You can find this paper on the ERDAS website or through an online search.
The ECW (ECW Image Compression) compressor is a software tool used for compressing and decompressing ECW image files. ECW is a wavelet-based image compression format used for storing and transmitting large images, particularly in the fields of remote sensing, GIS, and satellite imaging.
by ERDAS (now part of Hexagon)
ECW Compressor 2.6 is a free software tool that allows you to compress and decompress ECW images. You can download it from various online sources, but ensure you're getting it from a reputable website to avoid any malware or viruses.