#include "aacenc_utils.h"
#include "aacenc_quantization.h"
-static inline void conv_to_int32(int32_t *loc, float *samples, int num, float norm)
-{
- int i;
- for (i = 0; i < num; i++)
- loc[i] = ceilf((samples[i]/norm)*INT32_MAX);
-}
-
-static inline void conv_to_float(float *arr, int32_t *cof, int num)
-{
- int i;
- for (i = 0; i < num; i++)
- arr[i] = (float)cof[i]/INT32_MAX;
-}
-
-/* Input: quantized 4 bit coef, output: 1 if first (MSB) 2 bits are the same */
-static inline int coef_test_compression(int coef)
-{
- int tmp = coef >> 2;
- int res = ff_ctz(tmp);
- if (res > 1)
- return 1; /* ...00 -> compressable */
- else if (res == 1)
- return 0; /* ...10 -> uncompressable */
- else if (ff_ctz(tmp >> 1) > 0)
- return 0; /* ...0 1 -> uncompressable */
- else
- return 1; /* ...1 1 -> compressable */
-}
-
-static inline int compress_coef(int *coefs, int num)
-{
- int i, res = 0;
- for (i = 0; i < num; i++)
- res += coef_test_compression(coefs[i]);
- return res == num ? 1 : 0;
-}
-
/**
* Encode TNS data.
- * Coefficient compression saves a single bit.
+ * Coefficient compression saves a single bit per coefficient.
*/
void ff_aac_encode_tns_info(AACEncContext *s, SingleChannelElement *sce)
{
- int i, w, filt, coef_len, coef_compress;
- const int coef_res = MAX_LPC_PRECISION == 4 ? 1 : 0;
+ uint8_t u_coef;
+ const uint8_t coef_res = TNS_Q_BITS == 4;
+ int i, w, filt, coef_len, coef_compress = 0;
const int is8 = sce->ics.window_sequence[0] == EIGHT_SHORT_SEQUENCE;
-
- put_bits(&s->pb, 1, !!sce->tns.present);
+ TemporalNoiseShaping *tns = &sce->tns;
if (!sce->tns.present)
return;
for (i = 0; i < sce->ics.num_windows; i++) {
put_bits(&s->pb, 2 - is8, sce->tns.n_filt[i]);
- if (sce->tns.n_filt[i]) {
- put_bits(&s->pb, 1, !!coef_res);
- for (filt = 0; filt < sce->tns.n_filt[i]; filt++) {
- put_bits(&s->pb, 6 - 2 * is8, sce->tns.length[i][filt]);
- put_bits(&s->pb, 5 - 2 * is8, sce->tns.order[i][filt]);
- if (sce->tns.order[i][filt]) {
- coef_compress = compress_coef(sce->tns.coef_idx[i][filt],
- sce->tns.order[i][filt]);
- put_bits(&s->pb, 1, !!sce->tns.direction[i][filt]);
+ if (tns->n_filt[i]) {
+ put_bits(&s->pb, 1, coef_res);
+ for (filt = 0; filt < tns->n_filt[i]; filt++) {
+ put_bits(&s->pb, 6 - 2 * is8, tns->length[i][filt]);
+ put_bits(&s->pb, 5 - 2 * is8, tns->order[i][filt]);
+ if (tns->order[i][filt]) {
+ put_bits(&s->pb, 1, !!tns->direction[i][filt]);
put_bits(&s->pb, 1, !!coef_compress);
coef_len = coef_res + 3 - coef_compress;
- for (w = 0; w < sce->tns.order[i][filt]; w++)
- put_bits(&s->pb, coef_len, sce->tns.coef_idx[i][filt][w]);
+ for (w = 0; w < tns->order[i][filt]; w++) {
+ u_coef = (tns->coef_idx[i][filt][w])&(~(~0<<coef_len));
+ put_bits(&s->pb, coef_len, u_coef);
+ }
}
}
}
}
}
-static int process_tns_coeffs(TemporalNoiseShaping *tns, float *tns_coefs_raw,
- int order, int w, int filt)
+static inline void quantize_coefs(double *coef, int *idx, float *lpc, int order)
{
- int i, j;
- int *idx = tns->coef_idx[w][filt];
- float *lpc = tns->coef[w][filt];
- const int iqfac_p = ((1 << (MAX_LPC_PRECISION-1)) - 0.5)/(M_PI/2.0);
- const int iqfac_m = ((1 << (MAX_LPC_PRECISION-1)) + 0.5)/(M_PI/2.0);
- float temp[TNS_MAX_ORDER] = {0.0f}, out[TNS_MAX_ORDER] = {0.0f};
-
- /* Quantization */
+ int i;
+ uint8_t u_coef;
+ const float *quant_arr = tns_tmp2_map[TNS_Q_BITS == 4];
+ const double iqfac_p = ((1 << (TNS_Q_BITS-1)) - 0.5)/(M_PI/2.0);
+ const double iqfac_m = ((1 << (TNS_Q_BITS-1)) + 0.5)/(M_PI/2.0);
for (i = 0; i < order; i++) {
- idx[i] = ceilf(asin(tns_coefs_raw[i])*((tns_coefs_raw[i] >= 0) ? iqfac_p : iqfac_m));
- lpc[i] = 2*sin(idx[i]/((idx[i] >= 0) ? iqfac_p : iqfac_m));
+ idx[i] = ceilf(asin(coef[i])*((coef[i] >= 0) ? iqfac_p : iqfac_m));
+ u_coef = (idx[i])&(~(~0<<TNS_Q_BITS));
+ lpc[i] = quant_arr[u_coef];
}
-
- /* Trim any coeff less than 0.1f from the end */
- for (i = order; i > -1; i--) {
- lpc[i] = (fabs(lpc[i]) > 0.1f) ? lpc[i] : 0.0f;
- if (lpc[i] != 0.0 ) {
- order = i;
- break;
- }
- }
-
- if (!order)
- return 0;
-
- /* Step up procedure, convert to LPC coeffs */
- out[0] = 1.0f;
- for (i = 1; i <= order; i++) {
- for (j = 1; j < i; j++) {
- temp[j] = out[j] + lpc[i]*out[i-j];
- }
- for (j = 1; j <= i; j++) {
- out[j] = temp[j];
- }
- out[i] = lpc[i-1];
- }
- memcpy(lpc, out, TNS_MAX_ORDER*sizeof(float));
-
- return order;
}
-static void apply_tns_filter(float *out, float *in, int order, int direction,
- float *tns_coefs, int ltp_used, int w, int filt,
- int start_i, int len)
+/* Apply TNS filter */
+void ff_aac_apply_tns(AACEncContext *s, SingleChannelElement *sce)
{
- int i, j, inc, start = start_i;
- float tmp[TNS_MAX_ORDER+1];
- if (direction) {
- inc = -1;
- start = (start + len) - 1;
- } else {
- inc = 1;
- }
- if (!ltp_used) { /* AR filter */
- for (i = 0; i < len; i++, start += inc)
- out[i] = in[start];
- for (j = 1; j <= FFMIN(i, order); j++)
- out[i] += tns_coefs[j]*in[start - j*inc];
- } else { /* MA filter */
- for (i = 0; i < len; i++, start += inc) {
- tmp[0] = out[i] = in[start];
- for (j = 1; j <= FFMIN(i, order); j++)
- out[i] += tmp[j]*tns_coefs[j];
- for (j = order; j > 0; j--)
- tmp[j] = tmp[j - 1];
+ TemporalNoiseShaping *tns = &sce->tns;
+ IndividualChannelStream *ics = &sce->ics;
+ int w, filt, m, i, top, order, bottom, start, end, size, inc;
+ const int mmm = FFMIN(ics->tns_max_bands, ics->max_sfb);
+ float lpc[TNS_MAX_ORDER];
+
+ for (w = 0; w < ics->num_windows; w++) {
+ bottom = ics->num_swb;
+ for (filt = 0; filt < tns->n_filt[w]; filt++) {
+ top = bottom;
+ bottom = FFMAX(0, top - tns->length[w][filt]);
+ order = tns->order[w][filt];
+ if (order == 0)
+ continue;
+
+ // tns_decode_coef
+ compute_lpc_coefs(tns->coef[w][filt], order, lpc, 0, 0, 0);
+
+ start = ics->swb_offset[FFMIN(bottom, mmm)];
+ end = ics->swb_offset[FFMIN( top, mmm)];
+ if ((size = end - start) <= 0)
+ continue;
+ if (tns->direction[w][filt]) {
+ inc = -1;
+ start = end - 1;
+ } else {
+ inc = 1;
+ }
+ start += w * 128;
+
+ // ar filter
+ for (m = 0; m < size; m++, start += inc)
+ for (i = 1; i <= FFMIN(m, order); i++)
+ sce->coeffs[start] += lpc[i-1]*sce->pcoeffs[start - i*inc];
}
}
}
void ff_aac_search_for_tns(AACEncContext *s, SingleChannelElement *sce)
{
TemporalNoiseShaping *tns = &sce->tns;
- int w, g, order, sfb_start, sfb_len, coef_start, shift[MAX_LPC_ORDER], count = 0;
+ int w, w2, g, count = 0;
+ 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 tns_max_order = is8 ? 7 : s->profile == FF_PROFILE_AAC_LOW ? 12 : TNS_MAX_ORDER;
- const float freq_mult = mpeg4audio_sample_rates[s->samplerate_index]/(1024.0f/sce->ics.num_windows)/2.0f;
- float max_coef = 0.0f;
+ const int order = is8 ? 7 : s->profile == FF_PROFILE_AAC_LOW ? 12 : TNS_MAX_ORDER;
- sce->tns.present = 0;
- return;
-
- for (coef_start = 0; coef_start < 1024; coef_start++)
- max_coef = FFMAX(max_coef, sce->pcoeffs[coef_start]);
+ 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);
for (w = 0; w < sce->ics.num_windows; w++) {
- int filters = 1, start = 0, coef_len = 0;
- int32_t conv_coeff[1024] = {0};
- int32_t coefs_t[MAX_LPC_ORDER][MAX_LPC_ORDER] = {{0}};
+ float e_ratio = 0.0f, threshold = 0.0f, spread = 0.0f, en[2] = {0.0, 0.0f};
+ double gain = 0.0f, coefs[MAX_LPC_ORDER] = {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];
- /* Determine start sfb + coef - excludes anything below threshold */
for (g = 0; g < sce->ics.num_swb; g++) {
- if (start*freq_mult > TNS_LOW_LIMIT) {
- sfb_start = w*16+g;
- sfb_len = (w+1)*16 + g - sfb_start;
- coef_start = sce->ics.swb_offset[sfb_start];
- coef_len = sce->ics.swb_offset[sfb_start + sfb_len] - coef_start;
- break;
+ 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))
+ en[1] += band->energy;
+ else
+ en[0] += band->energy;
+ threshold += band->threshold;
+ spread += band->spread;
}
- start += sce->ics.swb_sizes[g];
}
- if (coef_len <= 0)
+ if (coef_len <= 0 || (sfb_end - sfb_start) <= 0)
continue;
-
- conv_to_int32(conv_coeff, &sce->pcoeffs[coef_start], coef_len, max_coef);
+ else
+ e_ratio = en[0]/en[1];
/* LPC */
- order = ff_lpc_calc_coefs(&s->lpc, conv_coeff, coef_len,
- TNS_MIN_PRED_ORDER, tns_max_order,
- 32, coefs_t, shift,
- FF_LPC_TYPE_LEVINSON, 10,
- ORDER_METHOD_EST, MAX_LPC_SHIFT, 0) - 1;
-
- /* Works surprisingly well, remember to tweak MAX_LPC_SHIFT if you want to play around with this */
- if (shift[order] > 3) {
- int direction = 0;
- float tns_coefs_raw[TNS_MAX_ORDER];
- tns->n_filt[w] = filters++;
- conv_to_float(tns_coefs_raw, coefs_t[order], order);
- for (g = 0; g < tns->n_filt[w]; g++) {
- process_tns_coeffs(tns, tns_coefs_raw, order, w, g);
- apply_tns_filter(&sce->coeffs[coef_start], sce->pcoeffs, order, direction, tns->coef[w][g],
- sce->ics.ltp.present, w, g, coef_start, coef_len);
- tns->order[w][g] = order;
- tns->length[w][g] = sfb_len;
- tns->direction[w][g] = direction;
+ gain = ff_lpc_calc_ref_coefs_f(&s->lpc, &sce->coeffs[coef_start],
+ coef_len, order, coefs);
+
+ if (gain > TNS_GAIN_THRESHOLD_LOW && gain < TNS_GAIN_THRESHOLD_HIGH &&
+ (en[0]+en[1]) > TNS_GAIN_THRESHOLD_LOW*threshold &&
+ spread < TNS_SPREAD_THRESHOLD && order) {
+ if (is8 || order < 2 || (e_ratio > TNS_E_RATIO_LOW && e_ratio < TNS_E_RATIO_HIGH)) {
+ 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] = en[0] < en[1];
+ tns->order[w][g] = order;
+ quantize_coefs(coefs, tns->coef_idx[w][g], tns->coef[w][g],
+ order);
+ }
+ } 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] = 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]);
+ }
}
count++;
}