Printing is the technology of transferring the text and text information on the original manuscript to the printing object through plate making, plate printing or other ways. To achieve this process, you need to have plate, manuscript, substrate, ink, printing equipment. It can be said that he is a comprehensive science and technology, which mainly studies the basic theory of Printing Science, printing graphic information processing, printing technology, various recording plate making materials, printing materials and their application. The graphic information on the original manuscript is completed by typesetting, design, production and output. It is also an important part of prepress technology.

Before printing, it mainly includes production, output and printing. The process of production and output is as follows: sales staff of printing company send manuscripts, internal customer specialists arrange design and production, film output proofreading. In this process, inspection is an important link in the printing work for printing companies. The professional term of inspection in plate making is called proofreading. It mainly includes six aspects (1) text (2) image (3) dot (4) appearance (5) logo (6) others. Only according to the inspection, can we ensure the correctness of the film, of course, the most important thing is to rely on the careful proofreading staff.

The specific operation of pre printing workflow can be roughly divided into seven processes:

1、 First of all, we should understand the customer's design and printing requirements, and accept customer information;

2、 Design: including input text, image, creativity, composition, production;

3、 Color proofreading or black-and-white proofreading for customers to modify;

4、 Revise according to the proofread;

5、 Proofread the draft again and let the customer revise it until it is finalized;

6、 Let customers sign and proofing film;

7、 Send to the printing proofing, let the customer check whether there is any problem, if no problem, let the customer sign. The pre press design is complete. If there is a problem in proofing, you have to modify and re output film.

There are three points for attention in the design of computer system

1、 According to the final size of the original image scanning or electronic distribution, in the image software to adjust the image, at the same time can complete some creative design work.

2、 In the graphic or typesetting software for typesetting design work: including input text, drawing graphics, placing images.

3、 After the client has finalized the document, it will be sent to the output center for film output. The laser Imagesetter works in postscript language. The layout is described as a dot matrix image by Rip (raster image processor), and divided into four color slices: C (cyan), m (magenta), y (yellow), and K (black). If the final requirement of the design is not to output film, but to large-scale color inkjet printing samples, then the output requirements of inkjet printer can be followed.

There are many kinds of image file formats before printing, and the file properties are also different. The file format determines what type of information should be stored in the file, how the file is compatible with various application software, and how the file exchanges data with other files. Because there are many formats of images, we should decide what format the images should be stored according to the purpose of the images.