Image Formats

Rasterized Formats

Rasterized images come in many different formats, but they basically all follow the same concept: they are stored in a grid, with each cell in the grid containing information about the color of that cell. The most common raster formats are JPG, GIF, PNG and TIFF.

JPG (or JPEG)

Most common raster image. JPG is often used for digital cameras. Big disadvantages is the lossy compression: some image information will be lost, which can be mitigated by the use of the JPG image quality selector.

GIF (Graphic Interchange Format)

Was initally developed to allow color images to perform better on internet, while keeping the image size small. It’s good for animation, but it scores lower on image quality and color depth.

PNG (Portable Network Graphics)

PNG as developed to replace GIF as image format for internet media: better support for color space (24-bit RGB and 32-bit RGBA), support of transparant backgrounds and lossless data compression. The lack of CYMK support makes PNG not suitable for print media. Unlike GIF, it doesn’t support animations.

TIFF (Tagged Image File Format)

TIFF was developed to be used by image manipulation and design software. Therefore, it is mostly used in desktop publishing and print media design. It supports layers and pages. As TIFF is currently owned by Adobe, the support for TIFF in other software can be limited. Larger images sizes and limited browser support are other downsides of TIFF.

Vector Formats

Vector based images are a set of instructions for how to create an image from a predefined set of moves (lines, ellipse, etc) Major advantage of vector based images is that they can be scaled to almost any size withoud losing image quality. The most common vector formats are SVG and PDF.

SVG (Scalable Vector Graphics)

SVG is a common vector graphics implementation, where the instructions are written in XML format. SVG supports basic shapes, text, fills, gradients, interactivity and animations. Due to their text based format SVG’s are also quite a small file size and such are extra suitable for the web.

PDF (Portable Document Format)

PDF is a scalable format for documents, abstracted from the software that the file originated from. It initially started with basic text, image, and line style formatting, but it has expanded to include the ability to have scripting, interactive forms, embedded raster and vector images, and embedded videos. PDF’s is one of the most flexible file formats. It has become de facto standard.