data: a string (values between 0 and 255) that contains packed int32 numbers
startInt32Index: the zero-based index from which on data should be unpacked (from data[4*startInt32Index+1+additionalByteOffset]). Can be omitted in which case 0 is used
int32Count: the amount of int32s that should be unpacked. Can be omitted in which case 0 is used (which indicates that the maximum of int32s should be unpacked from the indicated startInt32Index)
additionalByteOffset: a byte offset that will be added before reading the int32s. Can be omitted, in which case 0 is used.