From 8c2064c8b73448e2932811eb66c17dfdf237e034 Mon Sep 17 00:00:00 2001 From: Hajime Hoshi Date: Sun, 22 Jan 2017 19:43:03 +0900 Subject: [PATCH] audio: Apply delaying when initializing --- audio/internal/driver/driver_js.go | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/audio/internal/driver/driver_js.go b/audio/internal/driver/driver_js.go index c4410bc0d..5333c8894 100644 --- a/audio/internal/driver/driver_js.go +++ b/audio/internal/driver/driver_js.go @@ -23,6 +23,11 @@ import ( "github.com/gopherjs/gopherjs/js" ) +// positionDelay is buffer in sample numbers for p.positionInSamples. +// Without this, adjusting p.positionInSamples with the context's currenTime +// much more often especially on Safari, which is the cause of noise (#307). +const positionDelay = 256 + type Player struct { sampleRate int channelNum int @@ -73,10 +78,10 @@ func NewPlayer(sampleRate, channelNum, bytesPerSample int) (*Player, error) { // domain page in an iframe. p.context.Call("resume") p.context.Call("createBufferSource").Call("start", 0) - p.positionInSamples = int64(p.context.Get("currentTime").Float() * float64(p.sampleRate)) + p.positionInSamples = int64(p.context.Get("currentTime").Float()*float64(p.sampleRate)) + positionDelay }) } - p.positionInSamples = int64(p.context.Get("currentTime").Float() * float64(p.sampleRate)) + p.positionInSamples = int64(p.context.Get("currentTime").Float()*float64(p.sampleRate)) + positionDelay return p, nil } @@ -91,13 +96,9 @@ func toLR(data []byte) ([]int16, []int16) { } func (p *Player) Proceed(data []byte) error { - // delay is buffer in sample numbers for p.positionInSamples. - // Without this, adjusting p.positionInSamples with the context's currenTime - // much more often especially on Safari, which is the cause of noise (#307). - const delay = 256 p.bufferedData = append(p.bufferedData, data...) c := int64(p.context.Get("currentTime").Float() * float64(p.sampleRate)) - if p.positionInSamples+delay < c { + if p.positionInSamples+positionDelay < c { p.positionInSamples = c } // Heuristic data size which doesn't cause too much noise and too much delay (#299) @@ -118,7 +119,7 @@ func (p *Player) Proceed(data []byte) error { s := p.context.Call("createBufferSource") s.Set("buffer", buf) s.Call("connect", p.context.Get("destination")) - s.Call("start", float64(p.positionInSamples+delay)/float64(p.sampleRate)) + s.Call("start", float64(p.positionInSamples+positionDelay)/float64(p.sampleRate)) p.positionInSamples += int64(len(il)) p.bufferedData = p.bufferedData[dataSize:] }