/* * AAC decoder * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org ) * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com ) * Copyright (c) 2008-2013 Alex Converse * * AAC LATM decoder * Copyright (c) 2008-2010 Paul Kendall * Copyright (c) 2010 Janne Grunau * * AAC decoder fixed-point implementation * Copyright (c) 2013 * MIPS Technologies, Inc., California. * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "aacdec.h" #include "libavcodec/lpc_functions.h" #include "libavcodec/aactab.h" /** * Convert integer scalefactors to the decoder's native expected * scalefactor values. */ static void AAC_RENAME(dequant_scalefactors)(SingleChannelElement *sce) { IndividualChannelStream *ics = &sce->ics; const enum BandType *band_type = sce->band_type; const int *band_type_run_end = sce->band_type_run_end; const int *sfo = sce->sfo; INTFLOAT *sf = sce->AAC_RENAME(sf); int g, i, idx = 0; for (g = 0; g < ics->num_window_groups; g++) { for (i = 0; i < ics->max_sfb;) { int run_end = band_type_run_end[idx]; switch (band_type[idx]) { case ZERO_BT: for (; i < run_end; i++, idx++) sf[idx] = FIXR(0.); break; case INTENSITY_BT: /* fallthrough */ case INTENSITY_BT2: for (; i < run_end; i++, idx++) { #if USE_FIXED sf[idx] = 100 - sfo[idx]; #else sf[idx] = ff_aac_pow2sf_tab[-sfo[idx] + POW_SF2_ZERO]; #endif /* USE_FIXED */ } break; case NOISE_BT: for (; i < run_end; i++, idx++) { #if USE_FIXED sf[idx] = -(100 + sfo[idx]); #else sf[idx] = -ff_aac_pow2sf_tab[sfo[idx] + POW_SF2_ZERO]; #endif /* USE_FIXED */ } break; default: for (; i < run_end; i++, idx++) { #if USE_FIXED sf[idx] = -sfo[idx]; #else sf[idx] = -ff_aac_pow2sf_tab[sfo[idx] - 100 + POW_SF2_ZERO]; #endif /* USE_FIXED */ } break; } } } } /** * Mid/Side stereo decoding; reference: 4.6.8.1.3. */ static void AAC_RENAME(apply_mid_side_stereo)(AACDecContext *ac, ChannelElement *cpe) { const IndividualChannelStream *ics = &cpe->ch[0].ics; INTFLOAT *ch0 = cpe->ch[0].AAC_RENAME(coeffs); INTFLOAT *ch1 = cpe->ch[1].AAC_RENAME(coeffs); int g, i, group, idx = 0; const uint16_t *offsets = ics->swb_offset; for (g = 0; g < ics->num_window_groups; g++) { for (i = 0; i < ics->max_sfb; i++, idx++) { if (cpe->ms_mask[idx] && cpe->ch[0].band_type[idx] < NOISE_BT && cpe->ch[1].band_type[idx] < NOISE_BT) { #if USE_FIXED for (group = 0; group < ics->group_len[g]; group++) { ac->fdsp->butterflies_fixed(ch0 + group * 128 + offsets[i], ch1 + group * 128 + offsets[i], offsets[i+1] - offsets[i]); #else for (group = 0; group < ics->group_len[g]; group++) { ac->fdsp->butterflies_float(ch0 + group * 128 + offsets[i], ch1 + group * 128 + offsets[i], offsets[i+1] - offsets[i]); #endif /* USE_FIXED */ } } } ch0 += ics->group_len[g] * 128; ch1 += ics->group_len[g] * 128; } } /** * intensity stereo decoding; reference: 4.6.8.2.3 * * @param ms_present Indicates mid/side stereo presence. [0] mask is all 0s; * [1] mask is decoded from bitstream; [2] mask is all 1s; * [3] reserved for scalable AAC */ static void AAC_RENAME(apply_intensity_stereo)(AACDecContext *ac, ChannelElement *cpe, int ms_present) { const IndividualChannelStream *ics = &cpe->ch[1].ics; SingleChannelElement *sce1 = &cpe->ch[1]; INTFLOAT *coef0 = cpe->ch[0].AAC_RENAME(coeffs), *coef1 = cpe->ch[1].AAC_RENAME(coeffs); const uint16_t *offsets = ics->swb_offset; int g, group, i, idx = 0; int c; INTFLOAT scale; for (g = 0; g < ics->num_window_groups; g++) { for (i = 0; i < ics->max_sfb;) { if (sce1->band_type[idx] == INTENSITY_BT || sce1->band_type[idx] == INTENSITY_BT2) { const int bt_run_end = sce1->band_type_run_end[idx]; for (; i < bt_run_end; i++, idx++) { c = -1 + 2 * (sce1->band_type[idx] - 14); if (ms_present) c *= 1 - 2 * cpe->ms_mask[idx]; scale = c * sce1->AAC_RENAME(sf)[idx]; for (group = 0; group < ics->group_len[g]; group++) #if USE_FIXED subband_scale(coef1 + group * 128 + offsets[i], coef0 + group * 128 + offsets[i], scale, 23, offsets[i + 1] - offsets[i] ,ac->avctx); #else ac->fdsp->vector_fmul_scalar(coef1 + group * 128 + offsets[i], coef0 + group * 128 + offsets[i], scale, offsets[i + 1] - offsets[i]); #endif /* USE_FIXED */ } } else { int bt_run_end = sce1->band_type_run_end[idx]; idx += bt_run_end - i; i = bt_run_end; } } coef0 += ics->group_len[g] * 128; coef1 += ics->group_len[g] * 128; } } /** * Decode Temporal Noise Shaping filter coefficients and apply all-pole filters; reference: 4.6.9.3. * * @param decode 1 if tool is used normally, 0 if tool is used in LTP. * @param coef spectral coefficients */ static void AAC_RENAME(apply_tns)(void *_coef_param, TemporalNoiseShaping *tns, IndividualChannelStream *ics, int decode) { const int mmm = FFMIN(ics->tns_max_bands, ics->max_sfb); int w, filt, m, i; int bottom, top, order, start, end, size, inc; INTFLOAT *coef_param = _coef_param; INTFLOAT lpc[TNS_MAX_ORDER]; INTFLOAT tmp[TNS_MAX_ORDER+1]; UINTFLOAT *coef = coef_param; if(!mmm) return; 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->AAC_RENAME(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; if (decode) { // ar filter for (m = 0; m < size; m++, start += inc) for (i = 1; i <= FFMIN(m, order); i++) coef[start] -= AAC_MUL26((INTFLOAT)coef[start - i * inc], lpc[i - 1]); } else { // ma filter for (m = 0; m < size; m++, start += inc) { tmp[0] = coef[start]; for (i = 1; i <= FFMIN(m, order); i++) coef[start] += AAC_MUL26(tmp[i], lpc[i - 1]); for (i = order; i > 0; i--) tmp[i] = tmp[i - 1]; } } } } } /** * Apply windowing and MDCT to obtain the spectral * coefficient from the predicted sample by LTP. */ static inline void AAC_RENAME(windowing_and_mdct_ltp)(AACDecContext *ac, INTFLOAT *out, INTFLOAT *in, IndividualChannelStream *ics) { const INTFLOAT *lwindow = ics->use_kb_window[0] ? AAC_RENAME2(aac_kbd_long_1024) : AAC_RENAME2(sine_1024); const INTFLOAT *swindow = ics->use_kb_window[0] ? AAC_RENAME2(aac_kbd_short_128) : AAC_RENAME2(sine_128); const INTFLOAT *lwindow_prev = ics->use_kb_window[1] ? AAC_RENAME2(aac_kbd_long_1024) : AAC_RENAME2(sine_1024); const INTFLOAT *swindow_prev = ics->use_kb_window[1] ? AAC_RENAME2(aac_kbd_short_128) : AAC_RENAME2(sine_128); if (ics->window_sequence[0] != LONG_STOP_SEQUENCE) { ac->fdsp->vector_fmul(in, in, lwindow_prev, 1024); } else { memset(in, 0, 448 * sizeof(*in)); ac->fdsp->vector_fmul(in + 448, in + 448, swindow_prev, 128); } if (ics->window_sequence[0] != LONG_START_SEQUENCE) { ac->fdsp->vector_fmul_reverse(in + 1024, in + 1024, lwindow, 1024); } else { ac->fdsp->vector_fmul_reverse(in + 1024 + 448, in + 1024 + 448, swindow, 128); memset(in + 1024 + 576, 0, 448 * sizeof(*in)); } ac->mdct_ltp_fn(ac->mdct_ltp, out, in, sizeof(INTFLOAT)); } /** * Apply the long term prediction */ static void AAC_RENAME(apply_ltp)(AACDecContext *ac, SingleChannelElement *sce) { const LongTermPrediction *ltp = &sce->ics.ltp; const uint16_t *offsets = sce->ics.swb_offset; int i, sfb; if (sce->ics.window_sequence[0] != EIGHT_SHORT_SEQUENCE) { INTFLOAT *predTime = sce->AAC_RENAME(output); INTFLOAT *predFreq = ac->AAC_RENAME(buf_mdct); int16_t num_samples = 2048; if (ltp->lag < 1024) num_samples = ltp->lag + 1024; for (i = 0; i < num_samples; i++) predTime[i] = AAC_MUL30(sce->AAC_RENAME(ltp_state)[i + 2048 - ltp->lag], ltp->AAC_RENAME(coef)); memset(&predTime[i], 0, (2048 - i) * sizeof(*predTime)); AAC_RENAME(windowing_and_mdct_ltp)(ac, predFreq, predTime, &sce->ics); if (sce->tns.present) AAC_RENAME(apply_tns)(predFreq, &sce->tns, &sce->ics, 0); for (sfb = 0; sfb < FFMIN(sce->ics.max_sfb, MAX_LTP_LONG_SFB); sfb++) if (ltp->used[sfb]) for (i = offsets[sfb]; i < offsets[sfb + 1]; i++) sce->AAC_RENAME(coeffs)[i] += (UINTFLOAT)predFreq[i]; } } /** * Update the LTP buffer for next frame */ static void AAC_RENAME(update_ltp)(AACDecContext *ac, SingleChannelElement *sce) { IndividualChannelStream *ics = &sce->ics; INTFLOAT *saved = sce->AAC_RENAME(saved); INTFLOAT *saved_ltp = sce->AAC_RENAME(coeffs); const INTFLOAT *lwindow = ics->use_kb_window[0] ? AAC_RENAME2(aac_kbd_long_1024) : AAC_RENAME2(sine_1024); const INTFLOAT *swindow = ics->use_kb_window[0] ? AAC_RENAME2(aac_kbd_short_128) : AAC_RENAME2(sine_128); int i; if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { memcpy(saved_ltp, saved, 512 * sizeof(*saved_ltp)); memset(saved_ltp + 576, 0, 448 * sizeof(*saved_ltp)); ac->fdsp->vector_fmul_reverse(saved_ltp + 448, ac->AAC_RENAME(buf_mdct) + 960, &swindow[64], 64); for (i = 0; i < 64; i++) saved_ltp[i + 512] = AAC_MUL31(ac->AAC_RENAME(buf_mdct)[1023 - i], swindow[63 - i]); } else if (1 && ics->window_sequence[0] == LONG_START_SEQUENCE) { memcpy(saved_ltp, ac->AAC_RENAME(buf_mdct) + 512, 448 * sizeof(*saved_ltp)); memset(saved_ltp + 576, 0, 448 * sizeof(*saved_ltp)); ac->fdsp->vector_fmul_reverse(saved_ltp + 448, ac->AAC_RENAME(buf_mdct) + 960, &swindow[64], 64); for (i = 0; i < 64; i++) saved_ltp[i + 512] = AAC_MUL31(ac->AAC_RENAME(buf_mdct)[1023 - i], swindow[63 - i]); } else if (1) { // LONG_STOP or ONLY_LONG ac->fdsp->vector_fmul_reverse(saved_ltp, ac->AAC_RENAME(buf_mdct) + 512, &lwindow[512], 512); for (i = 0; i < 512; i++) saved_ltp[i + 512] = AAC_MUL31(ac->AAC_RENAME(buf_mdct)[1023 - i], lwindow[511 - i]); } memcpy(sce->AAC_RENAME(ltp_state), sce->AAC_RENAME(ltp_state)+1024, 1024 * sizeof(*sce->AAC_RENAME(ltp_state))); memcpy(sce->AAC_RENAME(ltp_state) + 1024, sce->AAC_RENAME(output), 1024 * sizeof(*sce->AAC_RENAME(ltp_state))); memcpy(sce->AAC_RENAME(ltp_state) + 2048, saved_ltp, 1024 * sizeof(*sce->AAC_RENAME(ltp_state))); } /** * Conduct IMDCT and windowing. */ static void AAC_RENAME(imdct_and_windowing)(AACDecContext *ac, SingleChannelElement *sce) { IndividualChannelStream *ics = &sce->ics; INTFLOAT *in = sce->AAC_RENAME(coeffs); INTFLOAT *out = sce->AAC_RENAME(output); INTFLOAT *saved = sce->AAC_RENAME(saved); const INTFLOAT *swindow = ics->use_kb_window[0] ? AAC_RENAME2(aac_kbd_short_128) : AAC_RENAME2(sine_128); const INTFLOAT *lwindow_prev = ics->use_kb_window[1] ? AAC_RENAME2(aac_kbd_long_1024) : AAC_RENAME2(sine_1024); const INTFLOAT *swindow_prev = ics->use_kb_window[1] ? AAC_RENAME2(aac_kbd_short_128) : AAC_RENAME2(sine_128); INTFLOAT *buf = ac->AAC_RENAME(buf_mdct); INTFLOAT *temp = ac->AAC_RENAME(temp); int i; // imdct if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { for (i = 0; i < 1024; i += 128) ac->mdct128_fn(ac->mdct128, buf + i, in + i, sizeof(INTFLOAT)); } else { ac->mdct1024_fn(ac->mdct1024, buf, in, sizeof(INTFLOAT)); } /* window overlapping * NOTE: To simplify the overlapping code, all 'meaningless' short to long * and long to short transitions are considered to be short to short * transitions. This leaves just two cases (long to long and short to short) * with a little special sauce for EIGHT_SHORT_SEQUENCE. */ if ((ics->window_sequence[1] == ONLY_LONG_SEQUENCE || ics->window_sequence[1] == LONG_STOP_SEQUENCE) && (ics->window_sequence[0] == ONLY_LONG_SEQUENCE || ics->window_sequence[0] == LONG_START_SEQUENCE)) { ac->fdsp->vector_fmul_window( out, saved, buf, lwindow_prev, 512); } else { memcpy( out, saved, 448 * sizeof(*out)); if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { ac->fdsp->vector_fmul_window(out + 448 + 0*128, saved + 448, buf + 0*128, swindow_prev, 64); ac->fdsp->vector_fmul_window(out + 448 + 1*128, buf + 0*128 + 64, buf + 1*128, swindow, 64); ac->fdsp->vector_fmul_window(out + 448 + 2*128, buf + 1*128 + 64, buf + 2*128, swindow, 64); ac->fdsp->vector_fmul_window(out + 448 + 3*128, buf + 2*128 + 64, buf + 3*128, swindow, 64); ac->fdsp->vector_fmul_window(temp, buf + 3*128 + 64, buf + 4*128, swindow, 64); memcpy( out + 448 + 4*128, temp, 64 * sizeof(*out)); } else { ac->fdsp->vector_fmul_window(out + 448, saved + 448, buf, swindow_prev, 64); memcpy( out + 576, buf + 64, 448 * sizeof(*out)); } } // buffer update if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { memcpy( saved, temp + 64, 64 * sizeof(*saved)); ac->fdsp->vector_fmul_window(saved + 64, buf + 4*128 + 64, buf + 5*128, swindow, 64); ac->fdsp->vector_fmul_window(saved + 192, buf + 5*128 + 64, buf + 6*128, swindow, 64); ac->fdsp->vector_fmul_window(saved + 320, buf + 6*128 + 64, buf + 7*128, swindow, 64); memcpy( saved + 448, buf + 7*128 + 64, 64 * sizeof(*saved)); } else if (ics->window_sequence[0] == LONG_START_SEQUENCE) { memcpy( saved, buf + 512, 448 * sizeof(*saved)); memcpy( saved + 448, buf + 7*128 + 64, 64 * sizeof(*saved)); } else { // LONG_STOP or ONLY_LONG memcpy( saved, buf + 512, 512 * sizeof(*saved)); } } /** * Conduct IMDCT and windowing. */ static void AAC_RENAME(imdct_and_windowing_960)(AACDecContext *ac, SingleChannelElement *sce) { IndividualChannelStream *ics = &sce->ics; INTFLOAT *in = sce->AAC_RENAME(coeffs); INTFLOAT *out = sce->AAC_RENAME(output); INTFLOAT *saved = sce->AAC_RENAME(saved); const INTFLOAT *swindow = ics->use_kb_window[0] ? AAC_RENAME(aac_kbd_short_120) : AAC_RENAME(sine_120); const INTFLOAT *lwindow_prev = ics->use_kb_window[1] ? AAC_RENAME(aac_kbd_long_960) : AAC_RENAME(sine_960); const INTFLOAT *swindow_prev = ics->use_kb_window[1] ? AAC_RENAME(aac_kbd_short_120) : AAC_RENAME(sine_120); INTFLOAT *buf = ac->AAC_RENAME(buf_mdct); INTFLOAT *temp = ac->AAC_RENAME(temp); int i; // imdct if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { for (i = 0; i < 8; i++) ac->mdct120_fn(ac->mdct120, buf + i * 120, in + i * 128, sizeof(INTFLOAT)); } else { ac->mdct960_fn(ac->mdct960, buf, in, sizeof(INTFLOAT)); } /* window overlapping * NOTE: To simplify the overlapping code, all 'meaningless' short to long * and long to short transitions are considered to be short to short * transitions. This leaves just two cases (long to long and short to short) * with a little special sauce for EIGHT_SHORT_SEQUENCE. */ if ((ics->window_sequence[1] == ONLY_LONG_SEQUENCE || ics->window_sequence[1] == LONG_STOP_SEQUENCE) && (ics->window_sequence[0] == ONLY_LONG_SEQUENCE || ics->window_sequence[0] == LONG_START_SEQUENCE)) { ac->fdsp->vector_fmul_window( out, saved, buf, lwindow_prev, 480); } else { memcpy( out, saved, 420 * sizeof(*out)); if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { ac->fdsp->vector_fmul_window(out + 420 + 0*120, saved + 420, buf + 0*120, swindow_prev, 60); ac->fdsp->vector_fmul_window(out + 420 + 1*120, buf + 0*120 + 60, buf + 1*120, swindow, 60); ac->fdsp->vector_fmul_window(out + 420 + 2*120, buf + 1*120 + 60, buf + 2*120, swindow, 60); ac->fdsp->vector_fmul_window(out + 420 + 3*120, buf + 2*120 + 60, buf + 3*120, swindow, 60); ac->fdsp->vector_fmul_window(temp, buf + 3*120 + 60, buf + 4*120, swindow, 60); memcpy( out + 420 + 4*120, temp, 60 * sizeof(*out)); } else { ac->fdsp->vector_fmul_window(out + 420, saved + 420, buf, swindow_prev, 60); memcpy( out + 540, buf + 60, 420 * sizeof(*out)); } } // buffer update if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) { memcpy( saved, temp + 60, 60 * sizeof(*saved)); ac->fdsp->vector_fmul_window(saved + 60, buf + 4*120 + 60, buf + 5*120, swindow, 60); ac->fdsp->vector_fmul_window(saved + 180, buf + 5*120 + 60, buf + 6*120, swindow, 60); ac->fdsp->vector_fmul_window(saved + 300, buf + 6*120 + 60, buf + 7*120, swindow, 60); memcpy( saved + 420, buf + 7*120 + 60, 60 * sizeof(*saved)); } else if (ics->window_sequence[0] == LONG_START_SEQUENCE) { memcpy( saved, buf + 480, 420 * sizeof(*saved)); memcpy( saved + 420, buf + 7*120 + 60, 60 * sizeof(*saved)); } else { // LONG_STOP or ONLY_LONG memcpy( saved, buf + 480, 480 * sizeof(*saved)); } } static void AAC_RENAME(imdct_and_windowing_ld)(AACDecContext *ac, SingleChannelElement *sce) { IndividualChannelStream *ics = &sce->ics; INTFLOAT *in = sce->AAC_RENAME(coeffs); INTFLOAT *out = sce->AAC_RENAME(output); INTFLOAT *saved = sce->AAC_RENAME(saved); INTFLOAT *buf = ac->AAC_RENAME(buf_mdct); // imdct ac->mdct512_fn(ac->mdct512, buf, in, sizeof(INTFLOAT)); // window overlapping if (ics->use_kb_window[1]) { // AAC LD uses a low overlap sine window instead of a KBD window memcpy(out, saved, 192 * sizeof(*out)); ac->fdsp->vector_fmul_window(out + 192, saved + 192, buf, AAC_RENAME2(sine_128), 64); memcpy( out + 320, buf + 64, 192 * sizeof(*out)); } else { ac->fdsp->vector_fmul_window(out, saved, buf, AAC_RENAME2(sine_512), 256); } // buffer update memcpy(saved, buf + 256, 256 * sizeof(*saved)); } static void AAC_RENAME(imdct_and_windowing_eld)(AACDecContext *ac, SingleChannelElement *sce) { UINTFLOAT *in = sce->AAC_RENAME(coeffs); INTFLOAT *out = sce->AAC_RENAME(output); INTFLOAT *saved = sce->AAC_RENAME(saved); INTFLOAT *buf = ac->AAC_RENAME(buf_mdct); int i; const int n = ac->oc[1].m4ac.frame_length_short ? 480 : 512; const int n2 = n >> 1; const int n4 = n >> 2; const INTFLOAT *const window = n == 480 ? AAC_RENAME(ff_aac_eld_window_480) : AAC_RENAME(ff_aac_eld_window_512); // Inverse transform, mapped to the conventional IMDCT by // Chivukula, R.K.; Reznik, Y.A.; Devarajan, V., // "Efficient algorithms for MPEG-4 AAC-ELD, AAC-LD and AAC-LC filterbanks," // International Conference on Audio, Language and Image Processing, ICALIP 2008. // URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4590245&isnumber=4589950 for (i = 0; i < n2; i+=2) { INTFLOAT temp; temp = in[i ]; in[i ] = -in[n - 1 - i]; in[n - 1 - i] = temp; temp = -in[i + 1]; in[i + 1] = in[n - 2 - i]; in[n - 2 - i] = temp; } if (n == 480) ac->mdct480_fn(ac->mdct480, buf, in, sizeof(INTFLOAT)); else ac->mdct512_fn(ac->mdct512, buf, in, sizeof(INTFLOAT)); for (i = 0; i < n; i+=2) { buf[i + 0] = -(UINTFLOAT)(USE_FIXED + 1)*buf[i + 0]; buf[i + 1] = (UINTFLOAT)(USE_FIXED + 1)*buf[i + 1]; } // Like with the regular IMDCT at this point we still have the middle half // of a transform but with even symmetry on the left and odd symmetry on // the right // window overlapping // The spec says to use samples [0..511] but the reference decoder uses // samples [128..639]. for (i = n4; i < n2; i ++) { out[i - n4] = AAC_MUL31( buf[ n2 - 1 - i] , window[i - n4]) + AAC_MUL31( saved[ i + n2] , window[i + n - n4]) + AAC_MUL31(-saved[n + n2 - 1 - i] , window[i + 2*n - n4]) + AAC_MUL31(-saved[ 2*n + n2 + i] , window[i + 3*n - n4]); } for (i = 0; i < n2; i ++) { out[n4 + i] = AAC_MUL31( buf[ i] , window[i + n2 - n4]) + AAC_MUL31(-saved[ n - 1 - i] , window[i + n2 + n - n4]) + AAC_MUL31(-saved[ n + i] , window[i + n2 + 2*n - n4]) + AAC_MUL31( saved[2*n + n - 1 - i] , window[i + n2 + 3*n - n4]); } for (i = 0; i < n4; i ++) { out[n2 + n4 + i] = AAC_MUL31( buf[ i + n2] , window[i + n - n4]) + AAC_MUL31(-saved[n2 - 1 - i] , window[i + 2*n - n4]) + AAC_MUL31(-saved[n + n2 + i] , window[i + 3*n - n4]); } // buffer update memmove(saved + n, saved, 2 * n * sizeof(*saved)); memcpy( saved, buf, n * sizeof(*saved)); } static void AAC_RENAME(clip_output)(AACDecContext *ac, ChannelElement *che, int type, int samples) { #if USE_FIXED /* preparation for resampler */ for (int j = 0; j < samples; j++){ che->ch[0].output_fixed[j] = (int32_t)av_clip64((int64_t)che->ch[0].output_fixed[j]*128, INT32_MIN, INT32_MAX-0x8000)+0x8000; if (type == TYPE_CPE || (type == TYPE_SCE && ac->oc[1].m4ac.ps == 1)) che->ch[1].output_fixed[j] = (int32_t)av_clip64((int64_t)che->ch[1].output_fixed[j]*128, INT32_MIN, INT32_MAX-0x8000)+0x8000; } #endif } static inline void reset_all_predictors(PredictorState *ps) { int i; for (i = 0; i < MAX_PREDICTORS; i++) reset_predict_state(&ps[i]); } static inline void reset_predictor_group(PredictorState *ps, int group_num) { int i; for (i = group_num - 1; i < MAX_PREDICTORS; i += 30) reset_predict_state(&ps[i]); } /** * Apply AAC-Main style frequency domain prediction. */ static void AAC_RENAME(apply_prediction)(AACDecContext *ac, SingleChannelElement *sce) { int sfb, k; if (!sce->ics.predictor_initialized) { reset_all_predictors(sce->AAC_RENAME(predictor_state)); sce->ics.predictor_initialized = 1; } if (sce->ics.window_sequence[0] != EIGHT_SHORT_SEQUENCE) { for (sfb = 0; sfb < ff_aac_pred_sfb_max[ac->oc[1].m4ac.sampling_index]; sfb++) { for (k = sce->ics.swb_offset[sfb]; k < sce->ics.swb_offset[sfb + 1]; k++) { predict(&sce->AAC_RENAME(predictor_state)[k], &sce->AAC_RENAME(coeffs)[k], sce->ics.predictor_present && sce->ics.prediction_used[sfb]); } } if (sce->ics.predictor_reset_group) reset_predictor_group(sce->AAC_RENAME(predictor_state), sce->ics.predictor_reset_group); } else reset_all_predictors(sce->AAC_RENAME(predictor_state)); } static av_cold void AAC_RENAME(aac_dsp_init)(AACDecDSP *aac_dsp) { #define SET(member) aac_dsp->member = AAC_RENAME(member) SET(dequant_scalefactors); SET(apply_mid_side_stereo); SET(apply_intensity_stereo); SET(apply_tns); SET(apply_ltp); SET(update_ltp); SET(apply_prediction); SET(imdct_and_windowing); SET(imdct_and_windowing_960); SET(imdct_and_windowing_ld); SET(imdct_and_windowing_eld); SET(apply_dependent_coupling); SET(apply_independent_coupling); SET(clip_output); #undef SET }