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Re: Playing wave file data
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Re: Playing wave file data


  • Subject: Re: Playing wave file data
  • From: john <email@hidden>
  • Date: Wed, 15 Oct 2003 17:34:47 -0400

Just to add an unlikely possibility to look for...

I don't use the AudioFile API and rather implemented reading with my own methods. However, I ran into a bug of accessing the audio data not on the correct offset which made it massively distorted. However, as Steve mentioned it's amazing how much you can "mangle" the data and still make sense of it!

-- John


--- You don't mention anything about reading the header. You should read the header to determine whether the WAV file is 8-bit or 16-bit, mono or stereo. That could make a difference in sound quality.

--- Do you know that it's 16 bit sound?
--- I've never seen offset-binary used in a 16-bit WAV file (8-bits sometimes, yes).
--- IIRC, you use 16-bit WAV data as is (without arithmetic)

--- There *-IS-* some math behind this - don't just make up a number. If it's 16-bit sound, it has a range of -32768..+32767. So divide (using floating-point arithmetic) the sound integers by 32767 to get +/- 1.00000.

--- It's amazing how badly you can mangle the data and still hear what you're expecting (ears and brains are wonderful things - everybody should have some!).

That's symptomatic of high-bit-inversion. In your case, I'd bet on the high-bit being incorrectly inverted.

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Steve Bird
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References: 
 >Re: Playing wave file data (From: Steve Bird <email@hidden>)

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