/* * Copyright (c) 2012 Andrew D'Addesio * Copyright (c) 2013-2014 Mozilla Corporation * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Opus CELT decoder */ #include #include "libavutil/float_dsp.h" #include "imdct15.h" #include "opus.h" enum CeltSpread { CELT_SPREAD_NONE, CELT_SPREAD_LIGHT, CELT_SPREAD_NORMAL, CELT_SPREAD_AGGRESSIVE }; typedef struct CeltFrame { float energy[CELT_MAX_BANDS]; float prev_energy[2][CELT_MAX_BANDS]; uint8_t collapse_masks[CELT_MAX_BANDS]; /* buffer for mdct output + postfilter */ DECLARE_ALIGNED(32, float, buf)[2048]; /* postfilter parameters */ int pf_period_new; float pf_gains_new[3]; int pf_period; float pf_gains[3]; int pf_period_old; float pf_gains_old[3]; float deemph_coeff; } CeltFrame; struct CeltContext { // constant values that do not change during context lifetime AVCodecContext *avctx; IMDCT15Context *imdct[4]; AVFloatDSPContext dsp; int output_channels; // values that have inter-frame effect and must be reset on flush CeltFrame frame[2]; uint32_t seed; int flushed; // values that only affect a single frame int coded_channels; int framebits; int duration; /* number of iMDCT blocks in the frame */ int blocks; /* size of each block */ int blocksize; int startband; int endband; int codedbands; int anticollapse_bit; int intensitystereo; int dualstereo; enum CeltSpread spread; int remaining; int remaining2; int fine_bits [CELT_MAX_BANDS]; int fine_priority[CELT_MAX_BANDS]; int pulses [CELT_MAX_BANDS]; int tf_change [CELT_MAX_BANDS]; DECLARE_ALIGNED(32, float, coeffs)[2][CELT_MAX_FRAME_SIZE]; DECLARE_ALIGNED(32, float, scratch)[22 * 8]; // MAX(celt_freq_range) * 1<> 13; x = (32767-x) + ROUND_MUL16(x, (-7651 + ROUND_MUL16(x, (8277 + ROUND_MUL16(-626, x))))); return 1+x; } static inline int celt_log2tan(int isin, int icos) { int lc, ls; lc = opus_ilog(icos); ls = opus_ilog(isin); icos <<= 15 - lc; isin <<= 15 - ls; return (ls << 11) - (lc << 11) + ROUND_MUL16(isin, ROUND_MUL16(isin, -2597) + 7932) - ROUND_MUL16(icos, ROUND_MUL16(icos, -2597) + 7932); } static inline uint32_t celt_rng(CeltContext *s) { s->seed = 1664525 * s->seed + 1013904223; return s->seed; } static void celt_decode_coarse_energy(CeltContext *s, OpusRangeCoder *rc) { int i, j; float prev[2] = {0}; float alpha, beta; const uint8_t *model; /* use the 2D z-transform to apply prediction in both */ /* the time domain (alpha) and the frequency domain (beta) */ if (opus_rc_tell(rc)+3 <= s->framebits && opus_rc_p2model(rc, 3)) { /* intra frame */ alpha = 0; beta = 1.0f - 4915.0f/32768.0f; model = celt_coarse_energy_dist[s->duration][1]; } else { alpha = celt_alpha_coef[s->duration]; beta = 1.0f - celt_beta_coef[s->duration]; model = celt_coarse_energy_dist[s->duration][0]; } for (i = 0; i < CELT_MAX_BANDS; i++) { for (j = 0; j < s->coded_channels; j++) { CeltFrame *frame = &s->frame[j]; float value; int available; if (i < s->startband || i >= s->endband) { frame->energy[i] = 0.0; continue; } available = s->framebits - opus_rc_tell(rc); if (available >= 15) { /* decode using a Laplace distribution */ int k = FFMIN(i, 20) << 1; value = opus_rc_laplace(rc, model[k] << 7, model[k+1] << 6); } else if (available >= 2) { int x = opus_rc_getsymbol(rc, celt_model_energy_small); value = (x>>1) ^ -(x&1); } else if (available >= 1) { value = -(float)opus_rc_p2model(rc, 1); } else value = -1; frame->energy[i] = FFMAX(-9.0f, frame->energy[i]) * alpha + prev[j] + value; prev[j] += beta * value; } } } static void celt_decode_fine_energy(CeltContext *s, OpusRangeCoder *rc) { int i; for (i = s->startband; i < s->endband; i++) { int j; if (!s->fine_bits[i]) continue; for (j = 0; j < s->coded_channels; j++) { CeltFrame *frame = &s->frame[j]; int q2; float offset; q2 = opus_getrawbits(rc, s->fine_bits[i]); offset = (q2 + 0.5f) * (1 << (14 - s->fine_bits[i])) / 16384.0f - 0.5f; frame->energy[i] += offset; } } } static void celt_decode_final_energy(CeltContext *s, OpusRangeCoder *rc, int bits_left) { int priority, i, j; for (priority = 0; priority < 2; priority++) { for (i = s->startband; i < s->endband && bits_left >= s->coded_channels; i++) { if (s->fine_priority[i] != priority || s->fine_bits[i] >= CELT_MAX_FINE_BITS) continue; for (j = 0; j < s->coded_channels; j++) { int q2; float offset; q2 = opus_getrawbits(rc, 1); offset = (q2 - 0.5f) * (1 << (14 - s->fine_bits[i] - 1)) / 16384.0f; s->frame[j].energy[i] += offset; bits_left--; } } } } static void celt_decode_tf_changes(CeltContext *s, OpusRangeCoder *rc, int transient) { int i, diff = 0, tf_select = 0, tf_changed = 0, tf_select_bit; int consumed, bits = transient ? 2 : 4; consumed = opus_rc_tell(rc); tf_select_bit = (s->duration != 0 && consumed+bits+1 <= s->framebits); for (i = s->startband; i < s->endband; i++) { if (consumed+bits+tf_select_bit <= s->framebits) { diff ^= opus_rc_p2model(rc, bits); consumed = opus_rc_tell(rc); tf_changed |= diff; } s->tf_change[i] = diff; bits = transient ? 4 : 5; } if (tf_select_bit && celt_tf_select[s->duration][transient][0][tf_changed] != celt_tf_select[s->duration][transient][1][tf_changed]) tf_select = opus_rc_p2model(rc, 1); for (i = s->startband; i < s->endband; i++) { s->tf_change[i] = celt_tf_select[s->duration][transient][tf_select][s->tf_change[i]]; } } static void celt_decode_allocation(CeltContext *s, OpusRangeCoder *rc) { // approx. maximum bit allocation for each band before boost/trim int cap[CELT_MAX_BANDS]; int boost[CELT_MAX_BANDS]; int threshold[CELT_MAX_BANDS]; int bits1[CELT_MAX_BANDS]; int bits2[CELT_MAX_BANDS]; int trim_offset[CELT_MAX_BANDS]; int skip_startband = s->startband; int dynalloc = 6; int alloctrim = 5; int extrabits = 0; int skip_bit = 0; int intensitystereo_bit = 0; int dualstereo_bit = 0; int remaining, bandbits; int low, high, total, done; int totalbits; int consumed; int i, j; consumed = opus_rc_tell(rc); /* obtain spread flag */ s->spread = CELT_SPREAD_NORMAL; if (consumed + 4 <= s->framebits) s->spread = opus_rc_getsymbol(rc, celt_model_spread); /* generate static allocation caps */ for (i = 0; i < CELT_MAX_BANDS; i++) { cap[i] = (celt_static_caps[s->duration][s->coded_channels - 1][i] + 64) * celt_freq_range[i] << (s->coded_channels - 1) << s->duration >> 2; } /* obtain band boost */ totalbits = s->framebits << 3; // convert to 1/8 bits consumed = opus_rc_tell_frac(rc); for (i = s->startband; i < s->endband; i++) { int quanta, band_dynalloc; boost[i] = 0; quanta = celt_freq_range[i] << (s->coded_channels - 1) << s->duration; quanta = FFMIN(quanta << 3, FFMAX(6 << 3, quanta)); band_dynalloc = dynalloc; while (consumed + (band_dynalloc<<3) < totalbits && boost[i] < cap[i]) { int add = opus_rc_p2model(rc, band_dynalloc); consumed = opus_rc_tell_frac(rc); if (!add) break; boost[i] += quanta; totalbits -= quanta; band_dynalloc = 1; } /* dynalloc is more likely to occur if it's already been used for earlier bands */ if (boost[i]) dynalloc = FFMAX(2, dynalloc - 1); } /* obtain allocation trim */ if (consumed + (6 << 3) <= totalbits) alloctrim = opus_rc_getsymbol(rc, celt_model_alloc_trim); /* anti-collapse bit reservation */ totalbits = (s->framebits << 3) - opus_rc_tell_frac(rc) - 1; s->anticollapse_bit = 0; if (s->blocks > 1 && s->duration >= 2 && totalbits >= ((s->duration + 2) << 3)) s->anticollapse_bit = 1 << 3; totalbits -= s->anticollapse_bit; /* band skip bit reservation */ if (totalbits >= 1 << 3) skip_bit = 1 << 3; totalbits -= skip_bit; /* intensity/dual stereo bit reservation */ if (s->coded_channels == 2) { intensitystereo_bit = celt_log2_frac[s->endband - s->startband]; if (intensitystereo_bit <= totalbits) { totalbits -= intensitystereo_bit; if (totalbits >= 1 << 3) { dualstereo_bit = 1 << 3; totalbits -= 1 << 3; } } else intensitystereo_bit = 0; } for (i = s->startband; i < s->endband; i++) { int trim = alloctrim - 5 - s->duration; int band = celt_freq_range[i] * (s->endband - i - 1); int duration = s->duration + 3; int scale = duration + s->coded_channels - 1; /* PVQ minimum allocation threshold, below this value the band is * skipped */ threshold[i] = FFMAX(3 * celt_freq_range[i] << duration >> 4, s->coded_channels << 3); trim_offset[i] = trim * (band << scale) >> 6; if (celt_freq_range[i] << s->duration == 1) trim_offset[i] -= s->coded_channels << 3; } /* bisection */ low = 1; high = CELT_VECTORS - 1; while (low <= high) { int center = (low + high) >> 1; done = total = 0; for (i = s->endband - 1; i >= s->startband; i--) { bandbits = celt_freq_range[i] * celt_static_alloc[center][i] << (s->coded_channels - 1) << s->duration >> 2; if (bandbits) bandbits = FFMAX(0, bandbits + trim_offset[i]); bandbits += boost[i]; if (bandbits >= threshold[i] || done) { done = 1; total += FFMIN(bandbits, cap[i]); } else if (bandbits >= s->coded_channels << 3) total += s->coded_channels << 3; } if (total > totalbits) high = center - 1; else low = center + 1; } high = low--; for (i = s->startband; i < s->endband; i++) { bits1[i] = celt_freq_range[i] * celt_static_alloc[low][i] << (s->coded_channels - 1) << s->duration >> 2; bits2[i] = high >= CELT_VECTORS ? cap[i] : celt_freq_range[i] * celt_static_alloc[high][i] << (s->coded_channels - 1) << s->duration >> 2; if (bits1[i]) bits1[i] = FFMAX(0, bits1[i] + trim_offset[i]); if (bits2[i]) bits2[i] = FFMAX(0, bits2[i] + trim_offset[i]); if (low) bits1[i] += boost[i]; bits2[i] += boost[i]; if (boost[i]) skip_startband = i; bits2[i] = FFMAX(0, bits2[i] - bits1[i]); } /* bisection */ low = 0; high = 1 << CELT_ALLOC_STEPS; for (i = 0; i < CELT_ALLOC_STEPS; i++) { int center = (low + high) >> 1; done = total = 0; for (j = s->endband - 1; j >= s->startband; j--) { bandbits = bits1[j] + (center * bits2[j] >> CELT_ALLOC_STEPS); if (bandbits >= threshold[j] || done) { done = 1; total += FFMIN(bandbits, cap[j]); } else if (bandbits >= s->coded_channels << 3) total += s->coded_channels << 3; } if (total > totalbits) high = center; else low = center; } done = total = 0; for (i = s->endband - 1; i >= s->startband; i--) { bandbits = bits1[i] + (low * bits2[i] >> CELT_ALLOC_STEPS); if (bandbits >= threshold[i] || done) done = 1; else bandbits = (bandbits >= s->coded_channels << 3) ? s->coded_channels << 3 : 0; bandbits = FFMIN(bandbits, cap[i]); s->pulses[i] = bandbits; total += bandbits; } /* band skipping */ for (s->codedbands = s->endband; ; s->codedbands--) { int allocation; j = s->codedbands - 1; if (j == skip_startband) { /* all remaining bands are not skipped */ totalbits += skip_bit; break; } /* determine the number of bits available for coding "do not skip" markers */ remaining = totalbits - total; bandbits = remaining / (celt_freq_bands[j+1] - celt_freq_bands[s->startband]); remaining -= bandbits * (celt_freq_bands[j+1] - celt_freq_bands[s->startband]); allocation = s->pulses[j] + bandbits * celt_freq_range[j] + FFMAX(0, remaining - (celt_freq_bands[j] - celt_freq_bands[s->startband])); /* a "do not skip" marker is only coded if the allocation is above the chosen threshold */ if (allocation >= FFMAX(threshold[j], (s->coded_channels + 1) <<3 )) { if (opus_rc_p2model(rc, 1)) break; total += 1 << 3; allocation -= 1 << 3; } /* the band is skipped, so reclaim its bits */ total -= s->pulses[j]; if (intensitystereo_bit) { total -= intensitystereo_bit; intensitystereo_bit = celt_log2_frac[j - s->startband]; total += intensitystereo_bit; } total += s->pulses[j] = (allocation >= s->coded_channels << 3) ? s->coded_channels << 3 : 0; } /* obtain stereo flags */ s->intensitystereo = 0; s->dualstereo = 0; if (intensitystereo_bit) s->intensitystereo = s->startband + opus_rc_unimodel(rc, s->codedbands + 1 - s->startband); if (s->intensitystereo <= s->startband) totalbits += dualstereo_bit; /* no intensity stereo means no dual stereo */ else if (dualstereo_bit) s->dualstereo = opus_rc_p2model(rc, 1); /* supply the remaining bits in this frame to lower bands */ remaining = totalbits - total; bandbits = remaining / (celt_freq_bands[s->codedbands] - celt_freq_bands[s->startband]); remaining -= bandbits * (celt_freq_bands[s->codedbands] - celt_freq_bands[s->startband]); for (i = s->startband; i < s->codedbands; i++) { int bits = FFMIN(remaining, celt_freq_range[i]); s->pulses[i] += bits + bandbits * celt_freq_range[i]; remaining -= bits; } for (i = s->startband; i < s->codedbands; i++) { int N = celt_freq_range[i] << s->duration; int prev_extra = extrabits; s->pulses[i] += extrabits; if (N > 1) { int dof; // degrees of freedom int temp; // dof * channels * log(dof) int offset; // fine energy quantization offset, i.e. // extra bits assigned over the standard // totalbits/dof int fine_bits, max_bits; extrabits = FFMAX(0, s->pulses[i] - cap[i]); s->pulses[i] -= extrabits; /* intensity stereo makes use of an extra degree of freedom */ dof = N * s->coded_channels + (s->coded_channels == 2 && N > 2 && !s->dualstereo && i < s->intensitystereo); temp = dof * (celt_log_freq_range[i] + (s->duration<<3)); offset = (temp >> 1) - dof * CELT_FINE_OFFSET; if (N == 2) /* dof=2 is the only case that doesn't fit the model */ offset += dof<<1; /* grant an additional bias for the first and second pulses */ if (s->pulses[i] + offset < 2 * (dof << 3)) offset += temp >> 2; else if (s->pulses[i] + offset < 3 * (dof << 3)) offset += temp >> 3; fine_bits = (s->pulses[i] + offset + (dof << 2)) / (dof << 3); max_bits = FFMIN((s->pulses[i]>>3) >> (s->coded_channels - 1), CELT_MAX_FINE_BITS); max_bits = FFMAX(max_bits, 0); s->fine_bits[i] = av_clip(fine_bits, 0, max_bits); /* if fine_bits was rounded down or capped, give priority for the final fine energy pass */ s->fine_priority[i] = (s->fine_bits[i] * (dof<<3) >= s->pulses[i] + offset); /* the remaining bits are assigned to PVQ */ s->pulses[i] -= s->fine_bits[i] << (s->coded_channels - 1) << 3; } else { /* all bits go to fine energy except for the sign bit */ extrabits = FFMAX(0, s->pulses[i] - (s->coded_channels << 3)); s->pulses[i] -= extrabits; s->fine_bits[i] = 0; s->fine_priority[i] = 1; } /* hand back a limited number of extra fine energy bits to this band */ if (extrabits > 0) { int fineextra = FFMIN(extrabits >> (s->coded_channels + 2), CELT_MAX_FINE_BITS - s->fine_bits[i]); s->fine_bits[i] += fineextra; fineextra <<= s->coded_channels + 2; s->fine_priority[i] = (fineextra >= extrabits - prev_extra); extrabits -= fineextra; } } s->remaining = extrabits; /* skipped bands dedicate all of their bits for fine energy */ for (; i < s->endband; i++) { s->fine_bits[i] = s->pulses[i] >> (s->coded_channels - 1) >> 3; s->pulses[i] = 0; s->fine_priority[i] = s->fine_bits[i] < 1; } } static inline int celt_bits2pulses(const uint8_t *cache, int bits) { // TODO: Find the size of cache and make it into an array in the parameters list int i, low = 0, high; high = cache[0]; bits--; for (i = 0; i < 6; i++) { int center = (low + high + 1) >> 1; if (cache[center] >= bits) high = center; else low = center; } return (bits - (low == 0 ? -1 : cache[low]) <= cache[high] - bits) ? low : high; } static inline int celt_pulses2bits(const uint8_t *cache, int pulses) { // TODO: Find the size of cache and make it into an array in the parameters list return (pulses == 0) ? 0 : cache[pulses] + 1; } static inline void celt_normalize_residual(const int * restrict iy, float * restrict X, int N, float g) { int i; for (i = 0; i < N; i++) X[i] = g * iy[i]; } static void celt_exp_rotation1(float *X, unsigned int len, unsigned int stride, float c, float s) { float *Xptr; int i; Xptr = X; for (i = 0; i < len - stride; i++) { float x1, x2; x1 = Xptr[0]; x2 = Xptr[stride]; Xptr[stride] = c * x2 + s * x1; *Xptr++ = c * x1 - s * x2; } Xptr = &X[len - 2 * stride - 1]; for (i = len - 2 * stride - 1; i >= 0; i--) { float x1, x2; x1 = Xptr[0]; x2 = Xptr[stride]; Xptr[stride] = c * x2 + s * x1; *Xptr-- = c * x1 - s * x2; } } static inline void celt_exp_rotation(float *X, unsigned int len, unsigned int stride, unsigned int K, enum CeltSpread spread) { unsigned int stride2 = 0; float c, s; float gain, theta; int i; if (2*K >= len || spread == CELT_SPREAD_NONE) return; gain = (float)len / (len + (20 - 5*spread) * K); theta = M_PI * gain * gain / 4; c = cos(theta); s = sin(theta); if (len >= stride << 3) { stride2 = 1; /* This is just a simple (equivalent) way of computing sqrt(len/stride) with rounding. It's basically incrementing long as (stride2+0.5)^2 < len/stride. */ while ((stride2 * stride2 + stride2) * stride + (stride >> 2) < len) stride2++; } /*NOTE: As a minor optimization, we could be passing around log2(B), not B, for both this and for extract_collapse_mask().*/ len /= stride; for (i = 0; i < stride; i++) { if (stride2) celt_exp_rotation1(X + i * len, len, stride2, s, c); celt_exp_rotation1(X + i * len, len, 1, c, s); } } static inline unsigned int celt_extract_collapse_mask(const int *iy, unsigned int N, unsigned int B) { unsigned int collapse_mask; int N0; int i, j; if (B <= 1) return 1; /*NOTE: As a minor optimization, we could be passing around log2(B), not B, for both this and for exp_rotation().*/ N0 = N/B; collapse_mask = 0; for (i = 0; i < B; i++) for (j = 0; j < N0; j++) collapse_mask |= (iy[i*N0+j]!=0)<>= 1; for (i = 0; i < stride; i++) { for (j = 0; j < N0; j++) { float x0 = X[stride * (2 * j + 0) + i]; float x1 = X[stride * (2 * j + 1) + i]; X[stride * (2 * j + 0) + i] = (x0 + x1) * M_SQRT1_2; X[stride * (2 * j + 1) + i] = (x0 - x1) * M_SQRT1_2; } } } static inline int celt_compute_qn(int N, int b, int offset, int pulse_cap, int dualstereo) { int qn, qb; int N2 = 2 * N - 1; if (dualstereo && N == 2) N2--; /* The upper limit ensures that in a stereo split with itheta==16384, we'll * always have enough bits left over to code at least one pulse in the * side; otherwise it would collapse, since it doesn't get folded. */ qb = FFMIN3(b - pulse_cap - (4 << 3), (b + N2 * offset) / N2, 8 << 3); qn = (qb < (1 << 3 >> 1)) ? 1 : ((celt_qn_exp2[qb & 0x7] >> (14 - (qb >> 3))) + 1) >> 1 << 1; return qn; } // this code was adapted from libopus static inline uint64_t celt_cwrsi(unsigned int N, unsigned int K, unsigned int i, int *y) { uint64_t norm = 0; uint32_t p; int s, val; int k0; while (N > 2) { uint32_t q; /*Lots of pulses case:*/ if (K >= N) { const uint32_t *row = celt_pvq_u_row[N]; /* Are the pulses in this dimension negative? */ p = row[K + 1]; s = -(i >= p); i -= p & s; /*Count how many pulses were placed in this dimension.*/ k0 = K; q = row[N]; if (q > i) { K = N; do { p = celt_pvq_u_row[--K][N]; } while (p > i); } else for (p = row[K]; p > i; p = row[K]) K--; i -= p; val = (k0 - K + s) ^ s; norm += val * val; *y++ = val; } else { /*Lots of dimensions case:*/ /*Are there any pulses in this dimension at all?*/ p = celt_pvq_u_row[K ][N]; q = celt_pvq_u_row[K + 1][N]; if (p <= i && i < q) { i -= p; *y++ = 0; } else { /*Are the pulses in this dimension negative?*/ s = -(i >= q); i -= q & s; /*Count how many pulses were placed in this dimension.*/ k0 = K; do p = celt_pvq_u_row[--K][N]; while (p > i); i -= p; val = (k0 - K + s) ^ s; norm += val * val; *y++ = val; } } N--; } /* N == 2 */ p = 2 * K + 1; s = -(i >= p); i -= p & s; k0 = K; K = (i + 1) / 2; if (K) i -= 2 * K - 1; val = (k0 - K + s) ^ s; norm += val * val; *y++ = val; /* N==1 */ s = -i; val = (K + s) ^ s; norm += val * val; *y = val; return norm; } static inline float celt_decode_pulses(OpusRangeCoder *rc, int *y, unsigned int N, unsigned int K) { unsigned int idx; #define CELT_PVQ_U(n, k) (celt_pvq_u_row[FFMIN(n, k)][FFMAX(n, k)]) #define CELT_PVQ_V(n, k) (CELT_PVQ_U(n, k) + CELT_PVQ_U(n, k + 1)) idx = opus_rc_unimodel(rc, CELT_PVQ_V(N, K)); return celt_cwrsi(N, K, idx, y); } /** Decode pulse vector and combine the result with the pitch vector to produce the final normalised signal in the current band. */ static inline unsigned int celt_alg_unquant(OpusRangeCoder *rc, float *X, unsigned int N, unsigned int K, enum CeltSpread spread, unsigned int blocks, float gain) { int y[176]; gain /= sqrtf(celt_decode_pulses(rc, y, N, K)); celt_normalize_residual(y, X, N, gain); celt_exp_rotation(X, N, blocks, K, spread); return celt_extract_collapse_mask(y, N, blocks); } static unsigned int celt_decode_band(CeltContext *s, OpusRangeCoder *rc, const int band, float *X, float *Y, int N, int b, unsigned int blocks, float *lowband, int duration, float *lowband_out, int level, float gain, float *lowband_scratch, int fill) { const uint8_t *cache; int dualstereo, split; int imid = 0, iside = 0; unsigned int N0 = N; int N_B; int N_B0; int B0 = blocks; int time_divide = 0; int recombine = 0; int inv = 0; float mid = 0, side = 0; int longblocks = (B0 == 1); unsigned int cm = 0; N_B0 = N_B = N / blocks; split = dualstereo = (Y != NULL); if (N == 1) { /* special case for one sample */ int i; float *x = X; for (i = 0; i <= dualstereo; i++) { int sign = 0; if (s->remaining2 >= 1<<3) { sign = opus_getrawbits(rc, 1); s->remaining2 -= 1 << 3; b -= 1 << 3; } x[0] = sign ? -1.0f : 1.0f; x = Y; } if (lowband_out) lowband_out[0] = X[0]; return 1; } if (!dualstereo && level == 0) { int tf_change = s->tf_change[band]; int k; if (tf_change > 0) recombine = tf_change; /* Band recombining to increase frequency resolution */ if (lowband && (recombine || ((N_B & 1) == 0 && tf_change < 0) || B0 > 1)) { int j; for (j = 0; j < N; j++) lowband_scratch[j] = lowband[j]; lowband = lowband_scratch; } for (k = 0; k < recombine; k++) { if (lowband) celt_haar1(lowband, N >> k, 1 << k); fill = celt_bit_interleave[fill & 0xF] | celt_bit_interleave[fill >> 4] << 2; } blocks >>= recombine; N_B <<= recombine; /* Increasing the time resolution */ while ((N_B & 1) == 0 && tf_change < 0) { if (lowband) celt_haar1(lowband, N_B, blocks); fill |= fill << blocks; blocks <<= 1; N_B >>= 1; time_divide++; tf_change++; } B0 = blocks; N_B0 = N_B; /* Reorganize the samples in time order instead of frequency order */ if (B0 > 1 && lowband) celt_deinterleave_hadamard(s->scratch, lowband, N_B >> recombine, B0 << recombine, longblocks); } /* If we need 1.5 more bit than we can produce, split the band in two. */ cache = celt_cache_bits + celt_cache_index[(duration + 1) * CELT_MAX_BANDS + band]; if (!dualstereo && duration >= 0 && b > cache[cache[0]] + 12 && N > 2) { N >>= 1; Y = X + N; split = 1; duration -= 1; if (blocks == 1) fill = (fill & 1) | (fill << 1); blocks = (blocks + 1) >> 1; } if (split) { int qn; int itheta = 0; int mbits, sbits, delta; int qalloc; int pulse_cap; int offset; int orig_fill; int tell; /* Decide on the resolution to give to the split parameter theta */ pulse_cap = celt_log_freq_range[band] + duration * 8; offset = (pulse_cap >> 1) - (dualstereo && N == 2 ? CELT_QTHETA_OFFSET_TWOPHASE : CELT_QTHETA_OFFSET); qn = (dualstereo && band >= s->intensitystereo) ? 1 : celt_compute_qn(N, b, offset, pulse_cap, dualstereo); tell = opus_rc_tell_frac(rc); if (qn != 1) { /* Entropy coding of the angle. We use a uniform pdf for the time split, a step for stereo, and a triangular one for the rest. */ if (dualstereo && N > 2) itheta = opus_rc_stepmodel(rc, qn/2); else if (dualstereo || B0 > 1) itheta = opus_rc_unimodel(rc, qn+1); else itheta = opus_rc_trimodel(rc, qn); itheta = itheta * 16384 / qn; /* NOTE: Renormalising X and Y *may* help fixed-point a bit at very high rate. Let's do that at higher complexity */ } else if (dualstereo) { inv = (b > 2 << 3 && s->remaining2 > 2 << 3) ? opus_rc_p2model(rc, 2) : 0; itheta = 0; } qalloc = opus_rc_tell_frac(rc) - tell; b -= qalloc; orig_fill = fill; if (itheta == 0) { imid = 32767; iside = 0; fill &= (1 << blocks) - 1; delta = -16384; } else if (itheta == 16384) { imid = 0; iside = 32767; fill &= ((1 << blocks) - 1) << blocks; delta = 16384; } else { imid = celt_cos(itheta); iside = celt_cos(16384-itheta); /* This is the mid vs side allocation that minimizes squared error in that band. */ delta = ROUND_MUL16((N - 1) << 7, celt_log2tan(iside, imid)); } mid = imid / 32768.0f; side = iside / 32768.0f; /* This is a special case for N=2 that only works for stereo and takes advantage of the fact that mid and side are orthogonal to encode the side with just one bit. */ if (N == 2 && dualstereo) { int c; int sign = 0; float tmp; float *x2, *y2; mbits = b; /* Only need one bit for the side */ sbits = (itheta != 0 && itheta != 16384) ? 1 << 3 : 0; mbits -= sbits; c = (itheta > 8192); s->remaining2 -= qalloc+sbits; x2 = c ? Y : X; y2 = c ? X : Y; if (sbits) sign = opus_getrawbits(rc, 1); sign = 1 - 2 * sign; /* We use orig_fill here because we want to fold the side, but if itheta==16384, we'll have cleared the low bits of fill. */ cm = celt_decode_band(s, rc, band, x2, NULL, N, mbits, blocks, lowband, duration, lowband_out, level, gain, lowband_scratch, orig_fill); /* We don't split N=2 bands, so cm is either 1 or 0 (for a fold-collapse), and there's no need to worry about mixing with the other channel. */ y2[0] = -sign * x2[1]; y2[1] = sign * x2[0]; X[0] *= mid; X[1] *= mid; Y[0] *= side; Y[1] *= side; tmp = X[0]; X[0] = tmp - Y[0]; Y[0] = tmp + Y[0]; tmp = X[1]; X[1] = tmp - Y[1]; Y[1] = tmp + Y[1]; } else { /* "Normal" split code */ float *next_lowband2 = NULL; float *next_lowband_out1 = NULL; int next_level = 0; int rebalance; /* Give more bits to low-energy MDCTs than they would * otherwise deserve */ if (B0 > 1 && !dualstereo && (itheta & 0x3fff)) { if (itheta > 8192) /* Rough approximation for pre-echo masking */ delta -= delta >> (4 - duration); else /* Corresponds to a forward-masking slope of * 1.5 dB per 10 ms */ delta = FFMIN(0, delta + (N << 3 >> (5 - duration))); } mbits = av_clip((b - delta) / 2, 0, b); sbits = b - mbits; s->remaining2 -= qalloc; if (lowband && !dualstereo) next_lowband2 = lowband + N; /* >32-bit split case */ /* Only stereo needs to pass on lowband_out. * Otherwise, it's handled at the end */ if (dualstereo) next_lowband_out1 = lowband_out; else next_level = level + 1; rebalance = s->remaining2; if (mbits >= sbits) { /* In stereo mode, we do not apply a scaling to the mid * because we need the normalized mid for folding later */ cm = celt_decode_band(s, rc, band, X, NULL, N, mbits, blocks, lowband, duration, next_lowband_out1, next_level, dualstereo ? 1.0f : (gain * mid), lowband_scratch, fill); rebalance = mbits - (rebalance - s->remaining2); if (rebalance > 3 << 3 && itheta != 0) sbits += rebalance - (3 << 3); /* For a stereo split, the high bits of fill are always zero, * so no folding will be done to the side. */ cm |= celt_decode_band(s, rc, band, Y, NULL, N, sbits, blocks, next_lowband2, duration, NULL, next_level, gain * side, NULL, fill >> blocks) << ((B0 >> 1) & (dualstereo - 1)); } else { /* For a stereo split, the high bits of fill are always zero, * so no folding will be done to the side. */ cm = celt_decode_band(s, rc, band, Y, NULL, N, sbits, blocks, next_lowband2, duration, NULL, next_level, gain * side, NULL, fill >> blocks) << ((B0 >> 1) & (dualstereo - 1)); rebalance = sbits - (rebalance - s->remaining2); if (rebalance > 3 << 3 && itheta != 16384) mbits += rebalance - (3 << 3); /* In stereo mode, we do not apply a scaling to the mid because * we need the normalized mid for folding later */ cm |= celt_decode_band(s, rc, band, X, NULL, N, mbits, blocks, lowband, duration, next_lowband_out1, next_level, dualstereo ? 1.0f : (gain * mid), lowband_scratch, fill); } } } else { /* This is the basic no-split case */ unsigned int q = celt_bits2pulses(cache, b); unsigned int curr_bits = celt_pulses2bits(cache, q); s->remaining2 -= curr_bits; /* Ensures we can never bust the budget */ while (s->remaining2 < 0 && q > 0) { s->remaining2 += curr_bits; curr_bits = celt_pulses2bits(cache, --q); s->remaining2 -= curr_bits; } if (q != 0) { /* Finally do the actual quantization */ cm = celt_alg_unquant(rc, X, N, (q < 8) ? q : (8 + (q & 7)) << ((q >> 3) - 1), s->spread, blocks, gain); } else { /* If there's no pulse, fill the band anyway */ int j; unsigned int cm_mask = (1 << blocks) - 1; fill &= cm_mask; if (!fill) { for (j = 0; j < N; j++) X[j] = 0.0f; } else { if (!lowband) { /* Noise */ for (j = 0; j < N; j++) X[j] = (((int32_t)celt_rng(s)) >> 20); cm = cm_mask; } else { /* Folded spectrum */ for (j = 0; j < N; j++) { /* About 48 dB below the "normal" folding level */ X[j] = lowband[j] + (((celt_rng(s)) & 0x8000) ? 1.0f / 256 : -1.0f / 256); } cm = fill; } celt_renormalize_vector(X, N, gain); } } } /* This code is used by the decoder and by the resynthesis-enabled encoder */ if (dualstereo) { int j; if (N != 2) celt_stereo_merge(X, Y, mid, N); if (inv) { for (j = 0; j < N; j++) Y[j] *= -1; } } else if (level == 0) { int k; /* Undo the sample reorganization going from time order to frequency order */ if (B0 > 1) celt_interleave_hadamard(s->scratch, X, N_B>>recombine, B0<>= 1; N_B <<= 1; cm |= cm >> blocks; celt_haar1(X, N_B, blocks); } for (k = 0; k < recombine; k++) { cm = celt_bit_deinterleave[cm]; celt_haar1(X, N0>>k, 1<startband; i < s->endband; i++) { float *dst = data + (celt_freq_bands[i] << s->duration); float norm = pow(2, frame->energy[i] + celt_mean_energy[i]); for (j = 0; j < celt_freq_range[i] << s->duration; j++) dst[j] *= norm; } } static void celt_postfilter_apply_transition(CeltFrame *frame, float *data) { const int T0 = frame->pf_period_old; const int T1 = frame->pf_period; float g00, g01, g02; float g10, g11, g12; float x0, x1, x2, x3, x4; int i; if (frame->pf_gains[0] == 0.0 && frame->pf_gains_old[0] == 0.0) return; g00 = frame->pf_gains_old[0]; g01 = frame->pf_gains_old[1]; g02 = frame->pf_gains_old[2]; g10 = frame->pf_gains[0]; g11 = frame->pf_gains[1]; g12 = frame->pf_gains[2]; x1 = data[-T1 + 1]; x2 = data[-T1]; x3 = data[-T1 - 1]; x4 = data[-T1 - 2]; for (i = 0; i < CELT_OVERLAP; i++) { float w = ff_celt_window2[i]; x0 = data[i - T1 + 2]; data[i] += (1.0 - w) * g00 * data[i - T0] + (1.0 - w) * g01 * (data[i - T0 - 1] + data[i - T0 + 1]) + (1.0 - w) * g02 * (data[i - T0 - 2] + data[i - T0 + 2]) + w * g10 * x2 + w * g11 * (x1 + x3) + w * g12 * (x0 + x4); x4 = x3; x3 = x2; x2 = x1; x1 = x0; } } static void celt_postfilter_apply(CeltFrame *frame, float *data, int len) { const int T = frame->pf_period; float g0, g1, g2; float x0, x1, x2, x3, x4; int i; if (frame->pf_gains[0] == 0.0 || len <= 0) return; g0 = frame->pf_gains[0]; g1 = frame->pf_gains[1]; g2 = frame->pf_gains[2]; x4 = data[-T - 2]; x3 = data[-T - 1]; x2 = data[-T]; x1 = data[-T + 1]; for (i = 0; i < len; i++) { x0 = data[i - T + 2]; data[i] += g0 * x2 + g1 * (x1 + x3) + g2 * (x0 + x4); x4 = x3; x3 = x2; x2 = x1; x1 = x0; } } static void celt_postfilter(CeltContext *s, CeltFrame *frame) { int len = s->blocksize * s->blocks; celt_postfilter_apply_transition(frame, frame->buf + 1024); frame->pf_period_old = frame->pf_period; memcpy(frame->pf_gains_old, frame->pf_gains, sizeof(frame->pf_gains)); frame->pf_period = frame->pf_period_new; memcpy(frame->pf_gains, frame->pf_gains_new, sizeof(frame->pf_gains)); if (len > CELT_OVERLAP) { celt_postfilter_apply_transition(frame, frame->buf + 1024 + CELT_OVERLAP); celt_postfilter_apply(frame, frame->buf + 1024 + 2 * CELT_OVERLAP, len - 2 * CELT_OVERLAP); frame->pf_period_old = frame->pf_period; memcpy(frame->pf_gains_old, frame->pf_gains, sizeof(frame->pf_gains)); } memmove(frame->buf, frame->buf + len, (1024 + CELT_OVERLAP / 2) * sizeof(float)); } static int parse_postfilter(CeltContext *s, OpusRangeCoder *rc, int consumed) { static const float postfilter_taps[3][3] = { { 0.3066406250f, 0.2170410156f, 0.1296386719f }, { 0.4638671875f, 0.2680664062f, 0.0 }, { 0.7998046875f, 0.1000976562f, 0.0 } }; int i; memset(s->frame[0].pf_gains_new, 0, sizeof(s->frame[0].pf_gains_new)); memset(s->frame[1].pf_gains_new, 0, sizeof(s->frame[1].pf_gains_new)); if (s->startband == 0 && consumed + 16 <= s->framebits) { int has_postfilter = opus_rc_p2model(rc, 1); if (has_postfilter) { float gain; int tapset, octave, period; octave = opus_rc_unimodel(rc, 6); period = (16 << octave) + opus_getrawbits(rc, 4 + octave) - 1; gain = 0.09375f * (opus_getrawbits(rc, 3) + 1); tapset = (opus_rc_tell(rc) + 2 <= s->framebits) ? opus_rc_getsymbol(rc, celt_model_tapset) : 0; for (i = 0; i < 2; i++) { CeltFrame *frame = &s->frame[i]; frame->pf_period_new = FFMAX(period, CELT_POSTFILTER_MINPERIOD); frame->pf_gains_new[0] = gain * postfilter_taps[tapset][0]; frame->pf_gains_new[1] = gain * postfilter_taps[tapset][1]; frame->pf_gains_new[2] = gain * postfilter_taps[tapset][2]; } } consumed = opus_rc_tell(rc); } return consumed; } static void process_anticollapse(CeltContext *s, CeltFrame *frame, float *X) { int i, j, k; for (i = s->startband; i < s->endband; i++) { int renormalize = 0; float *xptr; float prev[2]; float Ediff, r; float thresh, sqrt_1; int depth; /* depth in 1/8 bits */ depth = (1 + s->pulses[i]) / (celt_freq_range[i] << s->duration); thresh = pow(2, -1.0 - 0.125f * depth); sqrt_1 = 1.0f / sqrtf(celt_freq_range[i] << s->duration); xptr = X + (celt_freq_bands[i] << s->duration); prev[0] = frame->prev_energy[0][i]; prev[1] = frame->prev_energy[1][i]; if (s->coded_channels == 1) { CeltFrame *frame1 = &s->frame[1]; prev[0] = FFMAX(prev[0], frame1->prev_energy[0][i]); prev[1] = FFMAX(prev[1], frame1->prev_energy[1][i]); } Ediff = frame->energy[i] - FFMIN(prev[0], prev[1]); Ediff = FFMAX(0, Ediff); /* r needs to be multiplied by 2 or 2*sqrt(2) depending on LM because short blocks don't have the same energy as long */ r = pow(2, 1 - Ediff); if (s->duration == 3) r *= M_SQRT2; r = FFMIN(thresh, r) * sqrt_1; for (k = 0; k < 1 << s->duration; k++) { /* Detect collapse */ if (!(frame->collapse_masks[i] & 1 << k)) { /* Fill with noise */ for (j = 0; j < celt_freq_range[i]; j++) xptr[(j << s->duration) + k] = (celt_rng(s) & 0x8000) ? r : -r; renormalize = 1; } } /* We just added some energy, so we need to renormalize */ if (renormalize) celt_renormalize_vector(xptr, celt_freq_range[i] << s->duration, 1.0f); } } static void celt_decode_bands(CeltContext *s, OpusRangeCoder *rc) { float lowband_scratch[8 * 22]; float norm[2 * 8 * 100]; int totalbits = (s->framebits << 3) - s->anticollapse_bit; int update_lowband = 1; int lowband_offset = 0; int i, j; memset(s->coeffs, 0, sizeof(s->coeffs)); for (i = s->startband; i < s->endband; i++) { int band_offset = celt_freq_bands[i] << s->duration; int band_size = celt_freq_range[i] << s->duration; float *X = s->coeffs[0] + band_offset; float *Y = (s->coded_channels == 2) ? s->coeffs[1] + band_offset : NULL; int consumed = opus_rc_tell_frac(rc); float *norm2 = norm + 8 * 100; int effective_lowband = -1; unsigned int cm[2]; int b; /* Compute how many bits we want to allocate to this band */ if (i != s->startband) s->remaining -= consumed; s->remaining2 = totalbits - consumed - 1; if (i <= s->codedbands - 1) { int curr_balance = s->remaining / FFMIN(3, s->codedbands-i); b = av_clip_uintp2(FFMIN(s->remaining2 + 1, s->pulses[i] + curr_balance), 14); } else b = 0; if (celt_freq_bands[i] - celt_freq_range[i] >= celt_freq_bands[s->startband] && (update_lowband || lowband_offset == 0)) lowband_offset = i; /* Get a conservative estimate of the collapse_mask's for the bands we're going to be folding from. */ if (lowband_offset != 0 && (s->spread != CELT_SPREAD_AGGRESSIVE || s->blocks > 1 || s->tf_change[i] < 0)) { int foldstart, foldend; /* This ensures we never repeat spectral content within one band */ effective_lowband = FFMAX(celt_freq_bands[s->startband], celt_freq_bands[lowband_offset] - celt_freq_range[i]); foldstart = lowband_offset; while (celt_freq_bands[--foldstart] > effective_lowband); foldend = lowband_offset - 1; while (celt_freq_bands[++foldend] < effective_lowband + celt_freq_range[i]); cm[0] = cm[1] = 0; for (j = foldstart; j < foldend; j++) { cm[0] |= s->frame[0].collapse_masks[j]; cm[1] |= s->frame[s->coded_channels - 1].collapse_masks[j]; } } else /* Otherwise, we'll be using the LCG to fold, so all blocks will (almost always) be non-zero.*/ cm[0] = cm[1] = (1 << s->blocks) - 1; if (s->dualstereo && i == s->intensitystereo) { /* Switch off dual stereo to do intensity */ s->dualstereo = 0; for (j = celt_freq_bands[s->startband] << s->duration; j < band_offset; j++) norm[j] = (norm[j] + norm2[j]) / 2; } if (s->dualstereo) { cm[0] = celt_decode_band(s, rc, i, X, NULL, band_size, b / 2, s->blocks, effective_lowband != -1 ? norm + (effective_lowband << s->duration) : NULL, s->duration, norm + band_offset, 0, 1.0f, lowband_scratch, cm[0]); cm[1] = celt_decode_band(s, rc, i, Y, NULL, band_size, b/2, s->blocks, effective_lowband != -1 ? norm2 + (effective_lowband << s->duration) : NULL, s->duration, norm2 + band_offset, 0, 1.0f, lowband_scratch, cm[1]); } else { cm[0] = celt_decode_band(s, rc, i, X, Y, band_size, b, s->blocks, effective_lowband != -1 ? norm + (effective_lowband << s->duration) : NULL, s->duration, norm + band_offset, 0, 1.0f, lowband_scratch, cm[0]|cm[1]); cm[1] = cm[0]; } s->frame[0].collapse_masks[i] = (uint8_t)cm[0]; s->frame[s->coded_channels - 1].collapse_masks[i] = (uint8_t)cm[1]; s->remaining += s->pulses[i] + consumed; /* Update the folding position only as long as we have 1 bit/sample depth */ update_lowband = (b > band_size << 3); } } int ff_celt_decode_frame(CeltContext *s, OpusRangeCoder *rc, float **output, int coded_channels, int frame_size, int startband, int endband) { int i, j; int consumed; // bits of entropy consumed thus far for this frame int silence = 0; int transient = 0; int anticollapse = 0; IMDCT15Context *imdct; float imdct_scale = 1.0; if (coded_channels != 1 && coded_channels != 2) { av_log(s->avctx, AV_LOG_ERROR, "Invalid number of coded channels: %d\n", coded_channels); return AVERROR_INVALIDDATA; } if (startband < 0 || startband > endband || endband > CELT_MAX_BANDS) { av_log(s->avctx, AV_LOG_ERROR, "Invalid start/end band: %d %d\n", startband, endband); return AVERROR_INVALIDDATA; } s->flushed = 0; s->coded_channels = coded_channels; s->startband = startband; s->endband = endband; s->framebits = rc->rb.bytes * 8; s->duration = av_log2(frame_size / CELT_SHORT_BLOCKSIZE); if (s->duration > CELT_MAX_LOG_BLOCKS || frame_size != CELT_SHORT_BLOCKSIZE * (1 << s->duration)) { av_log(s->avctx, AV_LOG_ERROR, "Invalid CELT frame size: %d\n", frame_size); return AVERROR_INVALIDDATA; } if (!s->output_channels) s->output_channels = coded_channels; memset(s->frame[0].collapse_masks, 0, sizeof(s->frame[0].collapse_masks)); memset(s->frame[1].collapse_masks, 0, sizeof(s->frame[1].collapse_masks)); consumed = opus_rc_tell(rc); /* obtain silence flag */ if (consumed >= s->framebits) silence = 1; else if (consumed == 1) silence = opus_rc_p2model(rc, 15); if (silence) { consumed = s->framebits; rc->total_read_bits += s->framebits - opus_rc_tell(rc); } /* obtain post-filter options */ consumed = parse_postfilter(s, rc, consumed); /* obtain transient flag */ if (s->duration != 0 && consumed+3 <= s->framebits) transient = opus_rc_p2model(rc, 3); s->blocks = transient ? 1 << s->duration : 1; s->blocksize = frame_size / s->blocks; imdct = s->imdct[transient ? 0 : s->duration]; if (coded_channels == 1) { for (i = 0; i < CELT_MAX_BANDS; i++) s->frame[0].energy[i] = FFMAX(s->frame[0].energy[i], s->frame[1].energy[i]); } celt_decode_coarse_energy(s, rc); celt_decode_tf_changes (s, rc, transient); celt_decode_allocation (s, rc); celt_decode_fine_energy (s, rc); celt_decode_bands (s, rc); if (s->anticollapse_bit) anticollapse = opus_getrawbits(rc, 1); celt_decode_final_energy(s, rc, s->framebits - opus_rc_tell(rc)); /* apply anti-collapse processing and denormalization to * each coded channel */ for (i = 0; i < s->coded_channels; i++) { CeltFrame *frame = &s->frame[i]; if (anticollapse) process_anticollapse(s, frame, s->coeffs[i]); celt_denormalize(s, frame, s->coeffs[i]); } /* stereo -> mono downmix */ if (s->output_channels < s->coded_channels) { s->dsp.vector_fmac_scalar(s->coeffs[0], s->coeffs[1], 1.0, FFALIGN(frame_size, 16)); imdct_scale = 0.5; } else if (s->output_channels > s->coded_channels) memcpy(s->coeffs[1], s->coeffs[0], frame_size * sizeof(float)); if (silence) { for (i = 0; i < 2; i++) { CeltFrame *frame = &s->frame[i]; for (j = 0; j < FF_ARRAY_ELEMS(frame->energy); j++) frame->energy[j] = CELT_ENERGY_SILENCE; } memset(s->coeffs, 0, sizeof(s->coeffs)); } /* transform and output for each output channel */ for (i = 0; i < s->output_channels; i++) { CeltFrame *frame = &s->frame[i]; float m = frame->deemph_coeff; /* iMDCT and overlap-add */ for (j = 0; j < s->blocks; j++) { float *dst = frame->buf + 1024 + j * s->blocksize; imdct->imdct_half(imdct, dst + CELT_OVERLAP / 2, s->coeffs[i] + j, s->blocks, imdct_scale); s->dsp.vector_fmul_window(dst, dst, dst + CELT_OVERLAP / 2, celt_window, CELT_OVERLAP / 2); } /* postfilter */ celt_postfilter(s, frame); /* deemphasis and output scaling */ for (j = 0; j < frame_size; j++) { float tmp = frame->buf[1024 - frame_size + j] + m; m = tmp * CELT_DEEMPH_COEFF; output[i][j] = tmp / 32768.; } frame->deemph_coeff = m; } if (coded_channels == 1) memcpy(s->frame[1].energy, s->frame[0].energy, sizeof(s->frame[0].energy)); for (i = 0; i < 2; i++ ) { CeltFrame *frame = &s->frame[i]; if (!transient) { memcpy(frame->prev_energy[1], frame->prev_energy[0], sizeof(frame->prev_energy[0])); memcpy(frame->prev_energy[0], frame->energy, sizeof(frame->prev_energy[0])); } else { for (j = 0; j < CELT_MAX_BANDS; j++) frame->prev_energy[0][j] = FFMIN(frame->prev_energy[0][j], frame->energy[j]); } for (j = 0; j < s->startband; j++) { frame->prev_energy[0][j] = CELT_ENERGY_SILENCE; frame->energy[j] = 0.0; } for (j = s->endband; j < CELT_MAX_BANDS; j++) { frame->prev_energy[0][j] = CELT_ENERGY_SILENCE; frame->energy[j] = 0.0; } } s->seed = rc->range; return 0; } void ff_celt_flush(CeltContext *s) { int i, j; if (s->flushed) return; for (i = 0; i < 2; i++) { CeltFrame *frame = &s->frame[i]; for (j = 0; j < CELT_MAX_BANDS; j++) frame->prev_energy[0][j] = frame->prev_energy[1][j] = CELT_ENERGY_SILENCE; memset(frame->energy, 0, sizeof(frame->energy)); memset(frame->buf, 0, sizeof(frame->buf)); memset(frame->pf_gains, 0, sizeof(frame->pf_gains)); memset(frame->pf_gains_old, 0, sizeof(frame->pf_gains_old)); memset(frame->pf_gains_new, 0, sizeof(frame->pf_gains_new)); frame->deemph_coeff = 0.0; } s->seed = 0; s->flushed = 1; } void ff_celt_free(CeltContext **ps) { CeltContext *s = *ps; int i; if (!s) return; for (i = 0; i < FF_ARRAY_ELEMS(s->imdct); i++) ff_imdct15_uninit(&s->imdct[i]); av_freep(ps); } int ff_celt_init(AVCodecContext *avctx, CeltContext **ps, int output_channels) { CeltContext *s; int i, ret; if (output_channels != 1 && output_channels != 2) { av_log(avctx, AV_LOG_ERROR, "Invalid number of output channels: %d\n", output_channels); return AVERROR(EINVAL); } s = av_mallocz(sizeof(*s)); if (!s) return AVERROR(ENOMEM); s->avctx = avctx; s->output_channels = output_channels; for (i = 0; i < FF_ARRAY_ELEMS(s->imdct); i++) { ret = ff_imdct15_init(&s->imdct[i], i + 3); if (ret < 0) goto fail; } avpriv_float_dsp_init(&s->dsp, avctx->flags & AV_CODEC_FLAG_BITEXACT); ff_celt_flush(s); *ps = s; return 0; fail: ff_celt_free(&s); return ret; }