ECW (Enhanced Compressed Wavelet) is a proprietary geospatial raster image format developed by ERDAS (now part of Hexagon Geospatial). It is designed for efficient storage and retrieval of very large imagery datasets, such as aerial photographs, satellite imagery, and scanned maps. ECW files employ wavelet compression, which allows for high compression ratios while maintaining good image quality. This makes them ideal for distributing and accessing large geospatial datasets over networks with limited bandwidth. The format supports multiple resolutions, allowing users to quickly view overview images and then zoom in to access finer details. ECW is commonly used in geographic information systems (GIS), remote sensing, and mapping applications. The compression algorithm is lossy, meaning some data is discarded during compression, but the goal is to minimize visual artifacts and preserve the overall information content of the image. ECW files often include georeferencing information, enabling them to be accurately positioned within a GIS environment. The format is particularly well-suited for handling large, continuous raster datasets, such as those covering entire countries or regions.