Quantum Archive File Structure
File header
| Bytes | Description |
|---|---|
| 2 | Quantum signature: 0x44 0x53 |
| 1 | Quantum major version number |
| 1 | Quantum minor version number |
| 2 | number of files within this archive |
| 1 | table size required for decompression |
| 1 | compression flags |
This is immediately followed by the list of files:
| Bytes | Description |
|---|---|
| variable | length of file name, see (*) below |
| variable | file name, variable length string, not zero-terminated |
| variable | length of comment field, see (*) below |
| variable | comment field, variable length string, not zero-terminated |
| 4 | fully expanded file size in bytes |
| 2 | file time (DOS format) |
| 2 | file date (DOS format) |
Immediately following the list of files is the compressed data.
(*) Strings are prefixed with their length. If the length is less than 128 then it is stored directly in one byte. If it is greater than 127 then the high bit of the first byte is set to 1 and the remaining fifteen bits contain the actual length in big-endian format.
Read more about this topic: Quantum Compression
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