Quick Guide: Raster vs Vector Images

Previously, we’ve discussed file types and resolution. Both of these come into play when we’re discussing the difference between raster images and vector images.

Raster Images

A raster image is one that is static, meaning that it is drawn at a precise size and made up of a specific unit, like pixels. Technically speaking, a raster image uses a bitmap to store information. As we discussed in resolution, it’s easy to scale down a raster image because it require less information. But enlarging a raster image can create a pixelated effect because there is not enough information to make the image larger and fill in the gaps.

Common file extensions for raster images include .JPG, .GIF, .TIF, and .BMP. You can create raster images in many programs, but Adobe Photoshop is the most robust.

Vector Images

A vector image is one built on a series of mathematical statements, which means that it can be redrawn at any size and still have smooth edges. Instead of having a bitmap that specifies exact locations of each pixel, a vector image is saved as a sequence of vector statements that describes series of points to be connected.

Common file extensions for vector images include .AI, .EPS, and .SVG. Vector images are easily created in Adobe Illustrator.

Can You Convert Between the Two?

Short answer: yes, you can. It’s easy to rasterize a vector image because a bitmap can be drawn at the exact size of the current image. In a way, this locks down the image because it can no longer be enlarged without consequences.

It’s harder to vectorize a raster image. This involves tracing or redrawing the image in the mathematical language. An exact redrawing is not typically possible, so vectorized images are not always of good visual quality.

Need more information? Contact your Sales Consultant and we can put you in touch with our graphics specialists in the Prepress Department!