Volt Documentation

Decompresses LZ4 compressed data.

Syntax

lz4decompress(data: string, size: number) -> string

Parameters

Parameter	Type	Description
`data`	`string`	The LZ4 compressed data
`size`	`number`	The original uncompressed size

Returns

Type	Description
`string`	The decompressed data

Description

lz4decompress decompresses data that was compressed with lz4compress. You must provide the original uncompressed size for the decompression to work correctly.

Example

local original = "This is the original data that will be compressed!"
local originalSize = #original

-- Compress
local compressed = lz4compress(original)

-- Decompress (need to know original size)
local decompressed = lz4decompress(compressed, originalSize)

print(original == decompressed) -- true

Storing Size with Data

When storing compressed data, you should also store the original size:

local function compressWithSize(data)
    local compressed = lz4compress(data)
    -- Prepend the size as a 4-byte integer
    local size = #data
    return string.pack("<I4", size) .. compressed
end

local function decompressWithSize(data)
    local size = string.unpack("<I4", data)
    local compressed = data:sub(5)
    return lz4decompress(compressed, size)
end

Notes

The size parameter must match the original data size exactly
Providing wrong size may cause errors or corrupted output

lz4compress - Compress with LZ4

lz4decompress

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