Patent ID: 7822616

Claim:
A method of decoding an audio signal performed by an audio player, comprising: receiving an audio signal including at least one frame, the frame comprising at least one time slot and at least one parameter set; determining a frame type of the audio signal, the frame type indicating whether an interval of a time slot to which a corresponding parameter set is applied is equidistant or variable distant, wherein when the frame type indicates that the interval of the time slot is variable distant, comprising extracting a number of time slots and a number of parameter sets from the audio signal to identify time slot information, the time slot information indicating a time slot to which a parameter set is applied; determining a bit length of the time slot information, the bit length being variable according to the number of time slots and the number of parameter sets; and extracting the time slot information based on the bit length, wherein a number of the time slot information is equal to the number of parameter sets; and converting the audio signal into a multi-channel audio signal based on the time slot information and the parameter set, and wherein the time slot information includes an absolute value indicating a time slot to which a first parameter set is applied or a difference value indicating a time slot to which a following parameter set of the first parameter set is applied, wherein the time slot to which the following parameter set is applied is determined by adding the difference value to previous time slot information associated with a previous parameter set; controlling information regarding the multi-channel audio signal to an audio subsystem for converting the multi-channel audio signal; transmitting the multi-channel audio signal or the audio signal to external unit; converting the multi-channel audio signal into a multi-channel analog output signal; and outputting at least one channel of the multi-channel analog output signal.