[Openal] Distortion when pitch-shifting under win32

[Daniel PEACOCK]

Hi,

Knowing the OpenAL device that is being used would be very helpful.   After
you have successfully initialized OpenAL, you can call
alcGetString(pDeviceHandle, ALC_DEVICE_SPECIFIER) to retrieve the name of
the opened device.   Are you setting any of the following parameters ... ?

Source Velocity
Source Pitch
Listener Velocity
Doppler Factor
Doppler Velocity (now deprecated)
Speed of Sound

Thanks,

Dan

Notice
The information in this message is confidential and may be legally
privileged.  It is intended solely for the addressee.  Access to this
message by anyone else is unauthorized.  If you are not the intended
recipient,  any disclosure,  copying or distribution of the message,  or
any action taken by you in reliance on it,  is prohibited and may be
unlawful.  If you have received this message in error,  please delete it
and contact the sender immediately.  Thank you.



                                                                           
             Nolan Darilek                                                 
             <nolan at thewordner                                             
             d.info>                                                    To 
             Sent by:                  openal at opensource.creative.com      
             openal-bounces at op                                          cc 
             ensource.creative                                             
             .com                                                  Subject 
                                       [Openal] Distortion when            
                                       pitch-shifting under win32          
             01/30/2007 10:37                                              
             AM                                                            
                                                                           
                                                                           
                                                                           
                                                                           




Hello. I've been having an annoying OpenAL issue under win32 only,
and I'm hoping there's a solution for it. Whenever I pitch-shift
audio, the audio distorts, almost as if it's clipping. This seems to
happen regardless of velocity, and even for sounds whose volumes are
very quiet (0.1.) I realize that this is a somewhat meaningless
number, but as it doesn't happen a) when the sound isn't pitch-
shifted or b) under Linux running the exact same hardware, I suspect
a win32 issue. Other than that, things seem to be working nicely.

A bit more about my setup: I'm using Java/LWJGL's OpenAL bindings.
These shipped with OpenAL 1.0, but I've also copied in the 1.1 DLLs
downloaded as of last December or so with the same results. I'm not
initializing a specific backend, which I assume initializes some
reasonable platform default as it provides nice 5.1 audio under the
standard OS X Tiger implementation and stereo under Linux. I assume
this selects DirectSound3D under win32, but I've not confirmed this,
and if it would help knowing, I'd be happy to find out provided
someone tells me how.

This seems to be the one remaining issue for me, and I'm eager to
resolve it. Oh, it also happens with multiple sounds, leading me to
furter suspect that it's a library issue and not GIGO. :) Has anyone
else seen this?

_______________________________________________
Openal mailing list
Openal at opensource.creative.com
http://opensource.creative.com/mailman/listinfo/openal

ForwardSourceID:NT0003BEA6