%PRINT2ARRAY Exports a figure to an image array
%
% Examples:
% A = print2array
% A = print2array(figure_handle)
% A = print2array(figure_handle, resolution)
% A = print2array(figure_handle, resolution, renderer)
% [A bcol] = print2array(...)
%
% This function outputs a bitmap image of the given figure, at the desired
% resolution.
%
% If renderer is '-painters' then ghostcript needs to be installed. This
% can be downloaded from: http://www.ghostscript.com
%
% IN:
% figure_handle - The handle of the figure to be exported. Default: gcf.
% resolution - Resolution of the output, as a factor of screen
% resolution. Default: 1.
% renderer - string containing the renderer paramater to be passed to
% print. Default: '-opengl'.
%
% OUT:
% A - MxNx3 uint8 image of the figure.
% bcol - 1x3 uint8 vector of the background color
% Copyright (C) Oliver Woodford 2008-2012
% 05/09/11: Set EraseModes to normal when using opengl or zbuffer
% renderers. Thanks to Pawel Kocieniewski for reporting the
% issue.
% 21/09/11: Bug fix: unit8 -> uint8! Thanks to Tobias Lamour for reporting
% the issue.
% 14/11/11: Bug fix: stop using hardcopy(), as it interfered with figure
% size and erasemode settings. Makes it a bit slower, but more
% reliable. Thanks to Phil Trinh and Meelis Lootus for reporting
% the issues.
% 09/12/11: Pass font path to ghostscript.
% 27/01/12: Bug fix affecting painters rendering tall figures. Thanks to
% Ken Campbell for reporting it.
% 03/04/12: Bug fix to median input. Thanks to Andy Matthews for reporting
% it.
% 26/10/12: Set PaperOrientation to portrait. Thanks to Michael Watts for
% reporting the issue.
function [A, bcol] = print2array(fig, res, renderer)
% Generate default input arguments, if needed
if nargin < 2
res = 1;
if nargin < 1
fig = gcf;
end
end
% Warn if output is large
old_mode = get(fig, 'Units');
set(fig, 'Units', 'pixels');
px = get(fig, 'Position');
set(fig, 'Units', old_mode);
npx = prod(px(3:4)*res)/1e6;
if npx > 30
% 30M pixels or larger!
warning('MATLAB:LargeImage', 'print2array generating a %.1fM pixel image. This could be slow and might also cause memory problems.', npx);
end
% Retrieve the background colour
bcol = get(fig, 'Color');
% Set the resolution parameter
res_str = ['-r' num2str(ceil(get(0, 'ScreenPixelsPerInch')*res))];
% Generate temporary file name
tmp_nam = [tempname '.tif'];
if nargin > 2 && strcmp(renderer, '-painters')
% Print to eps file
tmp_eps = [tempname '.eps'];
print2eps(tmp_eps, fig, 0, renderer, '-loose');
try
% Initialize the command to export to tiff using ghostscript
cmd_str = ['-dEPSCrop -q -dNOPAUSE -dBATCH ' res_str ' -sDEVICE=tiff24nc'];
% Set the font path
fp = font_path();
if ~isempty(fp)
cmd_str = [cmd_str ' -sFONTPATH="' fp '"'];
end
% Add the filenames
cmd_str = [cmd_str ' -sOutputFile="' tmp_nam '" "' tmp_eps '"'];
% Execute the ghostscript command
ghostscript(cmd_str);
catch me
% Delete the intermediate file
delete(tmp_eps);
rethrow(me);
end
% Delete the intermediate file
delete(tmp_eps);
% Read in the generated bitmap
A = imread(tmp_nam);
% Delete the temporary bitmap file
delete(tmp_nam);
% Set border pixels to the correct colour
if isequal(bcol, 'none')
bcol = [];
elseif isequal(bcol, [1 1 1])
bcol = uint8([255 255 255]);
else
for l = 1:size(A, 2)
if ~all(reshape(A(:,l,:) == 255, [], 1))
break;
end
end
for r = size(A, 2):-1:l
if ~all(reshape(A(:,r,:) == 255, [], 1))
break;
end
end
for t = 1:size(A, 1)
if ~all(reshape(A(t,:,:) == 255, [], 1))
break;
end
end
for b = size(A, 1):-1:t
if ~all(reshape(A(b,:,:) == 255, [], 1))
break;
end
end
bcol = uint8(median(single([reshape(A(:,[l r],:), [], size(A, 3)); reshape(A([t b],:,:), [], size(A, 3))]), 1));
for c = 1:size(A, 3)
A(:,[1:l-1, r+1:end],c) = bcol(c);
A([1:t-1, b+1:end],:,c) = bcol(c);
end
end
else
if nargin < 3
renderer = '-opengl';
end
err = false;
% Set paper size
old_pos_mode = get(fig, 'PaperPositionMode');
old_orientation = get(fig, 'PaperOrientation');
set(fig, 'PaperPositionMode', 'auto', 'PaperOrientation', 'portrait');
try
% Print to tiff file
print(fig, renderer, res_str, '-dtiff', tmp_nam);
% Read in the printed file
A = imread(tmp_nam);
% Delete the temporary file
delete(tmp_nam);
catch ex
err = true;
end
% Reset paper size
set(fig, 'PaperPositionMode', old_pos_mode, 'PaperOrientation', old_orientation);
% Throw any error that occurred
if err
rethrow(ex);
end
% Set the background color
if isequal(bcol, 'none')
bcol = [];
else
bcol = bcol * 255;
if isequal(bcol, round(bcol))
bcol = uint8(bcol);
else
bcol = squeeze(A(1,1,:));
end
end
end
% Check the output size is correct
if isequal(res, round(res))
px = [px([4 3])*res 3];
if ~isequal(size(A), px)
% Correct the output size
A = A(1:min(end,px(1)),1:min(end,px(2)),:);
end
end
end
% Function to return (and create, where necessary) the font path
function fp = font_path()
fp = user_string('gs_font_path');
if ~isempty(fp)
return
end
% Create the path
% Start with the default path
fp = getenv('GS_FONTPATH');
% Add on the typical directories for a given OS
if ispc
if ~isempty(fp)
fp = [fp ';'];
end
fp = [fp getenv('WINDIR') filesep 'Fonts'];
else
if ~isempty(fp)
fp = [fp ':'];
end
fp = [fp '/usr/share/fonts:/usr/local/share/fonts:/usr/share/fonts/X11:/usr/local/share/fonts/X11:/usr/share/fonts/truetype:/usr/local/share/fonts/truetype'];
end
user_string('gs_font_path', fp);
end