Prepress "engine" - RIP

For many printers, digital prepress technology is still a mystery, especially the RIP processor. In addition to RIP, we also always hear about the printer's built-in control unit. In fact, RIP is essentially the same as the built-in control unit, but it is also different. It sounds like there is something mysterious, let's uncover the mystery of RIP.

course

Without the built-in control units of the RIP and the printer, the printing industry has long since passed its end. The integration of data files, pictures, and colors will be meaningless. Variable information printing, or personalized publishing, is just a concept. The RIP processor is at the heart of any digital prepress system. The RIP processor can output pixels to film or plate, paper or display. Previously, the RIP was just an attachment to the output device. On each typewriter, there was a black box, convertible bytes, etc. that were displayed on the screen. With the development of the Postscript language, everything has changed, and RIP has evolved into an indispensable technology for any output program.

Postscript is a page description language, its invention, began the desktop publishing revolution. By 1985 Apple introduced a laser printer, the first Postscript printing device with a built-in control unit. In other words, the task of this RIP prototype is to interpret the Postscript language code from Apple Computer, form an outlet with an output resolution of 300 dpi, and output it to the printer. In the same year, Linotype launched the Linotype300 typewriter, rewriting the history of the picture and text that cannot be changed. A powerful negative description language, and techniques that can explain this language, can convert images into dots, meaning that an identical file can be output on the output devices of two different companies, and thus a graphic Phototypesetting machine.

With the development of Postscript, RIP technology is no longer built into the output devices they drive. The role of RIP is not only a bridge between front-end and back-end devices. However, PostscriptRIP also encountered many new problems. Although these issues, most of the Postscript language and hardware upgrades have been resolved. Different PostscriptRIPs have different interpretation methods and they do not generate the same output. Of course, the file output by RIP mainly depends on the content of the file.

The most basic form of RIP or built-in control technology is to convert the dot on the computer screen into a dot form on the printer. If the pictures are all 72dpi, the control unit needs to tell the printer whether to print the dot at a certain point or not. However, if the output device is output at 300 dpi, the control technology will have to convert the 72 dpi screen resolution to 300 dpi while ensuring that the font is perfectly colored without jaggies. This process does not sound like many flowers, but it requires very clever and complicated procedures.

Postscript and RIP technology have indeed caused a revolution in the printing industry. This twin brother has penetrated every corner of the printing industry. In general, we can find a built-in control unit on the printer in the office. Most of them are defined as Postscript compatible devices. Deeper, we have RIP systems for color copiers, such as Imagings (EFI) Fiery Electronics and Splash's RIP.

Each RIP has its drawbacks: SplashRIP and Xerox are designed for each. FieryRIP cannot drive multiple output devices. However, Colorbus RIP can use the same RIP to drive two color copiers and large format inkjet printers.

method

In the printing field, RIP technology has become the core of the digital workflow. The RIP interpretation method can be divided into two kinds: NORM method and ROOM method.

(1) NORM--NormaliseOnceRenderMany (interpreted once, colored multiple times). Refers to all the data described in the Postscript language command in the file, all explained first, then one page per page. Far-end methods can be used to interpret documents in PDF or other formats and can lay the foundation for future operations (such as defining trapping, OPI, imposition, etc.). Agfa, an advocate of this approach, has launched a version of Adobe Normaliser technology that can generate PDF files for Agfa's Apogee digital workflow.

The methods used by Harlequim and BarcoGraphics are somewhat different from the NORM method. After their graphic data have been interpreted, they are not immediately colored. For example, Harlequin RIP generates an interpreted file that can then be added to other modules (such as trapping, color management, etc.). The best application of this technology is the NewAgeRIP from Purup-Eslofot, which drives their imagesetters and platesetters.

(2) ROOM--RenderOnceOutMany (coloring once, output multiple times) was first proposed by Scitex. Refers to all the data described in the Postscript language command in the file, which is fully interpreted and colored first, and a page is output one page at a time. Delta is also a method used by Heidelberger DeltaRIP to interpret the documents and generate a small scale continuous shrink raster file. The main advantage of ROOM is that the output consistency is guaranteed on different output devices because the file has already been colored.

However, because the ROOM method uses interpreted and colored files (although they have not yet been screened), the files are large and are not conducive to network transmission. Moreover, it is necessary to shrink data when proofing, and it is difficult to maintain data consistency. Although the implementation of RIP is somewhat different, everyone believes that RIP should also have the following features, such as imposition with work tickets, OPI (a low-resolution image when displaying, and a high-resolution image when output) Trapping and so on.

The founder of EFI, Mr. Efi Arazi, also founded Scitex. When asked about the difference between Scitex and EFI, his words also answered the differences between professional RIPs. He taxed, "When you have a runny nose, rubbing it with a precious Irish handkerchief, it's great to learn because it's soft; it's easier to rub it with a regular facial tissue. The effect is the same. Most people use facial tissue."

In many RIP technologies, you will eventually find a special one of this.