Bad clarity using export_fig - matlab

I am using Export_fig to export figs from matlab, I am getting very good plots generally. But when i add some textboxs and arrows in the fig. the clarity is pathetic.
I use the -transparent property, which does not work either.
export_fig('path', '-pdf','-transparent')
Anyone knows what is happening here. Normally this works very good, only when the text is added it acts like this way. Not sure if it's a glitch in the code or if i am doing anything wrong.
Note: I added the text and arrows with insert option on the menu bar.

If you are not set on using Export_fig for other reasons, consider using MATLAB's built-in print function and increase the resolution with the -r attribute
print('path', '-dpdf', '-r300')
where 'path' is the desired 'path\filename.pdf', '-dpdf' sets the file type, and '-r300' sets the resolution to 300 dpi, also try '-r0' for screen resolution, or higher, till you get what you want.
I'm not sure what the '-transparent' argument is used for but there is probably an equivalent you can find in the documentation.
https://www.mathworks.com/help/matlab/ref/print.html

Related

Matlab: Export a figure made with myaa

I am trying to get better quality phase plots of complex functions made with the Complex Function Explorer of E. Wegert CFE. For this purpose I apply the Matlab anti-aliasing function myaa.m to the phase plots that are made with the CFEGUI.m. For the example screenshot of the result window below I used the setting myaa([8 8]) in the Matlab command window which means that the supersampling enlarge the figure 8x and then downscale it to 1/8 to get the original h x w.
As one can see the window of the figure has no operation icons or menu options for save or print. My question is what to do with such a figure (beside making screenshots)? Can I somehow use export-fig to save such a figure or load it in an image array and if yes, how?
It is also possible to use the setting myaa([8 1]) which results in a very large figure window that is larger than my screen (and has the unpleasant attribute that it can not be moved). It would be even better if such a whole figure could be saved (not only the visible part).
You can use getframe to grab current figure information in pixels.
However, while I do not know how this affects you, notice that MATLAB versions above 2014b (included) have already anti-aliasing. The code you linked seem to be from 2008, I am not 100% sure if it has become obsolete now.

How to stop MATLAB clipping the title of a figure when I print

When I create a figure with MATLAB with a title, then use the File|Print option to print the figure, the title is clipped. Please try this code for an example
t = linspace(0,2*pi,1000);
s = sin(t);
figure
plot(t,s)
titleString = sprintf('Multi\nLine\nTitle');
title(titleString)
disp('Now press File|Print Preview on the figure and observe that the title is clipped.')
disp('This happens with all titles, the multi line title makes it more obvious.')
disp('I know I can fix it with Fill Page or Center, but I should not have too.')
You can also see the problem in print preview. As I say in the example code, I know I can get round the problem using Print Preview then Fill Page or Center, but I don't want people using my code to have to use a work around.
I have observed this problem with r2014a and r2015b. I assume other releasse are also affected.
Is there setting I can make before creating the figure that centres the plot or fills the page and makes the problem go away? Is there some other setting I should make to avoid the problem?
Here is a little more debug information. If I press File|Print Preview, MATLAB reports Left 0.64, Top -0.59, Width 20.32, Height 15.24. I guess the problem is related to the negative Top value. These are defaults from MATLAB; I have not made any attempt to change these values.
One extra thing. I am in the UK, so my default paper/printer setting will be for A4 paper, if that makes a difference.
Edit:
It looks like my problems are caused by two lines further up in my program:
set(0,'DefaultFigurePaperOrientation','landscape')
set(0,'DefaultFigurePaperType','A4')
I think that becuase plots expect to be on paper with a portrait orientation, I am seeing these problems.
Perhaps I should revise my question to: what to I need to change in MATLAB figures so they print correctly on landscape A4 paper (ideally in the center, scaled to fill the page, but with correct orientation). All this without using Print Preview.
But I am going to do this instead to code around my problem.
set(0,'DefaultFigurePaperOrientation','portrait')
set(0,'DefaultFigurePaperType','A4')
I can't seem to reproduce your problem on the computer I'm currently on (see the values I'm getting by default - Top is 8.11):
However, if your problem is what I think it is (I'm getting something that fits this description on another computer I'm working on), try adding _{ } at the end of your string. This is a TeX string meaning "subscripted space" which pushes the rest of the text slightly upward. You can also use ^{ } on the first line if the clipping is happening from the top. I found this workaround to work on axis titles and labels as well.
Exaggerated, the workaround looks like this:
titleString = sprintf('^{^{^{^{^{^{ }}}}}}Multi\nLine\nTitle');
Which shows the word "Multi" even for Top = -0.59.
If the above is not what you're looking for, you might want to look at the robust export_fig.
I can confirm that my clipping problems are caused by this line:
set(0,'DefaultFigurePaperOrientation','landscape')
I have revised my program to start with this instead.
set(0,'DefaultFigurePaperOrientation','portrait')
set(0,'DefaultFigurePaperType','A4')
And the problem has gone away.
Users can still print in landscape if they use the print preview feature.

Exporting figures as vector graphics in .pdf-format using HG2-Update and 'painters' renderer is not working properly

I'm using the still undocumented HG2-Update to create my MATLAB plots, because they just look that much nicer.
(Source: Yair Altman)
Actually, using the current version Release 2013b it works quite nicely and there are not much issues. Except one wants to export the figures as vector graphics (renderer: '-painters'), especially as pdf.
I use the commands:
saveas(gcf,'test.pdf','pdf')
or
print(gcf,'test.pdf','-dpdf')
There are rendering issues, the print does not contain the whole figure and some parts are cropped or non-default fonts are not recognized.
But I'd really like to stay with HG2 and I'd still like to use vector graphics. Is there any solution or workaround?
Exporting vector graphics using the yet not official HG2-Update is quite an issue. The .pdf-export is still totally screwed up.
What is working fine is the .svg-export, apart from that the boundary box is not set properly.
The long workaround would be:
Save the plot with '-dsvg' (print-command) or 'svg' (saveas-command) as vector graphic, open the file in the open source application Inkscape and save again as .pdf with the Export area is drawing checkmark set.
Quite complicated, so I found a way to do it via command-line directly from Matlab (Inkscape still required!):
filename = 'test';
inkscapepath = '"C:\Program Files (x86)\Inkscape\inkscape.exe"';
%// save as .svg
saveas(gcf,filename,'svg')
%// open and save with "export-area-drawing" set via command line
system( [inkscapepath ' ' filename ...
'.svg --export-area-drawing --export-pdf=' filename '.pdf'])
It takes some time, but works without any known issues for now.
Additionally delete the svg-File afterwards:
delete([filename '.svg'])
I had the same problem and used the workaround from thewaywewalk. Now I discovered the MATLAB function "hgexport" works under HG2 (in R2014a).
An issue still was the paper size. I want to use the same size for all graphs with as little white frame as possible. Here you have to set two sizes:
The papersize is set with set(gcf,'PaperSize',[width height]) and the size of your chart is set through export styles. These are set in "Export Setup" or command line:
exp_style=hgexport('readstyle','default');
exp_style.Width = 'width';
exp_style.Height = 'height';
exp_style.Renderer = 'painters';
Now you can export your pdf:
hgexport(gcf,'pdfname',exp_style,'Format','pdf');
PS: In HG2 you may also use Latex for tick labels:
set(gca,'TickLabelInterpreter','latex');

Matlab imwrite() quality

I'm very new to Matlab, though I know a few other programming languages, so please forgive me if this is something simple. I have not been able to find any answers to this, either on StackOverflow or elsewhere.
I produce a figure using the following code:
figure(6),imageplot(P); drawnow;
Which looks like this:
I then save this image to my computer using the following commands:
imwrite(P, 'images/plot.png');
And the resulting image is tiny, and missing some of the color information:
If, however, I utilize the save function in the open figure (image #1) and save it manually, I get exactly what I want, which is that exact image stored on my computer.
How would I program that? I assumed that imwrite() would just write the image directly, but apparently I'm doing something wrong. Any advice? Perhaps it has something to do with the imageplot command? I cannot seem to get that to work in imwrite.
Update: Based on the comments below, I have begun using "imresize" with the "nearest" option. This scales the image properly, but the resulting image is still curiously darker (and therefore has less information) than if I hit the "save" button in the figure.
Image saved from figure:
Image using "imresize" with "nearest" option:
The MATLAB imwrite command saves exactly the number of pixels as specified in your image matrix. This is the actual result of your computation; the reason the output is "tiny" is because it is supposed to be. To make it larger, would be to simply scale/zoom it as required.
The save figure option however does something quite different: it rasterizes the the output you obtain in the figure window and gives you the option for saving it as an image. This is evident in the fact that when you do so, you obtain a white background in addition to your result which is really just the grey background you see before you save it; this can be adjusted by resizing the figure window before utilizing the save option.
If you're looking to simply make the output figure larger, I would recommend using something along the lines of the imresize command.
Say, if you want the default size to be twice the size of the real result, simply use:
imresize(P, 2.0);
For more options, try help imresize.
The command you need for the "Save As..." functionality of figures is called "print". I often use
print(gcf, '-dpng', 'some_filename.png')
or
print(gcf, '-depsc', 'some_filename.eps','-r0')
to save a figure as it is shown on screen. The format png offers a small filesize and excellent quality, and it is understood by most image viewers and browsers. The eps format is a vector format, which I use for printig. The '-r0' option specifies "use the same size as given by the screen resolution" for the vector format properties.

How to print figure to clipboard by PRINT function with the quality identical to 'Edit-->Copy Figure' option?

Is there any way to print the figure to the clipboard so that the quality is identical to what the Edit-->Copy Figure option provides?
I used to save the figure to powerpoint file by using saveppt.m obtained from Matlab Central. It worked well until yesterday. I noticed that the stored image quality was somehow degraded. I tried to re-generate some ppt slides with exactly the same script and the same source data, but the new slides are simply of worse quality.
I investigated into this problem a little bit and discovered that when the figure is copied to clipboard by running print -dmeta, the image in the clipboard is already degraded, while if I use the Edit-->Copy Figure option in the figure window, I get the image as clear as the original image in the figure window.
Following is an example for your reference. I copied the image from a figure to the clipboard by two different methods, and paste it to Microsoft Paint program, and cut a piece of it to show below:
The image using print -dmeta:
The image using Edit-->Copy Figure:
If you compare the Xtick label '50', you may see that the image from Edit-->Copy Figure is smoother.
At the beginning I thought it was a problem of the resolution, but setting -rN to change the resolution does not seem to resolve my problem, at least not for N<=300.
Thank you for your help.
The short answer... Use the same function invoked in the callback for that menu item:
editmenufcn(gcf,'EditCopyFigure');
The longer answer... How exactly did I find this? You can look at my previous answer to a related question about reproducing what is done by a File menu option. The concept is the same, just for a different figure menu. For example, this will find the callback you want for the currently active figure window:
>> hCopyFigure = findall(gcf,'Label','Copy &Figure'); %# Handle for the "Copy
%# Figure" menu item
>> get(hCopyFigure,'Callback') %# Callback invoked when that item is selected
ans =
editmenufcn(gcbf,'EditCopyFigure')
The function EDITMENUFCN is another one of those sparsely documented functions, but looking through the code (by typing edit editmenufcn.m) shows that it either invokes Java (if you're on a Mac) or the undocumented function UIMENUFCN.
I think I found the answer myself. Using print -dmeta -painters to specify the renderer resolves my problem.
In File-->Preference-->Figure Copy Template-->Copy Option I noticed there are 3 options:
Metafile
Preserve information
Bitmap
I found that if I select 1, the Edit-->Copy Figure outputs the same image as print -dmeta. So I kind of confirmed the information I need is in the Preserve information option. A quick google search led me to the discussion about the potential difference of the applied renderer, and eventually I confirmed that using painters will print the image to the clipboard in the way I wanted.
The image in the question seems to be generated by the renderer zbuffer and painters, respectively. I still don't know why the default renderer of paint -dmeta changes, though.