Compression

import { read } from "mscompress";

const f = read("in.mzML");
f.arguments.threads = 8;
f.arguments.zstdCompressionLevel = 9;
f.compress("out.msz");
f.close();

RuntimeArguments

All compression knobs live on f.arguments:

Field	Type	Default	Purpose
threads	number	auto (CPU count)	Worker thread count
blocksize	number	100 MB	Bytes per ZSTD block
zstdCompressionLevel	number	3	1 (fast) … 22 (max)
mzLossy	string	""	Algorithm name (delta32, ...)
intLossy	string	""	Algorithm name
mzScaleFactor	number	algorithm default	Quantization
intScaleFactor	number	algorithm default	Quantization
targetMzFormat	string	"zstd"	"zstd" or "none"
targetIntenFormat	string	"zstd"	"zstd" or "none"
targetXmlFormat	string	"zstd"	"zstd" or "none"

Lossy compression

f.arguments.mzLossy = "delta32";
f.arguments.intLossy = "log";
f.compress("out.msz");

See Choosing a profile and the algorithm catalog for what each setting trades.