1. A distributed decoding device using a multi-core processor, comprising: a multi-core processor that includes a plurality of cores; a divider that receives an encoded data, extracts decoding information from the encoded data, divides the encoded data into slices, and generates and provides a single-slice decoding function, wherein the decoding function separately decodes one slice, such that threads for decoding the divided slices allocated thereto are distributed to the plurality of cores within the multi-core processor; a memory that includes a plurality of buffers which receive the slices from the divider to store therein and provides the stored slices to the plurality of cores of the multi-core processor; and a merger that merges the output data from the plurality of cores so as to produce the decoded data for the encoded data.