minimp3

README

minimp3

Decode mp3 base on https://github.com/lieff/minimp3

Installation

1. The first need Go installed (version 1.15+ is required), then you can use the below Go command to install minimp3.

$ go get -u github.com/tosone/minimp3

1. Import it in your code:

import "github.com/tosone/minimp3"

Examples are here

Example1: Decode the whole mp3 and play.

package main

import (
	"io/ioutil"
	"log"
	"time"

	"github.com/hajimehoshi/oto"
	"github.com/tosone/minimp3"
)

func main() {
	var err error

	var file []byte
	if file, err = ioutil.ReadFile("test.mp3"); err != nil {
		log.Fatal(err)
	}

	var dec *minimp3.Decoder
	var data []byte
	if dec, data, err = minimp3.DecodeFull(file); err != nil {
		log.Fatal(err)
	}

	var context *oto.Context
	if context, err = oto.NewContext(dec.SampleRate, dec.Channels, 2, 1024); err != nil {
		log.Fatal(err)
	}

	var player = context.NewPlayer()
	player.Write(data)

	<-time.After(time.Second)

	dec.Close()
	if err = player.Close(); err != nil {
		log.Fatal(err)
	}
}

Example2: Decode and play.

package main

import (
	"io"
	"log"
	"os"
	"sync"
	"time"

	"github.com/hajimehoshi/oto"
	"github.com/tosone/minimp3"
)

func main() {
	var err error

	var file *os.File
	if file, err = os.Open("../test.mp3"); err != nil {
		log.Fatal(err)
	}

	var dec *minimp3.Decoder
	if dec, err = minimp3.NewDecoder(file); err != nil {
		log.Fatal(err)
	}
	started := dec.Started()
	<-started

	log.Printf("Convert audio sample rate: %d, channels: %d\n", dec.SampleRate, dec.Channels)

	var context *oto.Context
	if context, err = oto.NewContext(dec.SampleRate, dec.Channels, 2, 1024); err != nil {
		log.Fatal(err)
	}

	var waitForPlayOver = new(sync.WaitGroup)
	waitForPlayOver.Add(1)

	var player = context.NewPlayer()

	go func() {
		for {
			var data = make([]byte, 1024)
			_, err := dec.Read(data)
			if err == io.EOF {
				break
			}
			if err != nil {
				break
			}
			player.Write(data)
		}
		log.Println("over play.")
		waitForPlayOver.Done()
	}()
	waitForPlayOver.Wait()

	<-time.After(time.Second)
	dec.Close()
	if err = player.Close(); err != nil {
		log.Fatal(err)
	}
}

Example3: Play the network audio.

package main

import (
	"io"
	"log"
	"net/http"
	"os"
	"sync"
	"time"

	"github.com/hajimehoshi/oto"
	"github.com/tosone/minimp3"
)

func main() {
	var err error

	var args = os.Args
	if len(args) != 2 {
		log.Fatal("Run test like this:\n\n\t./networkAudio.test [mp3url]\n\n")
	}

	var response *http.Response
	if response, err = http.Get(args[1]); err != nil {
		log.Fatal(err)
	}

	var dec *minimp3.Decoder
	if dec, err = minimp3.NewDecoder(response.Body); err != nil {
		log.Fatal(err)
	}
	<-dec.Started()

	log.Printf("Convert audio sample rate: %d, channels: %d\n", dec.SampleRate, dec.Channels)

	var context *oto.Context
	if context, err = oto.NewContext(dec.SampleRate, dec.Channels, 2, 4096); err != nil {
		log.Fatal(err)
	}

	var waitForPlayOver = new(sync.WaitGroup)
	waitForPlayOver.Add(1)

	var player = context.NewPlayer()

	go func() {
		defer response.Body.Close()
		for {
			var data = make([]byte, 512)
			_, err = dec.Read(data)
			if err == io.EOF {
				break
			}
			if err != nil {
				log.Fatal(err)
				break
			}
			player.Write(data)
		}
		log.Println("over play.")
		waitForPlayOver.Done()
	}()

	waitForPlayOver.Wait()

	<-time.After(time.Second)
	dec.Close()
	player.Close()
}

Documentation

Index

• Variables
• type Decoder
  • func DecodeFull(mp3 []byte) (dec *Decoder, decodedData []byte, err error)
  • func NewDecoder(reader io.Reader) (dec *Decoder, err error)
  • func (dec *Decoder) Close()
  • func (dec *Decoder) Read(data []byte) (n int, err error)
  • func (dec *Decoder) Started() (channel chan bool)

Variables

var BufferSize = 1024 * 10

BufferSize Decoded data buffer size.

var WaitForDataDuration = time.Millisecond * 10

WaitForDataDuration wait for the data time duration.

Types

type Decoder

type Decoder struct {
	SampleRate int
	Channels   int
	Kbps       int
	Layer      int
	// contains filtered or unexported fields
}

Decoder decode the mp3 stream by minimp3

func DecodeFull

func DecodeFull(mp3 []byte) (dec *Decoder, decodedData []byte, err error)

DecodeFull put all of the mp3 data to decode.

func NewDecoder

func NewDecoder(reader io.Reader) (dec *Decoder, err error)

NewDecoder decode mp3 stream and get a Decoder for read the raw data to play.

func (*Decoder) Close

func (dec *Decoder) Close()

Close stop the decode mp3 stream cycle.

func (*Decoder) Read

func (dec *Decoder) Read(data []byte) (n int, err error)

Read read the raw stream

func (*Decoder) Started

func (dec *Decoder) Started() (channel chan bool)

Started check the record mp3 stream started ot not.