Patent ID: 8718299

Claim:
An audio control device comprising: a digital audio signal receiver that receives first digital audio signals and second digital audio signals that are PDM digital audio signals in which a state is represented by 1 or 0 in each predetermined period, signal state of the PDM digital audio signals being represented by density of 1 and 0 in a predetermined time; and a generator that generates half-period digital audio signals, which are signals of a half period of the predetermined period and in which a state is represented by 1 or 0 in each half period, by reflecting the states of the first digital audio signals in one of corresponding two half periods, setting 1 in the other all half periods, and subtracting the states of the second audio signals from the corresponding other half periods, wherein, when the state of the first digital audio signal is 1 and the state of the second digital audio signal is 0, the generator generates the half-period digital audio signals whose states of the two half periods corresponding to the predetermined period are 1 1, respectively, when the states of both the first digital audio signal and the second audio signal are either 1 or 0, the generator generates the half-period digital audio signals whose states of the two half periods corresponding to the predetermined period are 1 0 or 0 1, respectively, and when the state of the first digital audio signal is 0 and the state of the second digital audio signal is 1, the generator generates the half-period digital audio signals whose states of the two half periods corresponding to the predetermined period are 0 0, respectively.