Generating a color tableIllustrator generates a color table for GIF and PNG-8 images based on the color options you set for optimization. You choose a method for generating the color table from the Color Reduction menu and specify the number of colors you want in the color table in the Colors text box. (See Optimization options for GIF and PNG-8 formats.) You can choose from the following methods for generating color tables: Perceptual Creates a custom color table by giving priority to colors for which the human eye has greater sensitivity. Selective Creates a color table similar to the Perceptual color table, but favoring broad areas of color and the preservation of Web colors. This color table usually produces images with the greatest color integrity. Selective is the default option. Adaptive Creates a custom color table by sampling colors from the spectrum appearing most commonly in the image. For example, an image with only the colors green and blue produces a color table made primarily of greens and blues. Most images concentrate colors in particular areas of the spectrum. Web Uses the standard 216-color color table common to the Windows and Mac OS 8-bit (256-color) palettes. This option ensures that no browser dither is applied to colors when the image is displayed using 8-bit color. (This palette is also called the Web-safe palette.) Using the Web palette can create larger files, and is recommended only when avoiding browser dither is a high priority. Custom Preserves the current perceptual, selective, or adaptive color table as a fixed palette that does not update with changes to the image. Note: Other color tables appear in the menu if you have saved them previously. |