libpng警告：使用libpng-1.2.26构建但使用1.5.2运行的应用程序

Question

I have a problem on my mac when trying in R to produce png images.

I am getting this warnings:

libpng warning: Application built with libpng-1.2.26 but running with 1.5.2

I am running the R 2.14 version using the R-studio GUI.

I am not excatly sure about the libpng problem. When I am doing locate libpng-config I'm getting several hits, some with libong-config12, some with libpng-config14, some without nay numbers:

ayeroslaviz:~ ayeroslaviz$ locate libpng-config
/Applications/XAMPP/xamppfiles/bin/libpng-config
/Library/Frameworks/GTK+.framework/Versions/2.18.X11/Resources/bin/libpng-config
/opt/local/bin/libpng-config
/usr/X11/bin/libpng-config
/usr/local/bin/libpng-config

When doing which libpng-config I'm getting: /usr/local/bin/libpng-config

Is there a way to uninstall older versions of libpng or update the paths to the right version. Unfortunately I am not even sure, what thesource of this warning, so I hope I gave here all the needed information.

I would be grateful for anyone who gives me a hint about how to solve this problem.

thanks

A.

Answer 1

Fortunately, you're using a Mac, so there's a simpler (but not documented) method.

quartz.save('my_filename.png', type='png') 

Note that the image you want to save must be the currently active quartz window.

Answer 2

If your code still works, then don't worry about it. The fact this this is a warning rather than an error message means that there might be a problem, not that there definitely is a problem. IF you don't want to see the warning, wrap your R code in a call to suppressMessages .

suppressMessages(code_to_call_libpng)

Answer 3

This problem could occur because RStudio (or some other library you are using in your project) is using in-built libpng libraries (v1.2) and when the application run, the version installed in the system is v1.5: http://www.libpng.org/pub/png/pngfaq.html#mismatch . If this is the point, you could try to upgrade RStudio libpng libraries or downgrade system libpng ones.