Raster File Types — Everything You Need To Know (and a bit more)

Updated Jun 15, 2018
Raster file types - everything you need to know

At some point, all of us have laughed at a hilarious animated GIF or shared a beautiful JPEG photo. These are just a couple of examples of raster file types. Everyone who uses a laptop, tablet, cellphone or digital camera will come into contact with raster graphics on a daily basis—but how much do you really know about them? This article and infographic will give you a handy rundown of some of the most common raster file types, their pros and cons, and their specific uses. 

Infographic on raster file types

Table of Contents

Common features of raster images

Whilst all raster image formats are different, there are a few basic features which all of them share.

raster image example of letter 's'Raster graphics are one of the two most common methods used to display images, and can be contrasted with vector graphics. When you take a photo with a digital camera, scan an image using your scanner, or view most computer graphics, then you’re dealing with raster graphics. Paper patterns used by many industries as prototypes are mostly in raster format as well. 

A raster image is essentially a rectangular grid. Within this grid lie thousands of tiny individual squares of color, known as pixels. Together, these pixels form the image that you see on screen. However, each pixel acts independently from all the pixels around it. So, when you zoom into a raster image, you’re not making the image bigger—you’re actually making each individual pixel within the image bigger. As a result, zooming into or scaling a raster image can leave it looking blurry and undefined. Raster images are only intended to be viewed at a particular size, and lose quality when scaled up or down. This is known as resolution dependency.

Related: Extra Terms
        • Pixels is short for Picture Elements. A pixel is, quite simply, a small block of color. A raster image is made up of many different pixels displayed on a rectangular grid.
        • PPI/DPI stands for Pixels or Dots Per Inch. This term refers to how many pixels are displayed within a certain physical space. For example, if a 100×100 pixel image were displayed within a 1 cm square, it would have a resolution of 100 pixels per centimeter. This measurement is particularly important when printing a raster image, as it determines the quality of the printed image. Roughly speaking, the higher the PPI/DPI, the better the quality. You can make use of programs like Photoshop to alter an image’s PPI to increase quality.
        • Resolution dependency refers to the fact that raster images are intended to be viewed at a particular scale. When they are displayed at the wrong scale, they can lose definition and appear jagged and blurry.
        • Compression refers to the use of different techniques to reduce the file size of a raster image. This is an important process, because an uncompressed raster image can have a very large file size. This is because a raster image contains information regarding each of its individual pixels. Images can either be compressed using lossy or lossless compression.
          • Images compressed using lossy compression are typically very small in file size. However, using this compression method causes an image to lose quality over time. 
          • Lossless compression is a method which allows a raster to be compressed whilst maintaining its quality. An image compressed in this way will be smaller than an uncompressed raster image, but will likely be larger than an image compressed using lossy compression.

Check out our glossary for the definitions of any other technical terms you may come across while using Scan2CAD.

Overall evaluation of raster images


plus-sign  Raster images faithfully display the color information of an image, making them a great choice to display detailed images

plus-sign  They’re widely supported by web browsers, which makes them easy to share

plus-sign  They can be opened using practically any image editing software


minus-sign  Scaling a raster image can dramatically affect its quality

minus-sign  There is no way to pick out and edit an individual element within a raster image—any changes you make will affect the image as a whole

minus-sign  Uncompressed raster images are large in file size—and even when compressed, they’re often still larger than equivalent vector graphics

minus-sign  Their detail can make them an unsuitable choice for certain applications, such as for logos

Raster File Types

Everything you need to know - JPG files


The JPEG format is named for the organization which created it, the Joint Photographics Expert Group. This is an extremely common format, and is typically used for sharing photographs. Its small size means that digital cameras are able to store large numbers of photos with a small amount of memory.

Our ultimate guides will teach you everything you need to know about JPEG to DWG conversion—or, click here to find out how to convert from JPEG to DXF.


plus-sign  JPEG uses 24-bit color depth, which means that a JPEG image can contain more than 16 million colors!

plus-sign  Since JPEGs are typically small in size, they take up little memory on a PC or digital camera, and can easily be shared via email.

plus-sign  JPEGs are widely supported by web browsers.


minus-sign  Unlike GIF, JPEG only supports still images—no support for animation
minus-sign  JPEG images are compressed with lossy compression, which means they lose quality when edited

minus-sign  The format doesn’t support transparency

Everything you need to know - JPG files2

JPEG 2000

JPEG 2000 was created to improve upon the existing JPEG format. Whilst the original JPEG format caused images to lose quality when compressed, JPEG 2000 was designed to combat some of this loss in quality. It uses a wavelet-based method to compress images, with the goal of storing higher quality images within a small file size. Despite these advances, JPEG 2000 has not become a widely-used format.


plus-sign  JPEG 2000 improves upon JPEG by reducing the perceptibility of compression artifacts

plus-sign  It supports both lossy and lossless compression

plus-sign  More flexible file format


minus-sign  Despite its advantages over JPEG, it has remained an uncommon format

minus-sign  It is not widely supported by web browsers

minus-sign  In certain cases, JPEG 2000 can still be less efficient than other formats, such as PNG

Everything you need to know - GIF files


One of the most common image formats on the web, GIFs (Graphics Interface Format) are typically used for web graphics. Unlike many other formats, GIF also supports animated images. The popularity of animated GIFs is such that GIF has become one of the most widely-recognized file formats around—and for many people, “GIF” is synonymous with “animated GIF”. To learn about GIF to DXF conversion, click here

"I'm gonna need a GIF of that"


plus-sign  Its support for animation has made it incredibly popular
plus-sign  It is widely supported by web browsers
plus-sign  Uses lossless compression


minus-sign  A GIF file can store only 256 colors

minus-sign  Despite their lossless compression, GIFs are often of low resolution 

minus-sign  In most cases, GIFs have larger file sizes than equivalent JPEG or PNG files

Everything you need to know - PNG files


PNG is the most used lossless image format on the internet. The format was created to improve upon the existing GIF format. There were clear deficiencies with GIF, but as it was patented, there was no way for external programmers to improve upon it. The idea thus came about for a replacement format: PING, to stand for PNG INot GIF. At the time, only 3-letter file extensions were available, so PING became PNG. Nowadays, PNG officially stands for Portable Network Graphics.


plus-sign PNG supports different color depths, from 8-bit color (256 colors) through to “true color” (24 bits, over 16m colors)

plus-sign Uses lossless compression

plus-sign  Uses more advanced transparency than GIF

plus-sign  Supported by current web browsers

plus-sign  Better format for high-quality images than JPEG or GIF


minus-sign  Not supported by some older browsers (such as IE6)

minus-sign  The higher quality results in larger file sizes

Everything you need to know - BMP files


Bitmap is one of the simplest file formats in raster graphics. Whilst other raster formats are more complex, a bitmap (or BMP) file simply contains information about each individual pixel in the file. In the past, BMP files were uncompressed, leading to huge file sizes. Now, it’s possible to compress BMP files using lossless compression, though uncompressed bitmaps are still available.

Because of its simplicity, virtually every device imaginable supports BMP files. However, its huge file size means that in most circumstances, BMP is one to avoid. If, however, you still need to convert using this file format, find out more about how to use Scan2CAD to convert BMP to DXF.


plus-sign  BMP supports true color images (24-bit color depth, more than 16m colors)

plus-sign  Lossless compression is now available for BMP files

plus-sign  Supported by practically every device


minus-sign  BMP files are typically very large in size

minus-sign  Usually do not scale well

Everything you need to know - TIFF files


TIFF (or TIF) is a commonly-used file format in the fields of printing, graphic design, and photography. TIFF stands for Tagged Image File Format, as TIFF files also include tags containing additional information about the image. It uses lossless compression, and is useful for storing high-quality images.

Due to its high quality, it is a good file format to choose if you want to vectorize your raster image. In fact, Scan2CAD recommends saving your image files as TIFF before converting to DWG or DXF in order to increase your chances of optimal vectorization results.


plus-sign  TIFF supports high-quality images

plus-sign  Uses lossless compression

plus-sign  Supports true-color images

plus-sign  Recommended for vectorization


minus-sign  Not widely supported by web browsers

minus-sign  Some programs are unable to open compressed TIFF files
minus-sign  Typically very large in file size—a single TIFF file can take up 100 MB of storage space

minus-sign  Often too large to send via email

Everything you need to know - PCX files


One of the first widely accepted image formats, PCX (Picture Exchange) was created in 1985 to serve as the native file format of the PC Paintbrush software. In the proceeding decades, however, newer formats (such as JPEG, PNG, and GIF) have superseded PCX, and it is no longer a common format.


plus-sign  Good image quality

plus-sign  Extended to support true color images


minus-sign  Older versions only support 8-bit color depth

minus-sign  File sizes can be large

minus-sign  Surpassed by more modern formats

Which raster file type should I use?

Image Conversion - Pixelated raster to vector With so many file types available, it can be difficult to know what to choose—especially since each file type fulfils a similar purpose. However, there are subtle (and less subtle) differences between the formats which mean that each of them has specific uses. JPEGs, for example, are a great format for storing and sharing photos. The lossless nature of PNG images makes them a good choice for web graphics. GIF, meanwhile, is a perfect choice for sharing animated images.

If you’re here on the Scan2CAD blog, though, you’re probably interested in knowing which format is the best to choose for converting from raster to vector. We recommend saving your raster images in TIFF format due to their lossless compression and support for high-qualitytrue color images. Their file size may be a concern for certain applications, but for vectorization purposes, the good image quality offered by TIFF is crucial.

Whilst this list covers some of the most commonly-used raster formats, it is not exhaustive. There are hundreds of different file types available—check out which raster (and vector) file types are supported by Scan2CAD.

Interested in converting from raster to vector? Try out Scan2CAD’s free 14-day trial today and make the most of its vectorization tools, OCR capabilities, and editing suite

scan2cad advert for free trial