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actions duration. A larger frame cache size and increased system memory usage can also
cause the overall system performance to degrade if there is not enough physical RAM to
hold the frame caches.
8.1.2.6 Video Codec
Experiment Builder supports playing video files that are compatible with VFW (video for
windows) and XVID encoded files. In each experiment, the user can load either VFM or
XVID video files into the library manager, but not both.
It is important to note that the video quality and playback performance will vary
depending on the codec used to compress the video files. Our internal tests have shown
that XVID video files perform much better than VFW avi files as the XVID loader runs
faster than the VFW loaders.
To play XVID encoded files, the user should convert the original video files with the
accompanying Split AVI tool with the video compressor set to "Xvid MPEG-4 codec"
(see "Video Experiments" in the html version of this document).
Please note that the "Xvid MPEG-4 codec" is not installed by default. To install the
XVID codec, go to the directory where the Experiment Builder software is installed, e.g.,
"C:\Program Files\SR Research\Experiment Builder". Select the xvid.inf file in the
"\VideoHandlers" folder and click the right mouse button to bring up a popup menu.
Select "Install" option. Click "Yes" button in the following "Digital Signature Not
Found" dialog box to continue the installation. This only needs to be done once on a
given display computer.
To play VFW video clips, choose other video codecs from the Split AVI compressor list it is a known issue that the not all VFW files are recognized and loadable into the library.
In addition, the performance of video files converted by different video codecs varies.
Users may try the Divx (http://www.divx.com/divx/play/download/) or MCMP/Mjpeg
codecs (http://www.leadcodecs.com/Codecs/LEAD-MCMP-MJPEG.htm) for VFW
codecs with good performance.
If the user deploys the experiment project and runs it on a different deployment computer,
please make sure that codec used to test run the video experiment is also installed on the
deployment computer as well; otherwise, the deployed experiment will not run. Please
also note that it is a known issue that the AVI converter may drop the last frame during
conversion when using the XVID encoder. Therefore, the user may add one extra frame
to each clip when authorizing video clips. The user can then set the "Frame List" attribute
of the video resource to the intended frame number, regardless whether the last frame is
dropped or not.
8.1.2.7 Playing Video Clips with Audio
For those video clips with sound, the "Split Avi" program splits the video stream from the
audio stream in the original video file and saves each stream in a separate file. Now the
user has two files, one for sound and one for video. To put the sound back into the video
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