Use of type 'short'
The current version of Opus (from git) seems to use 'short' as type for audio data.
The type 'short' is not defined to have a fixed size (I have seen 1..4 bytes in wild yet). This may cause problems. It is not unlikely the size to be not 16 bit on embedded systems. This may harm availability and adaption on such devices.
Please consider changing use of native types to types from <stdint.h> or similar or explain why short is correct (in the header) and how to handle cases with sizeof(short) != 2 correctly.