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Kornel Lesiński

Kornel Lesiński
Developer, FT Labs

Website | @pornelski

Developer at FT Labs — an emerging web technologies team at the Financial Times.

Participant in web standards development at WHATWG and RICG.

Creator of ImageOptim. Independent image compression researcher and developer of lossy PNG compression tools: pngquant2 and ImageAlpha.


Office Hours
Location: Table B (Banquet Hall)
Kornel Lesiński (FT Labs)
Kornel is here to answer your questions about image compression pipeline: encoding, serving, and responsive images. He's also ready to chat about encoding images for the best filesize/quality ratio; guidelines for content negotiation, transcoding proxies, caching and offline storage; and the srcset attribute and the picture element—dealing with high-DPI (“Retina”) images. Read more.
Location: 212 Level: Intermediate
Kornel Lesiński (FT Labs)
Average rating: ****.
(4.47, 17 ratings)
PNG images with alpha transparency are incredibly useful in web design, but their large file sizes are at odds with good page performance. With a special encoder it's possible to create PNG images that are up to 40% smaller, and still compatible with all browsers, support smooth transparency and millions of colors. I'm going to show you how to do it, whether you're a designer or a developer. Read more.