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Core Image Concepts

Core Image is an extensible architecture available starting in Mac OS X v10.4 for near real-time, pixel-accurate image processing of graphics as well as video. You can perform the following types of operations by using filters that are bundled in Core Image or that you or another developer create:

• Crop images.

• Correct color, such as perform white point adjustment.

• Apply color effects, such as sepia tone.

• Blur or sharpen images.

• Composite images.

• Warp or transform the geometry of an image.

• Generate color, checkerboard patterns, Gaussian gradients, and other pattern images.

• Add transition effects to images or video.

• Provide real-time color adjustment on video.

Figure 1-1 gives a general idea of where Core Image fits with other graphics technologies in Mac OS X. Core Image is integrated with these technologies, allowing you to use them together to achieve a wide range of results. For example, you can use Core Image to process images created in Quartz 2D (Core Graphics) and textures created in OpenGL. You can also apply Core Image filters to video played using Core Video.

This chapter provides an overview of the Core Image technology and describes how you can use the programming interface in your application. It also discusses how Core Image works behind the scenes to achieve fast, stunning, near real-time image processing.

Contents:

Core Image and the GPU
Filter Clients and Filter Creators
The Processing Path
Coordinate Spaces
The Region of Interest
Executable and Nonexecutable Filters
Color Components and Premultiplied Alpha
See Also

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