PICTURE COMPRESSION SYSTEM

摘要

PURPOSE:To attain efficient transmission while reducing quantity of codes in an excellent picture by obtaining a 2nd-order difference as to a 1st-order difference in a direction of line for each picture element, selecting variable length coding for data whose zero concentration is stronger than certain value and selecting fixed length coding for data with more weak zero concentration than the value. CONSTITUTION:The 2nd-order difference for each picture element is obtained as to the 1st-order difference in a direction of the line and zero concentration is obtained by a zero concentration calculation circuit 41 depending on the smaller spread of the distribution such as the deviation of the 2nd-order difference and a fixed length/variable length selection circuit 42 selects the variable length coding to a data having the strong zero concentration and selects the fixed length coding to a data having the weak zero concentration based on the calculated zero concentration, and then the variable sampling density coding circuit 4 applies the variable sampling density coding in the direction of line as to the 1st-order difference. Thus, the entire quantity of code is saved.