diff options
Diffstat (limited to 'libavcodec/aacenc_tns.c')
-rw-r--r-- | libavcodec/aacenc_tns.c | 66 |
1 files changed, 26 insertions, 40 deletions
diff --git a/libavcodec/aacenc_tns.c b/libavcodec/aacenc_tns.c index 85fcb0f33b..84f5d09693 100644 --- a/libavcodec/aacenc_tns.c +++ b/libavcodec/aacenc_tns.c @@ -35,17 +35,14 @@ #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) { @@ -71,8 +68,8 @@ 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; @@ -152,7 +149,7 @@ static inline void quantize_coefs(double *coef, int *idx, float *lpc, int order, 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]]; } } @@ -163,36 +160,37 @@ static inline void quantize_coefs(double *coef, int *idx, float *lpc, int order, 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 */ @@ -201,30 +199,18 @@ void ff_aac_search_for_tns(AACEncContext *s, SingleChannelElement *sce) 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; } |