Sound processing method, sound processing apparatus, and recording medium

A sound processing apparatus comprising:

• a memory storing instructions;
• and
• at least one processor that implements the instructions to:
• obtain a first sound signal representative of a first sound, the first sound signal including a first spectrum envelope contour and a first reference spectrum envelope contour;
• obtain a second sound signal representative of a second sound differing in sound characteristics from the first sound, the second sound signal including a second spectrum envelope contour and a second reference spectrum envelope contour;
• generate a synthesis spectrum envelope contour by transforming the first spectrum envelope contour based on a first difference and a second difference, wherein:
• the first difference is present between the first spectrum envelope contour and the first reference spectrum envelope contour at a first time point of the first sound signal;
• and
• the second difference is present between the second spectrum envelope contour and the second reference spectrum envelope contour at a second time point of the second sound signal;
• and
• generate a third sound signal representative of the first sound that has been transformed using the generated synthesis spectrum envelope contour.

A non-transitory computer-readable recording medium storing a program executable by a computer to execute a sound processing method comprising:

• obtaining a first sound signal representative of a first sound, the first sound signal including a first spectrum envelope contour and a first reference spectrum envelope contour;
• obtaining a second sound signal representative of a second sound differing in sound characteristics from the first sound, the second sound signal including a second spectrum envelope contour and a second reference spectrum envelope contour;
• generating a synthesis spectrum envelope contour by transforming the first spectrum envelope contour based on a first difference and a second difference, wherein:
• the first difference is present between the first spectrum envelope contour and the first reference spectrum envelope contour at a first time point of the first sound signal;
• and
• the second difference is present between a second spectrum envelope contour and the second reference spectrum envelope contour at a second time point of the second sound signal;
• and
• generating a third sound signal representative of the first sound that has been transformed using the generated synthesis spectrum envelope contour.