ECW

From GISWiki

ECW (Enhanced Compression Wavelet) is an open standard developed by Earth Resource Mapping. The file format is optimized for aerial and satellite imagery, and efficiently compresses very large images with fine, alternating contrast. This is a format.

It has the following properties:

• embeds map projection information
• fast compression (about 1.5 MB of compressed file per second on 1 GHz processor)
• typical compression ratios between 1:10 and 1:100
• possible decompression of selected regions without the need to decompress the whole file
• data flow compression allows for compression of big files with small requirements

Weblinks

• Earth Resource Mapping homepage
• gisdevelopment.net - ECW (Wavelet compression for Digital Imagery and Image Web server)
• Ueffing - Wavelet based ECW image compression (PDF)
• ER Mapper Plugins Download Page
• Download Free ER Mapper ECW/JPEG2000 Compressor
• Download Free AU ECW Compressor
• IrfanView - Image viewer for Microsoft Windows View/read/write/convert ECW files. Freeware (for non-commercial use).]
• XnView - Image viewer for Windows, Mac OS X, Linux x86, Linux ppc, FreeBSD x86, OpenBSD x86, NetBSD x86, Solaris sparc, Solaris x86, Irix mips, HP-UX, AIX. View/read/write/convert ECW files. XnView provided as Freeware for private non-commercial, educational use and non-profit organization.]
• MapWindow GIS Mapwindow web site