Frequently Asked Questions about Page Description Languages

Q: What is Page Description Language?

A: A Page Description Language (PDL) is a computer language that describes the visual appearance of a printed page. It provides instructions to a printer or other output device on how to render text, graphics, and other elements on a page.

Q: What are the peculiarities of Page Description Languages?

A: The most important aspects of a PDL are:

• One file can be sent to different printers, and when the printer’s controller understands that language, it will produce a consistent, high-quality output. The PDL describes objects on the page, and the printer itself determines the best way to render them.
• Most PDLs are vector-based, so they describe elements in terms of mathematical objects rather than pixels. This allows the printer to render pages at the highest resolution without losing quality.
• PDLs are much more efficient than sending a full raster image of a page. A simple text document might be only a few kilobytes as a PDL file, while a high-resolution raster image of that same page could be many megabytes.
  
  

Q: What are the most popular Page Description Languages?

A: Here are famous examples of PDLs:

• PostScript is one of the most well-known and influential PDLs. It’s a full-fledged programming language and the foundation for many graphics and desktop publishing applications.
• PDF - the most spread one. It is a compressed and more static form of PostScript. Nowadays, it is supported by most devices and gadgets.
• PCL is the most widely used PDL in the world for laser printers. It is a simpler language than PostScript, making it more efficient for basic text-based documents.
• DVI (Device Independent)
• XPS (XML Paper Specification)
  
  

Q: What Page Description Language is the best?

A: It is a complex question because it depends on your needs. There is no single “best” PDL:

• PostScript may be the best choice for professional printing, graphic design, and publishing.
• PDF is the main choice for document exchange and archiving.
• PCL is the most common and effective option for everyday office use.
• XPS is mostly relevant in the Windows environment.
  
  

Q: How do Page Description Languages work?

A: If simple, PDLs provide a set of instructions for a printer to create a document’s final output. They do not send a massive, pixel-by-pixel image, but a compact set of commands that a printer’s internal processor reads and renders the page with the highest possible resolution.

Q: What are benefits of Postscript (PS) format?

A: PostScript has strengths in professional publishing:

• One of the biggest advantages of PostScript is its device independence, so the same file will produce the same high-quality output on any PostScript-compatible printer, regardless of the printer’s brand, model, or resolution.
• PostScript is vector-based, so it produces sharp, clean lines and smooth color transitions. Because of that any text can be scaled to any size without any loss of quality.
• PostScript provides you with the seamless Integration of text and graphics.
• It is efficient and compact.
  
  

Q: What are the drawbacks of PostScript?

A: PostScript has several significant drawbacks that make it less popular:

• PostScript lacks interactivity like hyperlinks, buttons, form fields, and multimedia because it was designed exclusively for printing.
• PostScript is complex and difficult to edit. This makes it a bad choice for general users who do not know how to code.
• While PostScript can be compact for simple vector graphics, documents with complex images or embedded fonts can lead to very large file sizes.
• PostScript doesn’t natively support modern features like transparency, advanced color management, or layered documents.
• It is not directly supported by web browsers. To view a PostScript file online, it must first be converted into a different format.
• Printing a PS document can be slower than simpler page description languages like PCL.

Q: Can AI write Postscript code?

A: Yes, AI can write PostScript code. LLMs like ChatGPT, Gemini, and others can generate PostScript code from natural language descriptions. This is possible because PostScript, as a page description language, follows a set of rules and syntax that AI models can learn and replicate. This can be useful for creating simple graphics, automating repetitive tasks, or learning the basics of the language. However, it’s not a foolproof solution.

Q: What is the difference between PS and EPS formats?

A: PS and EPS file formats are both created by Adobe and are based on the PostScript language. The main difference is their purpose: PS is designed for a complete, single-page document, while EPS - for a single graphic or illustration to be embedded within another document.

Q: What are benefits of EPS format?

A: The main benefits of Encapsulated PostScript are:

• EPS files are vector-based, which allows you to scale the image to any size without losing quality or becoming pixelated. It provides you with high-quality output on any PostScript-compatible printer.
• An EPS file can contain both vector graphics and raster images, along with text and fonts, within a single file. This makes it a more versatile format.
• The format is supported by professional graphic design and desktop publishing software, different platforms, and applications.
  
  

Q: What are the drawbacks of EPS format?

A: Before choosing the EPS format, consider its cons:

• EPS does not support interactive elements such as hyperlinks, forms, or embedded multimedia (like video or audio).
• EPS files do not support transparency, so if you have a graphic with a transparent background, you must place it on a background, which can create a box around the image when it is placed in a document.
• EPS files can be notably large if there are complex images with a large number of paths or many fonts.
• EPS allows you to embed fonts, but it doesn’t handle all modern font types well.
• EPS has no direct browser support, so to use it on the web, first convert it into a web-friendly format like SVG, PNG, or JPEG.
• The format is considered to be outdated; PDF is now the industry standard for document exchange.
  
  

Q: What are benefits of XPS format?

A: XPS (XML Paper Specification) is a file format and a page description language developed by Microsoft. Its benefits are:

• XPS is natively supported by modern Windows operating systems. This means you can manage XPS documents without any third-party software.
• Like PDF, XPS is a fixed-layout document format. This ensures that a document’s appearance remains the same on different computers and printers.
• XPS is an open XML-based standard. The format’s structure is readable and can be easily parsed by software.
• XPS supports digital signatures, for document authentication and verification.
• XPS documents can be encrypted and password-protected, which ensures security.
• XPS simplifies the printing process within Windows.
  
  

Q: What are the drawbacks of XPS format?

A: The primary drawback of the XPS format is its limited adoption outside of the Windows ecosystem. The other cons are:

• No major web browsers, like Chrome, Firefox, or Safari, natively support viewing XPS files.
• While XPS supports features like digital signatures and encryption, its overall feature set is limited.
• As a direct competitor to PDF, XPS has failed to gain significant market share. Most users and organizations are not familiar with it and prefer to work with PDF files.
  
  

Q: What is the difference between XPS and OXPS formats?

A: OXPS is a standardized version of the XPS format. First Microsoft developed XPS and then it was submitted to Ecma International for standardization. As the result OXPS format was created. It means that older versions of Windows and third-party applications may not be able to open OXPS files by themselves.

Q: What is XMP metadata?

A: XMP (Extensible Metadata Platform) makes the metadata accessible to different applications and operating systems. It was developed by Adobe and allows information about a file, such as its author, creation date, and copyright status, to be stored within the file itself in a structured, cross-platform way. The benefits are:

• Extensibility, which means you can add custom metadata to a file in addition to the standard fields, to specify details.
• XMP metadata is stored using XML (Extensible Markup Language), which provides you with a structured format.
• It is widely supported in software from Adobe (like Photoshop, Illustrator, and Premiere Pro).
• It lets you find, organize, and manage digital assets easily.
  
  

Q: Can AI generate a PS or EPS file?

A: AI can create PS and EPS files by generating the PostScript code. PostScript is a programming language, so AI models can learn its syntax and logic. You can give a natural language prompt, like “Create a PostScript file with a picture of a bird on a blue sky,” and the AI can write the corresponding code using commands like newpath, arc, and fill.

Q: Can AI generate an XPS file?

A: XPS is not a programming language but an XML-based file format. AI can generate the XML code that makes up an XPS file. This process is similar to how AI can write HTML or other XML-based languages. However, creating a functional XPS file can be more complex than generating a PostScript file, as it often involves many different XML parts and relationships.