Huffman Coding

In September 1992, a committee called the Joint Photographic Experts Group published a standard that would fundamentally change how humanity stores and shares images. The JPEG format, based on the discrete cosine transform (DCT), made digital photography practical by reducing file sizes by a factor of 10 while maintaining acceptable visual quality. Three decades later, JPEG remains the most widely used image format in the world, with billions of images created daily. ...

In 1952, a graduate student at MIT named David Huffman faced a choice: write a term paper or take a final exam. His professor, Robert Fano, had assigned a paper on finding the most efficient binary code—a problem that had stumped both Fano and Claude Shannon, the father of information theory. Huffman, unable to prove any existing codes were optimal, was about to give up and start studying for the final. Then, in a flash of insight, he thought of building the code tree from the bottom up rather than the top down. The result was optimal, elegant, and would become one of the most widely used algorithms in computing history. ...