Decoding device for decoding product code and decoding method using the same

A decoding device for decoding a product code, comprising:

• an erasure flag processor, for setting a particular value or a non-particular value for a plurality of erasure flags according to a plurality of the confidence flags, wherein each symbol has a confidence flag and an erasure flag correspondingly and each confidence flag has a confidence flag value belonging to a confidence flag value group {C0 CP CP−1 . . . C2 C1}, in which the C0 represents that its corresponding symbol has a highest confidence level of being a correct symbol, the CP represents that its corresponding symbol has a sub-highest confidence level of being a correct symbol, and so on, as well as the C1 represents that its corresponding symbol has a lowest confidence level of being a correct symbol and p is an integer greater than 2;
• a decoder, coupled to the erasure flag processor, for correcting the symbols according to the erasure flags and outputting the corrected symbols;
• and
• a confidence flag processor, coupled to both the erasure flag processor and the decoder, for resetting the confidence flag values of the confidence flags according to the erasure flags and the corrected symbols.