ECW (Enhanced Compressed Wavelet) is a proprietary wavelet compression image format developed by ERDAS (now part of Hexagon Geospatial). It is primarily used for geospatial imagery, particularly large raster datasets like aerial photographs, satellite imagery, and scanned maps. ECW files are known for their high compression ratios while maintaining good image quality, making them suitable for storing and distributing large images efficiently. The wavelet compression technique allows for progressive decoding, meaning that lower-resolution versions of the image can be quickly displayed before the full resolution is loaded. This is particularly useful for web-based mapping applications and other scenarios where bandwidth is limited. ECW supports various georeferencing and metadata standards, making it compatible with GIS software and workflows. The format is often used in industries such as surveying, mapping, remote sensing, and defense.