mp3

Documentation

Index

• Variables
• func Assert(file string) error
• func WriteMetadata(file string, m audio.Metadata) error
• type Encoder
  • func NewEncoder() *Encoder
  • func (e *Encoder) EncodeFromStdin(dec *exec.Cmd, path string, md audio.Metadata) ([]byte, error)
• type Metadata
  • func ReadMetadata(file string) (*Metadata, error)
  • func (m *Metadata) Comment() string
  • func (m *Metadata) Copyright() string
  • func (m *Metadata) EncodedBy() string
  • func (m *Metadata) EncoderSettings() string
  • func (m *Metadata) Encoding() audio.Codec
  • func (m *Metadata) EncodingBitrate() int
  • func (m *Metadata) Length() time.Duration
  • func (m *Metadata) OriginalFilename() string
  • func (m *Metadata) PrivateData() []byte
  • func (m *Metadata) Website() string
  • func (m *Metadata) Year() int

Variables

var ErrNotMP3 = errors.New("file is not an MP3")

var Stats struct {
	Assert           stat.Run
	ReadMetadata     stat.Run
	ReadMetadataMeta stat.Run
	ReadMetadataBrDu stat.Run
	ToolMP3INFO      stat.Run
	ToolEXIFTOOL     stat.Run
}

Functions

func Assert

func Assert(file string) error

func WriteMetadata

func WriteMetadata(file string, m audio.Metadata) error

Types

type Encoder

type Encoder struct {
	Path    string
	Quality int
}

func NewEncoder

func NewEncoder() *Encoder

func (*Encoder) EncodeFromStdin

func (e *Encoder) EncodeFromStdin(dec *exec.Cmd, path string, md audio.Metadata) ([]byte, error)

EncodeFromStdin takes a command that produces a decoded file on stdout, and pipes that through an mp3 encoder. It tags the MP3 with audio metadata received.

For example:

	enc := mp3.Encoder{q}
 dec := exec.Command("flac", "-c", "-d", src)
 bs, err = enc.EncodeFromStdin(dec, path, md.Metadata())

type Metadata

type Metadata struct {
	// Metadata is an interface that already implements:
	//
	//  Format() tag.Format
	//  FileType() tag.FileType
	//
	//  Title() string
	//  Album() string
	//  Artist() string
	//  AlbumArtist() string
	//  Composer() string
	//  Year() int
	//  Genre() string
	//  Track() (int, int)
	//  Disc() (int, int)
	//
	//  Picture() *tag.Picture
	//  Lyrics() string
	//  Raw() map[string]interface{}
	tag.Metadata
	// contains filtered or unexported fields
}

func ReadMetadata

func ReadMetadata(file string) (*Metadata, error)

Runtime stats:

audio.Identify        μ=5.221595ms, σ=6.688962ms, n=12233
audio.ReadMetadata    μ=69.826077ms, σ=89.871762ms, n=4694
flac.Identify         μ=-2562047h47m16.854775808s, σ=-2562047h47m16.854775808s, n=0
flac.ReadFileMetadata μ=2.412411ms, σ=4.72771ms, n=2399
flac.ReadMetadata     μ=2.399813ms, σ=4.72703ms, n=2399
mp3.Assert            μ=11.714µs, σ=2.509µs, n=2295
mp3.ReadMetadata      μ=140.255738ms, σ=82.368328ms, n=2295

Runtime stats:

audio.Identify        μ=5.497306ms, σ=6.697311ms, n=12233
audio.ReadMetadata    μ=71.437403ms, σ=96.427961ms, n=4694
flac.Identify         μ=-2562047h47m16.854775808s, σ=-2562047h47m16.854775808s, n=0
flac.ReadFileMetadata μ=2.538888ms, σ=5.32524ms, n=2399
flac.ReadMetadata     μ=2.526025ms, σ=5.324577ms, n=2399
mp3.Assert            μ=11.556µs, σ=2.889µs, n=2295
mp3.ReadMetadata      μ=143.417326ms, σ=94.047081ms, n=2295
mp3.ReadMetadataMeta  μ=2.657978ms, σ=5.662125ms, n=2295
mp3.ReadMetadataBrDu  μ=140.729045ms, σ=92.607449ms, n=2295
mp3.ToolMP3INFO       μ=-2562047h47m16.854775808s, σ=-2562047h47m16.854775808s, n=0
mp3.ToolEXIFTOOL      μ=-2562047h47m16.854775808s, σ=-2562047h47m16.854775808s, n=0

func (*Metadata) Comment

func (m *Metadata) Comment() string

func (*Metadata) Copyright

func (m *Metadata) Copyright() string

func (*Metadata) EncodedBy

func (m *Metadata) EncodedBy() string

func (*Metadata) EncoderSettings

func (m *Metadata) EncoderSettings() string

func (*Metadata) Encoding

func (m *Metadata) Encoding() audio.Codec

func (*Metadata) EncodingBitrate

func (m *Metadata) EncodingBitrate() int

func (*Metadata) Length

func (m *Metadata) Length() time.Duration

func (*Metadata) OriginalFilename

func (m *Metadata) OriginalFilename() string

func (*Metadata) PrivateData

func (m *Metadata) PrivateData() []byte

func (*Metadata) Website

func (m *Metadata) Website() string

func (*Metadata) Year

func (m *Metadata) Year() int