Why am I unable to specify some display bit-depths less than 24-bit TrueColor for MATLAB 6.5 (R13) on my Solaris computer?

I am using MATLAB 6.5 (R13) from a VNC server on Solaris 8. I am running over a low-bandwidth connection; therefore, I would like to use MATLAB with a low color depth such as 12-bit or 16-bit. When I try to specify these low bit depths, the MATLAB desktop does not initialize properly. With some specified bit depths, MATLAB will create a segmentation violation. Sometimes I get a Java error such as the following:

 An unexpected exception has been detected in native code outside the VM.

 Unexpected Signal : 11 occurred at PC=0xec8d0228

 Function name=Java_sun_awt_image_GifImageDecoder_parseImage

 Library=/vstools/matlab/6.5/sys/java/jre/sol2/jre1.3.1/lib/sparc/motif12/libmawt.so

 Current Java thread:

 at sun.awt.X11GraphicsConfig.makeColorModel(Native Method)

 at sun.awt.X11GraphicsConfig.getColorModel(X11GraphicsConfig.java:145)

 - locked <f04dfa40> (a sun.awt.X11GraphicsConfig)

 at sun.awt.motif.MComponentPeer.getColorModel(MComponentPeer.java:252)

 at sun.awt.motif.X11Graphics.getDeviceColorModel(X11Graphics.java:147)

 at sun.awt.motif.X11Graphics.lock(X11Graphics.java:850)

 .

 .

 .

I was able to specify color depths as low as 12-bit in MATLAB 6.0 (R12) on this system.

Answer 1

[MathWorks Support Team]

The Java Virtual Machine (JVM) that ships with MATLAB 6.5 (R13) for the Solaris platform only supports 24-bit TrueColor displays and above. Therefore, the problem is a limitation with the JVM that MATLAB uses.

There are a couple of methods available to work around this problem:

1) Try using a different version of the JVM for the Solaris system, such as 1.1.8. However, note that MATLAB is only supported for the version of the JVM that MATLAB defaults to. The version of the JVM that MATLAB 6.5 (R13) defaults to is 1.3.1. For instructions on how to change the JVM, see the Related Solution at the bottom of the page.

Some customers have found that older versions of the JRE work better, such as 1.1.8, but newer versions do not.

2) Try using an 8-bit TrueColor display rather than a 12- or 16-bit display. Some customers have found that the 8-bit display will work, but with the side effect of the expected color swapping between windows.

3) Invoke MATLAB without the Java Virtual Machine by using the following command at the UNIX prompt:

 matlab -nojvm

Note that this method will not make some Java dependent features available. See the Related Solution for more information.