On
this page are some sample JMF
programs each of which is written as a Java
applet. In each case there is a link to the html file to run the
applet as well as a link to the Java source code itself for viewing and
downloading.
The functionality of each of the applets is trivial but the kind of
video processing carried out in each case is typical of the sort of
thing researchers want to do - read from a movie file,
perform some
processing and put the processed frame back into the video stream to
display along with the original.
The input and output processors are synchronised with the input being
the master controller. Also interaction with a GUI component (in this
case a slider bar to set a threshold) is included in the application.
Typically an example will
either use just the current frame or the current and buffered
previous frames to produce the current output
frame (such as, for example, computing frame difference).
Example 1. Frame thresholding
The program displays both the original frame and
the thresholded frame within a JInternalFrame
which is added to the applet container. The threshold value can be
selected with a slider.
To run the applet click on Movie
frame threshold applet
To view/download the source code click on MovieFrameThresholdApplet.java
Example 2. Frame difference thresholding
As above but this program thresholds the frame difference (by buffering
the previous frame) so that only moving regions are highlighted.
To run the applet click on Movie
frame difference applet
To view/download the source code click on MovieFrameDifferenceApplet.java
Example 3. Displaying individual colour channels
In this program, indiviudal R,G,B,Y,U or V channels can be displayed
along with the original sequence.
To run the applet click on Colour
channel select applet
To view/download the source code click on MovieFrameRGBtoYUVApplet.java
NOTE 1. To run
JMF in
an applet can be a bit fiddly. If you get a java.lang.NoClassDefFoundError it
means that you probably installed your current jre
after you installed JMF. In this case you need to manually copy the jmf.jar file to the <JDK>/jre/lib/ext
directory being sure to check that this jre is the one called by your
browser's plug-in! (You do this by selecting the 'Java Plug-in' icon
from the control panel and then select the 'Advanced' tab which will
enable you to point your browser at whichever jre you like).
NOTE 2. There
are a
more extensive set of JMF programs on Sun's JMF
Solutions page.
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