audio/vorbis: Use oggvorbis for browsers

audio/vorbis/decode.go

@@ -12,8 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build !js
-
 package vorbis
 
 import (

audio/vorbis/decode_js.go

@@ -1,127 +0,0 @@
-// Copyright 2016 Hajime Hoshi
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build js
-
-package vorbis
-
-import (
-	"errors"
-	"io"
-	"io/ioutil"
-
-	"github.com/gopherjs/gopherjs/js"
-	"github.com/hajimehoshi/ebiten/audio"
-)
-
-// TODO: This just uses decodeAudioData can treat audio files other than Ogg/Vorbis.
-// TODO: This doesn't work on iOS which doesn't have Ogg/Vorbis decoder.
-
-type Stream struct {
-	leftData   []float32
-	rightData  []float32
-	posInBytes int
-}
-
-func (s *Stream) Read(b []byte) (int, error) {
-	l := len(s.leftData)*4 - s.posInBytes
-	if l > len(b) {
-		l = len(b)
-	}
-	l = l / 4 * 4
-	for i := 0; i < l/4; i++ {
-		l := s.leftData[s.posInBytes/4+i]
-		r := s.rightData[s.posInBytes/4+i]
-		if 1 < l {
-			l = 1
-		}
-		if l < -1 {
-			l = -1
-		}
-		if 1 < r {
-			r = 1
-		}
-		if r < -1 {
-			r = -1
-		}
-		il := int16(l * ((1 << 15) - 1))
-		ir := int16(r * ((1 << 15) - 1))
-		b[4*i] = uint8(il)
-		b[4*i+1] = uint8(il >> 8)
-		b[4*i+2] = uint8(ir)
-		b[4*i+3] = uint8(ir >> 8)
-	}
-	s.posInBytes += l
-	if s.posInBytes == len(s.leftData)*4 {
-		return l, io.EOF
-	}
-	return l, nil
-}
-
-func (s *Stream) Seek(offset int64, whence int) (int64, error) {
-	next := int64(0)
-	switch whence {
-	case io.SeekStart:
-		next = offset
-	case io.SeekCurrent:
-		next = int64(s.posInBytes) + offset
-	case io.SeekEnd:
-		next = int64(len(s.leftData)*4) + offset
-	}
-	s.posInBytes = int(next)
-	return next, nil
-}
-
-func (s *Stream) Close() error {
-	return nil
-}
-
-func (s *Stream) Size() int64 {
-	return int64(len(s.leftData) * 4)
-}
-
-func Decode(context *audio.Context, src audio.ReadSeekCloser) (*Stream, error) {
-	b, err := ioutil.ReadAll(src)
-	if err != nil {
-		return nil, err
-	}
-	if err := src.Close(); err != nil {
-		return nil, err
-	}
-	s := &Stream{}
-	ch := make(chan error)
-
-	klass := js.Global.Get("OfflineAudioContext")
-	if klass == js.Undefined {
-		klass = js.Global.Get("webkitOfflineAudioContext")
-	}
-	if klass == js.Undefined {
-		return nil, errors.New("vorbis: OfflineAudioContext is not available")
-	}
-	// TODO: 1 is a correct second argument?
-	// At least, 1 works on Chrome and Firefox but not Safari.
-	oc := klass.New(2, 1, context.SampleRate())
-	oc.Call("decodeAudioData", js.NewArrayBuffer(b), func(buf *js.Object) {
-		s.leftData = buf.Call("getChannelData", 0).Interface().([]float32)
-		s.rightData = buf.Call("getChannelData", 1).Interface().([]float32)
-		close(ch)
-	}, func() {
-		ch <- errors.New("vorbis: decodeAudioData failed (Safari might not be able to decode Ogg/Vorbis).")
-		close(ch)
-	})
-	if err := <-ch; err != nil {
-		return nil, err
-	}
-	return s, nil
-}

audio/vorbis/vorbis.go

@@ -12,8 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build !js
-
 // Package vorbis provides Ogg/Vorbis decoder.
 package vorbis
 
@@ -21,22 +19,46 @@ import (
 	"io"
 	"runtime"
 
+	"github.com/hajimehoshi/ebiten/audio"
 	"github.com/jfreymuth/oggvorbis"
 )
 
 type decoded struct {
 	data       []float32
+	totalBytes int
 	posInBytes int
+	source     io.Closer
+	decoder    *oggvorbis.Reader
 }
 
 func (d *decoded) Read(b []byte) (int, error) {
-	total := len(d.data) * 2
+	total := d.totalBytes
 	l := total - d.posInBytes
 	if l > len(b) {
 		l = len(b)
 	}
+	if l < 0 {
+		return 0, io.EOF
+	}
 	// l must be even so that d.posInBytes is always even.
 	l = l / 2 * 2
+	for len(d.data) < (d.posInBytes+l)/2 {
+		// TODO: What if the channel is closed?
+		buffer := make([]float32, 4096)
+		n, err := d.decoder.Read(buffer)
+		if n > 0 {
+			d.data = append(d.data, buffer[:n]...)
+		}
+		if err == io.EOF {
+			if err := d.source.Close(); err != nil {
+				return 0, err
+			}
+			break
+		}
+		if err != nil {
+			return 0, err
+		}
+	}
 	for i := 0; i < l/2; i++ {
 		f := d.data[d.posInBytes/2+i]
 		s := int16(f * (1<<15 - 1))
@@ -58,7 +80,7 @@ func (d *decoded) Seek(offset int64, whence int) (int64, error) {
 	case io.SeekCurrent:
 		next = int64(d.posInBytes) + offset
 	case io.SeekEnd:
-		next = int64(len(d.data)*2) + offset
+		next = int64(d.totalBytes) + offset
 	}
 	d.posInBytes = int(next)
 	return next, nil
@@ -70,22 +92,23 @@ func (d *decoded) Close() error {
 }
 
 func (d *decoded) Size() int64 {
-	return int64(len(d.data) * 2)
+	return int64(d.totalBytes)
 }
 
 // decode accepts an ogg stream and returns a decorded stream.
-func decode(in io.ReadCloser) (*decoded, int, int, error) {
+func decode(in audio.ReadSeekCloser) (*decoded, int, int, error) {
-	data, format, err := oggvorbis.ReadAll(in)
+	// TODO: Lazy evaluation
+	r, err := oggvorbis.NewReader(in)
 	if err != nil {
 		return nil, 0, 0, err
 	}
-	if err := in.Close(); err != nil {
-		return nil, 0, 0, err
-	}
 	d := &decoded{
-		data:       data,
+		data:       []float32{},
+		totalBytes: int(r.Length()) * 4, // TODO: What if length is 0?
 		posInBytes: 0,
+		source:     in,
+		decoder:    r,
 	}
 	runtime.SetFinalizer(d, (*decoded).Close)
-	return d, format.Channels, format.SampleRate, nil
+	return d, r.Channels(), r.SampleRate(), nil
 }