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Re: problem writing OS X audio driver
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Re: problem writing OS X audio driver


  • Subject: Re: problem writing OS X audio driver
  • From: Laurent Humbert <email@hidden>
  • Date: Fri, 21 Jun 2002 14:38:02 +0200

At 1:49 AM -0400 6/21/02, Herbie Robinson wrote:

Is it possible that only the low order bytes need swapping (this seems extremely unlikely)?

Thanks for the suggestion, I tried that but to no avail...

MyAudioEngine::convertInputSamples method looks like this:

This is not a functional problem, but the following:

*floatDestBuf = (*inputBuf << 8) / 2147483648.0;

Can be improved performance-wise by multiplying by the constant (2**-31). Multiplies are usually around 100 times faster than divides on a RISC machine (and more than 10 times faster on CISC machines). The compiler might fix this for you, but why take a chance.

Yes I know it probably not very efficient, but I'll have a close look at optimizations later in the development process when I have a first beta.

Thanks;

L
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References: 
 >problem writing OS X audio driver (From: Laurent Humbert <email@hidden>)
 >Re: problem writing OS X audio driver (From: Herbie Robinson <email@hidden>)

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