Converting a 8 bit PCM to 16 bit PCM

Question

Starting from this question I was made to understand how to deinterleave the left and right channel of a 16 bit PCM data.

My question now is, how will a 8 bit PCM be deinterleaved and "stretched" into a 16 bit value

Answer 1

16-bit PCM has basically the same data bits and additional bits on the least significant bit side to specify the value and add accuracy and detail. Then 8-bit PCM is typically unsigned value with a centerpoint of 0x80, and 16-bit (also applicable to higher bitnesses) PCM is signed integer, so the conversion formula is:

UINT8 sample8 = ...;
INT16 sample16 = (INT16) (sample8 - 0x80) << 8;