DIGITAL SIGNAL ENCODING METHOD AND DECODING METHOD, DIGITAL SIGNAL ENCODER AND DECODER, RECORDING MEDIUM RECORDING DIGITAL SIGNAL ENCODING PROGRAM AND RECORDING MEDIUM RECORDING DIGITAL SIGNAL DECODING PROGRAM

摘要

PROBLEM TO BE SOLVED: To reduce generated code quantity, because information on the quantization width is not included in coded data, by deciding the quantization width in encoding a digital signal from the size of coded data that is already encoded and deciding the quantization width in decoding from the size of decoded data that is already received. SOLUTION: A small block dividing part 100 divides an input digital image signal into small block units, and an orthogonal transformation part 200 performs orthogonal transformation of a small block unit. A quantizing part 300 quantizes an orthogonal transformation coefficient as a result by quantization width that is outputted from a quantization width calculating part 500. A coded data generating part 400 encodes a quantization number that is a result of quantization processing and sends it. A coded data decoding part outputs code quantity information that is received to the quantization width calculating part, and a calculating part calculates quantization width information and supplies it to an inverse quantization part. A small block combining part returns data after inverse quantization to a state before small block division and outputs it as a coded digital signal.