我试图在Matlab中运行使用Psychtoolbox和OpenGL的代码。抛出下述错误的命令是：
PsychJavaTrouble
AssertOpenGL
这是我的规格：
OS: Ubuntu 14.04 LTS, 64bit
Processor: Intel Core i5-2450M CPT @ 2.50GHz x 4
Graphics: Intel Sandybridge Mobile
Matlab Version: Matlab 64-Bit (Version 3.0.11 - Build date: Apr 6 2014)
Psychophysics version installed: 3
Installation methodology:
1. sudo apt-get install psychtoolbox in Terminal
2. updated it via UpdatePsychToolbox command in Matlab console
这是错误消息：
PsychJavaTrouble: Will now try to add the PsychJava folder to Matlabs dynamic
classpath...
Warning: "/home/lillian/Desktop/Matlab/Mona_Lisa/Psychtoolbox/PsychJava" is already
specified on static java path.
> In javaclasspath>local_validate_dynamic_path at 285
In javaclasspath>local_javapath at 182
In javaclasspath at 119
In javaaddpath at 71
In PsychJavaTrouble at 86
In ReverseCorrelationFaces at 2
PsychJavaTrouble: Added PsychJava folder to dynamic class path. Psychtoolbox Java
commands should work now!
PTB-INFO: Display ':0' : X-Screen 0 : Assigning primary output as 0 with RandR-CRTC
0 and GPU-CRTC 0.
PTB-INFO: This is Psychtoolbox-3 for GNU/Linux X11, under Matlab 64-Bit (Version
3.0.11 - Build date: Apr 6 2014).
PTB-INFO: No low-level controllable GPU on screenId 0. Beamposition timestamping and
other special functions disabled.
PTB-INFO: Failed to enable realtime-scheduling [Operation not permitted]!
PTB-DEBUG:PsychOSGetSwapCompletionTimestamp: Invalid return values ust = 0, msc = 0
from call with success return code (sbc = 304)! Failing with rc = -2.
PTB-DEBUG:PsychOSGetSwapCompletionTimestamp: This likely means a driver bug or
malfunction, or that timestamping support has been disabled by the user in the
driver!
PTB-INFO: OpenGL-Renderer is Intel Open Source Technology Center :: Mesa DRI
Intel(R) Sandybridge Mobile :: 3.0 Mesa 10.1.3
PTB-INFO: VBL startline = 768 , VBL Endline = -1
PTB-INFO: Will try to use OS-Builtin OpenML sync control support for accurate Flip
timestamping.
PTB-INFO: Measured monitor refresh interval from VBLsync = 16.685075 ms [59.933804
Hz]. (297 valid samples taken, stddev=0.310528 ms.)
PTB-INFO: Reported monitor refresh interval from operating system = 16.646968 ms
[60.070999 Hz].
PTB-INFO: Small deviations between reported values are normal and no reason to
worry.
WARNING: Couldn't compute a reliable estimate of monitor refresh interval! Trouble
with VBL syncing?!?
----- ! PTB - ERROR: SYNCHRONIZATION FAILURE ! ----
One or more internal checks (see Warnings above) indicate that synchronization
of Psychtoolbox to the vertical retrace (VBL) is not working on your setup.
This will seriously impair proper stimulus presentation and stimulus presentation
timing!
Please read 'help SyncTrouble' for information about how to solve or work-around the
problem.
You can force Psychtoolbox to continue, despite the severe problems, by adding the
command
Screen('Preference', 'SkipSyncTests', 1); at the top of your script, if you really
know what you are doing.
Error using Screen
See error message printed above.
Error in ReverseCorrelationFaces (line 81)
window=Screen('OpenWindow', windowNum);
我错过了什么？一套？我的硬件不行吗？我无法想出这个错误。
所以..深埋在DownloadPsychtoolbox.m文件中找到here（参见安装说明here），显然是Psychtoolbox需要特殊SDK的指令。超级烦人。我永远不会再使用这个工具箱，因为它使用起来太多了。但这是导致Screen调用失败的缺失
缺少SDK下载链接：http://docs.gstreamer.com/display/GstSDK/Installing+on+Windows