PSeitz / lz4-wasm

https://pseitz.github.io/lz4-wasm/

lz4-wasm and lz4-wasm-nodejs

Extremely fast compression(200MB/s Firefox, 350Mb/s Chrome) and decompression(600MB/s Firefox, 1400Mb/s Chrome) in the browser or nodejs using wasm.

Benchmarks

Test it yourself here: https://pseitz.github.io/lz4-wasm/

Input	Lib	Compression	Decrompression	Ratio
66k_JSON	lz4 wasm	292.43MB/s	687.37MB/s	0.23
66k_JSON	lz4 js	101.48MB/s	27.06MB/s	0.24
66k_JSON	fflate	24.21MB/s	117.80MB/s	0.17
65k Text	lz4 wasm	146.10MB/s	610.59MB/s	0.55
65k Text	lz4 js	73.55MB/s	28.15MB/s	0.56
65k Text	fflate	15.40MB/s	63.83MB/s	0.41
34k Text	lz4 wasm	159.57MB/s	562.43MB/s	0.57
34k Text	lz4 js	59.77MB/s	28.10MB/s	0.58
34k Text	fflate	15.53MB/s	55.79MB/s	0.41
1k Text	lz4 wasm	181.25MB/s	362.50MB/s	0.78
1k Text	lz4 js	2.18MB/s	45.31MB/s	0.77
1k Text	fflate	5.49MB/s	3.64MB/s	0.53

🚴 Usage

There are two npm packages:

• nodejs lz4-wasm-nodejs
• browser lz4-wasm

See usage examples in this repo for browser and nodejs

The wasm module exposes two function compress and decompress. Both accept and return UInt8Array. Internally the lz4 block api is used, the length of the original input is prepended in 32-bit little endian. The wasm code is based on lz4_flex

import * as wasm from "lz4-wasm";

// use TextEncoder to get bytes (UInt8Array) from string
var enc = new TextEncoder();
const compressed = wasm.compress(enc.encode("compress this text, compress this text pls. thx. thx. thx. thx. thx"));
const original = wasm.decompress(compressed);

var dec = new TextDecoder("utf-8");
alert(dec.decode(original))

Making New Releases

Release for bundler

Build. This will optimize usage for inside a bundler like webpack.

RUST_LOG=info wasm-pack build --release

Due to a long standing bug in wasm-pack 0.9.1, manually add these files to pkg/package.json.

    "lz4_wasm_bg.wasm.d.ts",

RUST_LOG=info wasm-pack publish

Release for nodejs

set name in Cargo toml to

name = "lz4-wasm-nodejs"

Build for nodejs

RUST_LOG=info wasm-pack build --release -t nodejs

RUST_LOG=info wasm-pack publish