javax.media.jai

The geometric relationship between the source and destination images will be determined by the specific behavior of the methods backwardMapRect() and forwardMapRect() the implementations of which must be provided by a subclass.

The location of the source pixel corresponding to a given destination pixel is determined by the aforementioned backward mapping transformation. The value of the destination pixel is then calculated by interpolating the values of a set of source pixels at locations in the vicinity of the backward mapped destination pixel location according to the requirements of a specified interpolation algorithm.

A "bin" is a container, where each element stores the total number of pixel samples of an image whose values lie within a given range.

The RGB-to-IHS transformation is defined by the equations:

• I = (R+G+B)/3
• S = 1-min(R, G, B)/I
• H = G > B ? h : 2*PI - h, where
  h = cos^-1{[(R-G)+(R-B)]/2[(R-G)²+ (R-G)(G-B)]^1/2}

The ImageLayout class encapsulates three types of information about an image:

• The image bounds, comprising the min X and Y coordinates, image width, and image height;
• The tile grid layout, comprising the tile grid X and Y offsets, the tile width, and the tile height; and
• The SampleModel and ColorModel of the image.

Each of these parameters may be set individually, or left unset. An unset parameter will cause the corresponding value of a given RenderedImage to be used.

InterpolationBicubic is a subclass of Interpolation that performs interpolation using the piecewise cubic polynomial:

 r(x) = (a + 2)|x|^3 - (a + 3)|x|^2         +  1 , 0 <= |x| < 1
 r(x) =       a|x|^3 -      5a|x|^2 + 8a|x| - 4a , 1 <= |x| < 2
 r(x) = 0                                        , otherwise
 

A neighborhood extending one sample to the left of and above the central sample, and two samples to the right of and below the central sample is required to perform bicubic interpolation.

This implementation creates an InterpolationTable whose integer coefficients have eight bits of precision to the right of the binary point.

The diagrams below illustrate the pixels involved in one-dimensional interpolation.

InterpolationBicubic2 is a subclass of Interpolation that performs interpolation using the piecewise cubic polynomial:

 r(x) = (a + 2)|x|^3 - (a + 3)|x|^2         +  1 , 0 <= |x| < 1
 r(x) =       a|x|^3 -      5a|x|^2 + 8a|x| - 4a , 1 <= |x| < 2
 r(x) = 0                                        , otherwise
 

This class allows programmers to use the syntax:

 import javax.media.jai.JAI;
 RenderedOp im = JAI.create("convolve", paramBlock, renderHints);
 

A KernelJAI is characterized by its width, height, and origin, or key element.

The primary use of this image factory is as a utility class in implementing operations which generate only non-image data via the use of PropertyGenerators.

An interface definition to aid in the automatic loading of user-defined JAI operations.

All concrete classes that implement this interface can register by listing themselves in the "META-INF/services/javax.media.jai.OperationRegistrySpi" file that can be found in the classpath (this file is often contained in a jar file along with the class files).

A perspective transformation is capable of mapping an arbitrary quadrilateral into another arbitrary quadrilateral, while preserving the straightness of lines.

This is the fundamental base class of Java Advanced Imaging (JAI) that represents a two-dimensional RenderedImage.

This class provides a home for the information and functionalities common to all the JAI classes that implement the RenderedImage interface, such as the image's layout, sources, properties, etc.

PointOpImage is intended as a convenient superclass for OpImages that only need to look at each destination pixel's corresponding source pixels.

The interface includes the getProperty() and getPropertyNames() methods familiar from the RenderedImage and RenderableImage interfaces. Classes which implement this interface should do so in a manner which treats the property names as case-retentive.

The image may be constructed from a RenderedImage or from an imaging chain in either the rendered or renderable mode.

SourcelessOpImage is intended as a convenient superclass for OpImages that have no source image.

TileCache provides a mechanism by which an OpImage may cache its computed tiles.

TiledImage is the main class for writable images in JAI.

Since the public methods of this class all derive from Graphics2D, they are not commented individually.

The ColorModel for the canvas will be that of the associated TiledImage unless that ColorModel is null.

If multithreading is used then the implementation of the interface must be thread-safe.

The output image will have a single tile, regardless of the ImageLayout settings passed to the constructor.

The central method of a Warp is warpSparseRect(), which returns the source pixel positions for a specified (subdivided) rectangular region of the output.

As in the Interpolation class, pixel positions are represented using scaled integer coordinates, yielding subpixel accuracy but still allowing the use of integer arithmetic.

The image warp is specified by a Warp object and an Interpolation object.

Subclasses of WarpOpImage may choose whether they wish to implement the cobbled or non-cobbled variant of computeRect by means of the cobbleSources constructor parameter.

The transform is specified as a mapping from destination space to source space.