#define TNS_Q_BITS 4
/* Coefficient resolution in short windows */
-#define TNS_Q_BITS_IS8 4
+#define TNS_Q_BITS_IS8 3
-/* Define this to save a bit, be warned decoders can't deal with it
- * so it is not lossless despite what the specifications say */
-// #define TNS_ENABLE_COEF_COMPRESSION
+/* We really need the bits we save here elsewhere */
+#define TNS_ENABLE_COEF_COMPRESSION
/* TNS will only be used if the LPC gain is within these margins */
-#define TNS_GAIN_THRESHOLD_LOW 1.477f
-#define TNS_GAIN_THRESHOLD_HIGH 7.0f
-#define TNS_GAIN_THRESHOLD_LOW_IS8 0.16f*TNS_GAIN_THRESHOLD_LOW
-#define TNS_GAIN_THRESHOLD_HIGH_IS8 0.26f*TNS_GAIN_THRESHOLD_HIGH
+#define TNS_GAIN_THRESHOLD_LOW 1.4f
+#define TNS_GAIN_THRESHOLD_HIGH 1.16f*TNS_GAIN_THRESHOLD_LOW
static inline int compress_coeffs(int *coef, int order, int c_bits)
{
*/
void ff_aac_encode_tns_info(AACEncContext *s, SingleChannelElement *sce)
{
- int i, w, filt, coef_compress = 0, coef_len;
TemporalNoiseShaping *tns = &sce->tns;
+ int i, w, filt, coef_compress = 0, coef_len;
const int is8 = sce->ics.window_sequence[0] == EIGHT_SHORT_SEQUENCE;
const int c_bits = is8 ? TNS_Q_BITS_IS8 == 4 : TNS_Q_BITS == 4;
int i;
const float *quant_arr = tns_tmp2_map[c_bits];
for (i = 0; i < order; i++) {
- idx[i] = quant_array_idx((float)coef[i], quant_arr, c_bits ? 16 : 8);
+ idx[i] = quant_array_idx(coef[i], quant_arr, c_bits ? 16 : 8);
lpc[i] = quant_arr[idx[i]];
}
}
void ff_aac_search_for_tns(AACEncContext *s, SingleChannelElement *sce)
{
TemporalNoiseShaping *tns = &sce->tns;
- double gain, coefs[MAX_LPC_ORDER];
int w, w2, g, count = 0;
+ double gain, coefs[MAX_LPC_ORDER];
const int mmm = FFMIN(sce->ics.tns_max_bands, sce->ics.max_sfb);
const int is8 = sce->ics.window_sequence[0] == EIGHT_SHORT_SEQUENCE;
const int c_bits = is8 ? TNS_Q_BITS_IS8 == 4 : TNS_Q_BITS == 4;
+ const int sfb_start = av_clip(tns_min_sfb[is8][s->samplerate_index], 0, mmm);
+ const int sfb_end = av_clip(sce->ics.num_swb, 0, mmm);
+ const int order = is8 ? 7 : s->profile == FF_PROFILE_AAC_LOW ? 12 : TNS_MAX_ORDER;
const int slant = sce->ics.window_sequence[0] == LONG_STOP_SEQUENCE ? 1 :
sce->ics.window_sequence[0] == LONG_START_SEQUENCE ? 0 : 2;
- int sfb_start = av_clip(tns_min_sfb[is8][s->samplerate_index], 0, mmm);
- int sfb_end = av_clip(sce->ics.num_swb, 0, mmm);
- int order = is8 ? 5 : s->profile == FF_PROFILE_AAC_LOW ? 12 : TNS_MAX_ORDER;
-
for (w = 0; w < sce->ics.num_windows; w++) {
float en[2] = {0.0f, 0.0f};
+ int oc_start = 0, os_start = 0;
int coef_start = w*sce->ics.num_swb + sce->ics.swb_offset[sfb_start];
int coef_len = sce->ics.swb_offset[sfb_end] - sce->ics.swb_offset[sfb_start];
+ const int sfb_len = sfb_end - sfb_start;
for (g = 0; g < sce->ics.num_swb; g++) {
if (w*16+g < sfb_start || w*16+g > sfb_end)
continue;
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
- if ((w+w2)*16+g > sfb_start + ((sfb_end - sfb_start)/2))
+ if ((w+w2)*16+g > sfb_start + (sfb_len/2))
en[1] += band->energy;
else
en[0] += band->energy;
}
}
- if (coef_len <= 0 || (sfb_end - sfb_start) <= 0)
+ if (coef_len <= 0 || sfb_len <= 0)
continue;
/* LPC */
if (!order || gain < TNS_GAIN_THRESHOLD_LOW || gain > TNS_GAIN_THRESHOLD_HIGH)
continue;
- if (is8 && (gain < TNS_GAIN_THRESHOLD_LOW_IS8 || gain > TNS_GAIN_THRESHOLD_HIGH_IS8))
- continue;
- if (is8 || order < 2) {
- tns->n_filt[w] = 1;
- for (g = 0; g < tns->n_filt[w]; g++) {
- tns->length[w][g] = sfb_end - sfb_start;
- tns->direction[w][g] = slant != 2 ? slant : en[0] < en[1];
- tns->order[w][g] = order;
- quantize_coefs(coefs, tns->coef_idx[w][g], tns->coef[w][g],
- order, c_bits);
- }
- } else { /* 2 filters due to energy disbalance */
- tns->n_filt[w] = 2;
- for (g = 0; g < tns->n_filt[w]; g++) {
- tns->direction[w][g] = slant != 2 ? slant : en[g] < en[!g];
- tns->order[w][g] = !g ? order/2 : order - tns->order[w][g-1];
- tns->length[w][g] = !g ? (sfb_end - sfb_start)/2 : \
- (sfb_end - sfb_start) - tns->length[w][g-1];
- quantize_coefs(&coefs[!g ? 0 : order - tns->order[w][g-1]],
- tns->coef_idx[w][g], tns->coef[w][g],
- tns->order[w][g], c_bits);
- }
+
+ tns->n_filt[w] = is8 ? 1 : order != TNS_MAX_ORDER ? 2 : 3;
+ for (g = 0; g < tns->n_filt[w]; g++) {
+ tns->direction[w][g] = slant != 2 ? slant : en[g] < en[!g];
+ tns->order[w][g] = g < tns->n_filt[w] ? order/tns->n_filt[w] : order - oc_start;
+ tns->length[w][g] = g < tns->n_filt[w] ? sfb_len/tns->n_filt[w] : sfb_len - os_start;
+ quantize_coefs(&coefs[oc_start], tns->coef_idx[w][g], tns->coef[w][g],
+ tns->order[w][g], c_bits);
+ oc_start += tns->order[w][g];
+ os_start += tns->length[w][g];
}
- count += tns->n_filt[w];
+ count++;
}
sce->tns.present = !!count;
}
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