Differences between vector and bitmap images

There are different types of images, digital and physical ones, but have you ever wondered how they are created? Digital images can be classified into two categories that are created in different ways: bitmap or vector image. At PCG, we help you understand the differences between them and choose the most suitable one for your designs.

Digital images are composed of bits, which in computer language means the minimum unit of information composed of binary digits (0 and 1).

When we are creating a design which is composed of images, we have to choose between vector or bitmaps image. These two types are created and edited from different applications, therefore, it is necessary to understand  the differences, the advantages and drawbacks of each one.

Bitmap

This is the most commonly used type of image. The most common formats are jpg and png. They are composed of many pixels. A pixel is a square of color and the union of several pixels forms a complete image. Each pixel is a bitmap that can be of a different color and brightness, however all pixels have the same size. The number of pixels of an image is determined when the image is created. Whether it is created from a digital camera (or a mobile phone) or editing programs (Photoshop for example), you can choose the resolution (pixels per centimeter) and the amount of pixels the image will have, in height and width. The higher the number of pixels, the higher the resolution and the more details you will see. If you see the full image, those pixels should be invisible, but if you zoom, you will see the pixel squares and their color. One of the disadvantages of bitmap is its sensitivity to size changes, especially enlargement.

Vector image

Like bitmaps, a vector image is also formed by the union of basic units of information, no longer in the form of pixels but in the form of mathematical vectors. Mathematical vectors are a set of points and information about how these points are connected. Vector images require far less information to define an image and therefore they weight much less. Their biggest disadvantage is that they are defined by straight or curved lines and cannot be used to represent realistic photographs or images because it is impossible to define their details. Their main advantage is that they allow resizing, they are the best option for the design of logos, posters, corporate image, etc. The most common formats are eps, ai (Adobe Illustrator) or pdf.

In short, to create a photographic image it will be more convenient to use bitmap, as long as you’re aware of its limitations and if you want to make large format products is better to use vectorized images that can be enlarged or bitmaps with good resolution.