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您的住址: Cape Crozier
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How CD's really work
http://www.geffers.demon.co.uk/cd.html
Error-correcting codes or "How come a scratched CD can still play flawlessly?"
http://www.princeton.edu/~matalive/notes/module2/2a.pdf
老實說，沒仔細看，不過和之前說的類似，『錯誤發生的「次數」』≠『發生幾個錯誤的 Byte』
以第一個 Stage 來看，引述如下
引用:
The First Stage of Error Correction
We have seen that out of 32 bytes read from the CD as one "frame", we only use 24 bytes in our final data. Four of the bytes are used in the first stage of correction, the remaining four are not used till the second part. This first stage is called C1, if you like Correction one. At this point, we have 28 bytes of data, plus four bytes which help us locate any errors, just like in our previous section. Using some funky mathematics, we can detect if those 28 bytes are correct, and if not we can fix a single error straight away, making those 28 bytes good. If we cannot fix the error, there are now only a couple of options open. Some CD players attempt to fix two errors, which is possible if there really are just two errors, however the mathematics is not so reliable for more than two errors. Several errors could create a situtation that looks like only two errors, and we can end up with a frame that we think is good, but is in fact bad.
Having found a bad C1 frame, we do not know at this stage which bytes are in error, all we know is that there are at least two errors.......
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