static int qoa_lms_predict(qoa_lms_t *lms) {
int prediction = 0;
for (int i = 0; i < QOA_LMS_LEN; i++) {
prediction += lms->weights[i] * lms->history[i];
}
return prediction >> 13;
}

static void qoa_lms_update(qoa_lms_t *lms, int sample, int residual) {
int delta = residual >> 4;
for (int i = 0; i < QOA_LMS_LEN; i++) {
lms->weights[i] += lms->history[i] < 0 ? -delta : delta;
}

for (int i = 0; i < QOA_LMS_LEN-1; i++) {
lms->history[i] = lms->history[i+1];
}
lms->history[QOA_LMS_LEN-1] = sample;
}