Abstract: Method and system for adjusting or controlling a noise floor of a filtered signal for low frequencies. A filtered digital signal, having M bits, is processed to form an one-bit XOR signal. This XOR signal is added to the filtered signal to produce a modified filtered signal. A selected number of LSB bits of the modified filtered signal is removed to form a dithered filtered signal with a noise floor that is reduced for low frequencies.

Abstract: Method and system for indicating that at least one row or column of a DVD data block has an uncorrectable number of errors, by marking or flagging the corrupted codewords of a codeword with defect detect signals. When a column (or row) of the data block is found to contain more than a thereshold number of errors, a selected number w of distinguishable codeword values (DSVs) “x” is associated with at least one column (or with at least one row) of the block. When the block is further processed and the presence of more than a threshold number of DSVs is sensed, the system interprets this occurrence as indicating that an uncorrectable group of errors has occurred in a column and/or row of the block.

Abstract: Method and system for incdicating that at least one C2 codeword or C1 codeword of a CD data block has an uncorrectable number of errors, by marking or flagging the corrupted symbols of a codeword with defect signals. When a C1 codeword (or C2 codeword) of the data block is found to contain more than a threshold number of errors, a selected number w of distinguishable symbol values (DSVs) is associated with at least one C1 codeword (or with at least one C2 codeword) of the block. When the block is further processed and the presence of more than a threshold number of DSVs is sensed, the system interprets this occurrence as indicating that an uncorrectable group of errors has occurred in a C1 codeword and/or in a C2 codeword of the block.