Make compression of zstd archive type more similar to zstdcli #354
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…le compression (slightly better performance and/or compression ratio); although the feature still calling as "experimental", but zstd uses this in its own client since v.1.4 IIRC and the only known drawback would be significant regress of compression ration if guess considerably underestimates, but it does no matter in case of known file size.
…store dictID and checksum by default in zstd type, no effect for 7z type)
…e unpackSize will be supplied as -1 (`UINT64_MAX`)
mcmilk
approved these changes
Sep 17, 2023
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This PR sets several parameters to zstd compression that forces it to work more similar to standard zstd client + few small fixes:
set source size as hint if it is known e. g. by file compression (slightly better performance and/or compression ratio);
although the feature still calling as "experimental", but zstd uses this in its own client since v.1.4 IIRC and the only known drawback would be significant regress of compression ratio if guess considerably underestimates, but it does no matter in case of known file size.
make compression of zstd archive type more similar to Zstandard CLI (store dictID and checksum by default in zstd type); this has no effect for 7z archive type with zstd method
brotli: small amend that avoid setting of size hint if
-sispecified (size is unknown)After all 7z would create almost the same compressed data as standard zstd-cli (can deviate by 1-2 bytes in header).