22.0.0: Difference between revisions

Alu (talk | contribs)
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A new NSO compression method was introduced.
A new NSO compression method was introduced.


This appears to be a slightly customized variant of zstd and is used when NSO [[NSO0#Flags|flags]] have bit 7 set.
This is a customized variant of zstd and is used when NSO [[NSO0#Flags|flags]] have bit 7 set.
* ZSTD_MAGICNUMBER is set to 0x4349425A (b'ZBIC') instead of standard 0xFD2FB528
* ZSTD_MAGICNUMBER is set to 0x4349425A (b'ZBIC') instead of standard 0xFD2FB528
* ZSTD_LEGACY_SUPPORT is set to 0
* ZSTD_LEGACY_SUPPORT is set to 0
* ZSTD_TRACE is set to 1, the version of zstd used is 1.5.7 (ZSTD_VERSION_NUMBER = 10507)
* ZSTD_TRACE is set to 1, the version of zstd used is 1.5.7 (ZSTD_VERSION_NUMBER = 10507)
* The code seems to fully match upstream otherwise
* FSE_readNCount is replaced with a BIC (Binary Interpolative Coding) version which improves compression of entropy tables significantly


=== [[NFC_services|nfc]] ===
=== [[NFC_services|nfc]] ===