Jiro's pick this week is MYAA by Anders Brun.
A few months ago, I wrote a post for Loren's Art of MATLAB blog about creating publication-quality graphics. That post was about controlling various properties of graphics objects to make the visualization a higher quality.
Another way of making better-looking graphics is to use anti-aliasing. Anti-aliasing provides a smoother look to the lines drawn on the screen. PCs use anti-aliasing to make the fonts smoother. With MYAA, you can easily anti-alias your MATLAB graphics. This is great for both on-screen presentation as well as MATLAB publishing (this blog post is a published document).
Original Plot
With the regular screen resolution, you can see the aliasing. It is most apparent with diagonal lines.
membrane
Anti-Aliased Plot
Anti-aliased plot looks much smoother. MYAA supersamples the plot (as an image) and then resizes it (via a filtering method), giving an anti-aliased look.
myaa
If we take a closer look at the two images, you can see the anti-aliasing effect.
im1 = imread('antialias_01.png'); im2 = imread('antialias_02.png'); subplot(1,2,1); imshow(im1(100:150, 300:350, :)); title('Original'); subplot(1,2,2); imshow(im2(100:150, 300:350, :)); title('Anti-Aliased');
More Features
MYAA has additional features that make it a very handy tool. For example, you can specify the supersampling factor to provide an even smoother look. The tool also has a nice interactive feature where you can refresh the graphics (after zooming or rotating the original plot) or zoom in and out with the anti-aliased plot.
Finally, I like how Anders has been quickly updating his entry in response to the user feedback. He posted this file early this month, and he has already updated several times, making this tool more user-friendly.
Comments
Do you ever make presentations directly from MATLAB? What are some tricks you employ to make MATLAB a presentation tool? As a starter, I once created a MATLAB animation player for displaying animations. Tell us about your stories here.
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the MATLAB code
Published with MATLAB® 7.6
Not to be a troll, but I kind of like the way the original plot looks better. Nethertheless, a very cool tool!
In terms of creating presentations, I’ve written some scripts that create plots and then automatically copies and pastes them into a powerpoint presentation. It is really useful when you’re processing a large batch of data!
Hi.
This post raises a question with me: Does matlab use hardware accellerated graphics? And if so, why not allow hardware-accelerated anti-aliasing?
@Daniel,
We do use the hardware, but we don’t expose the supersampling feature through that path, so if you want supersampling, for now you’ll need to do it in software.
@Quan,
Thanks for your comments. Yes, functions for automatically pasting MATLAB plots into a PowerPoint presentation can be very useful. In fact, now you can do this by using MATLAB’s publish capability and selecting PPT as the output format.
http://www.mathworks.com/access/helpdesk/help/techdoc/matlab_env/briymz8-1.html#bri9_s4
Hi,
I just found a tip for anti-ailiasing lines. Just add the attribute ‘LineSmoothing’,'on’. i.e.
line([x0n x1n],[y0n y1n],’LineWidth’,2,’LineSmoothing’,'on’);
It doesn’t appear to be documented in matlab but it works nicely.
Sorry to revive an old post, but another post made me think to look and see if this had been treated before.
My number-1 beef with Matlab is the quality of the display graphics. I don’t understand why
>> plot(1:10,’linewi’,1)
>> hold on
>> plot((1:10)+1,’linewi’,0.5)
look exactly the same on the screen despite looking quite different in anything sent to print. Is there a reason for this limitation in this day and age, or do I have something set inappropriately?
Thanks for your comment, Jody.
You probably don’t see any difference between the lines on the screen, because MATLAB graphics currently don’t support real antialiasing.
For example, a typical screen resolution is 96 pixels per inch. A point is 1/72th of an inch. This means that the 1 point line is 1 1/3 pixels, while the 0.5 point line is 2/3 pixels. So both lines get rounded to 1 pixel.
However, I have relayed your comment over to development.