A program readable by a computer, for causing the computer to function as an audio controller , the program comprising: means for storing an output characteristic of a playback signal for each usage environment of a speaker in an output characteristic storage unit ; picked-up image data acquisition means for acquiring picked-up image data on an installation area of the speaker , which includes the speaker; wherein the picked-up image data acquisition means is configured to acquire, as first picked-up image data, picked-up image data obtained by picking up an image of the installation area of the speaker so that boundaries on both sides of a wall behind the speaker are aligned with both edges of an angle of view , and is configured to further acquire, as second picked-up image data, picked-up image data obtained by picking up an image of the installation area of the speaker so that boundaries on both sides of a wall beside the speaker are aligned with both edges of an angle of view , usage environment identification means for identifying the usage environment of the speaker based on the picked-up image data acquired by the picked-up image data acquisition means wherein the usage environment identification means is configured to obtain a ratio between a width of the wall behind the speaker and a width of the speaker from the first picked-up image data, obtain a ratio between a width of the wall beside the speaker and a depth of the speaker from the second picked-up image data, and to identify, as the usage environment of the speaker, a size of the installation area of the speaker based on the ratio obtained from the second picked-up image data and the ratio obtained from the first picked-up image data; and output characteristic determination means for determining an output characteristic stored in the output characteristic storage unit in association with the usage environment identified by the usage environment identification means , as an output characteristic of a playback signal to be output from the speaker . means for storing an output characteristic of a playback signal for each usage environment of a speaker in an output characteristic storage unit ; picked-up image data acquisition means for acquiring picked-up image data on an installation area of the speaker , which includes the speaker; wherein the picked-up image data acquisition means is configured to acquire, as first picked-up image data, picked-up image data obtained by picking up an image of the installation area of the speaker so that boundaries on both sides of a wall behind the speaker are aligned with both edges of an angle of view , and is configured to further acquire, as second picked-up image data, picked-up image data obtained by picking up an image of the installation area of the speaker so that boundaries on both sides of a wall beside the speaker are aligned with both edges of an angle of view , usage environment identification means for identifying the usage environment of the speaker based on the picked-up image data acquired by the picked-up image data acquisition means wherein the usage environment identification means is configured to obtain a ratio between a width of the wall behind the speaker and a width of the speaker from the first picked-up image data, obtain a ratio between a width of the wall beside the speaker and a depth of the speaker from the second picked-up image data, and to identify, as the usage environment of the speaker, a size of the installation area of the speaker based on the ratio obtained from the second picked-up image data and the ratio obtained from the first picked-up image data; and output characteristic determination means for determining an output characteristic stored in the output characteristic storage unit in association with the usage environment identified by the usage environment identification means , as an output characteristic of a playback signal to be output from the speaker . <EOS>