Xerox ColorQube 9201, Руководство системного администратора

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General Setup
Xerox ColorQube™ 9201/9202/9203
System Administrator Guide
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• TIFF Specification Supplement 2 (New JPEG) - this is an update to the TIFF 6.0
specification and provides a more fault-free JPEG compression algorithm, but may not be
compatible with older graphics software.
• LZW - this is a lossless compression method yielding very high compression efficiency, LZW
works best for files containing repetitive data, such as is the case with text and monochrome
images. LZW has long been associated with TIFF and GIF images. This compression
algorithm was widely used in Adobe Photoshop, until version 6, and Adobe Acrobat, until
version 5.
8. In the PDF & PDF/A Settings area, select the following compression types for PDF and PDF/A
documents:
a. For Optimization for Fast Web Viewing , check the [Enabled] checkbox.
If enabled, this option will create linearized PDF files. Linearized PDF files allow the first page
of the PDF file to be displayed in a user's web browser, before the entire file is downloaded
from the web server. This fast first page display helps to alleviate Internet user frustration in
waiting for an entire file to download before displaying the file's contents.
This option will produce relatively small files with a very short encoding delay per page,
however the image detail may appear more grainy when printed.
Note: Regarding Searchable PDF and PDF/A: If this option is available, by enabling the selection
you will provide Workflow Scanning, E-mail, and Internet Fax users with the ability to choose
[Searchable] as an option for their PDF and PDF/A file formats. The Searchable Format provides a
second layer of data with the text of the scanned document. The second layer is converted to an
optical character readable format, enabling the text of the document to be searched on, copied,
and pasted, as desired.
b. JBIG is a standard algorithm for lossless compression of bi-level images (two color images),
specializing in the preservation of thin lines. JBIG2 compression is usually used for text and
halftone documents, and is claimed to be able to compress scanned documents up to 10
times smaller than with TIFF G4. A further claim is that it allows scanned manuals, books,
check images, and other document types to be viewed and manipulated efficiently over the
Internet. This method yields a very small black and white file size with fast viewing
performance. This compression format requires Acrobat 5, with PDF version 1.4 or greater.
There are two encoding methods for JBIG2, select both of the following options for optimal
compression:
• Enable Arithmetic Encoding
• Enable Huffman Encoding
Select one option for good compression and improved speed, if neither is selected, there will be no
compression or optimal speed.
c. For Flate Compression , check the [Enabled] checkbox.
Flate Compression is a lossless compression format that combines LZ77 (the first LZW) and
adaptive Huffman encoding (RFC 1951). Huffman compression is a lossless algorithm ideal
for compressing text. LZ77 works well with files containing lots of repetitive data, such as text
and monochrome image (TIFF and GIF) files. When used for PDF documents, Flate
compression is applied after JPEG compression. It is also used in place of G3 compression for
monochrome PDF images in Photo and Magazine mode.
d. For MRC Compression , check the [Enabled] checkbox to divide the scanned image based on
content, and then compress each area in the optimal manner for that image area. This
option allows for smaller output files with better image quality.