static int parse_dmix_coeffs(struct xll_chset *chs)
{
struct xll_decoder *xll = chs->decoder;
int m, n;
if (chs->primary_chset) {
m = dmix_primary_nch[chs->dmix_type];
n = chs->nchannels;
} else {
m = chs->dmix_m;
n = chs->nchannels + 2; // Two extra columns for scales
}
// Reallocate downmix coefficients matrix
if (ta_zalloc_fast(xll->chset, &chs->dmix_coeff, m * n, sizeof(int)) < 0)
return -DCADEC_ENOMEM;
if (chs->primary_chset) {
chs->dmix_scale = NULL;
chs->dmix_scale_inv = NULL;
} else {
chs->dmix_scale = chs->dmix_coeff + m * chs->nchannels;
chs->dmix_scale_inv = chs->dmix_coeff + m * (chs->nchannels + 1);
}
int *coeff_ptr = chs->dmix_coeff;
for (int i = 0; i < m; i++) {
int scale_inv = 0;
// Downmix scale
// Only for non-primary channel sets
if (!chs->primary_chset) {
int code = bits_get(&xll->bits, 9);
int sign = (code >> 8) - 1; code &= 0xff;
if (code > 0) {
unsigned int index = code - 1;
enforce(index >= 40 && index < dca_countof(dmix_table), "Invalid downmix scale index");
int scale = dmix_table[index];
scale_inv = dmix_table_inv[index - 40];
chs->dmix_scale[i] = (scale ^ sign) - sign;
chs->dmix_scale_inv[i] = (scale_inv ^ sign) - sign;
} else {
chs->dmix_scale[i] = 0;
chs->dmix_scale_inv[i] = 0;
}
}
// Downmix coefficients
for (int j = 0; j < chs->nchannels; j++) {
int code = bits_get(&xll->bits, 9);
int sign = (code >> 8) - 1; code &= 0xff;
if (code > 0) {
unsigned int index = code - 1;
enforce(index < dca_countof(dmix_table), "Invalid downmix coefficient index");
int coeff = dmix_table[index];
if (!chs->primary_chset)
// Multiply by |InvDmixScale| to get |UndoDmixScale|
coeff = mul16(scale_inv, coeff);
// Convert sign
*coeff_ptr++ = (coeff ^ sign) - sign;
} else {
*coeff_ptr++ = 0;
}
}
}
static int parse_dmix_coeffs(struct xll_chset *chs)
{
struct xll_decoder *xll = chs->decoder;
int m, n;
if (chs->primary_chset) {
m = dmix_primary_nch[chs->dmix_type];
n = chs->nchannels;
} else {
m = chs->dmix_m;
n = chs->nchannels + 2; // Two extra columns for scales
}
// Reallocate downmix coefficients buffer
if (ta_zalloc_fast(xll->chset, &chs->dmix_coeff, m * n * 2, sizeof(int)) < 0)
return -DCADEC_ENOMEM;
// Setup buffer pointers for current and previous frame
bool valid = (chs->dmix_coeffs_signature == XLL_DMIX_SIGNATURE(chs));
chs->dmix_coeff_cur = chs->dmix_coeff + m * n * chs->dmix_coeffs_parity;
chs->dmix_coeff_pre = chs->dmix_coeff + m * n * (chs->dmix_coeffs_parity ^ valid);
if (chs->primary_chset) {
chs->dmix_scale_cur = chs->dmix_scale_pre = NULL;
chs->dmix_scale_inv_cur = chs->dmix_scale_inv_pre = NULL;
} else {
chs->dmix_scale_cur = chs->dmix_coeff_cur + m * chs->nchannels;
chs->dmix_scale_pre = chs->dmix_coeff_pre + m * chs->nchannels;
chs->dmix_scale_inv_cur = chs->dmix_coeff_cur + m * (chs->nchannels + 1);
chs->dmix_scale_inv_pre = chs->dmix_coeff_pre + m * (chs->nchannels + 1);
}
int *coeff_ptr = chs->dmix_coeff_cur;
for (int i = 0; i < m; i++) {
int scale_inv = 0;
// Downmix scale
// Only for non-primary channel sets
if (!chs->primary_chset) {
int code = bits_get(&xll->bits, 9);
int sign = (code >> 8) - 1; code &= 0xff;
if (code > 0) {
unsigned int index = code - 1;
if (index < 40 || index >= dca_countof(dmix_table)) {
xll_err("Invalid downmix scale index");
return -DCADEC_EBADDATA;
}
int scale = dmix_table[index];
scale_inv = dmix_table_inv[index - 40];
chs->dmix_scale_cur[i] = (scale ^ sign) - sign;
chs->dmix_scale_inv_cur[i] = (scale_inv ^ sign) - sign;
} else {
chs->dmix_scale_cur[i] = 0;
chs->dmix_scale_inv_cur[i] = 0;
}
}
// Downmix coefficients
for (int j = 0; j < chs->nchannels; j++) {
int code = bits_get(&xll->bits, 9);
int sign = (code >> 8) - 1; code &= 0xff;
if (code > 0) {
unsigned int index = code - 1;
if (index >= dca_countof(dmix_table)) {
xll_err("Invalid downmix coefficient index");
return -DCADEC_EBADDATA;
}
int coeff = dmix_table[index];
if (!chs->primary_chset)
// Multiply by |InvDmixScale| to get |UndoDmixScale|
coeff = mul16(scale_inv, coeff);
// Convert sign
*coeff_ptr++ = (coeff ^ sign) - sign;
} else {
*coeff_ptr++ = 0;
}
}
}
