1. A method of processing an audio signal, comprising: obtaining sample information from the audio signal indicating a total number of audio data samples for each channel in the audio signal; obtaining frame length information from the audio signal indicating a number of samples in a frame of each channel; determining if a remainder exists if the sample information is divided by the frame length information; determining the number of frames in the audio signal as an integer value of the sample information divided by the frame information plus one if the determining step determines that a remainder exists; setting a length of a last frame in the audio signal based on the remainder if the determining step determines that a remainder exists; and decoding the data samples based on the determined number of frames.