Method for data reproducing from an optical storage device
View Patent ↗A method for data reproducing from an optical storage device. The method is used to improve the usage efficiency of buffer memory of the storage device. Date that is already transferred to the host computer is considered as “cache hit”. Thus, when data near one address is read again, the storage device need not do tracking, reading and decoding. Data in buffer memory is directly transferred to the host computer. It significantly improves the reproducing efficiency of the optical storage device.
1. A method for data reproducing from an optical storage device with a buffer memory having first, second and third areas temporarily storing data to be read from an optical disk to a host, the method comprising the steps of:
(a) reading first data from the optical disk and storing the first data in the first area of the buffer memory;
(b) decoding the first data and storing the decoded first data in the second area of the buffer memory;
(c) transferring the decoded first data to the host and storing the transferred first data in the third area of the buffer memory; and
(d) transferring second data that is read from the optical disk directly from the second and third area of the buffer memory to the host when the second data exists in the second and third area, otherwise, repeating the steps (a)˜(d) until data reproducing is finished.
2. The method as claimed in claim 1 , wherein memory addresses in the second and third area are for Cache Hit.
3. The method as claimed in claim 2 , wherein the addresses for Cache Hit are located between T+X2+B−N and T+X1.
4. The method as claimed in claim 3 , wherein T is an memory address of the transferred first data, X2 is a difference between addresses of the read first data and the transferred first data, B is a boundary address of the buffer memory, N is the maximum size of the buffer memory, and X1 is a difference between addresses of the decoded first data and the transferred first data.
5. The method as claimed in claim 1 further comprising the step of:
transferring the first data that is read from the optical disk directly from the second and third area of the buffer memory to the host when the first data exists in the second and third area.