Abstract: A voice encoding/decoding method and apparatus. A voice encoder includes: a quantization selection unit generating a quantization selection signal; and a quantization unit extracting a linear prediction coding (LPC) coefficient from an input signal, converting the extracted LPC coefficient into a line spectral frequency (LSF), quantizing the LSF with a first LSF quantization unit or a second LSF quantization unit based on the quantization selection signal, and converting the quantized LSF into a quantized LPC coefficient. The the quantization selection signal selects the first LSF quantization unit or second LSF quantization unit based on characteristics of a synthesized voice signal in previous frames of the input signal.

Abstract: A method, medium, and apparatus for generating a record sentence to establish a speech corpus, including generating a synthesized sentence of speech and synthesis information related to speech synthesis by performing speech synthesis for a predetermined sentence of text, selecting an unseen sentence including an unseen unit according to the synthesis information, generating a weight indicating a recording priority of the unseen unit included in the selected unseen sentence, and generating a record sentence by combining the unseen unit with the speech synthesis information according to the generated weight.