Re: [ecasound] lossless conversion broken?

From: Kai Vehmanen <kvehmanen@email-addr-hidden>
Date: Thu Nov 04 2010 - 23:02:45 EET


On Wed, 3 Nov 2010, Dan Muresan wrote:

> I looked at the code. I'm surprised at a different asymmetry -- the
> one between eca_sample_convert_float_to_s32 vs.
> eca_sample_convert_s32_to_float:
> int32_t eca_sample_convert_float_to_s32(float inval) {
> if (inval < 0.0f)
> return((int32_t)((float)(inval * (INT32_MAX))));
> return((int32_t)((float)(inval * INT32_MAX) - 0.5f));
> }

oh yes, thanks, I've been blind to that completely, that's not right at
all. Definitely a bug. It sure is depressing to find such stuff... :P

> I agree with the jackit threads -- introducing a nonlinear
> transformation in a chain is not a good thing (from a signals &
> systems POV). Sounds like 0x8000, symmetrical would be best for the
> future. I assume this breaks existing files, which is why you'd have
> to wait for a major release.

Yes, agreed.

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Received on Fri Nov 5 00:15:03 2010

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