Bug 122560 – scriptProcessor Node not working on iOS (Safari/Chrome)

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Audio

[Leinho]

Created attachment 213792 [details]
Code of my app where scriptProcessor Node is not working on iOS

I have created an app in HTML 5 that generates white noise on its own using a ScriptProcessorNode (Google Chrome) or a JavaScriptNode (Safari).
All is working fine for Google Chrome/Safari on my Mac and also in my Android phone but it is not working in Safari/Chrome on my iPod Touch 5th/iPad 4th on iOS 6.1.2. 

Browsers checked:

iOS:
Mob Safari 6.0 (Not working) (536.26 WebKit)
Chrome Mob iOS 30.0.1.1599 (Not working) (536.26 WebKit)
Mob Safari 7.0 (Not working)

MAC:
Desktop Chrome 30.0.1599 on MAC (Working) (537.36 WebKit)
Desktop Safari 6.0.5 on Mac (Working) (536.30.1 WebKit)

Android: 

Chrome 29.0.1547.59 1547059 (Working) (WebKit 537.36)

I have a button on the screen that when it is touched the gainNode is connected to context.destination or it's disconnected. I can see that onaudioprocess event is not triggered on my iPod (iOS 6.1.2 Safari and Chrome)...
 
I am attaching the code of my simple app.
 
What am I doing wrong? Is something different from Safari/Chrome on iOS than for MAC that I am not considering?
 
I need to create sound samples on the fly... If this work I would add a filter node to filter the white noise for generating other sounds as the user wants.

Thanks!

[Jer Noble]

iOS Safari has an additional restriction that desktop Safari (and Chrome/Android) do not:

The audio context must be created in response to a user event.

If you restructure your code so that init() is called from within Start_Audio(), the sample works fine.

[Leinho]

I have tried what you said but still with no success. I am attaching my new code that is not working on iOS yet. I have tested it on iOS 6.1.2 (Safari and Chrome)...

By the way, I have found this web: http://compatibility.shwups-cms.ch/en/home?

In this link I see that scripProcessor isn't supported on Chrome or Safari. I am using JavaScriptNode in case scriptProcessor isn't supported but still not working on iOS 6. Is that site trustable?

What are you using as platform?

Thanks!




(In reply to comment #1)
> iOS Safari has an additional restriction that desktop Safari (and Chrome/Android) do not:
> 
> The audio context must be created in response to a user event.
> 
> If you restructure your code so that init() is called from within Start_Audio(), the sample works fine.

[Leinho]

Created attachment 213982 [details]
Added another button that must be touched before play/stop button. It is used to initialise the objects including the audioContext.

[Leinho]

Comment on attachment 213982 [details]
Added another button that must be touched before play/stop button. It is used to initialise the objects including the audioContext.

I can not hear anything yet on iOS 6.1.2

[Leinho]

Comment on attachment 213982 [details]
Added another button that must be touched before play/stop button. It is used to initialise the objects including the audioContext.

I can not hear anything yet on iOS 6.1.2

[Leinho]

Also, this code is working on iOS 6.1.2, both browsers, and the audioContext is created in onLoad... I am looping on an audioBuffer using audioBufferSource node.

The code I mentioned is attached as: "audiocontext initialised in onLoad method".


(In reply to comment #2)
> I have tried what you said but still with no success. I am attaching my new code that is not working on iOS yet. I have tested it on iOS 6.1.2 (Safari and Chrome)...
> 
> By the way, I have found this web: http://compatibility.shwups-cms.ch/en/home?
> 
> In this link I see that scripProcessor isn't supported on Chrome or Safari. I am using JavaScriptNode in case scriptProcessor isn't supported but still not working on iOS 6. Is that site trustable?
> 
> What are you using as platform?
> 
> Thanks!
> 
> 
> 
> 
> (In reply to comment #1)
> > iOS Safari has an additional restriction that desktop Safari (and Chrome/Android) do not:
> > 
> > The audio context must be created in response to a user event.
> > 
> > If you restructure your code so that init() is called from within Start_Audio(), the sample works fine.

[Leinho]

Created attachment 213987 [details]
Here I am initialising the context in the onLoad method. It is working using audioBufferSource class.

[Jer Noble]

(In reply to comment #2)
> By the way, I have found this web: http://compatibility.shwups-cms.ch/en/home?
> 
> In this link I see that scripProcessor isn't supported on Chrome or Safari. I am using JavaScriptNode in case scriptProcessor isn't supported but still not working on iOS 6. Is that site trustable?

That site is not trustworthy.

[Leinho]

Great to know that! Hope you can help me!

(In reply to comment #8)
> (In reply to comment #2)
> > By the way, I have found this web: http://compatibility.shwups-cms.ch/en/home?
> > 
> > In this link I see that scripProcessor isn't supported on Chrome or Safari. I am using JavaScriptNode in case scriptProcessor isn't supported but still not working on iOS 6. Is that site trustable?
> 
> That site is not trustworthy.

[Jer Noble]

There are still a number of problems with your example.  Namely, you have an assertion at line 33 of your most recent index.html, where setting 'context.sampleRate = 44100' fails because context is undefined.

You also need to recreate your AudioBufferSourceNode after calling stop(); each AudioBufferSourceNode can only be played once.  Please see the spec: <https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#AudioBufferSourceNode>

You are still calling init() from window.onload, which is not a user event, so this code will still not work in Mobile Safari.  Try something like this:

    function Start_Audio()
    {
        if (!context)
            init();
    ...

		
And remove the 'window.onload = init' line.

[Leinho]

Sorry for missing to erase that line.

But, the last one (2013-10-11 06:55 PST) is working on Safari. This code was uploaded in order to show you that I can use the context on Safari without problems even declaring in the onLoad method.

The one that I uploaded at 2013-10-11 05:21 PST is the update of my first version where I added another button to initialise the context. It is not working on iOS...

Thanks for the AudioBufferSourceNode advise, I knew it but I didn't solve it because that is another step in my development.



(In reply to comment #10)
> There are still a number of problems with your example.  Namely, you have an assertion at line 33 of your most recent index.html, where setting 'context.sampleRate = 44100' fails because context is undefined.
> 
> You also need to recreate your AudioBufferSourceNode after calling stop(); each AudioBufferSourceNode can only be played once.  Please see the spec: <https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#AudioBufferSourceNode>
> 
> You are still calling init() from window.onload, which is not a user event, so this code will still not work in Mobile Safari.  Try something like this:
> 
>     function Start_Audio()
>     {
>         if (!context)
>             init();
>     ...
> 
> 
> And remove the 'window.onload = init' line.

[Leinho]

Thanks Jer Noble, It's working on iOS 7 now with the suggestion you made. It's a pity that it can not work on iOS 6. 

It can be noted that an upgrade was made to web audio api compliance on iOS 7 as a scriptProcessor Node can be used.

Thanks you very much!

(In reply to comment #11)
> Sorry for missing to erase that line.
> 
> But, the last one (2013-10-11 06:55 PST) is working on Safari. This code was uploaded in order to show you that I can use the context on Safari without problems even declaring in the onLoad method.
> 
> The one that I uploaded at 2013-10-11 05:21 PST is the update of my first version where I added another button to initialise the context. It is not working on iOS...
> 
> Thanks for the AudioBufferSourceNode advise, I knew it but I didn't solve it because that is another step in my development.
> 
> 
> 
> (In reply to comment #10)
> > There are still a number of problems with your example.  Namely, you have an assertion at line 33 of your most recent index.html, where setting 'context.sampleRate = 44100' fails because context is undefined.
> > 
> > You also need to recreate your AudioBufferSourceNode after calling stop(); each AudioBufferSourceNode can only be played once.  Please see the spec: <https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#AudioBufferSourceNode>
> > 
> > You are still calling init() from window.onload, which is not a user event, so this code will still not work in Mobile Safari.  Try something like this:
> > 
> >     function Start_Audio()
> >     {
> >         if (!context)
> >             init();
> >     ...
> > 
> > 
> > And remove the 'window.onload = init' line.