Embedding a watermark includes receiving a datastream of repeated values, determining if an end of run mode permits embedding a first or second binary value, transmitting a shortened version of the datastream when the next bit is a first binary value, appending to the datastream a redundant codeword indicating when the next bit is a first binary value and transmitting an unshortened version of the repeated data values to indicate the next bit is a second binary value and appending a conventional codeword from the codespace indicating the end of run mode and second binary value. Extracting a watermark bit-sequence includes determining if an end of run mode could have embedded either binary value, indicating a first binary value when the end of run mode uses a redundant codeword from the codespace and indicating a second binary value when the end of run mode uses a conventional codeword.