int center_mix_level; ///< Center mix level index
int surround_mix_level; ///< Surround mix level index
float downmix_coeffs[AC3_MAX_CHANNELS][2]; ///< stereo downmix coefficients
+ float downmix_coeff_sum[2]; ///< sum of downmix coeffs for each output channel
float dynamic_range[2]; ///< dynamic range
int cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates
int num_cpl_bands; ///< number of coupling bands
int nf = s->channel_mode - 4;
s->downmix_coeffs[nf][0] = s->downmix_coeffs[nf+1][1] = smix;
}
+
+ s->downmix_coeff_sum[0] = s->downmix_coeff_sum[1] = 0.0f;
+ for(i=0; i<s->fbw_channels; i++) {
+ s->downmix_coeff_sum[0] += s->downmix_coeffs[i][0];
+ s->downmix_coeff_sum[1] += s->downmix_coeffs[i][1];
+ }
}
/**
static void ac3_downmix(AC3DecodeContext *s)
{
int i, j;
- float v0, v1, s0, s1;
+ float v0, v1;
for(i=0; i<256; i++) {
- v0 = v1 = s0 = s1 = 0.0f;
+ v0 = v1 = 0.0f;
for(j=0; j<s->fbw_channels; j++) {
v0 += s->output[j][i] * s->downmix_coeffs[j][0];
v1 += s->output[j][i] * s->downmix_coeffs[j][1];
- s0 += s->downmix_coeffs[j][0];
- s1 += s->downmix_coeffs[j][1];
}
- v0 /= s0;
- v1 /= s1;
+ v0 /= s->downmix_coeff_sum[0];
+ v1 /= s->downmix_coeff_sum[1];
if(s->output_mode == AC3_CHMODE_MONO) {
s->output[0][i] = (v0 + v1) * LEVEL_MINUS_3DB;
} else if(s->output_mode == AC3_CHMODE_STEREO) {