Sound processing apparatus and method, and program
The present technology relates to a sound processing apparatus and method, and a program for enabling more stable localization of a sound image. A virtual speaker is assumed to exist on the lower side among the sides of a tetragon having its corners formed with four speakers surrounding a target sound image position on a spherical plane. Three-dimensional VBAP is performed with respect to the virtual speaker and the two speakers located at the upper right and the upper left, to calculate gains of the two speakers at the upper right and the upper left and the virtual speaker, the gains being to be used for fixing a sound image at the target sound image position. Further, two-dimensional VBAP is performed with respect to the lower right and lower left speakers, to calculate gains of the lower right and lower left speakers, the gains being to be used for fixing a sound image at the position of the virtual speaker. The values obtained by multiplying these gains by the gain of the virtual speaker are set as the gains of the lower right and lower left speakers for fixing a sound image at the target sound image position. The present technology can be applied to sound processing apparatuses.
1. A sound processing apparatus comprising:
a gain calculating unit configured to determine output gains of sounds to be output from at least four sound outputting units located close to a sound image localization position as a target position by calculating gains of sounds to be output from the sound outputting units based on a positional relationship between the sound outputting units with respect to each of different combinations among a plurality of combinations of two or three of the at least four sound outputting units, the output gains being to be used for fixing a sound image at the sound image localization position;
a gain adjusting unit configured to perform gain adjustment on sounds to be output from the sound outputting units based on the output gains;
a first gain calculating unit configured to calculate output gains of a virtual sound outputting unit and two of the sound outputting units based on a positional relationship among the virtual sound outputting unit, the two of the sound outputting units, and the normal sound image position;
a second gain calculating unit configured to calculate gains of other two of the sound outputting units than the two of the sound outputting units based on a positional relationship among the other two of the sound outputting units and the virtual sound outputting unit, the gains of the other two of the sound outputting units being to be used for fixing a sound image at a position of the virtual sound outputting unit; and
a calculating unit configured to calculate output gains of the other two of the sound outputting units based on the gains of the other two of the sound outputting units and the output gain of the virtual sound outputting unit.
2. The sound processing apparatus according to claim 1 , wherein at least four of the output gains each have a value other than 0.
3. The sound processing apparatus according to claim 1 , wherein the calculating unit calculates the output gains of the other two of the sound outputting units by multiplying the gains of the other two of the sound outputting units by the output gain of the virtual sound outputting unit.
4. The sound processing apparatus according to claim 1 , wherein the position of the virtual sound outputting unit is on a side of a polygon having the at least four sound outputting units at corners thereof.
5. The sound processing apparatus according to claim 2 , wherein the gain calculating unit includes:
a virtual gain calculating unit configured to calculate output gains of three of the sound outputting units based on a positional relationship among the three of the sound outputting units and the sound image localization position; and
a calculating unit configured to calculate ultimate output gains of the sound outputting units based on the output gains calculated by the virtual gain calculating unit calculating the output gains with respect to different combinations among the combinations.
6. The sound processing apparatus according to claim 5 , wherein the calculating unit calculates an ultimate output gain of the same one of the sound outputting units by determining a sum of the output gains determined with respect to the same one of the sound outputting units.