SIGNAL ENCODING DEVICE AND METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To enhance the encoding efficiency by removing the characteristic or correlativity of a signal by LPC(linear predicted coding) analysis or pitch analysis to the signal waveform of a time base prior to orthogonal transformation in an encoding using orthogonal transformation. SOLUTION: The time base input signal from an input terminal 10 is transmitted to a normalization circuit part 11 and an LPC analyzing circuit 39. The normalization circuit 11 removes the correlation of the signal waveform by an LPC reverse filter 12 and a pitch reverse filter 13 to take the residue, which is then transmitted to an orthogonal transformation circuit 25. The LPC coefficient from the LPC analyzing circuit 39 and the pitch parameter from a pitch analyzing circuit 15 are transmitted to a bit assignment calculation circuit 41. A coefficient quantization part 40 quantizes the coefficient from the orthogonal transformation circuit 25 according to the assigned bit number from the bit assignment calculation circuit 41.