Lempel–Ziv–Welch (LZW)
Compresión LZW
- Date
- 1984 · confidence high
- Place
- Sudbury, Massachusetts, United States
- Credited to
- Terry Welch
- Field
- Knowledge & symbols
What it is
A lossless compression algorithm that improves on Lempel and Ziv's LZ78, building a pattern dictionary on the fly. It became the most widely used universal compression method in computing, adopted by Unix compress and the GIF format.
Published by Welch in 1984 as an improvement on Lempel and Ziv's 1978 LZ78 algorithm.
What it led to
- adoption in the Unix compress utility from 1986
- use in the GIF image format from 1987
- patent disputes that spurred free alternatives such as DEFLATE/gzip