data: a string (values between 0 and 255) that contains packed uint16 numbers
starUint16Index: the zero-based index from which on data should be unpacked (from data[2*starUint16Index+1+additionalByteOffset]). Can be omitted in which case 0 is used.
uint16Count: the amount of uint16s that should be unpacked. Can be omitted in which case 0 is used (which indicates that the maximum of uint16s should be unpacked from the indicated starUint16Index).
additionalByteOffset: a byte offset that will be added before reading the uint16s. Can be omitted, in which case 0 is used.