Class MpegProperties

Audio properties for MPEG (MP3) and ADTS (AAC) streams.

Reads frame headers to determine duration, bitrate, sample rate and channel layout. Handles both CBR and VBR (Xing / VBRI) streams.

Hierarchy (View Summary)

AudioProperties
- MpegProperties

Index

Properties

Accessors

bitrate channelMode channels isADTS isCopyrighted isOriginal layer lengthInMilliseconds lengthInSeconds protectionEnabled sampleRate version

Methods

Properties

`Protected`_readStyle

_readStyle: ReadStyle

The read style used when parsing the audio stream.

Accessors

bitrate

get bitrate(): number
Gets the average audio bitrate in kbps.

Returns number
Overrides AudioProperties.bitrate
- Defined in mpeg/mpegProperties.ts:69

channelMode

get channelMode(): ChannelMode
Gets the channel mode of the first audio frame.

Returns ChannelMode
- Defined in mpeg/mpegProperties.ts:92

channels

get channels(): number
Gets the number of audio channels.

Returns number
Overrides AudioProperties.channels
- Defined in mpeg/mpegProperties.ts:73

isADTS

get isADTS(): boolean
Gets whether the stream is an ADTS (AAC) stream.

Returns boolean
- Defined in mpeg/mpegProperties.ts:90

isCopyrighted

get isCopyrighted(): boolean
Gets whether the audio is flagged as copyrighted.

Returns boolean
- Defined in mpeg/mpegProperties.ts:86

isOriginal

get isOriginal(): boolean
Gets whether the audio is flagged as an original recording.

Returns boolean
- Defined in mpeg/mpegProperties.ts:88

layer

get layer(): number
Gets the MPEG layer number (1, 2, or 3); 0 for ADTS streams.

Returns number
- Defined in mpeg/mpegProperties.ts:82

lengthInMilliseconds

get lengthInMilliseconds(): number
Gets the duration of the audio stream in milliseconds.

Returns number
Overrides AudioProperties.lengthInMilliseconds
- Defined in mpeg/mpegProperties.ts:67

lengthInSeconds

get lengthInSeconds(): number
Duration rounded to the nearest second.

Returns number
Inherited from AudioProperties.lengthInSeconds
- Defined in audioProperties.ts:22

protectionEnabled

get protectionEnabled(): boolean
Gets whether CRC protection is enabled.

Returns boolean
- Defined in mpeg/mpegProperties.ts:84

sampleRate

get sampleRate(): number
Gets the audio sample rate in Hz.

Returns number
Overrides AudioProperties.sampleRate
- Defined in mpeg/mpegProperties.ts:71

version

get version(): MpegVersion
Gets the MPEG version of the first audio frame.

Returns MpegVersion
- Defined in mpeg/mpegProperties.ts:80

Methods

`Static`create

create(file: MpegFile, readStyle?: ReadStyle): Promise<MpegProperties>
Creates an MpegProperties instance by reading the audio stream from file.
Parameters
- file: MpegFile
  The MPEG file whose audio properties should be determined.
- readStyle: ReadStyle = ReadStyle.Average
  The level of detail to use when scanning the stream (default: ReadStyle.Average).
Returns Promise<MpegProperties>
A fully populated MpegProperties instance.
- Defined in mpeg/mpegProperties.ts:53