Awesome
pcm-convert
Convert data from one pcm-format to another.
Usage
const convert = require('pcm-convert')
//convert data from float32 to uint8 array
let uint8arr = convert([0, 0.1, 0.1, 0], 'float32', 'uint8')
//convert interleaved uint8 to planar float32 array
let float32arr = convert(new Uint8Array([127, 200, 127, 200]), 'uint8 stereo interleaved', 'float32 planar')
//deinterleave keeping the same data type
let int8arr = convert(new Int8Array([-100,100,-100,100]), 'interleaved', 'planar')
//change endianness keeping the same data type
let float32be = convert(new Float32Array([1,.5,-.5,-1]), 'le', 'be')
//use objects as formats
let float64 = convert(float32be, {
dtype: 'float32',
channels: 2,
interleaved: false,
endianness: 'be'
}, {
dtype: 'float64',
interleaved: true,
endianness: 'le'
})
//skip source format string, convert directly to data format
let uint16 = convert(new Uint8Array([0,255]), 'uint16')
//put data into target container skipping format strings
convert(new Uint8Array([0,255]), new Uint16Array(2))
//full arguments case
let uint16arr = convert([0, 0, 1, 1], 'float32 le stereo planar', 'uint16 interleaved be', new Uint16Array(4))
API
convert(src, srcFormat?, dstFormat?, dst?)
Takes data in src
container and converts from srcFormat
to dstFormat
. Format can be whether a string with tags or an object with properties, see audio-format module. If srcFormat
is skipped, it is detected from src
. Optionally a destination container can be provided as dst
, and in case if dstFormat
is skipped, it will be detected from dst
.
Source
Source format is inferred from src
data type and extended with srcFormat
properties. By default source is considered planar mono le
. Source data types:
Type | Dtype |
---|---|
Array | float32 |
Float32Array | float32 |
Float64Array | float64 |
ArrayBuffer | uint8 |
Buffer | uint8 |
Uint8Array | uint8 |
Uint8ClampedArray | uint8 |
Uint16Array | uint16 |
Uint32Array | uint32 |
Int8Array | int8 |
Int16Array | int16 |
Int32Array | int32 |
Format
Can be defined as dtype
string with tags, eg. 'uint8 interleaved mono le'
, 'float64 planar quad'
(some tags can be skipped), or an object with the following properties:
Property | Meaning |
---|---|
dtype | Data type string: uint8 , uint16 , uint32 , int8 , int16 , int32 , float32 , float64 , array (only dstFormat ), arraybuffer (only dstFormat ). |
interleaved | Boolean indicating if data has interleaved or planar layout. |
channels | Number of channels in source: mono , stereo , quad , 5.1 . |
endianness | be or le , defaults to OS endianness. |
Related
- audio-format - audio format notation parser/stringifier.
- audio-speaker - output data to speaker in node.
- dtype - list of standard data types.
License
© 2017 Dima Yv. MIT License