Image files can be either raster or vector formats. Raster formats like JPEG and PNG store images as a grid of pixels and may lose quality with editing, while vector formats like SVG use mathematical equations to describe images and can be resized without quality loss. Common raster formats are JPEG, PNG, GIF and BMP, which are best for photos, while vector formats like PDF, AI and SVG are preferred for print quality graphics. Both raster and vector formats have advantages depending on the image type and intended use.

1. Image File Formats
BY: NORWOOD EVERETT A. DADULO, KARL MICHAEL S. RUBIN

2. Image File Formats
•Are means of storing and organizing
digital images, photos and illustrations
•Classified into two types; raster image
files and vector image files

3. Raster Image Files
• Raster Image/bitmap –means of representing digital
images in bits of information for storage, which
translates into pixels when viewed on the screen.
• Most of the raster files are lossy.
• It is the common format you will encounter in the
Internet and with many digital image files, such as
those from digital cameras.
• Stored in bit maps. Examples of this type are the
JPEG, GIF, and PNG files.

4. Pixel
• The word pixel comes from the words picture (pix)
and element (el).
• Is the smallest information of an image.
• Images using pixels are usually represented in dots
or squares that are arranged and added together to
form the picture.

5. TYPES OF RASTER IMAGE FORMATS

6. Bitmap Image (.bmp)
• An image file format developed and used on Microsoft
Windows environment and is stored in a graphic file
format called device-independent bitmap (DIB)
• Has a file extension of .bmp or .dib
• Not a common format on the World Wide Web because of
its large file size.

7. Graphical Interchange Format (.gif)
• An image file format that is very popular on the
World Wide Web because of its portability (small file
size) and support for animation.
• It is ideal for images with large areas of uniform
color, small images, images with text, navigation
buttons but it is not good to use for photographic
images.
• It supports only a small 8-bits per pixel color
scheme.

8. JPEG Image (.jpg)
• Standardized by the Joint Photographic Experts Group
(JPEG) is a common method for photographic images as
well as transmission of photos on the World Wide Web
since it supports 24-bits per pixel color scheme.
• Many digital camera store photographs in JPEG format.
JPEG is not ideal for use on line art.

9. Portable Network Graphic (PNG)
• A free, open-source bitmap image format made to
improve on GIF which has small file but can handle
more color since it supports 24-bit per pixel color
scheme and supports true color (16 million colors).
• Does not support animation.
• Employs a lossless compression, meaning it does not
loose the quality of the image despite successive
editing.

10. Photoshop Document (PSD)
• A native file format for Adobe Photoshop, and since
many are using this program to create images
• Photoshop has the ability to read all of the above
formats and edit them
• It is very popular

11. Vector Image/ Vector Graphic Files
• Vector images are lossless files created using mathematical
geometric equations to represent images in digital computer
graphics.
• Has the advantage of retaining its quality at any desired image
size, unlike raster images that appear pixilated when displayed in
expanded image sizes.
• It is preferred format for those who desire quality prints and
display images.
• Examples of this type of format are: PDF, Encapsulated Postscript,
Scalable Vector Graphics, and Windows Metafile.

12. TYPES OF VECTOR IMAGE FORMATS

13. Adobe Illustrator (.ai)
•Adobe Illustrator File is the extension for
graphics created using Adobe Illustrator
which is created using paths and lines
connected by points instead of bitmaps,
which may include objects, color, and text.

14. Drawing File (.drw)
• Drawing File is generic drawing created and stored
in vector format that uses lines or paths to represent
images.
• These images are output of the following programs,
Apple Appleworks, Microsoft Picture It,
CorelDRAW and Corel Paint Shop Pro.

15. Drawing Exchange Format (.dxf)
• A drawing format developed and introduced by
Autodesk the maker of AutoCAD and is used for
computer-aided design (CAD) vector images.
• This format is similar to .drw file but is universal so that
AutoCAD can be opened using other programs such as
Vectorworks, ArchiCAD, Corel Draw, and other CAD
programs.

16. PostScript (.ps)
• Is a page description language (PDL) developed by
Adobe, basically a language for printing documents
on laser printers and image settlers (high resolution
printers)used to produce camera ready copies.
• Whether images or fonts can be changed in size
without image quality reduction or pixilation and
can be printed on a PostScript printer even without
an open program.

17. Scalable Vector Graphic (SVG) (.svg)
• Is the most common vector graphic format on
the internet; it was developed by The World
Wide Web Consortium (W3C) to display vector
graphics.
• SVG is an open format and can be opened by
Adobe, Core and open graphics programs.

18. •Other File Formats include TIFF
(Tagged Image File Format), RAW (Raw
Image Format), GIF (Graphics
Interchange Format), and the PSD
(Photoshop Document