Subj : Converting 2 chars (bytes) to a short
To   : All
From : Nightfox
Date : Thu Jun 02 2011 09:18 am

In C or C++, suppose there is an array of 2 chars:
char charArray[2];

If one wanted to convert those 2 char values to a short, I can think of 2 ways
to do it:
- Method 1 - Bit shifting and ORing:
short shortVal = ((charArray[1] << 8) | charArray[0]);
- Another way I've tried this:
short shortVal = (short)(charArray[1]);
shortVal <<= 8;
shortVal |= charArray[0];

- Method 2 - Using memcpy():
short shortVal = 0;
memcpy((void*)&shortVal, (void*)charArray, 2);

Is either way any better than the other?  And does the bit-shift & OR method
look fine?  I'm asking because I'm working on some C++ code for reading &
writing WAV files, and when using the bit-shift/OR method to read 16-bit audio
samples, the audio sounds a bit distorted, but using the memcpy() method, it
sounds fine.  I'm not sure why that is, unless I'm not bit-shifting or ORing
correctly in the first method..

Nightfox

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