| 摘要 |
PURPOSE:To efficiently encode a natural picture with high picture quality by obtained a residual by the first encoding to coarsely encode the flat part of the picture and finely encode the steep part of the picture and local decoding for the first encoding and executing the second encoding to encode the residual. CONSTITUTION:An index and a code string are supplied to an input terminal 41 and inputted to a reception circuit 42, and an initial value Si, an index (k), and a code F are separated. The index (k) is given to quantization table 43, and the table 43 outputs a sample number and a central value. An interpolation circuit 44 calculates an interpolation value from the sample number and the central value, and interpolated data are made into a difference value string and sent to an arithmetic circuit 45. In the arithmetic circuit 45, the initial value Si hold in an initial value updating circuit 46 is added to the product of the code F and a difference value S1, and the added result is made into a reproduced signal string. The final value of the reproduced signal string in the circuit 45 is sent to the circuit 46 and updates the preceding initial value Si. Encoded residual data are inputted from a terminal 47 to a residual decoding circuit 48, decoded into a residual signal data string with an operation opposite to another operation for encoding the residual, added with the reproduced signal data string, and outputted from a terminal 50. |
