Submodule compress.zstd¶

Overview¶

The compress.zstd submodule provides the ability to compress and decompress data using the zstd algorithm. You can use the zstd compressor as follows:

Create a compressor instance using the compress.zstd.new() function:

local zstd_compressor = require('compress.zstd').new()
-- or --
local zstd_compressor = require('compress').zstd.new()

Optionally, you can pass compression options (zstd_opts) specific for zstd:

local zstd_compressor = require('compress.zstd').new({
    level = 5
})

To compress the specified data, use the compress() method:

compressed_data = zstd_compressor:compress('Hello world!')

To decompress data, call decompress():

decompressed_data = zstd_compressor:decompress(compressed_data)

API Reference¶

Functions
compress.zstd.new()	Create a `zstd` compressor instance.
Objects
zstd_compressor	A `zstd` compressor instance.
zstd_opts	Configuration options of the `zstd` compressor.

compress.zstd.new()¶

new([zstd_opts])¶

Create a zstd compressor instance.

Parameters: options (table) – zstd compression options (see zstd_opts)
Returns: a new zstd compressor instance (see zstd_compressor)
Return type: userdata

Example

local zstd_compressor = require('compress.zstd').new({
    level = 5
})

zstd_compressor¶

class zstd_compressor¶

A compressor instance that exposes the API for compressing and decompressing data using the zstd algorithm. To create the zstd compressor, call compress.zstd.new().

compress(data)¶

Compress the specified data.

Parameters: data (string) – data to be compressed
Returns: compressed data
Return type: string

Example

compressed_data = zstd_compressor:compress('Hello world!')

decompress(data)¶

Decompress the specified data.

Parameters: data (string) – data to be decompressed
Returns: decompressed data
Return type: string

Example

decompressed_data = zstd_compressor:decompress(compressed_data)

zstd_opts¶

class zstd_opts¶

Configuration options of the zstd_compressor. These options can be passed to the compress.zstd.new() function.

Example

local zstd_compressor = require('compress.zstd').new({
    level = 5
})

level¶: Specifies the zstd compression level that enables you to adjust the compression ratio and speed. The lower level improves the compression speed at the cost of compression ratio. For example, you can use level 1 if speed is most important and level 22 if size is most important.

Default: 3

Minimum: -131072

Maximum: 22

Note

Assigning 0 to level resets its value to the default (3).

Version:

Submodule compress.zstd¶

Overview¶

API Reference¶

compress.zstd.new()¶

zstd_compressor¶

zstd_opts¶