Xerox 721P87491 manual Creating the necessary PostScript Ccitt Group 3, Scan order and rotation

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POSTSCRIPT

Creating the necessary PostScript CCITT Group 3 and 4

You can embed an image that is compressed to CCITT group 4 specifications in the PostScript. You need to add several standard PostScript statements before the embedded image to provide the image parameters, and to properly use the FaxDecode filter.

Images use the PostScript image, imagemask, and filter (CCITTFaxDecode filter) operators. Refer to the Adobe PostScript Language Reference Manual for the proper syntax, specifically the sections on the image and imagemask operators, the FaxDecode filter, and transformation matrixes.

The source parameter of the CCITTFaxDecode filter operator should be set to currentfile, and the bit/sample parameter of the image operator should be 1 (for a binary image) because this method of submission uses an embedded CCITT compressed image. Either form of the image and imagemask operators can be used; however, DocuPrint does not support any functionality in the dictionary form that exceeds the functionality available through the non-dictionary form of the operators.

Print performance related to image printing

Printing speed for CCITT G3/G4 documents is determined largely by the decompression and imaging time. The decompression time is correlated with the compression ratio (better compression means less time). The imaging time is correlated with the kind of scaling and rotation performed. Consequently, printing speed is dependent on the document characteristics.

Optimal performance for CCITT G3/G4 printing is obtained with a 1- to-1 scaling (for example, 300 dpi input resolution) and 0 degree rotation. DocuPrint software is optimized to provide good performance for the most frequently employed resolutions and rotations. For example: resolutions of 200 dpi [fax]; 240 dpi [IBM,etc.]; 400 dpi [extended fine fax]; and rotations of 0, 90, 180, or 270 degrees. Arbitrary scaling and/or rotation may impact performance.

Typical CCITT G3/G4 images have the fast scan direction along the short edge of the paper and DocuPrint images along the long edge of the paper. Therefore, in most cases, it is necessary to perform an image rotation of 90 degrees on the CCITT G3/G4 data.

It is beneficial to create and to store CCITT G3/G4 images with optimal scaling and rotation values for the target printer. These CCITT G3/G4 images, of reasonable compression ratios, typically print at or near rated printer speed.

Scan order and rotation

A scanned or sampled image is defined as a rectangular array of sample values, each representing some color. In a PostScript program, such an image is represented by a sequence of sample values obtained by scanning the image rectangle in row or column order.

XEROX DOCUPRINT NPS GUIDE TO USING PAGE DESCRIPTION LANGUAGES

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Contents Version 7.1 August 2000 721P87491 Page Ozone information Laser safetyOperation safety Conductor may result in risk of electrical shock. grounding Table of contents PostScript Index VippViii Conventions ContentsAbout this guide Introduction PostScript publications Related publicationsRelated information Vipp publication HP PCL 5 publicationsMaintaining image quality PCLOFF PCL 5 font support PCL 5 media supportPCL 5 fonts installed with NPS software PCL Copy command PCL command supportPJL commands Duplex PCL Copy command example PCL Copy command examplePCL Duplex commands DocuPrint NPS Collated HP LaserJet 4si PCL Duplex commandsPCL Job Separation command PCL media selection PCL Paper Source command tray assignmentPrecedence in selecting media PCL Offset Registration commands PCL Output Bin commandPCL 5 coding recommendations PCL 5c supportPCL 5c functions not applicable to DocuPrint NPS PCL 5c coding recommendationsLimitations for custom PCL 5c drivers Driver recommendations for PCL 5cFloating-point arithmetic and math operators Coordinate system default matrixImplementation-dependent operations Font Typeface FontsAdobe Type1 PostScript fonts User-defined fonts Loading fontsType 1 fonts Using Adobe Type 1 fontsProducing Type 1 fonts for use with DocuPrint Using a Type 1 font in a documentSystem Dict PostScript with embedded PJL commandsPostScript language extensions Server Dict User DictDfltkIdleArry needflush Status DictIdleTime Dictionary Nonstandard definitions Appearance consistency Printer resolution and resolution enhancementExamples of nonstandard definitions Statusdict UserdictDpi image Printed on a 300 dpi printer Printer imaging characteristics Proprietary PostScript extensions Font consistencyControl-D as binary data and end-of-job Control-Z and superfluous errorsSolution to control-Z and control-D problems Multiple jobs in one input file Simulated mixed plex DocuPrint NPS implementation of PostScript LevelStroke Printer Controller operationsScan conversion details Shapes FillImages Zero-width lines strokesCurved shapes Image quality Rendering of color and gray values transfer function Implementation limits PostScript printer description PPD filesQuantity Limit Description File operators and standard devicesImplementation limits PostScript VM limits Path limitsSetCacheDevice Device orientation and setscreen operatorArc to Bezier conversion-pathforall PostScript storage object size limitsObsolete operators-banddevice, framedevice, renderbands Scan order and rotation Creating the necessary PostScript Ccitt Group 3Print performance related to image printing Image orientation mismatch a PurposeImage orientation mismatch B 10.Image pixel sequence example Summary Considerations11.Scaling and resolution example Scan resolution and scaling12.PostScript with embedded image normal scan order MaxX exch def /minY exch def /minX exch def 14.Actual PostScript print Page Vipp Operating environment FunctionalityVipp line mode extension XGFNub Page Ccitt SymbolsIndex PCL PPD Index

721P87491 specifications

The Xerox 721P87491 is a remarkable printing device that showcases advanced technology tailored for professional environments, ensuring high-quality output and efficiency. Aimed at meeting the demands of busy offices, this model is recognized for its reliability and innovative features.

At the core of the Xerox 721P87491's appeal is its robust printing capabilities. It offers an impressive resolution, enabling the production of crisp and clear documents, whether in black and white or color. This high-resolution output is particularly essential for businesses that require detailed graphics, intricate charts, or professional-grade presentations.

One of the standout features of the Xerox 721P87491 is its impressive speed. It is designed to handle high-volume printing, significantly enhancing productivity in fast-paced work environments. With a rapid print speed per minute, users can expect swift processing of print jobs, ensuring that document delivery times are minimized.

The device also boasts advanced connectivity options. It supports both wired and wireless connections, allowing for seamless integration into a variety of office networks. This flexibility facilitates printing from multiple devices, including desktop computers, laptops, and mobile devices, enhancing overall workflow and collaboration within teams.

Additionally, the Xerox 721P87491 incorporates user-friendly interface options. With an intuitive touchscreen display, navigating the printer's functions becomes simpler. Users can easily access common features, adjust settings, and manage print jobs efficiently.

Another notable characteristic is its advanced security features. Given today's emphasis on data protection, the Xerox 721P87491 is equipped with robust security protocols to safeguard sensitive documents. It includes features like secure print, which holds documents until the authorized user enters a PIN, ensuring confidentiality in high-stakes environments.

Moreover, the Xerox 721P87491 demonstrates an emphasis on environmental sustainability. It is designed to be energy efficient, reducing power consumption during both idle and active states. The printer also supports duplex printing, which helps decrease paper use, contributing to a more sustainable office practice.

In summary, the Xerox 721P87491 is a versatile printing solution that merges efficiency, quality, and advanced technology. With high-speed printing, intuitive controls, robust security features, and a commitment to sustainability, it stands out as an excellent choice for businesses aiming to boost productivity while maintaining high standards. Its capabilities make it a worthy investment for any modern office environment.
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