Re: what type for 24bit
Re: what type for 24bit
- Subject: Re: what type for 24bit
- From: Kurt Bigler <email@hidden>
- Date: Fri, 23 May 2003 15:23:29 -0700
on 5/23/03 1:29 PM, Mark's Studio <email@hidden> wrote:
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Im making a Cocoa sound editor, and im working on the soundfile part of
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it,
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8 bit = SInt8
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16 bit = SInt16
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32 bit = Float32
32 bit might be SInt32, depending on the format. The "32-bit" data is often
really 24-bit but padded to 32-bits for simpler access.
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But what is used for 24 bit?
Use a UInt8 pointer to move 3 successive bytes into or out of an SInt32
variable which you use to hold 24-bits that are of interest to you.
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I was also thinking about converting the soundfile to Float32 when
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opened for editing,
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and then converted back to the original format when saved.
Depending on what processing you are doing in your "editing" you might even
want to use Float64 sometimes. Some kinds of filter implementations will
have problems with Float32. You have to go study up on the DSP stuff.
Doing much in the way of DSP in integer variables can be very difficult and
most people will use floats to avoid much hair-pulling.
If you are doing calculations in batch mode as opposed to real-time, then
you might want to just use Float64 for all everything except when you write
out to the file. This will be a bit slower, but will work well for
everything. You could try Float32 everywhere if your filtering needs are
simple enough.
-Kurt Bigler
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What are the pros./cons.
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Peter Mark
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Mark's Recording Studio A/S
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Lundeskovsvej 3 2900 Hellerup
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Denmark
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Tel: +45 35366078 Fax: +45 35366038
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www.marks-studio.dk
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email@hidden
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