What format is pdf/a?

pdf/a is an ISO standard version of the PDF file format designed for long-term file preservation. The pdf/a format makes PDF files self-sustaining; PDF/A stores this self-sustainability by displaying the document's information (content, colors, fonts, images, etc.) embedded within the document itself. In other words, PDF/A files do not require any additional external information to display appropriately.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

PDF/A is an ISO standard PDF file format version used for digital information storage of electronic documents. It is based on Adobe's PDF format reference version 1.4, which is defined in the ISO standard ISO 19005-1:2005 released on October 1, 2005: A new version of PDF/A based on PDF 1.7 - ISO 32000-1 is currently in development.

Simply put, pdf/a is a type of PDF format designed for long-term file storage.

PDF/A, the full name of "PDF/Archive", is the best solution for electronic file preservation.

As the best solution for electronic file preservation, the PDF/A standard became the de facto standard in the industry. In May 2005, it was approved by the International Organization for Standardization ISO and became an international standard. As the largest authoritative standardization organization in the world today, ISO's establishment of international standards can be described as demanding. It not only requires several years of rigorous review through application, preparation, review, approval and release, but also must obtain 117 unanimous consent of all member states. This can fully demonstrate that PDF has been widely recognized as an internationally recognized standard. It is particularly worth mentioning that China, as a member state of the ISO organization, also conducted a detailed assessment and review of the PDF/A standard during this process and gave a positive evaluation.

The PDF/A standard is jointly initiated by the National Association of Printing, Publishing and Paper Processing Equipment Suppliers (NPES) and the American Association for International Image Information Management (AIIM), mainly to meet the needs of two aspects: The first is to find a way to safely preserve file contents for a long time for electronic archiving; the second is to ensure that the files have consistent display effects during future retrieval. Once this format becomes an international standard, users around the world will benefit from it. Mr. Pi Zhuoding, general manager of Adobe China, said: "The question that has existed for many years is: What file format should be used to save electronic archives? Due to the lack of recognized standards, people don't know what kind of files will appear in 50 years. Format. With PDF/A, institutions will have confidence in their work processes because they can use the PDF/A standard to create their own electronic archive access tools without having to worry about any future format issues."

PDF/A can be approved by ISO and become an ideal archiving standard mainly because it is a subset of the PDF format. Nowadays, Internet applications are everywhere, 9.2% of them use PDF format, and more than 500 million users are using the free Adobe Reader to browse files. It can be said that PDF is already the most popular file format on the Internet. Moreover, PDF has become a standard stipulated by many governments and industry associations. The Food and Agriculture Organization of the United Nations uses PDF as the standard format for publishing agricultural data. 2,400 government agencies, including the governments of the United States, Germany, the United Kingdom, and Brazil, use PDF as their electronic documents. Standard format for communication. In addition, a series of document standards based on PDF have been approved by ISO or are about to be approved. In addition to PDF/A, they also include PDF/X standards that can reliably carry out pre-press printing and high-end color advertising transmission. All this clearly shows that PDF has been widely recognized around the world as the final document sending format.

Extended knowledge: The difference between PDF/X, PDF/E and PDF/A

PDF/X, PDF/E and PDF/A standards are developed by international Defined by the Organization for Standardization (ISO).

PDF/A

In September 2005, the International Organization for Standardization (ISO) approved a new PDF/A standard for archived electronic documents. According to the ISO19005-1 standard, PDF/A is a variant of PDF. It "provides a tool that allows electronic documents to be reproduced over time in a way that preserves their appearance, regardless of the tools and systems used to create, store or produce the document."

This retention method makes PDF files self-sustaining. PDF/A stores this self-sustainability by displaying the document's information (content, colors, fonts, images, etc.) embedded within the document itself. In other words, PDF/A files do not require any additional external information to display appropriately. However, for this format to maintain its own persistence, it must exclude certain features found in standard PDF files such as film, audio, and transparency.

PDF/X

PDF/X standard is used for graphic content exchange; PDF/E standard is used for interactive exchange of engineering documents; PDF/A standard is used for electronic Long-term archiving of documents basically blocks some inappropriate functions, such as Javascript, audio, video, etc.

During the PDF conversion process, the files to be processed will be checked against specified standards. If the PDF does not comply with the selected ISO standard, you will be prompted to cancel the conversion or create a non-compliant file.

The following PDF/X formats are widely used standards in printing and publishing workflows: PDF/X-1a, PDF/X-3 and PDF/X-4(2008). The standards widely used in PDF archiving are PDF/A and PDF/A (less demanding).

PDF/X, like PDF/A, is a subset of PDF. The purpose of PDF/X is to provide designers, draftsmen, engineers, and graphic artists with an electronic file format that can be printed correctly by any service provider. PDF/X makes it possible to maintain complete consistency even if the file is processed by people in multiple locations and on different machines. This format is ideal for print-ready file transfers in most network companies; here, the sender and recipient of print-ready information are not strongly related to each other. In addition to providing a solid delivery format for printing tasks, PDF/X also offers other benefits, including a file viewer, better compression (smaller file sizes), and support for spot color process colors to identify printing conditions ( Such as which file is ready) technical means, and more. However, like PDF/A, the benefits of PDF/X also come with some compromises. For example, functions such as transparency, encryption, and JBIG2 compression are prohibited in DF/X.

Currently, the only version of PDF/E is PDF/E-1. If you want to know more about PDF/X, PDF/E and PDF/A, you can visit the ISO and AIIM websites.

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