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<P></P></DD></DL><A name=51162>
<H2>12.5 <IMG src="Client-Server Imaging.files/space.gif">Running Remote
Imaging</H2></A>To run remote imaging in JAI, you have to do the following:
<P>
<UL>1. Create a security policy file
<P>2. Start the RMI registry
<P>3. Start the remote image server
<P>4. Run the local application
<P></P></UL>These four steps are explained in more detail in the following
sections.
<P><A name=54942>
<H3>12.5.1 <IMG src="Client-Server Imaging.files/space.gif">Step 1: Create a
Security Policy File</H3></A>The default RMI security policy implementation is
specified within one or more policy configuration files. These configuration
files specify what permissions are allowed for code from various sources.
There is a default system-wide policy file and a single user policy file. For
more information on policy files and permissions, see:
<P><PRE> http://java.sun.com/products/jdk/1.2/docs/guide/security/
PolicyFiles.html
http://java.sun.com/products/jdk/1.2/docs/guide/security/
permissions.html
</PRE>The policy file is located in the base directory where Java Advanced
Imaging is installed. If <CODE>$JAI</CODE> is the base directory where Java
Advanced Imaging is installed, use any simple text editor to create a text
file named <CODE>$JAI/policy</CODE> containing the following:
<P><PRE> grant {
// Allow everything for now
permission java.security.AllPermission;
};
</PRE>Note that this policy file is for testing purposes only.
<P><A name=55056>
<H3>12.5.2 <IMG src="Client-Server Imaging.files/space.gif">Step 2: Start the
RMI Registry</H3></A>The RMI registry is a simple server-side name server that
allows remote clients to get a reference to a remote object. Typically, the
registry is used only to locate the first remote object an application needs
to talk to. Then that object in turn provides application-specific support for
finding other objects.
<P>
<HR noShade>
<B>Note:</B> Before starting the rmiregistry, make sure that the shell or
window in which you will run the registry either has no <CODE>CLASSPATH</CODE>
set or has a <CODE>CLASSPATH</CODE> that does not include the path to any
classes you want downloaded to your client, including the stubs for your
remote object implementation classes.
<HR noShade>
To start the registry on the server, log in to the remote system where the
image server will be running and execute the <CODE>rmiregistry</CODE> command.
<P>For example, in the <STRONG>Solaris</STRONG> operating environment using a
Bourne-compatible shell (e.g., /bin/sh):
<P><PRE> $ unset CLASSPATH
$ rmiregistry &
</PRE>Note that the <CODE>CLASSPATH</CODE> environment variable is
deliberately not set.
<P>For example, on <STRONG>Windows 95</STRONG> or <STRONG>Windows NT</STRONG>:
<P><PRE> start rmiregistry
</PRE>If the <CODE>start</CODE> command is not available, use
<CODE>javaw</CODE>.
<P><A name=54962>
<H3>12.5.3 <IMG src="Client-Server Imaging.files/space.gif">Step 3: Start the
Remote Image Server</H3></A>While still logged in to the remote server system,
set the <CODE>CLASSPATH</CODE> and <CODE>LD_LIBRARY_PATH</CODE> environment
variables as required for JAI (see the <CODE>INSTALL</CODE> file) and start
the remote imaging server. For example:
<P><PRE> $ CLASSPATH=$JAI/lib/jai.jar:\
$JAI/lib/mlibwrapper_jai.jar
$ export CLASSPATH
$ LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$JAI/lib
$ export LD_LIBRARY_PATH
$ java \
-Djava.rmi.server.codebase=\
file:$JAI/lib/jai.jar \
-Djava.rmi.server.useCodebaseOnly=false \
-Djava.security.policy=file:$JAI/policy \
com.sun.media.jai.rmi.RMIImageImpl
</PRE>For example, when the above steps are executed on a machine with IP
address 123.456.78.90 the following is printed:
<P><PRE> Server: using host 123.456.78.90 port 1099
Registering image server as
"rmi://123.456.78.90:1099/RemoteImageServer".
Server: Bound RemoteImageServer into
the registry.
</PRE><A name=54969>
<H3>12.5.4 <IMG src="Client-Server Imaging.files/space.gif">Step 4: Run the
Local Application</H3></A>After completing steps 1 through 3, you are ready to
run the local application. When running the local application, make sure that
the <CODE>serverName</CODE> parameter of any RemoteImage constructors
corresponds to the machine on which the remote image server is running. For
example, if the machine with IP address 123.456.78.90 above is named
<CODE>myserver</CODE>, the <CODE>serverName</CODE> parameter of any
<CODE>RemoteImage()</CODE> constructors should be <CODE>"myserver"</CODE>.
<P><A name=55174>
<H2>12.6 <IMG src="Client-Server Imaging.files/space.gif">Internet Imaging
Protocol (IIP)</H2></A>There are two JAI operations that support Internet
Imaging Protocol (IIP) operations. Two separate operations provide client-side
support of the Internet Imaging Protocol. These operations, <CODE>IIP</CODE>
and <CODE>IIPResolution</CODE>, request an image from an IIP server then
create either a RenderedImage or a RenderableImage.
<P><A name=55178>
<H3>12.6.1 <IMG src="Client-Server Imaging.files/space.gif">IIP
Operation</H3></A>The <CODE>IIP</CODE> operation provides client-side support
of the Internet Imaging Protocol (IIP) in both the rendered and renderable
modes. It creates a <CODE>RenderedImage</CODE> or a
<CODE>RenderableImage</CODE> based on the data received from the IIP server,
and optionally applies a sequence of operations to the created image.
<P>The operations that may be applied and the order in which they are applied
are defined in section 2.2.1.1 of the <EM>Internet Imaging Protocol
Specification</EM> version 1.0.5. Some or all of the requested operations may
be executed on the IIP server if it is determined that the server supports
such operations. Any of the requested operations not supported by the server
will be executed on the host on which the operation chain is rendered.
<P>The processing sequence for the supplied operations is as follows:
<P>
<UL>
<LI>Filtering (blur or sharpen)
<P></P></LI></UL>
<UL>
<LI>Tone and color correction ("color twist")
<P></P></LI></UL>
<UL>
<LI>Contrast adjustment
<P></P></LI></UL>
<UL>
<LI>Selection of source rectangle of interest
<P></P></LI></UL>
<UL>
<LI>Spatial orientation (rendering-independent affine transformation)
<P></P></LI></UL>
<UL>
<LI>Selection of destination rectangle of interest
<P></P></LI></UL>
<UL>
<LI>Rendering transformation (renderable mode only)
<P></P></LI></UL>
<UL>
<LI>Transposition (rotation and/or mirroring).
<P></P></LI></UL>As indicated, the rendering transformation is performed only
in renderable mode processing. This transformation is derived from the
AffineTransform supplied in the RenderContext when rendering actually occurs.
Rendered mode processing creates a RenderedImage which is the default
rendering of the RenderableImage created in renderable mode processing.
<P>The <CODE>IIP</CODE> operation takes 14 parameters.
<P>
<TABLE cellPadding=3 border=3>
<CAPTION><FONT size=-1><B></B></FONT></CAPTION>
<TBODY>
<TR vAlign=top>
<TH><A name=55324>Parameter </A>
<TH><A name=55326>Type </A>
<TH><A name=55328>Description </A>
<TR vAlign=top>
<TD><A name=55330>URL</A><BR>
<TD><A name=55332>String</A><BR>
<TD><A name=55334>The URL of the IIP image</A><BR>
<TR vAlign=top>
<TD><A name=55336>subImages</A><BR>
<TD><A name=55338>int[]</A><BR>
<TD><A name=55340>The sub-images to be used by the server for images at
each resolution level</A><BR>
<TR vAlign=top>
<TD><A name=55342>filter</A><BR>
<TD><A name=55344>Float</A><BR>
<TD><A name=55346>The filtering value</A><BR>
<TR vAlign=top>
<TD><A name=55424>colorTwist</A><BR>
<TD><A name=55426>float[]</A><BR>
<TD><A name=55428>The color twist matrix</A><BR>
<TR vAlign=top>
<TD><A name=55418>contrast</A><BR>
<TD><A name=55420>Float</A><BR>
<TD><A name=55422>The contrast value</A><BR>
<TR vAlign=top>
<TD><A name=55412>sourceROI</A><BR>
<TD><A name=55414>Rectangle2D.Float</A><BR>
<TD><A name=55416>The source rectangle of interest in
rendering-independent coordinates</A><BR>
<TR vAlign=top>
<TD><A name=55406>transform</A><BR>
<TD><A name=55408>AffineTransform</A><BR>
<TD><A name=55410>The rendering-independent spatial orientation
transform</A><BR>
<TR vAlign=top>
<TD><A name=55400>aspectRatio</A><BR>
<TD><A name=55402>Float</A><BR>
<TD><A name=55404>The aspect ratio of the destination image</A><BR>
<TR vAlign=top>
<TD><A name=55394>destROI</A><BR>
<TD><A name=55396>Rectangle2D.Float</A><BR>
<TD><A name=55398>The destination rectangle of interest in
rendering-independent coordinates</A><BR>
<TR vAlign=top>
<TD><A name=55388>rotation</A><BR>
<TD><A name=55390>Integer</A><BR>
<TD><A name=55392>The counterclockwise rotation angle to be applied to
the destination</A><BR>
<TR vAlign=top>
<TD><A name=55382>mirrorAxis</A><BR>
<TD><A name=55384>String</A><BR>
<TD><A name=55386>The mirror axis</A><BR>
<TR vAlign=top>
<TD><A name=55376>ICCProfile</A><BR>
<TD><A name=55378>color.ICC_Profile</A><BR>
<TD><A name=55380>The ICC profile used to represent the color space of
the source image</A><BR>
<TR vAlign=top>
<TD><A name=55370>JPEGQuality</A><BR>
<TD><A name=55372>Integer</A><BR>
<TD><A name=55374>The JPEG quality factor</A><BR>
<TR vAlign=top>
<TD><A name=55364>JPEGTable</A><BR>
<TD><A name=55366>Integer</A><BR>
<TD><A name=55368>The JPEG compression group index
number</A><BR></TR></TBODY></TABLE>
<P>The <CODE>URL</CODE> parameter specifies the URL of the IIP image as a
<CODE>java.lang.String</CODE>. It must represent a valid URL and include any
required FIF or SDS commands. It cannot be null.
<P>The <CODE>subImages</CODE> parameter optionally indicates the sub-images to
be used by the server to get the images at each resolution level. The values
in this <CODE>int</CODE> array cannot be negative. If this parameter is not
specified, or if the array is too short (length is 0), or if a negative value
is specified, this operation will use the zeroth sub-image of the resolution
level actually processed.
<P>The <CODE>filter</CODE> parameter specifies a blur or sharpen operation; a
positive value indicates sharpen and a negative value blur. A unit step should
produce a perceptible change in the image. The default value is 0 which
signifies that no filtering will occur.
<P>The <CODE>colorTwist</CODE> parameter represents a 4 x 4 matrix stored in
row-major order and should have an array length of at least 16. If an array of
length greater than 16 is specified, all elements from index 16 and beyond are
ignored. Elements 12, 13, and 14 must be 0. This matrix will be applied to the
(possibly padded) data in an intermediate normalized PhotoYCC color space with
a premultiplied alpha channel. This operation will force an alpha channel to
be added to the image if the last column of the last row of the color twist
matrix is not 1.0F. Also, if the image originally has a grayscale color space
it will be cast up to RGB if casting the data back to grayscale after applying
the color twist matrix would result in any loss of data. The default value is
null.
<P>The <CODE>contrast</CODE> parameter specifies a contrast enhancement
operation with increasing contrast for larger value. It must be greater than
or equal to 1.0F. A value of 1.0F indicates no contrast adjustment. The
default value is 1.0F.
<P>The <CODE>sourceROI</CODE> parameter specifies the rectangle of interest in
the source image in rendering-independent coordinates. The intersection of
this rectangle with the rendering-independent bounds of the source image must
equal itself. The rendering-independent bounds of the source image are defined
to be (0.0F, 0.0F, r, 1.0F) where r is the aspect ratio (width/height) of the
source image. Note that the source image will not in fact be cropped to these
limits but values outside of this rectangle will be suppressed.
<P>The <CODE>transform</CODE> parameter represents an affine backward mapping
to be applied in rendering-independent coordinates. Note that the direction of
transformation is opposite to that of the AffineTransform supplied in the
RenderContext which is a forward mapping. The default value of this transform
is the identity mapping. The supplied AffineTransform must be invertible.
<P>The <CODE>aspectRatio</CODE> parameter specifies the rendering-independent
width of the destination image and must be positive. The rendering-independent
bounds of the destination image are (0.0F, 0.0F, aspectRatio, 1.0F). If this
parameter is not provided, the destination aspect ratio defaults to that of
the source.
<P>The <CODE>destROI</CODE> parameter specifies the rectangle of interest in
the destination image in rendering-independent coordinates. This rectangle
must have a non-empty intersection with the rendering-independent bounds of
the destination image but is not constrained to the destination image bounds.
<P>The <CODE>rotation</CODE> parameter specifies a counter-clockwise rotation
angle of the destination image. The rotation angle is limited to 0, 90, 180,
or 270 degrees. By default, the destination image is not rotated.
<P>The <CODE>mirrorAxis</CODE> parameter may be null, in which case no
flipping is applied, or a String of <CODE>x</CODE>, <CODE>X</CODE>,
<CODE>y</CODE>, or <CODE>Y</CODE>.
<P>The <CODE>ICCProfile</CODE> parameter may only be used with client-side
processing or with server-side processing if the connection protocol supports
the ability to transfer a profile.
<P>The <CODE>JPEGQuality</CODE> and <CODE>JPEGTable</CODE> parameters are only
used with server-side processing. If provided, <CODE>JPEGQuality</CODE> must
be in the range [0,100] and <CODE>JPEGTable</CODE> in [1,255].
<P>There is no source image associated with this operation.
<P><A
href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Client-server.doc.html#56227">Listing
12-3</A> shows a code sample for an <CODE>IIP</CODE> operation.
<P><CAPTION><FONT size=-1><B><A name=56227>
<CENTER><FONT size=-1><B><I>Listing 12-3 </I><IMG
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