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Jun 1, 1998 12:00 AM
Originally designed as core technology, RIPs are evolving into process solutions that can affect your bottomline success.
When Adobe first released PostScript in the early 1980s, few realized the significant impact it would have on printing and publishing. Prior to that, the term "RIP" was not automatically associated with a thriving printing process.
A RIP, as used today in our industry, is really an acronym for Raster Image Processor. According to its function, a raster image processor interprets an incoming PostScript language program, creates a display list that indicates how this program will be displayed on a page, and then creates rasters (or pixels) of the display list in the designated colors at the selected resolution for the ultimate imaging process.
The first RIP was developed as a way to take the PostScript information created on an Apple computer and print the file to a LaserWriter printer. The next implementation of RIPs took the same information and output it to a Linotype phototypesetter. Eventually, most of the major phototypesetter manufacturers followed the Linotype lead, creating RIP front-ends to either existing machines and/ or to new phototypesetting (now imagesetting) machines.
When Aldus (now part of Adobe) PageMaker was introduced, these new capabilities opened up the possibility of using these desktop computers to do a wider variety of publishing tasks. The capabilities of the first version (Level 1) were soon pushed to the limit. Features such as support for a large selection of fonts, bigger and more complex images, process color and trapping constituted problems for Level 1 PostScript.
Many vendors developed "workarounds" using application software modifications and hardware additions to the RIPs, trying to overcome limitations. In addition, the major prepress solution providers of the time (Crosfield, Hell and Scitex) implemented RIPs that would allow them to process those same desktop files through their existing CEPs systems. This also took advantage of the wealth of established features of these systems and, more importantly, the markets.
In 1982 Adobe announced PostScript Level 2, which addressed many of the problems that had come to light during the early implementations. As a result, new solutions were developed based on a "totally" PostScript workflow and CEPS workstations started to disappear from the market. The vendors redesigned their systems and processes to take advantage of the "best of both worlds."
While all output devices require a RIP to process PostScript, the RIPs themselves actually were produced by a limited number of companies. During this period (mid- to late 1980s), there were fewer than 12 companies producing RIPs, of which the three major players were Adobe, Hyphen and Harlequin.
The non-Adobe RIP manufacturers tried to overcome some of the inherent limitations of PostScript by developing workarounds in the RIPs. Unfortunately, while they addressed some of the problems, these RIPs were not necessarily created to conform to the Adobe rulebook. As a result, sometimes users would get peculiar results when running the same file through different RIPs. Over time, the field of RIP manufacturers began to shrink and the market began to stabilize.
Currently, the two major players in core RIP development are Adobe and Harlequin, although there are still others (Colorbus and 5D, for example) that develop and license RIP technology. Even though some RIPs are internally developed by the output device manufacturers, Adobe and Harlequin have the lion's share of the market. Overall, they produce compatible RIPs for the vast majority of printers, imagesetters, computer-to-plate and digital printing equipment vendors.
While the RIPs automatically perform specific sets of tasks, it has become common practice to refer to the entire process of preparing files for final output as "RIPing." This term can include not only the actual RIP function but also preflighting, trapping, screening and a whole host of other output tasks. As the entire output process has become more automated, more of these output tasks are being incorporated under the RIP umbrella.
Adobe's continuing development of PDF as the emerging standard for document exchange is central to its new RIP development. While PDF has its roots in Illustrator and PostScript, its page independence has an impact on the entire output workflow process. An advantage will be the extensibility of the Acrobat products that handle PDF files. This extensibility will allow independent vendors to develop extensions to enhance the process and even target it to specific niche markets.
To address the increasing needs of output automation, Adobe has developed two companion technologies--PDF forms and PDF Portable Job Ticket Format (PJTF). Forms allows interactive form generation, completion and form information retrieval directly through Acrobat applications and RIP implementations. In conjunction with PJTF, which allows users to predefine process order and process specifications, a very automated output workflow can be developed. Adobe's current RIP version is Level 3, which, among other things, adds native support for PDF files as well as a variety of processing efficiencies that have a positive effect on print quality and processing speed. Additionally, support for Hi-Fi color is included, which allows for more than four colors to be used. "In-RIP trapping" is yet another feature.
Adobe licenses its core technology to many vendors. As a result, various output devices may not offer all of the available Adobe RIP features and functionality. This allows more differentiation among the solutions that each of Adobe's OEM vendors offers.
Another major player in the RIP game is Harlequin. In the past, Harlequin has extended its RIP to add features and functions, such as trapping and color management, which have not been part of the standard Adobe offering of the time. Harlequin's RIP version, ScriptWorks 5.0, includes native PDF support, PostScript Level 3 language file support and preliminary support for Adobe's PJTF in the form of page setups. Harlequin expects to add increased PJTF support as it "becomes more widely implemented in the industry."
In addition to PDF, PostScript and EPS, the RIP can handle TIFF 6.0 and TIFF/IT-P1 file formats, and supports ICC color management profiles. Its Hi-Fi color capability allows for colors to be processed from virtually any color system, including CMYK, spot color systems and Hexachrome.
Unlike Adobe, Harlequin has been shipping its RIP as a "finished package." This offers equipment vendors an easier solution. It also means that most of the Harlequin-support front-ends have similar features, functions and user interfaces.
Last year, Harlequin announced a new direction that would extend its functionality even further. Through the development of EP2000, Harlequin will be creating a new approach to output workflow. EP2000 is, in effect, an "intelligent workflow controller." The goal is to create an assortment of independent workflow task processors (i.e., trapping, imposition, etc.) that can be handled by the master controller to process files in the most efficient way. Workflows then will be able to automatically adapt to the most efficient and available process stream, not necessarily a serial stream.
As printers select the "best" solution for specific needs (which include cost, process requirements, cycle times, etc.), they need to look at how a given solution will fit or enhance their process. Almost any solution can be made to work with a specific type of workflow, but some solutions are significantly better for a given type of work requirement.
Here are some examples of how specific output production tasks are handled by different vendors. In some cases, these tasks are handled as part of the RIP, while in others they are outside the RIP but part of the process solution.
Preflight. The basic preflight concept is to check and "pre-qualify" the prepared file's characteristics to ensure that they meet the requirements of the intended output process. While this can be achieved to varying degrees almost anywhere in the process, the ideal solution is handling it as early as possible. While the ideal solution is for the document's originator to use an application such as Markzware's FlightCheck of Extensis' Preflight Pro, many vendors have included an additional preflight step that occurs after the PostScript file is introduced into their solutions.
The most basic of these checks for font and picture availability, with the checking of color space and image resolution added in some cases. Some of the companies that offer this level of preflight are Agfa, Heidelberg Prepress, Rampage, Scitex and Fuji.
The next level of preflight functionality attempts to check an additional level of process conformity and even adds limited error correction specific to an output process.
Barco has developed a number of applications that handle this extended level of preflight. As a result of its original focus on packaging, Barco has created two applications that address some of the more common errors that occur in a packaging workflow. PS-Fix detects and corrects flaws such as double contours, extraneous masks, strokes as rectangles, etc. In addition, it will remove hidden objects that are part of the design.
Barco also offers Print Rule Checker, which checks a job against the requirements and setups of a specific press configuration and alerts users to non conformance. Some of these checks include register, number of ink stations and smallest printable object.
Barco also "flattens" or combines PostScript layers to reduce file size and streamline processing.
Creo has a similar process through Prescript software. This product separates multipage files into independent pages, removes redundant image data, embeds missing fonts and removes high-res image files, replacing them with OPI links.
PCC also has an operation through its PageFlow product that flattens the incoming PostScript file. The "normalization" step that is offered as part of the new Adobe Level 3 RIP also flattens and separates multipage PostScript files.
Intermediate manufacturing formats. Historically, CEPS manufacturers worked in specially designed intermediate file formats that allowed them to maximize the capabilities of their systems. When PostScript page processing entered the market, the basic workflow didn't require intermediate manufacturing file formats due to the structure of the RIP. However, to continue to offer many of the necessary workarounds for PostScripts' limitations, as well as support for existing process tools, vendors altered the standard PostScript process to have the RIP interpret the PostScript into an intermediate manufacturing file format.
At the core RIP level, Adobe doesn't create an intermediate file format--however, many of Adobe's OEM's have chosen to adapt the RIP to create one. Interestingly, Harlequin supports an intermediate file through the creation of an editable display list. However, many of their OEMs choose not to take advantage of this feature.
The approaches taken by each of the vendors that support an intermediate manufacturing format vary. Usually, if a vendor's solution uses an intermediate format, the company supports "in process" trapping, imposition and varying levels of editability. Perhaps the most widely known intermediate format is Scitex LW/CT.
Scitex recently updated its formats to add functionality. The New LW supports thousands of LW colors instead of the original 255 limit. Plus, New CT supports more color channels to allow more- than-four-color process halftones, Hexachrome, etc. Scitex supplies trapping, imposition and editing tools to be used with these intermediate formats.
PCC also uses a raster-based LW/CT format, with a complement of tools to take advantage of them. Shira also has chosen to use LW/CT but in the form of TIFF/IT.
Heidelberg Prepress uses an intermediate format called Delta List. This is a high-resolution raster file that can be color edited, trapped and imposed. Recently the firm announced that it would support PDF editing in its process through the use of the DaVinci TransMaster workstation.
Barco uses an intermediate file set called GRO. In addition to being used for trapping and imposition, GRO maintains editability in both raster and vector format until the final rasterization step just prior to output. The ability to keep the vector information editable is helpful when working with packaging files. Like Scitex, Barco's editing tools are included as part of the solution.
Agfa and Fuji have decided to build their new output workflows around PDF as an intermediate manufacturing format utilizing the Adobe Level 3 RIP core. This allows them to maintain page independence for flexibility in imposition, as well as page editability through the use of third party tools such as DigiScript from OneVision and PitStop from EnFocus.
Trapping. Trapping is a necessary part of the output process that compensates for the misregister that occurs in the printing process. Due to PostScript's limitations concerning transparent overprints, this area has received much discussion.
Until recently, any of the automated trapping solutions available were either standalone applications or integrated into a larger output workflow system such as Barco, Heidelberg, Rampage, Scitex and PCC. In 1996, Harlequin announced "In-RIP" trapping availability on its ScriptWorks (although it wasn't available in products until 1997).
This year, Adobe began offering it in its Level 3 RIP core. Agfa's Apogee incorporates this new functionality, and Fuji also has integrated this feature into its CelebraNT product, due to ship later this year.
Imposition. While imposition isn't necessarily a RIP function, it is required in many cases for final output. If you need to impose, the most important thing to consider is page independence to allow for last minute corrections and page replacement. Beyond that, consider legacy file and digitized film handling capabilities. Of course, imposition tools should be comparable to your needs.
Most vendors offering in-process imposition use either an off-the-shelf imposition package such as Imation's PressWise or ScenicSoft's Preps, although some of them have incorporated one of these packages into their solutions in a modified form. Scitex, for example, uses Preps to create the initial imposition layout, but has developed its own assembly solution to better handle page independence, legacy files and digitized film.
Process management and automation. Now that RIPs are performing more output tasks, they are moving toward adding various levels of process control and automation. As we move to a more server-oriented model, the process lends itself to increasing levels of automation. By automating and controlling as much of the process as possible, human intervention and process errors are minimized.
In a recent output workflow study sponsored by Seybold, automation was categorized into three tiers. Tier One consists of products using queues and hot folders to tie applications or process tasks together. Tier Two products add functions such as pipelining (setting up predefined process streams), job tracking and trapping, including options for setting process task parameters. Tier Three integrates process management and business management tasks to allow for a completely automated process, exclusive only of tasks that require subjective decisionmaking.
Companies that offer Tier One products include Xinet and Shira; Tier Two products include Creo, Barco, Heidelberg, Imation, Rampage and Scitex.
Currently, there are no products that achieve Tier Three levels--however many vendors aspire to that level and have supporting products on the drawing board.
As you can see, RIPs, by definition and original design, had a powerful but limited function--powerful enough to revolutionize the entire publishing process but limited to a small part of the total process. However, the industry is driving the continued development of this core technology into a more robust and complete process solution.
The marriage of an ideal workflow solution to a specific set of process requirements is ultimately the key to meeting ever-decreasing production cycle times and maximizing profitability. When evaluating a solution, try to understand the short- and long-term implications of any RIP purchase. Consider how it will be integrated into your other business functions. In addition, review this solution's impact on your long-term business strategy and ensure a smooth, positive growth toward that ideal workflow.