Definitions of image formats, compression techniques, and web performance terms.
JPEG XL is a next-generation image format designed to replace JPEG with better compression efficiency, lossless transcoding from existing JPEG files, ...
Progressive JPEG is an encoding method where the image loads in successive passes from blurry to sharp, giving users a preview of the full image befor...
A color space is a mathematical model that defines a specific range of colors that can be represented in an image, with sRGB being the web standard an...
An image CDN is a content delivery network specialized for serving optimized images, automatically converting formats, resizing dimensions, and adjust...
Chroma subsampling is a compression technique that reduces color information resolution while preserving full luminance detail, exploiting the human e...
An image sprite is a single image file containing multiple smaller images arranged in a grid, used to reduce HTTP requests by combining icons or UI el...
Responsive images are a set of HTML techniques using srcset and sizes attributes that serve differently-sized image files to different devices, ensuri...
Lazy loading is a performance optimization technique that defers loading of off-screen images until the user scrolls near them, reducing initial page ...
Image metadata is information embedded within an image file that describes properties like camera settings, GPS location, creation date, and copyright...
Lossy compression permanently removes image data that the human eye is unlikely to notice, achieving 60-90% file size reduction by discarding high-fre...
Web Workers are a browser API that enables running JavaScript in background threads separate from the main UI thread, allowing image processing operat...
OxiPNG is a multithreaded PNG optimizer written in Rust that reduces PNG file sizes by 20-70% through lossless recompression techniques including bett...
HEIF (High Efficiency Image Format) is the container format used by Apple devices for photos, offering 50% better compression than JPEG while supporti...
Image quantization is the process of reducing the number of distinct colors in an image to a smaller palette, typically from millions to 256 or fewer ...
SVG optimization is the process of reducing SVG file size by removing unnecessary metadata, simplifying paths, merging shapes, and minifying markup — ...
WebP is a modern image format developed by Google that provides superior lossless and lossy compression for web images.
AVIF is a next-generation image format based on the AV1 video codec that delivers exceptional compression efficiency.
Lossy compression reduces file size by permanently discarding some image data that is less perceptible to the human eye.
Lossless compression reduces file size without discarding any image data, allowing perfect reconstruction of the original.
Image optimization is the process of reducing image file sizes and delivering them efficiently to minimize page load times.
Batch processing applies the same operation to multiple files simultaneously rather than one at a time.
WebAssembly (WASM) is a binary instruction format that enables near-native execution speed for computation-heavy tasks in browsers.
An alpha channel is an additional data layer in an image that defines the transparency level of each pixel.
Core Web Vitals are Google's standardized metrics measuring real-world user experience for loading, interactivity, and visual stability.
EXIF data is metadata embedded in image files that records camera settings, location, date, and other capture information.