Image

An image is a visual representation that can be perceived by the eye. In common usage, it refers to a two-dimensional depiction produced by recording light on a surface or by rendering digital data into a grid of picture elements. Images range from photographs and drawings to diagrams and synthetic renders, and they may be static or moving.

Images can be categorized by how they are stored and rendered. Raster images use a grid of pixels, each with a color value, which enables rich detail but can lose quality when scaled. Vector images describe shapes and colors with mathematical formulas and remain crisp at any size. Color images use color models such as RGB for displays or CMYK for print; grayscale images use a single intensity channel.

Digital images are saved in various formats. Raster formats include JPEG (lossy), PNG (lossless), GIF (indexed color, limited animation), and TIFF (flexible lossless or lossy). Vector formats include SVG, EPS, and PDF. Modern formats like WebP and HEIF aim to combine compression efficiency with quality. Some formats support metadata and color management.

Image creation and capture occur with cameras, scanners, drawing and painting software, or 3D rendering engines. Image processing involves editing, filtering, compression, and analysis, often using algorithms for demosaicing, resampling, deconvolution, or enhancement. Resolution, color depth, and sampling rate affect quality and file size; higher resolution and color depth yield larger files.

Images play a central role in communication, art, science, and technology, serving as documentation, illustration, and input for computer vision and machine learning systems. They are interpreted contextually and culturally, and their authenticity and provenance can be important considerations.