Patent ID: 7549106

Claim:
A method of correcting errors contained in a quality ranked data stream comprising: at a bit quality evaluator, assigning a level of correctness to each bit value in a data stream, wherein the level of correctness is a range of values indicative of a probability that the bit value is correct, identifying a bit as a poor quality bit if its level of correctness is approximately within the middle of the range of correctness values, tagging the poor quality bits with tagging data, and sending the data stream and the tagging data to an error detector and a first decoder; at the first decoder, receiving the data stream and tagging data, decoding the data stream, and sending the decoded data stream to a second decoder; at the error detector, determining whether a concentration of poor quality bits within a sliding window of bits in the data stream exceeds a concentration threshold based on the tagging data, predicting that the first decoder will fail to correct errors when the concentration of poor quality bits within the sliding window exceeds the concentration threshold, and instructing the second decoder to perform erasure on symbols likely to contain errors based on the tagging data; and at the second decoder, outputting decoded corrected data.