An overview of vector image file formats
Image by kiyanochka.
PDF file format
PDF (Portable Document Format) can contain vector images, and widely used in printing and for displaying documents and presentations; the format is made in accordance with the ISO 32000 standard. In addition to vector images it can also contain raster ones, fonts and media, along with PostScript elements. Some printing devices even support this format on the hardware level.
- The document appears the same no matter where it is opened
- The software for displaying PDF-document content is free
- Widely supported by printing hardware
- File contents may be compressed to save up disk space
- Digital signatures provide different levels of security
- The only con to be listed is the possibility to edit the files, which usually requires special software. The new PDF documents are frequently created in other software, which then saves/converts the data into PDF format (sometimes even emulating printing process through a virtual device).
Common software: Foxit Reader, STDU Viewer, Adobe Acrobat Reader
Ai file format
Closed type format used mostly by Adobe Illustrator. A typical file contains data about points and lines, can contain fonts and colours; the PostScript language is widely used in the file. Frequently utilized for logos and advertising.
- Provides a good image quality on changing the scale of its elements
- A stable and widely recognized format
- Files made not by Adobe Illustrator itself end up being of huge size
- Ai files made by newer Illustrator versions cannot be opened by older programs
- Upon conversion from Ai to some other format, some effects may become lost
Common software: Adobe Illustrator, CorelDRAW Graphics Suite, ACD Systems Canvas
Cdr file format
Cdr - is CorelDRAW closed project format. The file usually contains vector objects and text; and it can have multiple pages. Used mostly in printing for advertising and business cards.
- Able to store object's special effects and parameters; mostly popular due to the popularity of CorelDRAW
- The images created in newer versions have bad reverse compatibility, i. e. cannot be opened (or opened with errors) by earlier versions of program suite
- Very bad compatibility; converting the file usually results in display errors and distortion
Cmx file format
Cmx - unificated Corel format with metadata; in use since sixth version, stores images with parameters and data compatible with other Corel applications. Same as Cdr, mostly used in printing, compatible with PostScript formats and as such, cannot contain shadows, transparency etc.
- Unlike Cdr, can store layer data when imported
- If an image of some other format cannot be printed on a certain hardware, usually Cmx conversion helps, although some image properties may become lost in the process
- Compared to Cdr, Cmx contains only one page
- When converted into other format, the image may lose some of its data
Common software: all CorelDRAW versions, Adobe Illustrator version 6 through 8, ACD Systems Canvas 15
Eps file format
Eps - is an old graphic format, predecessor to Ai. Can contain not only vector, but also raster objects; developed to a simplified PostScripr format. Can store data in binary as well as in text form (ASCII table). Files also contain data about the image size and a preview icon.
- Easy to manage especially if you need a lot of files printed on a PostScript-supporting hardware
- Changing width or height of the image does not negatively impact its quality
- Thanks to its amazing compatibility, can be used for file conversions
- Does not support multiple pages
- Can't have transparency effects
- Relatively large file size
Svg file format
Svg (Scalable Vector Graphics) is a 2D format for images in XML language. Can contain images, text and simple geometrical figures, in its own - a text file with a set of commands and operators in SVG language, where the image is created from a number of simple lines geometrical figures. The SVG format does not have a compression scheme of its own, but due to the textual nature of XML, an SVG graphic can be compressed using a program such as gzip. Using such images reduces the network load on servers, thus increasing the load times of web pages.
- Perfect scalability
- The effect scripts and styles (transparency etc.) can be applied easily in a text editor
- Files contain, in addition to image, the necessary XML data, which can under certain circumstances take quite a lot of disk space
Common software: can be displayed using any browser; corrections can be made using CorelDRAW or Adobe Illustrator, or even using basic text editors with enough knowledge of SVG language.
Swf file format
Swf - is not solely a vector image format, it can contain even media materials (e. g. video). Developed for use with the Flash system (Macromedia, later Adobe); for its time it gained wide popularity for advertising, animated logos and games.
- Small size for video
- Good scalability
- Can't add some special effects (e. g. transparency)
- Vector images may become rasterized during conversion, colours may change as well
Common software: Adobe Flash Professional
Wmf file format
Wmf (Windows Metafile Format) - is both a vector and raster image format, common to Windows operating system, originally designed way back in 1990. Essentially, a WMF file stores a list of function calls that have to be issued to the Windows Graphics Device Interface (GDI) layer to display an image on screen. Since some GDI functions accept pointers to callback functions for error handling, a WMF file may erroneously include executable code.
- Limited number of usable effects
- Low quality of large images