mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-12-25 11:18:54 +01:00
98 lines
2.8 KiB
Go
98 lines
2.8 KiB
Go
// Copyright 2017 The Ebiten Authors
|
|
//
|
|
// 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.
|
|
|
|
// Package mp3 provides MP3 decoder.
|
|
//
|
|
// On desktops and mobiles, a pure Go decoder is used.
|
|
// On browsers, a native decoder on the browser is used.
|
|
package mp3
|
|
|
|
import (
|
|
"io"
|
|
|
|
"github.com/hajimehoshi/go-mp3"
|
|
|
|
"github.com/hajimehoshi/ebiten/v2/audio"
|
|
"github.com/hajimehoshi/ebiten/v2/audio/internal/convert"
|
|
)
|
|
|
|
// Stream is a decoded stream.
|
|
type Stream struct {
|
|
orig *mp3.Decoder
|
|
resampling *convert.Resampling
|
|
}
|
|
|
|
// Read is implementation of io.Reader's Read.
|
|
func (s *Stream) Read(buf []byte) (int, error) {
|
|
if s.resampling != nil {
|
|
return s.resampling.Read(buf)
|
|
}
|
|
return s.orig.Read(buf)
|
|
}
|
|
|
|
// Seek is implementation of io.Seeker's Seek.
|
|
func (s *Stream) Seek(offset int64, whence int) (int64, error) {
|
|
if s.resampling != nil {
|
|
return s.resampling.Seek(offset, whence)
|
|
}
|
|
return s.orig.Seek(offset, whence)
|
|
}
|
|
|
|
// Length returns the size of decoded stream in bytes.
|
|
func (s *Stream) Length() int64 {
|
|
if s.resampling != nil {
|
|
return s.resampling.Length()
|
|
}
|
|
return s.orig.Length()
|
|
}
|
|
|
|
// DecodeWithSampleRate decodes MP3 source and returns a decoded stream.
|
|
//
|
|
// DecodeWithSampleRate returns error when decoding fails or IO error happens.
|
|
//
|
|
// DecodeWithSampleRate automatically resamples the stream to fit with sampleRate if necessary.
|
|
//
|
|
// A Stream doesn't close src even if src implements io.Closer.
|
|
// Closing the source is src owner's responsibility.
|
|
func DecodeWithSampleRate(sampleRate int, src io.ReadSeeker) (*Stream, error) {
|
|
d, err := mp3.NewDecoder(src)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
var r *convert.Resampling
|
|
if d.SampleRate() != sampleRate {
|
|
r = convert.NewResampling(d, d.Length(), d.SampleRate(), sampleRate)
|
|
}
|
|
s := &Stream{
|
|
orig: d,
|
|
resampling: r,
|
|
}
|
|
return s, nil
|
|
}
|
|
|
|
// Decode decodes MP3 source and returns a decoded stream.
|
|
//
|
|
// Decode returns error when decoding fails or IO error happens.
|
|
//
|
|
// Decode automatically resamples the stream to fit with the audio context if necessary.
|
|
//
|
|
// A Stream doesn't close src even if src implements io.Closer.
|
|
// Closing the source is src owner's responsibility.
|
|
//
|
|
// Deprecated: as of v2.1. Use DecodeWithSampleRate instead.
|
|
func Decode(context *audio.Context, src io.ReadSeeker) (*Stream, error) {
|
|
return DecodeWithSampleRate(context.SampleRate(), src)
|
|
}
|