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Working with Images
Reading/Loading an Image
Drawing an Image
Creating and Drawing to an Image
Writing/Saving an Image
Trail: 2D Graphics
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Lesson: Working with Images

> As you have already learned from the Overview lesson, `Image`s are described by a width and a height, measured in pixels, and have a coordinate system that is independent of the drawing surface.

> There are a number of common tasks when working with images.

> - Loading an external GIF, PNG JPEG image format file into Java 2D™'s internal image representation.
> - Directly creating a Java 2D image and rendering to it.
> - Drawing the contents of a Java 2D image on to a drawing surface.
> - Saving the contents of a Java 2D image to an external GIF, PNG, or JPEG image file.

> This lesson teaches you the basics of loading, displaying, and saving images.

> The are two main classes that you must learn about to work with images:

> - The `java.awt.Image` class is the superclass that represents graphical images as rectangular arrays of pixels.
> - The `java.awt.image.BufferedImage` class, which extends the `Image` class to allow the application to operate directly with image data (for example, retrieving or setting up the pixel color). Applications can directly construct instances of this class.

> The `BufferedImage` class is a cornerstone of the Java 2D immediate-mode imaging API. It manages the image in memory and provides methods for storing, interpreting, and obtaining pixel data. Since `BufferedImage` is a subclass of `Image` it can be rendered by the `Graphics` and `Graphics2D` methods that accept an `Image` parameter.

> A `BufferedImage` is essentially an `Image` with an accessible data buffer. It is therefore more efficient to work directly with `BufferedImage`. A `BufferedImage` has a ColorModel and a Raster of image data. The ColorModel provides a color interpretation of the image's pixel data.

> The Raster performs the following functions:

> - Represents the rectangular coordinates of the image
> - Maintains image data in memory
> - Provides a mechanism for creating multiple subimages from a single image data buffer
> - Provides methods for accessing specific pixels within the image

> The basic operations with images are represented in the following sections:

> ### Reading/Loading an image

> > This section explains how to load an image from an external image format into a Java application using the Image I/O API

> ### Drawing an image

> > This section teaches how to display images using the `drawImage` method of the `Graphics` and `Graphics2D` classes.

> ### Creating and drawing To an image

> > This section describes how to create an image and how to use the image itself as a drawing surface.

> ### Writing/saving an image

> > This section explains how to save created images in an appropriate format.

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