[Webkit-unassigned] [Bug 77609] New: AudioBus need to support stereo->mono down mix in copyFrom sumFrom etc.

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=77609

           Summary: AudioBus need to support stereo->mono down mix in
                    copyFrom sumFrom etc.
           Product: WebKit
           Version: 528+ (Nightly build)
          Platform: Unspecified
        OS/Version: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: Web Audio
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: rgbbones at gmail.com
                CC: crogers at google.com


Hi

Usually this is not a big issue. But in the situation that :

A OfflineContext with mono channel buffer is connected to a RealtimeAnalyserNode, things go bad. Since RealtimeAnalyserNode is hardcoded to stereo, in the debug mode, this will lead to crash by ASSERT in AudioBuscopyFrom. And the best case is in release mode, it just return, thus no music is outputed. And this could also happen for other nodes if source and destination's channels not match.

But in this very case, the user might never know what is going on, for even the source buffer is mono, offlineContext buffer is mono, it still go wrong, he will never know that realtimeAnalyserNode rune everything.

I think the solution is :

1. make RealtimeAnalyserNode more clever and can adjust its output channel to suit for input channel
2. support down mix in audioBus

2 is a must. while 1 might be a addon.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.