Students Professional
JA EN

#deflate

2 articles

01 ·Image Codecs·FREE·8 min read Why PNG Does Not Degrade — Prediction Filters and Deflate What it means to shrink a file without changing a single bit. Starting from why no compressor can shrink everything, then PNG's five row filters as prediction-and-residual, Deflate (LZ77 plus Huffman), and why photographs resist it while screenshots collapse. Ending with a decision procedure for choosing between PNG and JPEG. 02 ·Coding Theory·★ MEMBER·9 min read Entropy Coding from Scratch — From Huffman to Arithmetic Coding "Information content becomes code length" — that one line is all of compression. From Shannon's bound to building a Huffman code by hand, the integer-bit ceiling, the arithmetic coders and ANS that break it, and what is actually running inside JPEG, PNG, H.264 and zstd. Ending with how to diagnose a compression ratio that has stopped improving.