Jarosław Duda (computer scientist)

Life and career

Jarosław Duda was born in Dębica, Poland, in the Subcarpathian Voivodeship. After finishing King Władysław Jagiełło High School No. 1 in Dębica in 1999, he went on to earn three master’s degrees from Jagiellonian University in Kraków: one in computer science in 2004, another in pure mathematics in 2005, and a third in physics in 2006. He then completed two doctorates at the same university, one in theoretical computer science in 2010 and another in theoretical physics in 2012. In 2013, he spent a year as a postdoctoral fellow at Purdue University’s NSF Center for Science of Information, invited by Wojciech Szpankowski. He became an assistant professor at Jagiellonian University’s Institute of Computer Science and Computational Mathematics in 2015.

From 2006 to 2014, Duda created a set of entropy coding methods known as asymmetric numeral systems, or ANS, which are widely used in data compression. ANS offers the compression efficiency of arithmetic coding while keeping processing costs similar to Huffman coding. Its tabled variant, tANS, uses a finite-state machine to handle large alphabets without multiplication. Major tech companies like Apple, Facebook, Google, and Linux have adopted ANS in products such as Facebook Zstandard, Apple LZFSE, CRAM, and JPEG XL. Duda always intended ANS to remain patent-free. In 2018, his efforts helped persuade Google to drop its ANS-related patent claims in the United States and Europe. However, in 2022, Microsoft received a US patent for modifications to rANS, a variant Duda introduced in 2013. Duda has voiced concerns that this could reduce ANS’s usefulness, as developers might avoid it over fear of infringement claims.