3 months ago
- The article explores Joel Yliluoma's 2011 ordered dither algorithm and introduces simplified EMA variants.
- It compares these methods to Thomas Knoll's Photoshop dither algorithm, focusing on color selection for palette-based images.
- The EMA variants use exponential moving averages to pick candidate colors, with options for exact or constant mixing factors.
- Knoll's algorithm remains faster due to O(N log K) complexity, while Yliluoma-2 and EMA variants are O(NK).
- Dither quality depends on candidate count N and mixing factor t, with N around 2K recommended for K-color images.
- Source code is provided for implementations including Knoll, EMA, and offset dithers.