A decoding method, medium, and apparatus capable of preventing error propagation and implementing parallel processing. A decoding method includes comparing encoding information with decoding information at synchronization points for detecting a transmission error, and continuing to decode the encoded data if both the encoding and decoding information match, or continuing to decode remaining data located beyond the corresponding synchronization point by limiting a transmission error region to between the corresponding synchronization point and an immediately previous synchronization point, with reference to the encoding information if the encoding and decoding information do not match. Furthermore, the encoded data of a plurality of regions are simultaneously decoded in parallel, with reference to the encoding information of a plurality of synchronization points. Therefore, it is possible to prevent error propagation by limiting the transmission error within a smallest possible length and to reduce a decoding time by using a parallel processing.