   1   2 NaN   2   1   1   1   1   1   1   1
   2   2   2   2   2   2   2 NaN   2   2   2   2   2   2   2   2
   NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
   2   2   2   2   2   2   2 NaN   2   2   2   2   2   2   2   2
   1   1   1   1   1   1   2 NaN   2   1   1   1   1   1   1   1
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN   1   2 NaN   2   1 NaN NaN NaN NaN NaN NaN
   NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN];