I

ICC

See International Color Consortium .

image caching

A mechanism that accelerates screen redrawing during the editing process.

image link

A link on a Web page activated by clicking an image.

image map

An image on a Web page that has multiple links to another Web page or URL. Each link is called a hotspot. Image maps let you define circular, polygonal, or rectangular areas as links.

image size

The physical size and resolution of an image. The size of an image specifies the exact number of pixels that compose a picture.

ImageReady

A companion program to Photoshop, used to create dynamic Web graphics.

Indexed color image

A single-channel image, with 8 bits of color information per pixel. The index is a color lookup table containing up to 256 colors.

Indexed color mode

A color mode that uses a maximum of 256 colors to display full-color images. When you convert an image color to Indexed mode, Photoshop stores the color information as a color lookup table. You can then use a specific palette to display the image to match the colors as closely as possible to the original. Because it contains fewer colors, Indexed color mode creates smaller file sizes than the other color modes produce.

Info palette

The Photoshop palette that shows information about the current image. By default, the Info palette displays Actual Color and CMYK fields, the x and y coordinates of the position of the cursor, and the height and width of the selection. This palette can display values in different modes, including Web, HSB, Lab, Total Ink, and Opacity.

interlacing

A technique used to display a GIF image progressively on a Web page.

International Color Consortium (ICC)

An organization that sets standards for color management systems and components .

interpolation

In Photoshop, the setting for how the program resamples, or sizes, images.

inverse

In Photoshop, to reverse the selection; that is, to change the selected area to the portion that you did not select with a selection tool.

invert

To remap the brightness values of a channel to its opposite value. When you invert a channel, the white pixels with a value of 255 become black with a value of 0. Dark gray pixels in the channel with a value of 20, for example, will be remapped to a value of 235.