For those that are interested when there is a bit-error, or even multiple bit errors, I do suggest reading about how it works, not the inaccurate guess stated below. Interpolation only occurs when errors cannot be corrected. There are multiple levels of error correction and fully 25% of the data on a CD is redundant. If you don’t scratch your CDs, then you will have almost no unfixable errors on your whole CD.
Contrary to what many believe, you don’t have data bits and error correction bits all closely packed physically, they are spaced around the CD to reduce the impact of scratches. You don’t have a "good byte" on either side that is used to guess the one in the middle. That is not remotely what happens. That only happens if the scratches / defects are so severe that error correction cannot correct them. The methodology used for CDs allow full correction of up to 4000 bits, or about 2.5mm:
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.462.3524&rep=rep1&type=pdf
Contrary to what many believe, you don’t have data bits and error correction bits all closely packed physically, they are spaced around the CD to reduce the impact of scratches. You don’t have a "good byte" on either side that is used to guess the one in the middle. That is not remotely what happens. That only happens if the scratches / defects are so severe that error correction cannot correct them. The methodology used for CDs allow full correction of up to 4000 bits, or about 2.5mm:
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.462.3524&rep=rep1&type=pdf
For those interested in what happens when a byte can’t be read.
If a scratch has created read errors, you’re not completely hosed., "there is a pretty good chance that an uncorrected byte still has a good byte on either side". If that’s the case, then your CD player will take an average for those two values "and make an "educated guess" about what the missing value should be in between".
If the number of missing bytes gets to be too large, the system will suppress the error by muting the sound for a fraction of a second, which is hopefully too short a period of time to be detected.