1. A method of processing an audio signal, comprising: obtaining, by a decoder, sample information from the audio signal indicating a total number of audio data samples for each channel in the audio signal, the audio signal having at least one channel subdivided into a plurality of blocks according to a subdivision hierarchy, the subdivision hierarchy having more than one level, each level being associated with a different block length, at least two of the plurality of blocks being capable of different lengths, wherein a value of the sample information is defined by an encoder; obtaining, by the decoder, frame length information from the audio signal indicating a number of samples in a frame of each channel, wherein a value of the frame length information is defined by the encoder; determining, by the decoder, if a remainder exists when the sample information is divided by the frame length information; determining, by the decoder, the number of frames in the audio signal as an integer value derived from the sample information divided by the frame information plus one if the determining step determines that the remainder exists; setting, by the decoder, a length of a last frame in the audio signal based on the remainder if the determining step determines that a remainder exists; obtaining, by the decoder, first subdivision information indicating whether the channel has been subdivided and second subdivision information indicating the subdivision of the channel into the plurality of blocks if the first subdivision information indicates the channel has been subdivided; decoding, by the decoder, the data samples based on the determined number of frames and the obtained first and second subdivision information, wherein a length of the second subdivision information depends on a number of levels in the subdivision hierarchy, wherein the first subdivision information indicates whether the subdivision hierarchy includes one of up to three levels, four levels, and five levels, if the first subdivision information is 01, the first subdivision information indicates the subdivision hierarchy includes up to three levels, if the first subdivision information is 10, the first subdivision information indicates the subdivision hierarchy includes four levels, if the first subdivision information is 11, the first subdivision information indicates the subdivision hierarchy includes five levels; obtaining, by the decoder, indicator information indicating whether determining of an optimum predication order for each block is allowed, a prediction order indicating a number of prediction coefficients; obtaining, by the decoder, the optimum predication order for each block based on a maximum permitted prediction order and a length of the block if determining of the optimum predication order for the bock is allowed; predicting, by the decoder, current data samples in the channel based on the optimum predication order; and obtaining, by the decoder, a residual of the current data samples based on the predicated data samples; wherein the optimum predication order indicates a minimum one of a global predication order and a local predication order, the global predication order having been determined based on the maximum permitted predication order, the local predication order having been determined based on the length of the block.