href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#56858">Section 
  3.3.1, "Rendered Graphs</A>"). There are two ways of producing a rendering of 
  a <CODE>RenderedOp</CODE>: 
  <P>
  <UL>
    <LI>Implicit - Any call to a <CODE>RenderedImage</CODE> method on a 
    <CODE>RenderedOp</CODE> causes a rendering to be created. This rendering 
    will usually consist of a chain of <CODE>OpImage</CODE>s with a similar 
    geometry to the <CODE>RenderedOp</CODE> chain. It may have more or fewer 
    nodes, however, since the rendering process may both collapse nodes together 
    by recognizing patterns, and expand nodes by the use of the 
    <CODE>RenderedImageFactory</CODE> interface. The 
    <CODE>OperationRegistry</CODE> (described in <A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Extension.doc.html#47227">Chapter 
    14</A>) is used to guide the <CODE>RenderedImageFactory</CODE> selection 
    process.
    <P></P></LI></UL>
  <UL>
    <LI>Explicit - A call to <CODE>createInstance</CODE> effectively clones the 
    <CODE>RenderedOp</CODE> and its source <CODE>RenderedOp</CODE>s, resulting 
    in an entirely new Rendered chain with the same non-<CODE>RenderedOp</CODE> 
    sources (such as <CODE>TiledImage</CODE>s) as the original chain. The bottom 
    node of the cloned chain is then returned to the caller. This node will then 
    usually be implicitly rendered by calling <CODE>RenderedImage</CODE> methods 
    on it.
    <P></P></LI></UL><CODE>RenderedOp</CODE>s that have not been rendered may have 
  their sources and parameters altered. Sources are considered evaluated as soon 
  as they are connected to a <CODE>RenderedOp</CODE>. 
  <P><A name=55112>
  <H2>3.6 <IMG src="Programming in Java Advanced Imaging3.files/space.gif">JAI 
  API Operators</H2></A>The JAI API specifies a core set of image processing 
  operators. These operators provide a common ground for applications 
  programmers, since they can then make assumptions about what operators are 
  guaranteed to be present on all platforms. 
  <P>The general categories of image processing operators supported include: 
  <P>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55124">Point 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55826">Area 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#60616">Geometric 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#60618">Color 
    Quantization Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55610">File 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55692">Frequency 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55775">Statistical 
    Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#55826">Edge 
    Extraction Operators</A>
    <P></P></LI></UL>
  <UL>
    <LI><A 
    href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#63124">Miscellaneous 
    Operators</A>
    <P></P></LI></UL>The JAI API also supports abstractions for many common types 
  of image collections, such as time-sequential data and image pyramids. These 
  are intended to simplify operations on image collections and allow the 
  development of operators that work directly on these abstractions. 
  <P><A name=55124>
  <H3>3.6.1 <IMG 
  src="Programming in Java Advanced Imaging3.files/space.gif">Point 
  Operators</H3></A>Point operators allow you to modify the way in which the 
  image data fills the available range of gray levels. This affects the image's 
  appearance when displayed. Point operations transform an input image into an 
  output image in such a way that each output pixel depends only on the 
  corresponding input pixel. Point operations do not modify the spatial 
  relationships within an image. 
  <P><A 
  href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Programming-environ.doc.html#64590">Table 
  3-1</A> lists the JAI point operators.
  <P>
  <TABLE cellPadding=3 border=3>
    <CAPTION><FONT size=-1><B><A name=64590><I>Table 3-1 </I><IMG 
    src="Programming in Java Advanced Imaging3.files/sm-blank.gif" border=0> 
    Point Operators </A></B></FONT></CAPTION>
    <TBODY>
    <TR vAlign=top>
      <TH><A name=64596>Operator </A>
      <TH><A name=64598>Description </A>
      <TH><A name=64600>Reference </A>
    <TR vAlign=top>
      <TD><A name=64602>Absolute</A><BR>
      <TD><A name=64604>Takes one rendered or renderable source image, and 
        computes the mathematical absolute value of each pixel.</A><BR>
      <TD><A name=64609><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56159">page 
        177</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64611>Add</A><BR>
      <TD><A name=64613>Takes two rendered or renderable source images, and 
        adds every pair of pixels, one from each source image of the 
        corresponding position and band.</A><BR>
      <TD><A name=64618><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56366">page 
        166</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64620>AddCollection</A><BR>
      <TD><A name=64622>Takes a collection of rendered source images, and adds 
        every pair of pixels, one from each source image of the corresponding 
        position and band.</A><BR>
      <TD><A name=64627><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#68198">page 
        168</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64629>AddConst</A><BR>
      <TD><A name=64968>Takes a collection of rendered images and an array of 
        double constants, and for each rendered image in the collection adds a 
        constant to every pixel of its corresponding band.</A><BR>
      <TD><A name=64636><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56269">page 
        167</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64638>AddConstToCollection </A>
      <TD><A name=64978>Takes a collection of rendered images and an array of 
        double constants, and for each rendered image in the collection adds a 
        constant to every pixel of its corresponding band.</A><BR>
      <TD><A name=64645><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#69890">page 
        169</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64647>And</A><BR>
      <TD><A name=64988>Takes two rendered or renderable source images and 
        performs a bit-wise logical AND on every pair of pixels, one from each 
        source image, of the corresponding position and band.</A><BR>
      <TD><A name=64654><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56569">page 
        158</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64656>AndConst</A><BR>
      <TD><A name=65000>Takes one rendered or renderable source image and an 
        array of integer constants, and performs a bit-wise logical AND between 
        every pixel in the same band of the source and the constant from the 
        corresponding array entry.</A><BR>
      <TD><A name=64663><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56421">page 
        159</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64665>BandCombine</A><BR>
      <TD><A name=65010>Takes one rendered or renderable source image and 
        computes a set of arbitrary linear combinations of the bands using a 
        specified matrix.</A><BR>
      <TD><A name=64672><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Color.doc.html#51591">page 
        141</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64674>BandSelect</A><BR>
      <TD><A name=65030>Takes one rendered or renderable source image, chooses 
        N bands from the image, and copies the pixel data of these bands to the 
        destination image in the order specified.</A><BR>
      <TD><A name=64681><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#63344">page 
        185</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64683>Clamp</A><BR>
      <TD><A name=65036>Takes one rendered or renderable source image and sets 
        all the pixels whose value is below a low value to that low value and 
        all the pixels whose value is above a high value to that high value. The 
        pixels whose value is between the low value and the high value are left 
        unchanged.</A><BR>
      <TD><A name=64690><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#56747">page 
        184</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64692>ColorConvert</A><BR>
      <TD><A name=65046>Takes one rendered or renderable source image and 
        performs a pixel-by-pixel color conversion of the data.</A><BR>
      <TD><A name=64699><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Color.doc.html#51551">page 
        140</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64701>Composite</A><BR>
      <TD><A name=65056>Takes two rendered or renderable source images and 
        combines the two images based on their alpha values at each 
        pixel.</A><BR>
      <TD><A name=64708><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-enhance.doc.html#61005">page 
        243</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64710>Constant</A><BR>
      <TD><A name=65062>Takes one rendered or renderable source image and 
        creates a multi-banded, tiled rendered image, where all the pixels from 
        the same band have a constant value.</A><BR>
      <TD><A name=64717><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Acquisition.doc.html#72170">page 
        123</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64719>Divide</A><BR>
      <TD><A name=65072>Takes two rendered or renderable source images, and 
        for every pair of pixels, one from each source image of the 
        corresponding position and band, divides the pixel from the first source 
        by the pixel from the second source.</A><BR>
      <TD><A name=64726><A 
        href="http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Image-manipulation.doc.html#63828">page 
        171</A></A><BR>
    <TR vAlign=top>
      <TD><A name=64728>DivideByConst</A><BR>
      <TD><A name=65084>Takes one rendered source image and divides the pixel 
        values of the image by a constant.</A><BR>