MAGIC_DOT_BYTE
if (data[MAGIC_DOT_BYTE] != 0x00) {
state->idx = data[MAGIC_DOT_BYTE] ^ state->carry;
data[MAGIC_DOT_BYTE] ^= state->carry;
#define MAGIC_BYTE_OFF(x) (((x) * BYTE_PER_SAMPLE) + MAGIC_DOT_BYTE)