The Tor Browser: media/libopus/celt/celt_decoder.c@6474c204b198 (annotated)

media/libopus/celt/celt_decoder.c@6474c204b198 (annotated)

media/libopus/celt/celt_decoder.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* Copyright (c) 2007-2008 CSIRO
    Copyright (c) 2007-2010 Xiph.Org Foundation
    Copyright (c) 2008 Gregory Maxwell
    Written by Jean-Marc Valin and Gregory Maxwell */
 /*
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:
    - Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
    - Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 #define CELT_DECODER_C
 #include "cpu_support.h"
 #include "os_support.h"
 #include "mdct.h"
 #include <math.h>
 #include "celt.h"
 #include "pitch.h"
 #include "bands.h"
 #include "modes.h"
 #include "entcode.h"
 #include "quant_bands.h"
 #include "rate.h"
 #include "stack_alloc.h"
 #include "mathops.h"
 #include "float_cast.h"
 #include <stdarg.h>
 #include "celt_lpc.h"
 #include "vq.h"
 /**********************************************************************/
 /*                                                                    */
 /*                             DECODER                                */
 /*                                                                    */
 /**********************************************************************/
 #define DECODE_BUFFER_SIZE 2048
 /** Decoder state
  @brief Decoder state
  */
 struct OpusCustomDecoder {
    const OpusCustomMode *mode;
    int overlap;
    int channels;
    int stream_channels;
    int downsample;
    int start, end;
    int signalling;
    int arch;
    /* Everything beyond this point gets cleared on a reset */
 #define DECODER_RESET_START rng
    opus_uint32 rng;
    int error;
    int last_pitch_index;
    int loss_count;
    int postfilter_period;
    int postfilter_period_old;
    opus_val16 postfilter_gain;
    opus_val16 postfilter_gain_old;
    int postfilter_tapset;
    int postfilter_tapset_old;
    celt_sig preemph_memD[2];
    celt_sig _decode_mem[1]; /* Size = channels*(DECODE_BUFFER_SIZE+mode->overlap) */
    /* opus_val16 lpc[],  Size = channels*LPC_ORDER */
    /* opus_val16 oldEBands[], Size = 2*mode->nbEBands */
    /* opus_val16 oldLogE[], Size = 2*mode->nbEBands */
    /* opus_val16 oldLogE2[], Size = 2*mode->nbEBands */
    /* opus_val16 backgroundLogE[], Size = 2*mode->nbEBands */
 };
 int celt_decoder_get_size(int channels)
 {
    const CELTMode *mode = opus_custom_mode_create(48000, 960, NULL);
    return opus_custom_decoder_get_size(mode, channels);
 }
 OPUS_CUSTOM_NOSTATIC int opus_custom_decoder_get_size(const CELTMode *mode, int channels)
 {
    int size = sizeof(struct CELTDecoder)
             + (channels*(DECODE_BUFFER_SIZE+mode->overlap)-1)*sizeof(celt_sig)
             + channels*LPC_ORDER*sizeof(opus_val16)
             + 4*2*mode->nbEBands*sizeof(opus_val16);
    return size;
 }
 #ifdef CUSTOM_MODES
 CELTDecoder *opus_custom_decoder_create(const CELTMode *mode, int channels, int *error)
 {
    int ret;
    CELTDecoder *st = (CELTDecoder *)opus_alloc(opus_custom_decoder_get_size(mode, channels));
    ret = opus_custom_decoder_init(st, mode, channels);
    if (ret != OPUS_OK)
    {
       opus_custom_decoder_destroy(st);
       st = NULL;
    }
    if (error)
       *error = ret;
    return st;
 }
 #endif /* CUSTOM_MODES */
 int celt_decoder_init(CELTDecoder *st, opus_int32 sampling_rate, int channels)
 {
    int ret;
    ret = opus_custom_decoder_init(st, opus_custom_mode_create(48000, 960, NULL), channels);
    if (ret != OPUS_OK)
       return ret;
    st->downsample = resampling_factor(sampling_rate);
    if (st->downsample==0)
       return OPUS_BAD_ARG;
    else
       return OPUS_OK;
 }
 OPUS_CUSTOM_NOSTATIC int opus_custom_decoder_init(CELTDecoder *st, const CELTMode *mode, int channels)
 {
    if (channels < 0 || channels > 2)
       return OPUS_BAD_ARG;
    if (st==NULL)
       return OPUS_ALLOC_FAIL;
    OPUS_CLEAR((char*)st, opus_custom_decoder_get_size(mode, channels));
    st->mode = mode;
    st->overlap = mode->overlap;
    st->stream_channels = st->channels = channels;
    st->downsample = 1;
    st->start = 0;
    st->end = st->mode->effEBands;
    st->signalling = 1;
    st->arch = opus_select_arch();
    st->loss_count = 0;
    opus_custom_decoder_ctl(st, OPUS_RESET_STATE);
    return OPUS_OK;
 }
 #ifdef CUSTOM_MODES
 void opus_custom_decoder_destroy(CELTDecoder *st)
 {
    opus_free(st);
 }
 #endif /* CUSTOM_MODES */
 static OPUS_INLINE opus_val16 SIG2WORD16(celt_sig x)
 {
 #ifdef FIXED_POINT
    x = PSHR32(x, SIG_SHIFT);
    x = MAX32(x, -32768);
    x = MIN32(x, 32767);
    return EXTRACT16(x);
 #else
    return (opus_val16)x;
 #endif
 }
 #ifndef RESYNTH
 static
 #endif
 void deemphasis(celt_sig *in[], opus_val16 *pcm, int N, int C, int downsample, const opus_val16 *coef, celt_sig *mem, celt_sig * OPUS_RESTRICT scratch)
 {
    int c;
    int Nd;
    int apply_downsampling=0;
    opus_val16 coef0;
    coef0 = coef[0];
    Nd = N/downsample;
    c=0; do {
       int j;
       celt_sig * OPUS_RESTRICT x;
       opus_val16  * OPUS_RESTRICT y;
       celt_sig m = mem[c];
       x =in[c];
       y = pcm+c;
 #ifdef CUSTOM_MODES
       if (coef[1] != 0)
       {
          opus_val16 coef1 = coef[1];
          opus_val16 coef3 = coef[3];
          for (j=0;j<N;j++)
          {
             celt_sig tmp = x[j] + m + VERY_SMALL;
             m = MULT16_32_Q15(coef0, tmp)
                           - MULT16_32_Q15(coef1, x[j]);
             tmp = SHL32(MULT16_32_Q15(coef3, tmp), 2);
             scratch[j] = tmp;
          }
          apply_downsampling=1;
       } else
 #endif
       if (downsample>1)
       {
          /* Shortcut for the standard (non-custom modes) case */
          for (j=0;j<N;j++)
          {
             celt_sig tmp = x[j] + m + VERY_SMALL;
             m = MULT16_32_Q15(coef0, tmp);
             scratch[j] = tmp;
          }
          apply_downsampling=1;
       } else {
          /* Shortcut for the standard (non-custom modes) case */
          for (j=0;j<N;j++)
          {
             celt_sig tmp = x[j] + m + VERY_SMALL;
             m = MULT16_32_Q15(coef0, tmp);
             y[j*C] = SCALEOUT(SIG2WORD16(tmp));
          }
       }
       mem[c] = m;
       if (apply_downsampling)
       {
          /* Perform down-sampling */
          for (j=0;j<Nd;j++)
             y[j*C] = SCALEOUT(SIG2WORD16(scratch[j*downsample]));
       }
    } while (++c<C);
 }
 /** Compute the IMDCT and apply window for all sub-frames and
     all channels in a frame */
 #ifndef RESYNTH
 static
 #endif
 void compute_inv_mdcts(const CELTMode *mode, int shortBlocks, celt_sig *X,
       celt_sig * OPUS_RESTRICT out_mem[], int C, int LM)
 {
    int b, c;
    int B;
    int N;
    int shift;
    const int overlap = OVERLAP(mode);
    if (shortBlocks)
    {
       B = shortBlocks;
       N = mode->shortMdctSize;
       shift = mode->maxLM;
    } else {
       B = 1;
       N = mode->shortMdctSize<<LM;
       shift = mode->maxLM-LM;
    }
    c=0; do {
       /* IMDCT on the interleaved the sub-frames, overlap-add is performed by the IMDCT */
       for (b=0;b<B;b++)
          clt_mdct_backward(&mode->mdct, &X[b+c*N*B], out_mem[c]+N*b, mode->window, overlap, shift, B);
    } while (++c<C);
 }
 static void tf_decode(int start, int end, int isTransient, int *tf_res, int LM, ec_dec *dec)
 {
    int i, curr, tf_select;
    int tf_select_rsv;
    int tf_changed;
    int logp;
    opus_uint32 budget;
    opus_uint32 tell;
    budget = dec->storage*8;
    tell = ec_tell(dec);
    logp = isTransient ? 2 : 4;
    tf_select_rsv = LM>0 && tell+logp+1<=budget;
    budget -= tf_select_rsv;
    tf_changed = curr = 0;
    for (i=start;i<end;i++)
    {
       if (tell+logp<=budget)
       {
          curr ^= ec_dec_bit_logp(dec, logp);
          tell = ec_tell(dec);
          tf_changed |= curr;
       }
       tf_res[i] = curr;
       logp = isTransient ? 4 : 5;
    }
    tf_select = 0;
    if (tf_select_rsv &&
      tf_select_table[LM][4*isTransient+0+tf_changed] !=
      tf_select_table[LM][4*isTransient+2+tf_changed])
    {
       tf_select = ec_dec_bit_logp(dec, 1);
    }
    for (i=start;i<end;i++)
    {
       tf_res[i] = tf_select_table[LM][4*isTransient+2*tf_select+tf_res[i]];
    }
 }
 /* The maximum pitch lag to allow in the pitch-based PLC. It's possible to save
    CPU time in the PLC pitch search by making this smaller than MAX_PERIOD. The
    current value corresponds to a pitch of 66.67 Hz. */
 #define PLC_PITCH_LAG_MAX (720)
 /* The minimum pitch lag to allow in the pitch-based PLC. This corresponds to a
    pitch of 480 Hz. */
 #define PLC_PITCH_LAG_MIN (100)
 static void celt_decode_lost(CELTDecoder * OPUS_RESTRICT st, opus_val16 * OPUS_RESTRICT pcm, int N, int LM)
 {
    int c;
    int i;
    const int C = st->channels;
    celt_sig *decode_mem[2];
    celt_sig *out_syn[2];
    opus_val16 *lpc;
    opus_val16 *oldBandE, *oldLogE, *oldLogE2, *backgroundLogE;
    const OpusCustomMode *mode;
    int nbEBands;
    int overlap;
    int start;
    int downsample;
    int loss_count;
    int noise_based;
    const opus_int16 *eBands;
    VARDECL(celt_sig, scratch);
    SAVE_STACK;
    mode = st->mode;
    nbEBands = mode->nbEBands;
    overlap = mode->overlap;
    eBands = mode->eBands;
    c=0; do {
       decode_mem[c] = st->_decode_mem + c*(DECODE_BUFFER_SIZE+overlap);
       out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
    } while (++c<C);
    lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+overlap)*C);
    oldBandE = lpc+C*LPC_ORDER;
    oldLogE = oldBandE + 2*nbEBands;
    oldLogE2 = oldLogE + 2*nbEBands;
    backgroundLogE = oldLogE2  + 2*nbEBands;
    loss_count = st->loss_count;
    start = st->start;
    downsample = st->downsample;
    noise_based = loss_count >= 5 || start != 0;
    ALLOC(scratch, noise_based?N*C:N, celt_sig);
    if (noise_based)
    {
       /* Noise-based PLC/CNG */
       celt_sig *freq;
       VARDECL(celt_norm, X);
       opus_uint32 seed;
       opus_val16 *plcLogE;
       int end;
       int effEnd;
       end = st->end;
       effEnd = IMAX(start, IMIN(end, mode->effEBands));
       /* Share the interleaved signal MDCT coefficient buffer with the
          deemphasis scratch buffer. */
       freq = scratch;
       ALLOC(X, C*N, celt_norm);   /**< Interleaved normalised MDCTs */
       if (loss_count >= 5)
          plcLogE = backgroundLogE;
       else {
          /* Energy decay */
          opus_val16 decay = loss_count==0 ?
                QCONST16(1.5f, DB_SHIFT) : QCONST16(.5f, DB_SHIFT);
          c=0; do
          {
             for (i=start;i<end;i++)
                oldBandE[c*nbEBands+i] -= decay;
          } while (++c<C);
          plcLogE = oldBandE;
       }
       seed = st->rng;
       for (c=0;c<C;c++)
       {
          for (i=start;i<effEnd;i++)
          {
             int j;
             int boffs;
             int blen;
             boffs = N*c+(eBands[i]<<LM);
             blen = (eBands[i+1]-eBands[i])<<LM;
             for (j=0;j<blen;j++)
             {
                seed = celt_lcg_rand(seed);
                X[boffs+j] = (celt_norm)((opus_int32)seed>>20);
             }
             renormalise_vector(X+boffs, blen, Q15ONE);
          }
       }
       st->rng = seed;
       denormalise_bands(mode, X, freq, plcLogE, start, effEnd, C, 1<<LM);
       c=0; do {
          int bound = eBands[effEnd]<<LM;
          if (downsample!=1)
             bound = IMIN(bound, N/downsample);
          for (i=bound;i<N;i++)
             freq[c*N+i] = 0;
       } while (++c<C);
       c=0; do {
          OPUS_MOVE(decode_mem[c], decode_mem[c]+N,
                DECODE_BUFFER_SIZE-N+(overlap>>1));
       } while (++c<C);
       compute_inv_mdcts(mode, 0, freq, out_syn, C, LM);
    } else {
       /* Pitch-based PLC */
       const opus_val16 *window;
       opus_val16 fade = Q15ONE;
       int pitch_index;
       VARDECL(opus_val32, etmp);
       VARDECL(opus_val16, exc);
       if (loss_count == 0)
       {
          VARDECL( opus_val16, lp_pitch_buf );
          ALLOC( lp_pitch_buf, DECODE_BUFFER_SIZE>>1, opus_val16 );
          pitch_downsample(decode_mem, lp_pitch_buf,
                DECODE_BUFFER_SIZE, C, st->arch);
          pitch_search(lp_pitch_buf+(PLC_PITCH_LAG_MAX>>1), lp_pitch_buf,
                DECODE_BUFFER_SIZE-PLC_PITCH_LAG_MAX,
                PLC_PITCH_LAG_MAX-PLC_PITCH_LAG_MIN, &pitch_index, st->arch);
          pitch_index = PLC_PITCH_LAG_MAX-pitch_index;
          st->last_pitch_index = pitch_index;
       } else {
          pitch_index = st->last_pitch_index;
          fade = QCONST16(.8f,15);
       }
       ALLOC(etmp, overlap, opus_val32);
       ALLOC(exc, MAX_PERIOD, opus_val16);
       window = mode->window;
       c=0; do {
          opus_val16 decay;
          opus_val16 attenuation;
          opus_val32 S1=0;
          celt_sig *buf;
          int extrapolation_offset;
          int extrapolation_len;
          int exc_length;
          int j;
          buf = decode_mem[c];
          for (i=0;i<MAX_PERIOD;i++) {
             exc[i] = ROUND16(buf[DECODE_BUFFER_SIZE-MAX_PERIOD+i], SIG_SHIFT);
          }
          if (loss_count == 0)
          {
             opus_val32 ac[LPC_ORDER+1];
             /* Compute LPC coefficients for the last MAX_PERIOD samples before
                the first loss so we can work in the excitation-filter domain. */
             _celt_autocorr(exc, ac, window, overlap,
                    LPC_ORDER, MAX_PERIOD, st->arch);
             /* Add a noise floor of -40 dB. */
 #ifdef FIXED_POINT
             ac[0] += SHR32(ac[0],13);
 #else
             ac[0] *= 1.0001f;
 #endif
             /* Use lag windowing to stabilize the Levinson-Durbin recursion. */
             for (i=1;i<=LPC_ORDER;i++)
             {
                /*ac[i] *= exp(-.5*(2*M_PI*.002*i)*(2*M_PI*.002*i));*/
 #ifdef FIXED_POINT
                ac[i] -= MULT16_32_Q15(2*i*i, ac[i]);
 #else
                ac[i] -= ac[i]*(0.008f*0.008f)*i*i;
 #endif
             }
             _celt_lpc(lpc+c*LPC_ORDER, ac, LPC_ORDER);
          }
          /* We want the excitation for 2 pitch periods in order to look for a
             decaying signal, but we can't get more than MAX_PERIOD. */
          exc_length = IMIN(2*pitch_index, MAX_PERIOD);
          /* Initialize the LPC history with the samples just before the start
             of the region for which we're computing the excitation. */
          {
             opus_val16 lpc_mem[LPC_ORDER];
             for (i=0;i<LPC_ORDER;i++)
             {
                lpc_mem[i] =
                      ROUND16(buf[DECODE_BUFFER_SIZE-exc_length-1-i], SIG_SHIFT);
             }
             /* Compute the excitation for exc_length samples before the loss. */
             celt_fir(exc+MAX_PERIOD-exc_length, lpc+c*LPC_ORDER,
                   exc+MAX_PERIOD-exc_length, exc_length, LPC_ORDER, lpc_mem);
          }
          /* Check if the waveform is decaying, and if so how fast.
             We do this to avoid adding energy when concealing in a segment
             with decaying energy. */
          {
             opus_val32 E1=1, E2=1;
             int decay_length;
 #ifdef FIXED_POINT
             int shift = IMAX(0,2*celt_zlog2(celt_maxabs16(&exc[MAX_PERIOD-exc_length], exc_length))-20);
 #endif
             decay_length = exc_length>>1;
             for (i=0;i<decay_length;i++)
             {
                opus_val16 e;
                e = exc[MAX_PERIOD-decay_length+i];
                E1 += SHR32(MULT16_16(e, e), shift);
                e = exc[MAX_PERIOD-2*decay_length+i];
                E2 += SHR32(MULT16_16(e, e), shift);
             }
             E1 = MIN32(E1, E2);
             decay = celt_sqrt(frac_div32(SHR32(E1, 1), E2));
          }
          /* Move the decoder memory one frame to the left to give us room to
             add the data for the new frame. We ignore the overlap that extends
             past the end of the buffer, because we aren't going to use it. */
          OPUS_MOVE(buf, buf+N, DECODE_BUFFER_SIZE-N);
          /* Extrapolate from the end of the excitation with a period of
             "pitch_index", scaling down each period by an additional factor of
             "decay". */
          extrapolation_offset = MAX_PERIOD-pitch_index;
          /* We need to extrapolate enough samples to cover a complete MDCT
             window (including overlap/2 samples on both sides). */
          extrapolation_len = N+overlap;
          /* We also apply fading if this is not the first loss. */
          attenuation = MULT16_16_Q15(fade, decay);
          for (i=j=0;i<extrapolation_len;i++,j++)
          {
             opus_val16 tmp;
             if (j >= pitch_index) {
                j -= pitch_index;
                attenuation = MULT16_16_Q15(attenuation, decay);
             }
             buf[DECODE_BUFFER_SIZE-N+i] =
                   SHL32(EXTEND32(MULT16_16_Q15(attenuation,
                         exc[extrapolation_offset+j])), SIG_SHIFT);
             /* Compute the energy of the previously decoded signal whose
                excitation we're copying. */
             tmp = ROUND16(
                   buf[DECODE_BUFFER_SIZE-MAX_PERIOD-N+extrapolation_offset+j],
                   SIG_SHIFT);
             S1 += SHR32(MULT16_16(tmp, tmp), 8);
          }
          {
             opus_val16 lpc_mem[LPC_ORDER];
             /* Copy the last decoded samples (prior to the overlap region) to
                synthesis filter memory so we can have a continuous signal. */
             for (i=0;i<LPC_ORDER;i++)
                lpc_mem[i] = ROUND16(buf[DECODE_BUFFER_SIZE-N-1-i], SIG_SHIFT);
             /* Apply the synthesis filter to convert the excitation back into
                the signal domain. */
             celt_iir(buf+DECODE_BUFFER_SIZE-N, lpc+c*LPC_ORDER,
                   buf+DECODE_BUFFER_SIZE-N, extrapolation_len, LPC_ORDER,
                   lpc_mem);
          }
          /* Check if the synthesis energy is higher than expected, which can
             happen with the signal changes during our window. If so,
             attenuate. */
          {
             opus_val32 S2=0;
             for (i=0;i<extrapolation_len;i++)
             {
                opus_val16 tmp = ROUND16(buf[DECODE_BUFFER_SIZE-N+i], SIG_SHIFT);
                S2 += SHR32(MULT16_16(tmp, tmp), 8);
             }
             /* This checks for an "explosion" in the synthesis. */
 #ifdef FIXED_POINT
             if (!(S1 > SHR32(S2,2)))
 #else
             /* The float test is written this way to catch NaNs in the output
                of the IIR filter at the same time. */
             if (!(S1 > 0.2f*S2))
 #endif
             {
                for (i=0;i<extrapolation_len;i++)
                   buf[DECODE_BUFFER_SIZE-N+i] = 0;
             } else if (S1 < S2)
             {
                opus_val16 ratio = celt_sqrt(frac_div32(SHR32(S1,1)+1,S2+1));
                for (i=0;i<overlap;i++)
                {
                   opus_val16 tmp_g = Q15ONE
                         - MULT16_16_Q15(window[i], Q15ONE-ratio);
                   buf[DECODE_BUFFER_SIZE-N+i] =
                         MULT16_32_Q15(tmp_g, buf[DECODE_BUFFER_SIZE-N+i]);
                }
                for (i=overlap;i<extrapolation_len;i++)
                {
                   buf[DECODE_BUFFER_SIZE-N+i] =
                         MULT16_32_Q15(ratio, buf[DECODE_BUFFER_SIZE-N+i]);
                }
             }
          }
          /* Apply the pre-filter to the MDCT overlap for the next frame because
             the post-filter will be re-applied in the decoder after the MDCT
             overlap. */
          comb_filter(etmp, buf+DECODE_BUFFER_SIZE,
               st->postfilter_period, st->postfilter_period, overlap,
               -st->postfilter_gain, -st->postfilter_gain,
               st->postfilter_tapset, st->postfilter_tapset, NULL, 0);
          /* Simulate TDAC on the concealed audio so that it blends with the
             MDCT of the next frame. */
          for (i=0;i<overlap/2;i++)
          {
             buf[DECODE_BUFFER_SIZE+i] =
                MULT16_32_Q15(window[i], etmp[overlap-1-i])
                + MULT16_32_Q15(window[overlap-i-1], etmp[i]);
          }
       } while (++c<C);
    }
    deemphasis(out_syn, pcm, N, C, downsample,
          mode->preemph, st->preemph_memD, scratch);
    st->loss_count = loss_count+1;
    RESTORE_STACK;
 }
 int celt_decode_with_ec(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, opus_val16 * OPUS_RESTRICT pcm, int frame_size, ec_dec *dec)
 {
    int c, i, N;
    int spread_decision;
    opus_int32 bits;
    ec_dec _dec;
    VARDECL(celt_sig, freq);
    VARDECL(celt_norm, X);
    VARDECL(int, fine_quant);
    VARDECL(int, pulses);
    VARDECL(int, cap);
    VARDECL(int, offsets);
    VARDECL(int, fine_priority);
    VARDECL(int, tf_res);
    VARDECL(unsigned char, collapse_masks);
    celt_sig *decode_mem[2];
    celt_sig *out_syn[2];
    opus_val16 *lpc;
    opus_val16 *oldBandE, *oldLogE, *oldLogE2, *backgroundLogE;
    int shortBlocks;
    int isTransient;
    int intra_ener;
    const int CC = st->channels;
    int LM, M;
    int effEnd;
    int codedBands;
    int alloc_trim;
    int postfilter_pitch;
    opus_val16 postfilter_gain;
    int intensity=0;
    int dual_stereo=0;
    opus_int32 total_bits;
    opus_int32 balance;
    opus_int32 tell;
    int dynalloc_logp;
    int postfilter_tapset;
    int anti_collapse_rsv;
    int anti_collapse_on=0;
    int silence;
    int C = st->stream_channels;
    const OpusCustomMode *mode;
    int nbEBands;
    int overlap;
    const opus_int16 *eBands;
    ALLOC_STACK;
    mode = st->mode;
    nbEBands = mode->nbEBands;
    overlap = mode->overlap;
    eBands = mode->eBands;
    frame_size *= st->downsample;
    c=0; do {
       decode_mem[c] = st->_decode_mem + c*(DECODE_BUFFER_SIZE+overlap);
    } while (++c<CC);
    lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+overlap)*CC);
    oldBandE = lpc+CC*LPC_ORDER;
    oldLogE = oldBandE + 2*nbEBands;
    oldLogE2 = oldLogE + 2*nbEBands;
    backgroundLogE = oldLogE2  + 2*nbEBands;
 #ifdef CUSTOM_MODES
    if (st->signalling && data!=NULL)
    {
       int data0=data[0];
       /* Convert "standard mode" to Opus header */
       if (mode->Fs==48000 && mode->shortMdctSize==120)
       {
          data0 = fromOpus(data0);
          if (data0<0)
             return OPUS_INVALID_PACKET;
       }
       st->end = IMAX(1, mode->effEBands-2*(data0>>5));
       LM = (data0>>3)&0x3;
       C = 1 + ((data0>>2)&0x1);
       data++;
       len--;
       if (LM>mode->maxLM)
          return OPUS_INVALID_PACKET;
       if (frame_size < mode->shortMdctSize<<LM)
          return OPUS_BUFFER_TOO_SMALL;
       else
          frame_size = mode->shortMdctSize<<LM;
    } else {
 #else
    {
 #endif
       for (LM=0;LM<=mode->maxLM;LM++)
          if (mode->shortMdctSize<<LM==frame_size)
             break;
       if (LM>mode->maxLM)
          return OPUS_BAD_ARG;
    }
    M=1<<LM;
    if (len<0 || len>1275 || pcm==NULL)
       return OPUS_BAD_ARG;
    N = M*mode->shortMdctSize;
    effEnd = st->end;
    if (effEnd > mode->effEBands)
       effEnd = mode->effEBands;
    if (data == NULL || len<=1)
    {
       celt_decode_lost(st, pcm, N, LM);
       RESTORE_STACK;
       return frame_size/st->downsample;
    }
    if (dec == NULL)
    {
       ec_dec_init(&_dec,(unsigned char*)data,len);
       dec = &_dec;
    }
    if (C==1)
    {
       for (i=0;i<nbEBands;i++)
          oldBandE[i]=MAX16(oldBandE[i],oldBandE[nbEBands+i]);
    }
    total_bits = len*8;
    tell = ec_tell(dec);
    if (tell >= total_bits)
       silence = 1;
    else if (tell==1)
       silence = ec_dec_bit_logp(dec, 15);
    else
       silence = 0;
    if (silence)
    {
       /* Pretend we've read all the remaining bits */
       tell = len*8;
       dec->nbits_total+=tell-ec_tell(dec);
    }
    postfilter_gain = 0;
    postfilter_pitch = 0;
    postfilter_tapset = 0;
    if (st->start==0 && tell+16 <= total_bits)
    {
       if(ec_dec_bit_logp(dec, 1))
       {
          int qg, octave;
          octave = ec_dec_uint(dec, 6);
          postfilter_pitch = (16<<octave)+ec_dec_bits(dec, 4+octave)-1;
          qg = ec_dec_bits(dec, 3);
          if (ec_tell(dec)+2<=total_bits)
             postfilter_tapset = ec_dec_icdf(dec, tapset_icdf, 2);
          postfilter_gain = QCONST16(.09375f,15)*(qg+1);
       }
       tell = ec_tell(dec);
    }
    if (LM > 0 && tell+3 <= total_bits)
    {
       isTransient = ec_dec_bit_logp(dec, 3);
       tell = ec_tell(dec);
    }
    else
       isTransient = 0;
    if (isTransient)
       shortBlocks = M;
    else
       shortBlocks = 0;
    /* Decode the global flags (first symbols in the stream) */
    intra_ener = tell+3<=total_bits ? ec_dec_bit_logp(dec, 3) : 0;
    /* Get band energies */
    unquant_coarse_energy(mode, st->start, st->end, oldBandE,
          intra_ener, dec, C, LM);
    ALLOC(tf_res, nbEBands, int);
    tf_decode(st->start, st->end, isTransient, tf_res, LM, dec);
    tell = ec_tell(dec);
    spread_decision = SPREAD_NORMAL;
    if (tell+4 <= total_bits)
       spread_decision = ec_dec_icdf(dec, spread_icdf, 5);
    ALLOC(cap, nbEBands, int);
    init_caps(mode,cap,LM,C);
    ALLOC(offsets, nbEBands, int);
    dynalloc_logp = 6;
    total_bits<<=BITRES;
    tell = ec_tell_frac(dec);
    for (i=st->start;i<st->end;i++)
    {
       int width, quanta;
       int dynalloc_loop_logp;
       int boost;
       width = C*(eBands[i+1]-eBands[i])<<LM;
       /* quanta is 6 bits, but no more than 1 bit/sample
          and no less than 1/8 bit/sample */
       quanta = IMIN(width<<BITRES, IMAX(6<<BITRES, width));
       dynalloc_loop_logp = dynalloc_logp;
       boost = 0;
       while (tell+(dynalloc_loop_logp<<BITRES) < total_bits && boost < cap[i])
       {
          int flag;
          flag = ec_dec_bit_logp(dec, dynalloc_loop_logp);
          tell = ec_tell_frac(dec);
          if (!flag)
             break;
          boost += quanta;
          total_bits -= quanta;
          dynalloc_loop_logp = 1;
       }
       offsets[i] = boost;
       /* Making dynalloc more likely */
       if (boost>0)
          dynalloc_logp = IMAX(2, dynalloc_logp-1);
    }
    ALLOC(fine_quant, nbEBands, int);
    alloc_trim = tell+(6<<BITRES) <= total_bits ?
          ec_dec_icdf(dec, trim_icdf, 7) : 5;
    bits = (((opus_int32)len*8)<<BITRES) - ec_tell_frac(dec) - 1;
    anti_collapse_rsv = isTransient&&LM>=2&&bits>=((LM+2)<<BITRES) ? (1<<BITRES) : 0;
    bits -= anti_collapse_rsv;
    ALLOC(pulses, nbEBands, int);
    ALLOC(fine_priority, nbEBands, int);
    codedBands = compute_allocation(mode, st->start, st->end, offsets, cap,
          alloc_trim, &intensity, &dual_stereo, bits, &balance, pulses,
          fine_quant, fine_priority, C, LM, dec, 0, 0, 0);
    unquant_fine_energy(mode, st->start, st->end, oldBandE, fine_quant, dec, C);
    /* Decode fixed codebook */
    ALLOC(collapse_masks, C*nbEBands, unsigned char);
    ALLOC(X, C*N, celt_norm);   /**< Interleaved normalised MDCTs */
    quant_all_bands(0, mode, st->start, st->end, X, C==2 ? X+N : NULL, collapse_masks,
          NULL, pulses, shortBlocks, spread_decision, dual_stereo, intensity, tf_res,
          len*(8<<BITRES)-anti_collapse_rsv, balance, dec, LM, codedBands, &st->rng);
    if (anti_collapse_rsv > 0)
    {
       anti_collapse_on = ec_dec_bits(dec, 1);
    }
    unquant_energy_finalise(mode, st->start, st->end, oldBandE,
          fine_quant, fine_priority, len*8-ec_tell(dec), dec, C);
    if (anti_collapse_on)
       anti_collapse(mode, X, collapse_masks, LM, C, N,
             st->start, st->end, oldBandE, oldLogE, oldLogE2, pulses, st->rng);
    ALLOC(freq, IMAX(CC,C)*N, celt_sig); /**< Interleaved signal MDCTs */
    if (silence)
    {
       for (i=0;i<C*nbEBands;i++)
          oldBandE[i] = -QCONST16(28.f,DB_SHIFT);
       for (i=0;i<C*N;i++)
          freq[i] = 0;
    } else {
       /* Synthesis */
       denormalise_bands(mode, X, freq, oldBandE, st->start, effEnd, C, M);
    }
    c=0; do {
       OPUS_MOVE(decode_mem[c], decode_mem[c]+N, DECODE_BUFFER_SIZE-N+overlap/2);
    } while (++c<CC);
    c=0; do {
       int bound = M*eBands[effEnd];
       if (st->downsample!=1)
          bound = IMIN(bound, N/st->downsample);
       for (i=bound;i<N;i++)
          freq[c*N+i] = 0;
    } while (++c<C);
    c=0; do {
       out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
    } while (++c<CC);
    if (CC==2&&C==1)
    {
       for (i=0;i<N;i++)
          freq[N+i] = freq[i];
    }
    if (CC==1&&C==2)
    {
       for (i=0;i<N;i++)
          freq[i] = HALF32(ADD32(freq[i],freq[N+i]));
    }
    /* Compute inverse MDCTs */
    compute_inv_mdcts(mode, shortBlocks, freq, out_syn, CC, LM);
    c=0; do {
       st->postfilter_period=IMAX(st->postfilter_period, COMBFILTER_MINPERIOD);
       st->postfilter_period_old=IMAX(st->postfilter_period_old, COMBFILTER_MINPERIOD);
       comb_filter(out_syn[c], out_syn[c], st->postfilter_period_old, st->postfilter_period, mode->shortMdctSize,
             st->postfilter_gain_old, st->postfilter_gain, st->postfilter_tapset_old, st->postfilter_tapset,
             mode->window, overlap);
       if (LM!=0)
          comb_filter(out_syn[c]+mode->shortMdctSize, out_syn[c]+mode->shortMdctSize, st->postfilter_period, postfilter_pitch, N-mode->shortMdctSize,
                st->postfilter_gain, postfilter_gain, st->postfilter_tapset, postfilter_tapset,
                mode->window, overlap);
    } while (++c<CC);
    st->postfilter_period_old = st->postfilter_period;
    st->postfilter_gain_old = st->postfilter_gain;
    st->postfilter_tapset_old = st->postfilter_tapset;
    st->postfilter_period = postfilter_pitch;
    st->postfilter_gain = postfilter_gain;
    st->postfilter_tapset = postfilter_tapset;
    if (LM!=0)
    {
       st->postfilter_period_old = st->postfilter_period;
       st->postfilter_gain_old = st->postfilter_gain;
       st->postfilter_tapset_old = st->postfilter_tapset;
    }
    if (C==1) {
       for (i=0;i<nbEBands;i++)
          oldBandE[nbEBands+i]=oldBandE[i];
    }
    /* In case start or end were to change */
    if (!isTransient)
    {
       for (i=0;i<2*nbEBands;i++)
          oldLogE2[i] = oldLogE[i];
       for (i=0;i<2*nbEBands;i++)
          oldLogE[i] = oldBandE[i];
       for (i=0;i<2*nbEBands;i++)
          backgroundLogE[i] = MIN16(backgroundLogE[i] + M*QCONST16(0.001f,DB_SHIFT), oldBandE[i]);
    } else {
       for (i=0;i<2*nbEBands;i++)
          oldLogE[i] = MIN16(oldLogE[i], oldBandE[i]);
    }
    c=0; do
    {
       for (i=0;i<st->start;i++)
       {
          oldBandE[c*nbEBands+i]=0;
          oldLogE[c*nbEBands+i]=oldLogE2[c*nbEBands+i]=-QCONST16(28.f,DB_SHIFT);
       }
       for (i=st->end;i<nbEBands;i++)
       {
          oldBandE[c*nbEBands+i]=0;
          oldLogE[c*nbEBands+i]=oldLogE2[c*nbEBands+i]=-QCONST16(28.f,DB_SHIFT);
       }
    } while (++c<2);
    st->rng = dec->rng;
    /* We reuse freq[] as scratch space for the de-emphasis */
    deemphasis(out_syn, pcm, N, CC, st->downsample, mode->preemph, st->preemph_memD, freq);
    st->loss_count = 0;
    RESTORE_STACK;
    if (ec_tell(dec) > 8*len)
       return OPUS_INTERNAL_ERROR;
    if(ec_get_error(dec))
       st->error = 1;
    return frame_size/st->downsample;
 }
 #ifdef CUSTOM_MODES
 #ifdef FIXED_POINT
 int opus_custom_decode(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, opus_int16 * OPUS_RESTRICT pcm, int frame_size)
 {
    return celt_decode_with_ec(st, data, len, pcm, frame_size, NULL);
 }
 #ifndef DISABLE_FLOAT_API
 int opus_custom_decode_float(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, float * OPUS_RESTRICT pcm, int frame_size)
 {
    int j, ret, C, N;
    VARDECL(opus_int16, out);
    ALLOC_STACK;
    if (pcm==NULL)
       return OPUS_BAD_ARG;
    C = st->channels;
    N = frame_size;
    ALLOC(out, C*N, opus_int16);
    ret=celt_decode_with_ec(st, data, len, out, frame_size, NULL);
    if (ret>0)
       for (j=0;j<C*ret;j++)
          pcm[j]=out[j]*(1.f/32768.f);
    RESTORE_STACK;
    return ret;
 }
 #endif /* DISABLE_FLOAT_API */
 #else
 int opus_custom_decode_float(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, float * OPUS_RESTRICT pcm, int frame_size)
 {
    return celt_decode_with_ec(st, data, len, pcm, frame_size, NULL);
 }
 int opus_custom_decode(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, opus_int16 * OPUS_RESTRICT pcm, int frame_size)
 {
    int j, ret, C, N;
    VARDECL(celt_sig, out);
    ALLOC_STACK;
    if (pcm==NULL)
       return OPUS_BAD_ARG;
    C = st->channels;
    N = frame_size;
    ALLOC(out, C*N, celt_sig);
    ret=celt_decode_with_ec(st, data, len, out, frame_size, NULL);
    if (ret>0)
       for (j=0;j<C*ret;j++)
          pcm[j] = FLOAT2INT16 (out[j]);
    RESTORE_STACK;
    return ret;
 }
 #endif
 #endif /* CUSTOM_MODES */
 int opus_custom_decoder_ctl(CELTDecoder * OPUS_RESTRICT st, int request, ...)
 {
    va_list ap;
    va_start(ap, request);
    switch (request)
    {
       case CELT_SET_START_BAND_REQUEST:
       {
          opus_int32 value = va_arg(ap, opus_int32);
          if (value<0 || value>=st->mode->nbEBands)
             goto bad_arg;
          st->start = value;
       }
       break;
       case CELT_SET_END_BAND_REQUEST:
       {
          opus_int32 value = va_arg(ap, opus_int32);
          if (value<1 || value>st->mode->nbEBands)
             goto bad_arg;
          st->end = value;
       }
       break;
       case CELT_SET_CHANNELS_REQUEST:
       {
          opus_int32 value = va_arg(ap, opus_int32);
          if (value<1 || value>2)
             goto bad_arg;
          st->stream_channels = value;
       }
       break;
       case CELT_GET_AND_CLEAR_ERROR_REQUEST:
       {
          opus_int32 *value = va_arg(ap, opus_int32*);
          if (value==NULL)
             goto bad_arg;
          *value=st->error;
          st->error = 0;
       }
       break;
       case OPUS_GET_LOOKAHEAD_REQUEST:
       {
          opus_int32 *value = va_arg(ap, opus_int32*);
          if (value==NULL)
             goto bad_arg;
          *value = st->overlap/st->downsample;
       }
       break;
       case OPUS_RESET_STATE:
       {
          int i;
          opus_val16 *lpc, *oldBandE, *oldLogE, *oldLogE2;
          lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+st->overlap)*st->channels);
          oldBandE = lpc+st->channels*LPC_ORDER;
          oldLogE = oldBandE + 2*st->mode->nbEBands;
          oldLogE2 = oldLogE + 2*st->mode->nbEBands;
          OPUS_CLEAR((char*)&st->DECODER_RESET_START,
                opus_custom_decoder_get_size(st->mode, st->channels)-
                ((char*)&st->DECODER_RESET_START - (char*)st));
          for (i=0;i<2*st->mode->nbEBands;i++)
             oldLogE[i]=oldLogE2[i]=-QCONST16(28.f,DB_SHIFT);
       }
       break;
       case OPUS_GET_PITCH_REQUEST:
       {
          opus_int32 *value = va_arg(ap, opus_int32*);
          if (value==NULL)
             goto bad_arg;
          *value = st->postfilter_period;
       }
       break;
       case CELT_GET_MODE_REQUEST:
       {
          const CELTMode ** value = va_arg(ap, const CELTMode**);
          if (value==0)
             goto bad_arg;
          *value=st->mode;
       }
       break;
       case CELT_SET_SIGNALLING_REQUEST:
       {
          opus_int32 value = va_arg(ap, opus_int32);
          st->signalling = value;
       }
       break;
       case OPUS_GET_FINAL_RANGE_REQUEST:
       {
          opus_uint32 * value = va_arg(ap, opus_uint32 *);
          if (value==0)
             goto bad_arg;
          *value=st->rng;
       }
       break;
       default:
          goto bad_request;
    }
    va_end(ap);
    return OPUS_OK;
 bad_arg:
    va_end(ap);
    return OPUS_BAD_ARG;
 bad_request:
       va_end(ap);
   return OPUS_UNIMPLEMENTED;
 }

The Tor Browser / annotate

media/libopus/celt/celt_decoder.c@6474c204b198 (annotated)

media/libopus/celt/celt_decoder.c