RIP (Raster Image Processor), Raster Image Processor. The role of color desktop publishing systems and large-format print output is very important. It is related to the quality and speed of output, and can be said to be the core of color desktop publishing systems or large format output. The main role of RIP is to interpret various images, graphics, and texts in a computer's production layout into dot matrix information that can be recorded by a printer or an image-setter, and then control a printer or an imagesetter to record image dot matrix information on paper or film.
RIP is usually divided into two kinds of hardware RIP and software RIP, there are also RIP soft and hard. The hardware RIP is actually a dedicated computer dedicated to interpreting the information on the page. Because the amount of computation for page interpretation and screening is very large, hardware RIP is often used to increase the speed of operation. Software RIP uses software to perform page calculations, and the interpreted information is transmitted to the output device through a specific interface card. Therefore, the software RIP is installed on a computer. At present, the computational speed of computers has been significantly improved. RIP's interpretation algorithm and screening algorithm have also been continuously improved, so the interpretation speed of software RIP no longer lags behind hardware RIP, and even exceeds hardware RIP. In addition, software RIP is easy to upgrade and can be increased with the increase of computing speed of computers. Therefore, it is increasingly welcomed by users.
RIP is also the key to directly reflecting the openness of the system. Therefore, whether RIP conforms to the Postscript standard is related to whether it can explain the PS files generated by various application software, whether it can support Chinese characters, and whether it supports various hardware platforms. Image screening is also performed by RIP during the output process. There are many different algorithms for screening. Each RIP manufacturer has its own screening algorithm, such as HQS of Lianhe. Haier (now Heidelberg). Plus, Agfa's Balanced Screening, Adobe's Accurate Screening, and more. However, different algorithms will produce different effects, and the speed of screening will vary greatly. The shape of generated rose spots will also be different. This is mainly due to the slight differences between screen lines, screen angles, and dot shapes. To be accurate in screen angle, the number of screen lines is close to the nominal value, which usually takes a large computational cost, and the interpretation speed is reduced accordingly. Therefore, the RIP's screening algorithm directly affects the quality of the image and the output speed.
The working mode of hardware RIP is generally relatively simple. Usually, network printing is used, and no preview function is available. The software RIP receives page data more flexibly, and can have network printing mode. It can also directly explain the PS formed by the groupware. ) The file can also be interpreted in batch mode to PS files.
The so-called network printing mode refers to setting up RIP as a network printer. Each workstation can be connected according to the method of selecting a network printer. The data printed by the groupware software is sent to the RIP for interpretation via the network, and then sent to the output device for output. This method is the easiest and most convenient output method. As long as it is connected to a workstation on the network, it can be printed directly. The disadvantage of this output method is that it takes a long time to occupy the workstation, but you can use the background printing method to speed up the offline speed.
Explaining PS files is a little more complicated. First, use the groupware to print the layout into a PS file, transfer it to the RIP through the network, or place the PS file in a batch folder. Finally, the RIP opens the PS file to explain the output. Many software RIPs use this output method, especially early software RIP. The network printing function is very weak and can only be output in this way.
The batch output method is to print all the files to be output into PS files, and put them in the same folder, which will be automatically output by RIP. This method is more suitable for the job when the same processing conditions, but this method can not preview the output, so make sure there is no problem in the layout.
The function of RIP is constantly being strengthened, such as the processing of large version, large version proofing, last minute modification, preview, pre-checking, rasterization, imaging, etc., which are now included in the RIP. Some RIPs also involve post-press binding, and a few RIPs can also send some print data related to dots and inks to output devices. Because the speed of RIP can not keep up with the processing speed of the image output machine, Multi-RIP has emerged, which is used for multiple RIP parallel operations. Now that RIP is used to handle more output tasks, RIP becomes a pivotal, intelligent service center that performs various output functions.
The main technical indicators of RIP
Postscript compatibility. Because the Postscript page description language has become the common language in the printing industry and the image output industry, all kinds of desktop application software use this as the standard. Therefore, the compatibility is directly related to whether RIP can explain the layout of various software productions. Whether there will be mistakes in the.
Explain the speed. Explaining speed is one of the issues that users are most concerned about because it is directly related to the efficiency of production. However, the overall speed of the output also depends on the recording speed of the imagesetter and the network transmission speed, so it is better to comprehensively examine the speed of the system.
· Screen quality. Adding network is an important function of RIP. The quality of screening directly affects the quality of printed matter and is very important in the production of color prints. Some prints are thick on the Internet at some color levels, have poor visual effects, and are not obvious at other levels. This is caused by the RIP screening algorithm. The quality of screening and the speed of interpretation are a contradiction. The computational complexity of the fine screening algorithm increases a lot, and the speed decreases greatly.
· Chinese character support. Supporting Chinese characters is a necessary condition for our country. The current RIP is no problem, but some old systems may still have such RIP.
· Operation interface and function. The functions of various RIPs are different, and there may be some differences.
· Support network printing function, can make use very convenient, more importantly, can be used between different hardware platforms, which is now often referred to as cross-platform system.
• The preview function can be used to check the layout of the post-explained layout to avoid errors and reduce waste. Therefore, in most cases, the preview must be checked and the preview function becomes an indispensable function.
· Imposition output function, can use the output media more effectively, improve work efficiency. Because the width of the stacking paper of the imagesetter film and large format output is fixed, and the layout of the output is ever-changing, it is often encountered that a very small medium is used to output a very small layout, especially a large-format image-setter. It is easier to encounter this situation, resulting in the waste of film, and using RIP with imposition output function can solve this problem.