Adobe Acrobat 8 3D - Manual (Page 119)

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Sales Plan
Kahili Mountain Coffee
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ADOBE ACROBAT 3D VERSION 8
User Guide
Suitable compression methods for different art types
A. ZIP B. JPEG C. CCITT D. Run Length
You can choose from the following compression methods:
ZIP Works well on images with large areas of single colors or repeating patterns, and for black-and-white images
that contain repeating patterns. Acrobat supports only 8-bit ZIP compression, which is lossless; that is, data is not
removed to reduce file size, so image quality is not affected.
Note: Adobe implementation of the ZIP filter is derived from the zlib package of Jean-loup Gailly and Mark Adler, whose
generous assistance we gratefully acknowledge.
JPEG Suitable for grayscale or color images, such as continuous-tone photographs. JPEG is lossy, which means that
it removes image data and may reduce image quality; however, it attempts to reduce file size with the minimum loss
of information. Because JPEG compression eliminates data, it can achieve much smaller file sizes than ZIP
compression.
CCITT Available only for monochrome bitmap images. CCITT (Consultative Committee on International Teleg­
raphy and Telephony) compression is appropriate for black-and-white images and any images scanned with an image
depth of 1 bit. Group 4 is a general-purpose method that produces good compression for most monochrome images.
Group 3, used by most fax machines, compresses monochrome images one row at a time.
Run Length Produces the best results for images that contain large areas of solid white or black.