Difference between a raster image and a vector image?

Created on 28 April, 2023 | FAQ |   | 2 minutes read

Raster graphics and vector graphics are two different types of graphics file formats used to display images on digital media. They have different properties and applications, which is mainly due to the way they store and display images. Below are the main differences between raster and vector graphics:

Image structure:

• Raster images (also known as bitmap images) are made up of pixels, which are small squares that each contain a color. A raster image is a rectangular grid of pixels that make up an image.
• Vector graphics are composed of mathematical formulas that describe paths and shapes. These paths consist of points, lines, curves and shapes defined by their geometric characteristics.

Scalability:

• Raster images lose quality when scaled (enlarged or reduced). This is because the number of pixels is fixed and scaling the image stretches or compresses the pixels, resulting in a blurred or grainy image.
• Vector graphics are scalable without loss of quality. Because they are based on mathematical formulas, they can be recalculated and displayed at any size without loss of sharpness or clarity.

File size:

• Raster images usually have larger file sizes than vector images because they need to store information about each pixel in the image.
• Vector graphics have smaller file sizes because they only need to store the mathematical formulas needed to generate the image.

Applications:

• Grid images are suitable for photographs and complex images with many color gradations, shadows and textures, where each pixel is important to the overall display.
• Vector graphics are ideal for logos, illustrations, icons, typography and other graphic elements that require frequent scaling or where sharp lines and clear shapes are essential.

Many common file formats:

• Raster images: JPEG, PNG, GIF, BMP, TIFF
• Vector graphics: SVG, EPS, AI, PDF (sometimes), DXF

In general, raster images are better for photographs and complex images, while vector images are better suited for graphic designs, logos and illustrations that often need to be scaled or resized.

Creating QR codes in vector files or raster files

When using QR codes in conjunction with images, it is important to consider which type of image (raster or vector) is best suited for your purposes. In the case of QR codes, vector graphics are usually the better choice for the following reasons:

1. Scalability: Vector graphics can be scaled without loss of quality. This is important when creating QR codes because they often need to be printed on different sizes and media. With a vector image, you can be sure that your QR code will always be sharp and clear, regardless of size.
2. Error Correction: Although QR codes incorporate error correction to enable data recovery when damaged, it is still important to have a clear and sharp QR code. Vector graphics guarantee sharp edges and bright contrasts, which increases the chances of successful scanning.
3. Customizability: Vector graphics can be easily customized and edited using graphics software such as Adobe Illustrator. This makes it easier to integrate QR codes into your design and brand aesthetic.
4. File size: Vector images generally have smaller file sizes than raster images, which can be beneficial when uploading, sharing or saving your QR codes.

Although vector images are usually preferred when working with QR codes, there are situations where raster images are still useful. For example, if the QR code is displayed on a Web site and does not need to be scaled, a raster image such as high-resolution PNG may be sufficient. In this case, make sure the raster image is of high quality to ensure a successful scan.