Quantization error is the main source of the Lossy Compression. Quality factor in most implementations is the scaling factor for default quantization tables. Maps 8 x 8 to a 1 x 64 vector 3d. Send off SSS as Huffman symbol, followed by actual 3 bits. Quantization tables Huffman Tables Arithmetic Coding Tables Comments Application Data 5.
Predictor uses linear combination of previously encoded neighbors.
It can be one of seven different predictor based on pixels neighbors Since it uses only previously encoded neighbors, first row always uses P2, first column always uses P1. Down-sample by factors of 2 in each direction. Can be repeated multiple times. Good for viewing high resolution image on low resolution display. Further Exploration Try the Interactive JPEG examples and the JPEG examples .