Picture signal processing system having improved quantizer

A picture signal processing system comprising:

• an orthogonal transformer for performing an orthogonal transformation upon a group of picture signals to generate transformed coefficients G;
• a first memory means for storing non-negative integers A' in accordance with frequency components of the transformed coefficients G;
• a second memory means for storing non-negative integers B' in accordance with the frequency components of the transformed coefficients G;
• a third memory means for storing signs S in accordance with the frequency components of the transformed coefficients G;
• a counter, connected to said orthogonal transformer, and to said first, second and third memory means for generating an address signal by counting the transformed coefficients G and reading said first and second memory means by the address signal, said counter being reset by every group of the transformed coefficients;
• a first right shifter, connected to said orthogonal transformer and to said first memory means, for shifting each of the transformed coefficients G in the right direction by a number of bits corresponding to the integer A' read from said first memory means;
• an adder, connected to said orthogonal transformer and to said first shifter, for adding the output of said first shifter to each of the transformed coefficients G;
• a subtractor, connected to said orthogonal transformer and to said first shifter, for subtracting the output of said first shifter from each of the transformed coefficients G;
• a selector, connected to said adder, to said subtractor, and to said third memory means, for selecting one of the outputs of said adder and said subtractor in accordance with the sign S read from said third memory means;
• and
• a second right shifter, connected to said selector, for shifting the output of said selector on the right direction by a number of bits corresponding to the integer B' read from said second memory means.