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Figuring out on which sector the next recording should start
(or where a crashed live recording starts)
============================================================
1. Find the start offset of the drive usage table, e.g. 0xa00
2. Find the suspected start offset of the live recording
in said table. This is the offset of the first 32-bit word
that is 0.
For instance the found offset is 0xe74
3. This means the recording starts on cluster
0xe74-0xa00=0x474
4. The superblock states the number of audio blocks per cluster,
offset 0x14. For the sake of this example, lets assume 9
audio blocks per cluster. The size of each audio block is on
offset 0x10, usually 0x480.
5. The first audio sector is mentioned on the superblock on
offset 0x7e. In most cases it is 0x1397f6.
6. Each byte in the drive usage table represents 8 clusters.
7. The audio should then start on
0x1397f6 + (0x480*9*8*(0xe74-0xa00)) = sector 0x5b667f6.
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The other way around- calculating offset from sector number:
(0x02e427f6 - 0x1397f6) / 0x480 / clusters /8 + 0xa00
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