Is pdf an image format?

Is pdf a picture format?

The pdf file is not a picture format, but a document format.

PDF, Portable Document Format (Portable Document Format) is a file format that presents documents in a way that is independent of applications, hardware, and operating systems.

The purpose of Adobe's design of the PDF file format is to support cross-platform, multimedia integrated information publishing and distribution, especially to provide support for network information distribution. To achieve this purpose, PDF has many advantages that other electronic document formats cannot compare with.

The PDF file format can encapsulate text, fonts, formats, colors, and graphics and images that are independent of device and resolution in one file. Files in this format can also contain electronic information such as hypertext links, sounds and dynamic images, support special-length files, and are highly integrated, secure and reliable.

PDF files use industry-standard compression algorithms and are generally smaller than PostScript files, making them easier to transmit and store. It is also page-independent. A PDF file contains one or more "pages" and each page can be processed independently, which is especially suitable for multi-processor systems.

In addition, a PDF file also contains the PDF format version used in the file, as well as the positioning information of some important structures in the file. It is precisely because of the various advantages of PDF files that they have gradually become the new favorite in the publishing industry.

Extension information

The PDF file format was developed in the early 1990s for sharing documents that include text formats and built-in images , can operate across platforms. Even if the computer platforms are completely different, the recipient does not need to adapt related or compatible application software interfaces.

At that time, competing cross-platform file formats with PDF also included DjVu (still under development), Envoy, Common Ground Digital Paper, Farallon Replica and Adobe's own PostScript (.ps) format.

At a time when the World Wide Web and HTML text had not yet emerged, PDF was very popular among desktop publishing workflow technologies. PDF was originally a proprietary format controlled by Adobe. It was not officially released as an open standard until July 1, 2008, and was released by the International Organization for Standardization as ISO 32000-1:2008.

Since then, control of the standard has been transferred to the ISO committee composed of volunteer industry experts. In 2008, Adobe issued a public patent license under ISO 32000-1, granting a buyout license for the patents required to make, use, sell, and distribute PDF-compatible applications.

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