cannam@154: /* Copyright (c) 2007-2008 CSIRO
cannam@154:    Copyright (c) 2007-2010 Xiph.Org Foundation
cannam@154:    Copyright (c) 2008 Gregory Maxwell
cannam@154:    Written by Jean-Marc Valin and Gregory Maxwell */
cannam@154: /*
cannam@154:    Redistribution and use in source and binary forms, with or without
cannam@154:    modification, are permitted provided that the following conditions
cannam@154:    are met:
cannam@154: 
cannam@154:    - Redistributions of source code must retain the above copyright
cannam@154:    notice, this list of conditions and the following disclaimer.
cannam@154: 
cannam@154:    - Redistributions in binary form must reproduce the above copyright
cannam@154:    notice, this list of conditions and the following disclaimer in the
cannam@154:    documentation and/or other materials provided with the distribution.
cannam@154: 
cannam@154:    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
cannam@154:    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
cannam@154:    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
cannam@154:    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
cannam@154:    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
cannam@154:    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
cannam@154:    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
cannam@154:    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
cannam@154:    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
cannam@154:    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
cannam@154:    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
cannam@154: */
cannam@154: 
cannam@154: #ifdef HAVE_CONFIG_H
cannam@154: #include "config.h"
cannam@154: #endif
cannam@154: 
cannam@154: #define CELT_DECODER_C
cannam@154: 
cannam@154: #include "cpu_support.h"
cannam@154: #include "os_support.h"
cannam@154: #include "mdct.h"
cannam@154: #include <math.h>
cannam@154: #include "celt.h"
cannam@154: #include "pitch.h"
cannam@154: #include "bands.h"
cannam@154: #include "modes.h"
cannam@154: #include "entcode.h"
cannam@154: #include "quant_bands.h"
cannam@154: #include "rate.h"
cannam@154: #include "stack_alloc.h"
cannam@154: #include "mathops.h"
cannam@154: #include "float_cast.h"
cannam@154: #include <stdarg.h>
cannam@154: #include "celt_lpc.h"
cannam@154: #include "vq.h"
cannam@154: 
cannam@154: /* The maximum pitch lag to allow in the pitch-based PLC. It's possible to save
cannam@154:    CPU time in the PLC pitch search by making this smaller than MAX_PERIOD. The
cannam@154:    current value corresponds to a pitch of 66.67 Hz. */
cannam@154: #define PLC_PITCH_LAG_MAX (720)
cannam@154: /* The minimum pitch lag to allow in the pitch-based PLC. This corresponds to a
cannam@154:    pitch of 480 Hz. */
cannam@154: #define PLC_PITCH_LAG_MIN (100)
cannam@154: 
cannam@154: #if defined(SMALL_FOOTPRINT) && defined(FIXED_POINT)
cannam@154: #define NORM_ALIASING_HACK
cannam@154: #endif
cannam@154: /**********************************************************************/
cannam@154: /*                                                                    */
cannam@154: /*                             DECODER                                */
cannam@154: /*                                                                    */
cannam@154: /**********************************************************************/
cannam@154: #define DECODE_BUFFER_SIZE 2048
cannam@154: 
cannam@154: /** Decoder state
cannam@154:  @brief Decoder state
cannam@154:  */
cannam@154: struct OpusCustomDecoder {
cannam@154:    const OpusCustomMode *mode;
cannam@154:    int overlap;
cannam@154:    int channels;
cannam@154:    int stream_channels;
cannam@154: 
cannam@154:    int downsample;
cannam@154:    int start, end;
cannam@154:    int signalling;
cannam@154:    int disable_inv;
cannam@154:    int arch;
cannam@154: 
cannam@154:    /* Everything beyond this point gets cleared on a reset */
cannam@154: #define DECODER_RESET_START rng
cannam@154: 
cannam@154:    opus_uint32 rng;
cannam@154:    int error;
cannam@154:    int last_pitch_index;
cannam@154:    int loss_count;
cannam@154:    int skip_plc;
cannam@154:    int postfilter_period;
cannam@154:    int postfilter_period_old;
cannam@154:    opus_val16 postfilter_gain;
cannam@154:    opus_val16 postfilter_gain_old;
cannam@154:    int postfilter_tapset;
cannam@154:    int postfilter_tapset_old;
cannam@154: 
cannam@154:    celt_sig preemph_memD[2];
cannam@154: 
cannam@154:    celt_sig _decode_mem[1]; /* Size = channels*(DECODE_BUFFER_SIZE+mode->overlap) */
cannam@154:    /* opus_val16 lpc[],  Size = channels*LPC_ORDER */
cannam@154:    /* opus_val16 oldEBands[], Size = 2*mode->nbEBands */
cannam@154:    /* opus_val16 oldLogE[], Size = 2*mode->nbEBands */
cannam@154:    /* opus_val16 oldLogE2[], Size = 2*mode->nbEBands */
cannam@154:    /* opus_val16 backgroundLogE[], Size = 2*mode->nbEBands */
cannam@154: };
cannam@154: 
cannam@154: #if defined(ENABLE_HARDENING) || defined(ENABLE_ASSERTIONS)
cannam@154: /* Make basic checks on the CELT state to ensure we don't end
cannam@154:    up writing all over memory. */
cannam@154: void validate_celt_decoder(CELTDecoder *st)
cannam@154: {
cannam@154: #ifndef CUSTOM_MODES
cannam@154:    celt_assert(st->mode == opus_custom_mode_create(48000, 960, NULL));
cannam@154:    celt_assert(st->overlap == 120);
cannam@154: #endif
cannam@154:    celt_assert(st->channels == 1 || st->channels == 2);
cannam@154:    celt_assert(st->stream_channels == 1 || st->stream_channels == 2);
cannam@154:    celt_assert(st->downsample > 0);
cannam@154:    celt_assert(st->start == 0 || st->start == 17);
cannam@154:    celt_assert(st->start < st->end);
cannam@154:    celt_assert(st->end <= 21);
cannam@154: #ifdef OPUS_ARCHMASK
cannam@154:    celt_assert(st->arch >= 0);
cannam@154:    celt_assert(st->arch <= OPUS_ARCHMASK);
cannam@154: #endif
cannam@154:    celt_assert(st->last_pitch_index <= PLC_PITCH_LAG_MAX);
cannam@154:    celt_assert(st->last_pitch_index >= PLC_PITCH_LAG_MIN || st->last_pitch_index == 0);
cannam@154:    celt_assert(st->postfilter_period < MAX_PERIOD);
cannam@154:    celt_assert(st->postfilter_period >= COMBFILTER_MINPERIOD || st->postfilter_period == 0);
cannam@154:    celt_assert(st->postfilter_period_old < MAX_PERIOD);
cannam@154:    celt_assert(st->postfilter_period_old >= COMBFILTER_MINPERIOD || st->postfilter_period_old == 0);
cannam@154:    celt_assert(st->postfilter_tapset <= 2);
cannam@154:    celt_assert(st->postfilter_tapset >= 0);
cannam@154:    celt_assert(st->postfilter_tapset_old <= 2);
cannam@154:    celt_assert(st->postfilter_tapset_old >= 0);
cannam@154: }
cannam@154: #endif
cannam@154: 
cannam@154: int celt_decoder_get_size(int channels)
cannam@154: {
cannam@154:    const CELTMode *mode = opus_custom_mode_create(48000, 960, NULL);
cannam@154:    return opus_custom_decoder_get_size(mode, channels);
cannam@154: }
cannam@154: 
cannam@154: OPUS_CUSTOM_NOSTATIC int opus_custom_decoder_get_size(const CELTMode *mode, int channels)
cannam@154: {
cannam@154:    int size = sizeof(struct CELTDecoder)
cannam@154:             + (channels*(DECODE_BUFFER_SIZE+mode->overlap)-1)*sizeof(celt_sig)
cannam@154:             + channels*LPC_ORDER*sizeof(opus_val16)
cannam@154:             + 4*2*mode->nbEBands*sizeof(opus_val16);
cannam@154:    return size;
cannam@154: }
cannam@154: 
cannam@154: #ifdef CUSTOM_MODES
cannam@154: CELTDecoder *opus_custom_decoder_create(const CELTMode *mode, int channels, int *error)
cannam@154: {
cannam@154:    int ret;
cannam@154:    CELTDecoder *st = (CELTDecoder *)opus_alloc(opus_custom_decoder_get_size(mode, channels));
cannam@154:    ret = opus_custom_decoder_init(st, mode, channels);
cannam@154:    if (ret != OPUS_OK)
cannam@154:    {
cannam@154:       opus_custom_decoder_destroy(st);
cannam@154:       st = NULL;
cannam@154:    }
cannam@154:    if (error)
cannam@154:       *error = ret;
cannam@154:    return st;
cannam@154: }
cannam@154: #endif /* CUSTOM_MODES */
cannam@154: 
cannam@154: int celt_decoder_init(CELTDecoder *st, opus_int32 sampling_rate, int channels)
cannam@154: {
cannam@154:    int ret;
cannam@154:    ret = opus_custom_decoder_init(st, opus_custom_mode_create(48000, 960, NULL), channels);
cannam@154:    if (ret != OPUS_OK)
cannam@154:       return ret;
cannam@154:    st->downsample = resampling_factor(sampling_rate);
cannam@154:    if (st->downsample==0)
cannam@154:       return OPUS_BAD_ARG;
cannam@154:    else
cannam@154:       return OPUS_OK;
cannam@154: }
cannam@154: 
cannam@154: OPUS_CUSTOM_NOSTATIC int opus_custom_decoder_init(CELTDecoder *st, const CELTMode *mode, int channels)
cannam@154: {
cannam@154:    if (channels < 0 || channels > 2)
cannam@154:       return OPUS_BAD_ARG;
cannam@154: 
cannam@154:    if (st==NULL)
cannam@154:       return OPUS_ALLOC_FAIL;
cannam@154: 
cannam@154:    OPUS_CLEAR((char*)st, opus_custom_decoder_get_size(mode, channels));
cannam@154: 
cannam@154:    st->mode = mode;
cannam@154:    st->overlap = mode->overlap;
cannam@154:    st->stream_channels = st->channels = channels;
cannam@154: 
cannam@154:    st->downsample = 1;
cannam@154:    st->start = 0;
cannam@154:    st->end = st->mode->effEBands;
cannam@154:    st->signalling = 1;
cannam@154: #ifndef DISABLE_UPDATE_DRAFT
cannam@154:    st->disable_inv = channels == 1;
cannam@154: #else
cannam@154:    st->disable_inv = 0;
cannam@154: #endif
cannam@154:    st->arch = opus_select_arch();
cannam@154: 
cannam@154:    opus_custom_decoder_ctl(st, OPUS_RESET_STATE);
cannam@154: 
cannam@154:    return OPUS_OK;
cannam@154: }
cannam@154: 
cannam@154: #ifdef CUSTOM_MODES
cannam@154: void opus_custom_decoder_destroy(CELTDecoder *st)
cannam@154: {
cannam@154:    opus_free(st);
cannam@154: }
cannam@154: #endif /* CUSTOM_MODES */
cannam@154: 
cannam@154: #ifndef CUSTOM_MODES
cannam@154: /* Special case for stereo with no downsampling and no accumulation. This is
cannam@154:    quite common and we can make it faster by processing both channels in the
cannam@154:    same loop, reducing overhead due to the dependency loop in the IIR filter. */
cannam@154: static void deemphasis_stereo_simple(celt_sig *in[], opus_val16 *pcm, int N, const opus_val16 coef0,
cannam@154:       celt_sig *mem)
cannam@154: {
cannam@154:    celt_sig * OPUS_RESTRICT x0;
cannam@154:    celt_sig * OPUS_RESTRICT x1;
cannam@154:    celt_sig m0, m1;
cannam@154:    int j;
cannam@154:    x0=in[0];
cannam@154:    x1=in[1];
cannam@154:    m0 = mem[0];
cannam@154:    m1 = mem[1];
cannam@154:    for (j=0;j<N;j++)
cannam@154:    {
cannam@154:       celt_sig tmp0, tmp1;
cannam@154:       /* Add VERY_SMALL to x[] first to reduce dependency chain. */
cannam@154:       tmp0 = x0[j] + VERY_SMALL + m0;
cannam@154:       tmp1 = x1[j] + VERY_SMALL + m1;
cannam@154:       m0 = MULT16_32_Q15(coef0, tmp0);
cannam@154:       m1 = MULT16_32_Q15(coef0, tmp1);
cannam@154:       pcm[2*j  ] = SCALEOUT(SIG2WORD16(tmp0));
cannam@154:       pcm[2*j+1] = SCALEOUT(SIG2WORD16(tmp1));
cannam@154:    }
cannam@154:    mem[0] = m0;
cannam@154:    mem[1] = m1;
cannam@154: }
cannam@154: #endif
cannam@154: 
cannam@154: #ifndef RESYNTH
cannam@154: static
cannam@154: #endif
cannam@154: void deemphasis(celt_sig *in[], opus_val16 *pcm, int N, int C, int downsample, const opus_val16 *coef,
cannam@154:       celt_sig *mem, int accum)
cannam@154: {
cannam@154:    int c;
cannam@154:    int Nd;
cannam@154:    int apply_downsampling=0;
cannam@154:    opus_val16 coef0;
cannam@154:    VARDECL(celt_sig, scratch);
cannam@154:    SAVE_STACK;
cannam@154: #ifndef CUSTOM_MODES
cannam@154:    /* Short version for common case. */
cannam@154:    if (downsample == 1 && C == 2 && !accum)
cannam@154:    {
cannam@154:       deemphasis_stereo_simple(in, pcm, N, coef[0], mem);
cannam@154:       return;
cannam@154:    }
cannam@154: #endif
cannam@154: #ifndef FIXED_POINT
cannam@154:    (void)accum;
cannam@154:    celt_assert(accum==0);
cannam@154: #endif
cannam@154:    ALLOC(scratch, N, celt_sig);
cannam@154:    coef0 = coef[0];
cannam@154:    Nd = N/downsample;
cannam@154:    c=0; do {
cannam@154:       int j;
cannam@154:       celt_sig * OPUS_RESTRICT x;
cannam@154:       opus_val16  * OPUS_RESTRICT y;
cannam@154:       celt_sig m = mem[c];
cannam@154:       x =in[c];
cannam@154:       y = pcm+c;
cannam@154: #ifdef CUSTOM_MODES
cannam@154:       if (coef[1] != 0)
cannam@154:       {
cannam@154:          opus_val16 coef1 = coef[1];
cannam@154:          opus_val16 coef3 = coef[3];
cannam@154:          for (j=0;j<N;j++)
cannam@154:          {
cannam@154:             celt_sig tmp = x[j] + m + VERY_SMALL;
cannam@154:             m = MULT16_32_Q15(coef0, tmp)
cannam@154:                           - MULT16_32_Q15(coef1, x[j]);
cannam@154:             tmp = SHL32(MULT16_32_Q15(coef3, tmp), 2);
cannam@154:             scratch[j] = tmp;
cannam@154:          }
cannam@154:          apply_downsampling=1;
cannam@154:       } else
cannam@154: #endif
cannam@154:       if (downsample>1)
cannam@154:       {
cannam@154:          /* Shortcut for the standard (non-custom modes) case */
cannam@154:          for (j=0;j<N;j++)
cannam@154:          {
cannam@154:             celt_sig tmp = x[j] + VERY_SMALL + m;
cannam@154:             m = MULT16_32_Q15(coef0, tmp);
cannam@154:             scratch[j] = tmp;
cannam@154:          }
cannam@154:          apply_downsampling=1;
cannam@154:       } else {
cannam@154:          /* Shortcut for the standard (non-custom modes) case */
cannam@154: #ifdef FIXED_POINT
cannam@154:          if (accum)
cannam@154:          {
cannam@154:             for (j=0;j<N;j++)
cannam@154:             {
cannam@154:                celt_sig tmp = x[j] + m + VERY_SMALL;
cannam@154:                m = MULT16_32_Q15(coef0, tmp);
cannam@154:                y[j*C] = SAT16(ADD32(y[j*C], SCALEOUT(SIG2WORD16(tmp))));
cannam@154:             }
cannam@154:          } else
cannam@154: #endif
cannam@154:          {
cannam@154:             for (j=0;j<N;j++)
cannam@154:             {
cannam@154:                celt_sig tmp = x[j] + VERY_SMALL + m;
cannam@154:                m = MULT16_32_Q15(coef0, tmp);
cannam@154:                y[j*C] = SCALEOUT(SIG2WORD16(tmp));
cannam@154:             }
cannam@154:          }
cannam@154:       }
cannam@154:       mem[c] = m;
cannam@154: 
cannam@154:       if (apply_downsampling)
cannam@154:       {
cannam@154:          /* Perform down-sampling */
cannam@154: #ifdef FIXED_POINT
cannam@154:          if (accum)
cannam@154:          {
cannam@154:             for (j=0;j<Nd;j++)
cannam@154:                y[j*C] = SAT16(ADD32(y[j*C], SCALEOUT(SIG2WORD16(scratch[j*downsample]))));
cannam@154:          } else
cannam@154: #endif
cannam@154:          {
cannam@154:             for (j=0;j<Nd;j++)
cannam@154:                y[j*C] = SCALEOUT(SIG2WORD16(scratch[j*downsample]));
cannam@154:          }
cannam@154:       }
cannam@154:    } while (++c<C);
cannam@154:    RESTORE_STACK;
cannam@154: }
cannam@154: 
cannam@154: #ifndef RESYNTH
cannam@154: static
cannam@154: #endif
cannam@154: void celt_synthesis(const CELTMode *mode, celt_norm *X, celt_sig * out_syn[],
cannam@154:                     opus_val16 *oldBandE, int start, int effEnd, int C, int CC,
cannam@154:                     int isTransient, int LM, int downsample,
cannam@154:                     int silence, int arch)
cannam@154: {
cannam@154:    int c, i;
cannam@154:    int M;
cannam@154:    int b;
cannam@154:    int B;
cannam@154:    int N, NB;
cannam@154:    int shift;
cannam@154:    int nbEBands;
cannam@154:    int overlap;
cannam@154:    VARDECL(celt_sig, freq);
cannam@154:    SAVE_STACK;
cannam@154: 
cannam@154:    overlap = mode->overlap;
cannam@154:    nbEBands = mode->nbEBands;
cannam@154:    N = mode->shortMdctSize<<LM;
cannam@154:    ALLOC(freq, N, celt_sig); /**< Interleaved signal MDCTs */
cannam@154:    M = 1<<LM;
cannam@154: 
cannam@154:    if (isTransient)
cannam@154:    {
cannam@154:       B = M;
cannam@154:       NB = mode->shortMdctSize;
cannam@154:       shift = mode->maxLM;
cannam@154:    } else {
cannam@154:       B = 1;
cannam@154:       NB = mode->shortMdctSize<<LM;
cannam@154:       shift = mode->maxLM-LM;
cannam@154:    }
cannam@154: 
cannam@154:    if (CC==2&&C==1)
cannam@154:    {
cannam@154:       /* Copying a mono streams to two channels */
cannam@154:       celt_sig *freq2;
cannam@154:       denormalise_bands(mode, X, freq, oldBandE, start, effEnd, M,
cannam@154:             downsample, silence);
cannam@154:       /* Store a temporary copy in the output buffer because the IMDCT destroys its input. */
cannam@154:       freq2 = out_syn[1]+overlap/2;
cannam@154:       OPUS_COPY(freq2, freq, N);
cannam@154:       for (b=0;b<B;b++)
cannam@154:          clt_mdct_backward(&mode->mdct, &freq2[b], out_syn[0]+NB*b, mode->window, overlap, shift, B, arch);
cannam@154:       for (b=0;b<B;b++)
cannam@154:          clt_mdct_backward(&mode->mdct, &freq[b], out_syn[1]+NB*b, mode->window, overlap, shift, B, arch);
cannam@154:    } else if (CC==1&&C==2)
cannam@154:    {
cannam@154:       /* Downmixing a stereo stream to mono */
cannam@154:       celt_sig *freq2;
cannam@154:       freq2 = out_syn[0]+overlap/2;
cannam@154:       denormalise_bands(mode, X, freq, oldBandE, start, effEnd, M,
cannam@154:             downsample, silence);
cannam@154:       /* Use the output buffer as temp array before downmixing. */
cannam@154:       denormalise_bands(mode, X+N, freq2, oldBandE+nbEBands, start, effEnd, M,
cannam@154:             downsample, silence);
cannam@154:       for (i=0;i<N;i++)
cannam@154:          freq[i] = ADD32(HALF32(freq[i]), HALF32(freq2[i]));
cannam@154:       for (b=0;b<B;b++)
cannam@154:          clt_mdct_backward(&mode->mdct, &freq[b], out_syn[0]+NB*b, mode->window, overlap, shift, B, arch);
cannam@154:    } else {
cannam@154:       /* Normal case (mono or stereo) */
cannam@154:       c=0; do {
cannam@154:          denormalise_bands(mode, X+c*N, freq, oldBandE+c*nbEBands, start, effEnd, M,
cannam@154:                downsample, silence);
cannam@154:          for (b=0;b<B;b++)
cannam@154:             clt_mdct_backward(&mode->mdct, &freq[b], out_syn[c]+NB*b, mode->window, overlap, shift, B, arch);
cannam@154:       } while (++c<CC);
cannam@154:    }
cannam@154:    /* Saturate IMDCT output so that we can't overflow in the pitch postfilter
cannam@154:       or in the */
cannam@154:    c=0; do {
cannam@154:       for (i=0;i<N;i++)
cannam@154:          out_syn[c][i] = SATURATE(out_syn[c][i], SIG_SAT);
cannam@154:    } while (++c<CC);
cannam@154:    RESTORE_STACK;
cannam@154: }
cannam@154: 
cannam@154: static void tf_decode(int start, int end, int isTransient, int *tf_res, int LM, ec_dec *dec)
cannam@154: {
cannam@154:    int i, curr, tf_select;
cannam@154:    int tf_select_rsv;
cannam@154:    int tf_changed;
cannam@154:    int logp;
cannam@154:    opus_uint32 budget;
cannam@154:    opus_uint32 tell;
cannam@154: 
cannam@154:    budget = dec->storage*8;
cannam@154:    tell = ec_tell(dec);
cannam@154:    logp = isTransient ? 2 : 4;
cannam@154:    tf_select_rsv = LM>0 && tell+logp+1<=budget;
cannam@154:    budget -= tf_select_rsv;
cannam@154:    tf_changed = curr = 0;
cannam@154:    for (i=start;i<end;i++)
cannam@154:    {
cannam@154:       if (tell+logp<=budget)
cannam@154:       {
cannam@154:          curr ^= ec_dec_bit_logp(dec, logp);
cannam@154:          tell = ec_tell(dec);
cannam@154:          tf_changed |= curr;
cannam@154:       }
cannam@154:       tf_res[i] = curr;
cannam@154:       logp = isTransient ? 4 : 5;
cannam@154:    }
cannam@154:    tf_select = 0;
cannam@154:    if (tf_select_rsv &&
cannam@154:      tf_select_table[LM][4*isTransient+0+tf_changed] !=
cannam@154:      tf_select_table[LM][4*isTransient+2+tf_changed])
cannam@154:    {
cannam@154:       tf_select = ec_dec_bit_logp(dec, 1);
cannam@154:    }
cannam@154:    for (i=start;i<end;i++)
cannam@154:    {
cannam@154:       tf_res[i] = tf_select_table[LM][4*isTransient+2*tf_select+tf_res[i]];
cannam@154:    }
cannam@154: }
cannam@154: 
cannam@154: static int celt_plc_pitch_search(celt_sig *decode_mem[2], int C, int arch)
cannam@154: {
cannam@154:    int pitch_index;
cannam@154:    VARDECL( opus_val16, lp_pitch_buf );
cannam@154:    SAVE_STACK;
cannam@154:    ALLOC( lp_pitch_buf, DECODE_BUFFER_SIZE>>1, opus_val16 );
cannam@154:    pitch_downsample(decode_mem, lp_pitch_buf,
cannam@154:          DECODE_BUFFER_SIZE, C, arch);
cannam@154:    pitch_search(lp_pitch_buf+(PLC_PITCH_LAG_MAX>>1), lp_pitch_buf,
cannam@154:          DECODE_BUFFER_SIZE-PLC_PITCH_LAG_MAX,
cannam@154:          PLC_PITCH_LAG_MAX-PLC_PITCH_LAG_MIN, &pitch_index, arch);
cannam@154:    pitch_index = PLC_PITCH_LAG_MAX-pitch_index;
cannam@154:    RESTORE_STACK;
cannam@154:    return pitch_index;
cannam@154: }
cannam@154: 
cannam@154: static void celt_decode_lost(CELTDecoder * OPUS_RESTRICT st, int N, int LM)
cannam@154: {
cannam@154:    int c;
cannam@154:    int i;
cannam@154:    const int C = st->channels;
cannam@154:    celt_sig *decode_mem[2];
cannam@154:    celt_sig *out_syn[2];
cannam@154:    opus_val16 *lpc;
cannam@154:    opus_val16 *oldBandE, *oldLogE, *oldLogE2, *backgroundLogE;
cannam@154:    const OpusCustomMode *mode;
cannam@154:    int nbEBands;
cannam@154:    int overlap;
cannam@154:    int start;
cannam@154:    int loss_count;
cannam@154:    int noise_based;
cannam@154:    const opus_int16 *eBands;
cannam@154:    SAVE_STACK;
cannam@154: 
cannam@154:    mode = st->mode;
cannam@154:    nbEBands = mode->nbEBands;
cannam@154:    overlap = mode->overlap;
cannam@154:    eBands = mode->eBands;
cannam@154: 
cannam@154:    c=0; do {
cannam@154:       decode_mem[c] = st->_decode_mem + c*(DECODE_BUFFER_SIZE+overlap);
cannam@154:       out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
cannam@154:    } while (++c<C);
cannam@154:    lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+overlap)*C);
cannam@154:    oldBandE = lpc+C*LPC_ORDER;
cannam@154:    oldLogE = oldBandE + 2*nbEBands;
cannam@154:    oldLogE2 = oldLogE + 2*nbEBands;
cannam@154:    backgroundLogE = oldLogE2  + 2*nbEBands;
cannam@154: 
cannam@154:    loss_count = st->loss_count;
cannam@154:    start = st->start;
cannam@154:    noise_based = loss_count >= 5 || start != 0 || st->skip_plc;
cannam@154:    if (noise_based)
cannam@154:    {
cannam@154:       /* Noise-based PLC/CNG */
cannam@154: #ifdef NORM_ALIASING_HACK
cannam@154:       celt_norm *X;
cannam@154: #else
cannam@154:       VARDECL(celt_norm, X);
cannam@154: #endif
cannam@154:       opus_uint32 seed;
cannam@154:       int end;
cannam@154:       int effEnd;
cannam@154:       opus_val16 decay;
cannam@154:       end = st->end;
cannam@154:       effEnd = IMAX(start, IMIN(end, mode->effEBands));
cannam@154: 
cannam@154: #ifdef NORM_ALIASING_HACK
cannam@154:       /* This is an ugly hack that breaks aliasing rules and would be easily broken,
cannam@154:          but it saves almost 4kB of stack. */
cannam@154:       X = (celt_norm*)(out_syn[C-1]+overlap/2);
cannam@154: #else
cannam@154:       ALLOC(X, C*N, celt_norm);   /**< Interleaved normalised MDCTs */
cannam@154: #endif
cannam@154: 
cannam@154:       /* Energy decay */
cannam@154:       decay = loss_count==0 ? QCONST16(1.5f, DB_SHIFT) : QCONST16(.5f, DB_SHIFT);
cannam@154:       c=0; do
cannam@154:       {
cannam@154:          for (i=start;i<end;i++)
cannam@154:             oldBandE[c*nbEBands+i] = MAX16(backgroundLogE[c*nbEBands+i], oldBandE[c*nbEBands+i] - decay);
cannam@154:       } while (++c<C);
cannam@154:       seed = st->rng;
cannam@154:       for (c=0;c<C;c++)
cannam@154:       {
cannam@154:          for (i=start;i<effEnd;i++)
cannam@154:          {
cannam@154:             int j;
cannam@154:             int boffs;
cannam@154:             int blen;
cannam@154:             boffs = N*c+(eBands[i]<<LM);
cannam@154:             blen = (eBands[i+1]-eBands[i])<<LM;
cannam@154:             for (j=0;j<blen;j++)
cannam@154:             {
cannam@154:                seed = celt_lcg_rand(seed);
cannam@154:                X[boffs+j] = (celt_norm)((opus_int32)seed>>20);
cannam@154:             }
cannam@154:             renormalise_vector(X+boffs, blen, Q15ONE, st->arch);
cannam@154:          }
cannam@154:       }
cannam@154:       st->rng = seed;
cannam@154: 
cannam@154:       c=0; do {
cannam@154:          OPUS_MOVE(decode_mem[c], decode_mem[c]+N,
cannam@154:                DECODE_BUFFER_SIZE-N+(overlap>>1));
cannam@154:       } while (++c<C);
cannam@154: 
cannam@154:       celt_synthesis(mode, X, out_syn, oldBandE, start, effEnd, C, C, 0, LM, st->downsample, 0, st->arch);
cannam@154:    } else {
cannam@154:       int exc_length;
cannam@154:       /* Pitch-based PLC */
cannam@154:       const opus_val16 *window;
cannam@154:       opus_val16 *exc;
cannam@154:       opus_val16 fade = Q15ONE;
cannam@154:       int pitch_index;
cannam@154:       VARDECL(opus_val32, etmp);
cannam@154:       VARDECL(opus_val16, _exc);
cannam@154:       VARDECL(opus_val16, fir_tmp);
cannam@154: 
cannam@154:       if (loss_count == 0)
cannam@154:       {
cannam@154:          st->last_pitch_index = pitch_index = celt_plc_pitch_search(decode_mem, C, st->arch);
cannam@154:       } else {
cannam@154:          pitch_index = st->last_pitch_index;
cannam@154:          fade = QCONST16(.8f,15);
cannam@154:       }
cannam@154: 
cannam@154:       /* We want the excitation for 2 pitch periods in order to look for a
cannam@154:          decaying signal, but we can't get more than MAX_PERIOD. */
cannam@154:       exc_length = IMIN(2*pitch_index, MAX_PERIOD);
cannam@154: 
cannam@154:       ALLOC(etmp, overlap, opus_val32);
cannam@154:       ALLOC(_exc, MAX_PERIOD+LPC_ORDER, opus_val16);
cannam@154:       ALLOC(fir_tmp, exc_length, opus_val16);
cannam@154:       exc = _exc+LPC_ORDER;
cannam@154:       window = mode->window;
cannam@154:       c=0; do {
cannam@154:          opus_val16 decay;
cannam@154:          opus_val16 attenuation;
cannam@154:          opus_val32 S1=0;
cannam@154:          celt_sig *buf;
cannam@154:          int extrapolation_offset;
cannam@154:          int extrapolation_len;
cannam@154:          int j;
cannam@154: 
cannam@154:          buf = decode_mem[c];
cannam@154:          for (i=0;i<MAX_PERIOD+LPC_ORDER;i++)
cannam@154:             exc[i-LPC_ORDER] = ROUND16(buf[DECODE_BUFFER_SIZE-MAX_PERIOD-LPC_ORDER+i], SIG_SHIFT);
cannam@154: 
cannam@154:          if (loss_count == 0)
cannam@154:          {
cannam@154:             opus_val32 ac[LPC_ORDER+1];
cannam@154:             /* Compute LPC coefficients for the last MAX_PERIOD samples before
cannam@154:                the first loss so we can work in the excitation-filter domain. */
cannam@154:             _celt_autocorr(exc, ac, window, overlap,
cannam@154:                    LPC_ORDER, MAX_PERIOD, st->arch);
cannam@154:             /* Add a noise floor of -40 dB. */
cannam@154: #ifdef FIXED_POINT
cannam@154:             ac[0] += SHR32(ac[0],13);
cannam@154: #else
cannam@154:             ac[0] *= 1.0001f;
cannam@154: #endif
cannam@154:             /* Use lag windowing to stabilize the Levinson-Durbin recursion. */
cannam@154:             for (i=1;i<=LPC_ORDER;i++)
cannam@154:             {
cannam@154:                /*ac[i] *= exp(-.5*(2*M_PI*.002*i)*(2*M_PI*.002*i));*/
cannam@154: #ifdef FIXED_POINT
cannam@154:                ac[i] -= MULT16_32_Q15(2*i*i, ac[i]);
cannam@154: #else
cannam@154:                ac[i] -= ac[i]*(0.008f*0.008f)*i*i;
cannam@154: #endif
cannam@154:             }
cannam@154:             _celt_lpc(lpc+c*LPC_ORDER, ac, LPC_ORDER);
cannam@154: #ifdef FIXED_POINT
cannam@154:          /* For fixed-point, apply bandwidth expansion until we can guarantee that
cannam@154:             no overflow can happen in the IIR filter. This means:
cannam@154:             32768*sum(abs(filter)) < 2^31 */
cannam@154:          while (1) {
cannam@154:             opus_val16 tmp=Q15ONE;
cannam@154:             opus_val32 sum=QCONST16(1., SIG_SHIFT);
cannam@154:             for (i=0;i<LPC_ORDER;i++)
cannam@154:                sum += ABS16(lpc[c*LPC_ORDER+i]);
cannam@154:             if (sum < 65535) break;
cannam@154:             for (i=0;i<LPC_ORDER;i++)
cannam@154:             {
cannam@154:                tmp = MULT16_16_Q15(QCONST16(.99f,15), tmp);
cannam@154:                lpc[c*LPC_ORDER+i] = MULT16_16_Q15(lpc[c*LPC_ORDER+i], tmp);
cannam@154:             }
cannam@154:          }
cannam@154: #endif
cannam@154:          }
cannam@154:          /* Initialize the LPC history with the samples just before the start
cannam@154:             of the region for which we're computing the excitation. */
cannam@154:          {
cannam@154:             /* Compute the excitation for exc_length samples before the loss. We need the copy
cannam@154:                because celt_fir() cannot filter in-place. */
cannam@154:             celt_fir(exc+MAX_PERIOD-exc_length, lpc+c*LPC_ORDER,
cannam@154:                   fir_tmp, exc_length, LPC_ORDER, st->arch);
cannam@154:             OPUS_COPY(exc+MAX_PERIOD-exc_length, fir_tmp, exc_length);
cannam@154:          }
cannam@154: 
cannam@154:          /* Check if the waveform is decaying, and if so how fast.
cannam@154:             We do this to avoid adding energy when concealing in a segment
cannam@154:             with decaying energy. */
cannam@154:          {
cannam@154:             opus_val32 E1=1, E2=1;
cannam@154:             int decay_length;
cannam@154: #ifdef FIXED_POINT
cannam@154:             int shift = IMAX(0,2*celt_zlog2(celt_maxabs16(&exc[MAX_PERIOD-exc_length], exc_length))-20);
cannam@154: #endif
cannam@154:             decay_length = exc_length>>1;
cannam@154:             for (i=0;i<decay_length;i++)
cannam@154:             {
cannam@154:                opus_val16 e;
cannam@154:                e = exc[MAX_PERIOD-decay_length+i];
cannam@154:                E1 += SHR32(MULT16_16(e, e), shift);
cannam@154:                e = exc[MAX_PERIOD-2*decay_length+i];
cannam@154:                E2 += SHR32(MULT16_16(e, e), shift);
cannam@154:             }
cannam@154:             E1 = MIN32(E1, E2);
cannam@154:             decay = celt_sqrt(frac_div32(SHR32(E1, 1), E2));
cannam@154:          }
cannam@154: 
cannam@154:          /* Move the decoder memory one frame to the left to give us room to
cannam@154:             add the data for the new frame. We ignore the overlap that extends
cannam@154:             past the end of the buffer, because we aren't going to use it. */
cannam@154:          OPUS_MOVE(buf, buf+N, DECODE_BUFFER_SIZE-N);
cannam@154: 
cannam@154:          /* Extrapolate from the end of the excitation with a period of
cannam@154:             "pitch_index", scaling down each period by an additional factor of
cannam@154:             "decay". */
cannam@154:          extrapolation_offset = MAX_PERIOD-pitch_index;
cannam@154:          /* We need to extrapolate enough samples to cover a complete MDCT
cannam@154:             window (including overlap/2 samples on both sides). */
cannam@154:          extrapolation_len = N+overlap;
cannam@154:          /* We also apply fading if this is not the first loss. */
cannam@154:          attenuation = MULT16_16_Q15(fade, decay);
cannam@154:          for (i=j=0;i<extrapolation_len;i++,j++)
cannam@154:          {
cannam@154:             opus_val16 tmp;
cannam@154:             if (j >= pitch_index) {
cannam@154:                j -= pitch_index;
cannam@154:                attenuation = MULT16_16_Q15(attenuation, decay);
cannam@154:             }
cannam@154:             buf[DECODE_BUFFER_SIZE-N+i] =
cannam@154:                   SHL32(EXTEND32(MULT16_16_Q15(attenuation,
cannam@154:                         exc[extrapolation_offset+j])), SIG_SHIFT);
cannam@154:             /* Compute the energy of the previously decoded signal whose
cannam@154:                excitation we're copying. */
cannam@154:             tmp = ROUND16(
cannam@154:                   buf[DECODE_BUFFER_SIZE-MAX_PERIOD-N+extrapolation_offset+j],
cannam@154:                   SIG_SHIFT);
cannam@154:             S1 += SHR32(MULT16_16(tmp, tmp), 10);
cannam@154:          }
cannam@154:          {
cannam@154:             opus_val16 lpc_mem[LPC_ORDER];
cannam@154:             /* Copy the last decoded samples (prior to the overlap region) to
cannam@154:                synthesis filter memory so we can have a continuous signal. */
cannam@154:             for (i=0;i<LPC_ORDER;i++)
cannam@154:                lpc_mem[i] = ROUND16(buf[DECODE_BUFFER_SIZE-N-1-i], SIG_SHIFT);
cannam@154:             /* Apply the synthesis filter to convert the excitation back into
cannam@154:                the signal domain. */
cannam@154:             celt_iir(buf+DECODE_BUFFER_SIZE-N, lpc+c*LPC_ORDER,
cannam@154:                   buf+DECODE_BUFFER_SIZE-N, extrapolation_len, LPC_ORDER,
cannam@154:                   lpc_mem, st->arch);
cannam@154: #ifdef FIXED_POINT
cannam@154:             for (i=0; i < extrapolation_len; i++)
cannam@154:                buf[DECODE_BUFFER_SIZE-N+i] = SATURATE(buf[DECODE_BUFFER_SIZE-N+i], SIG_SAT);
cannam@154: #endif
cannam@154:          }
cannam@154: 
cannam@154:          /* Check if the synthesis energy is higher than expected, which can
cannam@154:             happen with the signal changes during our window. If so,
cannam@154:             attenuate. */
cannam@154:          {
cannam@154:             opus_val32 S2=0;
cannam@154:             for (i=0;i<extrapolation_len;i++)
cannam@154:             {
cannam@154:                opus_val16 tmp = ROUND16(buf[DECODE_BUFFER_SIZE-N+i], SIG_SHIFT);
cannam@154:                S2 += SHR32(MULT16_16(tmp, tmp), 10);
cannam@154:             }
cannam@154:             /* This checks for an "explosion" in the synthesis. */
cannam@154: #ifdef FIXED_POINT
cannam@154:             if (!(S1 > SHR32(S2,2)))
cannam@154: #else
cannam@154:             /* The float test is written this way to catch NaNs in the output
cannam@154:                of the IIR filter at the same time. */
cannam@154:             if (!(S1 > 0.2f*S2))
cannam@154: #endif
cannam@154:             {
cannam@154:                for (i=0;i<extrapolation_len;i++)
cannam@154:                   buf[DECODE_BUFFER_SIZE-N+i] = 0;
cannam@154:             } else if (S1 < S2)
cannam@154:             {
cannam@154:                opus_val16 ratio = celt_sqrt(frac_div32(SHR32(S1,1)+1,S2+1));
cannam@154:                for (i=0;i<overlap;i++)
cannam@154:                {
cannam@154:                   opus_val16 tmp_g = Q15ONE
cannam@154:                         - MULT16_16_Q15(window[i], Q15ONE-ratio);
cannam@154:                   buf[DECODE_BUFFER_SIZE-N+i] =
cannam@154:                         MULT16_32_Q15(tmp_g, buf[DECODE_BUFFER_SIZE-N+i]);
cannam@154:                }
cannam@154:                for (i=overlap;i<extrapolation_len;i++)
cannam@154:                {
cannam@154:                   buf[DECODE_BUFFER_SIZE-N+i] =
cannam@154:                         MULT16_32_Q15(ratio, buf[DECODE_BUFFER_SIZE-N+i]);
cannam@154:                }
cannam@154:             }
cannam@154:          }
cannam@154: 
cannam@154:          /* Apply the pre-filter to the MDCT overlap for the next frame because
cannam@154:             the post-filter will be re-applied in the decoder after the MDCT
cannam@154:             overlap. */
cannam@154:          comb_filter(etmp, buf+DECODE_BUFFER_SIZE,
cannam@154:               st->postfilter_period, st->postfilter_period, overlap,
cannam@154:               -st->postfilter_gain, -st->postfilter_gain,
cannam@154:               st->postfilter_tapset, st->postfilter_tapset, NULL, 0, st->arch);
cannam@154: 
cannam@154:          /* Simulate TDAC on the concealed audio so that it blends with the
cannam@154:             MDCT of the next frame. */
cannam@154:          for (i=0;i<overlap/2;i++)
cannam@154:          {
cannam@154:             buf[DECODE_BUFFER_SIZE+i] =
cannam@154:                MULT16_32_Q15(window[i], etmp[overlap-1-i])
cannam@154:                + MULT16_32_Q15(window[overlap-i-1], etmp[i]);
cannam@154:          }
cannam@154:       } while (++c<C);
cannam@154:    }
cannam@154: 
cannam@154:    st->loss_count = loss_count+1;
cannam@154: 
cannam@154:    RESTORE_STACK;
cannam@154: }
cannam@154: 
cannam@154: int celt_decode_with_ec(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data,
cannam@154:       int len, opus_val16 * OPUS_RESTRICT pcm, int frame_size, ec_dec *dec, int accum)
cannam@154: {
cannam@154:    int c, i, N;
cannam@154:    int spread_decision;
cannam@154:    opus_int32 bits;
cannam@154:    ec_dec _dec;
cannam@154: #ifdef NORM_ALIASING_HACK
cannam@154:    celt_norm *X;
cannam@154: #else
cannam@154:    VARDECL(celt_norm, X);
cannam@154: #endif
cannam@154:    VARDECL(int, fine_quant);
cannam@154:    VARDECL(int, pulses);
cannam@154:    VARDECL(int, cap);
cannam@154:    VARDECL(int, offsets);
cannam@154:    VARDECL(int, fine_priority);
cannam@154:    VARDECL(int, tf_res);
cannam@154:    VARDECL(unsigned char, collapse_masks);
cannam@154:    celt_sig *decode_mem[2];
cannam@154:    celt_sig *out_syn[2];
cannam@154:    opus_val16 *lpc;
cannam@154:    opus_val16 *oldBandE, *oldLogE, *oldLogE2, *backgroundLogE;
cannam@154: 
cannam@154:    int shortBlocks;
cannam@154:    int isTransient;
cannam@154:    int intra_ener;
cannam@154:    const int CC = st->channels;
cannam@154:    int LM, M;
cannam@154:    int start;
cannam@154:    int end;
cannam@154:    int effEnd;
cannam@154:    int codedBands;
cannam@154:    int alloc_trim;
cannam@154:    int postfilter_pitch;
cannam@154:    opus_val16 postfilter_gain;
cannam@154:    int intensity=0;
cannam@154:    int dual_stereo=0;
cannam@154:    opus_int32 total_bits;
cannam@154:    opus_int32 balance;
cannam@154:    opus_int32 tell;
cannam@154:    int dynalloc_logp;
cannam@154:    int postfilter_tapset;
cannam@154:    int anti_collapse_rsv;
cannam@154:    int anti_collapse_on=0;
cannam@154:    int silence;
cannam@154:    int C = st->stream_channels;
cannam@154:    const OpusCustomMode *mode;
cannam@154:    int nbEBands;
cannam@154:    int overlap;
cannam@154:    const opus_int16 *eBands;
cannam@154:    ALLOC_STACK;
cannam@154: 
cannam@154:    VALIDATE_CELT_DECODER(st);
cannam@154:    mode = st->mode;
cannam@154:    nbEBands = mode->nbEBands;
cannam@154:    overlap = mode->overlap;
cannam@154:    eBands = mode->eBands;
cannam@154:    start = st->start;
cannam@154:    end = st->end;
cannam@154:    frame_size *= st->downsample;
cannam@154: 
cannam@154:    lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+overlap)*CC);
cannam@154:    oldBandE = lpc+CC*LPC_ORDER;
cannam@154:    oldLogE = oldBandE + 2*nbEBands;
cannam@154:    oldLogE2 = oldLogE + 2*nbEBands;
cannam@154:    backgroundLogE = oldLogE2  + 2*nbEBands;
cannam@154: 
cannam@154: #ifdef CUSTOM_MODES
cannam@154:    if (st->signalling && data!=NULL)
cannam@154:    {
cannam@154:       int data0=data[0];
cannam@154:       /* Convert "standard mode" to Opus header */
cannam@154:       if (mode->Fs==48000 && mode->shortMdctSize==120)
cannam@154:       {
cannam@154:          data0 = fromOpus(data0);
cannam@154:          if (data0<0)
cannam@154:             return OPUS_INVALID_PACKET;
cannam@154:       }
cannam@154:       st->end = end = IMAX(1, mode->effEBands-2*(data0>>5));
cannam@154:       LM = (data0>>3)&0x3;
cannam@154:       C = 1 + ((data0>>2)&0x1);
cannam@154:       data++;
cannam@154:       len--;
cannam@154:       if (LM>mode->maxLM)
cannam@154:          return OPUS_INVALID_PACKET;
cannam@154:       if (frame_size < mode->shortMdctSize<<LM)
cannam@154:          return OPUS_BUFFER_TOO_SMALL;
cannam@154:       else
cannam@154:          frame_size = mode->shortMdctSize<<LM;
cannam@154:    } else {
cannam@154: #else
cannam@154:    {
cannam@154: #endif
cannam@154:       for (LM=0;LM<=mode->maxLM;LM++)
cannam@154:          if (mode->shortMdctSize<<LM==frame_size)
cannam@154:             break;
cannam@154:       if (LM>mode->maxLM)
cannam@154:          return OPUS_BAD_ARG;
cannam@154:    }
cannam@154:    M=1<<LM;
cannam@154: 
cannam@154:    if (len<0 || len>1275 || pcm==NULL)
cannam@154:       return OPUS_BAD_ARG;
cannam@154: 
cannam@154:    N = M*mode->shortMdctSize;
cannam@154:    c=0; do {
cannam@154:       decode_mem[c] = st->_decode_mem + c*(DECODE_BUFFER_SIZE+overlap);
cannam@154:       out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
cannam@154:    } while (++c<CC);
cannam@154: 
cannam@154:    effEnd = end;
cannam@154:    if (effEnd > mode->effEBands)
cannam@154:       effEnd = mode->effEBands;
cannam@154: 
cannam@154:    if (data == NULL || len<=1)
cannam@154:    {
cannam@154:       celt_decode_lost(st, N, LM);
cannam@154:       deemphasis(out_syn, pcm, N, CC, st->downsample, mode->preemph, st->preemph_memD, accum);
cannam@154:       RESTORE_STACK;
cannam@154:       return frame_size/st->downsample;
cannam@154:    }
cannam@154: 
cannam@154:    /* Check if there are at least two packets received consecutively before
cannam@154:     * turning on the pitch-based PLC */
cannam@154:    st->skip_plc = st->loss_count != 0;
cannam@154: 
cannam@154:    if (dec == NULL)
cannam@154:    {
cannam@154:       ec_dec_init(&_dec,(unsigned char*)data,len);
cannam@154:       dec = &_dec;
cannam@154:    }
cannam@154: 
cannam@154:    if (C==1)
cannam@154:    {
cannam@154:       for (i=0;i<nbEBands;i++)
cannam@154:          oldBandE[i]=MAX16(oldBandE[i],oldBandE[nbEBands+i]);
cannam@154:    }
cannam@154: 
cannam@154:    total_bits = len*8;
cannam@154:    tell = ec_tell(dec);
cannam@154: 
cannam@154:    if (tell >= total_bits)
cannam@154:       silence = 1;
cannam@154:    else if (tell==1)
cannam@154:       silence = ec_dec_bit_logp(dec, 15);
cannam@154:    else
cannam@154:       silence = 0;
cannam@154:    if (silence)
cannam@154:    {
cannam@154:       /* Pretend we've read all the remaining bits */
cannam@154:       tell = len*8;
cannam@154:       dec->nbits_total+=tell-ec_tell(dec);
cannam@154:    }
cannam@154: 
cannam@154:    postfilter_gain = 0;
cannam@154:    postfilter_pitch = 0;
cannam@154:    postfilter_tapset = 0;
cannam@154:    if (start==0 && tell+16 <= total_bits)
cannam@154:    {
cannam@154:       if(ec_dec_bit_logp(dec, 1))
cannam@154:       {
cannam@154:          int qg, octave;
cannam@154:          octave = ec_dec_uint(dec, 6);
cannam@154:          postfilter_pitch = (16<<octave)+ec_dec_bits(dec, 4+octave)-1;
cannam@154:          qg = ec_dec_bits(dec, 3);
cannam@154:          if (ec_tell(dec)+2<=total_bits)
cannam@154:             postfilter_tapset = ec_dec_icdf(dec, tapset_icdf, 2);
cannam@154:          postfilter_gain = QCONST16(.09375f,15)*(qg+1);
cannam@154:       }
cannam@154:       tell = ec_tell(dec);
cannam@154:    }
cannam@154: 
cannam@154:    if (LM > 0 && tell+3 <= total_bits)
cannam@154:    {
cannam@154:       isTransient = ec_dec_bit_logp(dec, 3);
cannam@154:       tell = ec_tell(dec);
cannam@154:    }
cannam@154:    else
cannam@154:       isTransient = 0;
cannam@154: 
cannam@154:    if (isTransient)
cannam@154:       shortBlocks = M;
cannam@154:    else
cannam@154:       shortBlocks = 0;
cannam@154: 
cannam@154:    /* Decode the global flags (first symbols in the stream) */
cannam@154:    intra_ener = tell+3<=total_bits ? ec_dec_bit_logp(dec, 3) : 0;
cannam@154:    /* Get band energies */
cannam@154:    unquant_coarse_energy(mode, start, end, oldBandE,
cannam@154:          intra_ener, dec, C, LM);
cannam@154: 
cannam@154:    ALLOC(tf_res, nbEBands, int);
cannam@154:    tf_decode(start, end, isTransient, tf_res, LM, dec);
cannam@154: 
cannam@154:    tell = ec_tell(dec);
cannam@154:    spread_decision = SPREAD_NORMAL;
cannam@154:    if (tell+4 <= total_bits)
cannam@154:       spread_decision = ec_dec_icdf(dec, spread_icdf, 5);
cannam@154: 
cannam@154:    ALLOC(cap, nbEBands, int);
cannam@154: 
cannam@154:    init_caps(mode,cap,LM,C);
cannam@154: 
cannam@154:    ALLOC(offsets, nbEBands, int);
cannam@154: 
cannam@154:    dynalloc_logp = 6;
cannam@154:    total_bits<<=BITRES;
cannam@154:    tell = ec_tell_frac(dec);
cannam@154:    for (i=start;i<end;i++)
cannam@154:    {
cannam@154:       int width, quanta;
cannam@154:       int dynalloc_loop_logp;
cannam@154:       int boost;
cannam@154:       width = C*(eBands[i+1]-eBands[i])<<LM;
cannam@154:       /* quanta is 6 bits, but no more than 1 bit/sample
cannam@154:          and no less than 1/8 bit/sample */
cannam@154:       quanta = IMIN(width<<BITRES, IMAX(6<<BITRES, width));
cannam@154:       dynalloc_loop_logp = dynalloc_logp;
cannam@154:       boost = 0;
cannam@154:       while (tell+(dynalloc_loop_logp<<BITRES) < total_bits && boost < cap[i])
cannam@154:       {
cannam@154:          int flag;
cannam@154:          flag = ec_dec_bit_logp(dec, dynalloc_loop_logp);
cannam@154:          tell = ec_tell_frac(dec);
cannam@154:          if (!flag)
cannam@154:             break;
cannam@154:          boost += quanta;
cannam@154:          total_bits -= quanta;
cannam@154:          dynalloc_loop_logp = 1;
cannam@154:       }
cannam@154:       offsets[i] = boost;
cannam@154:       /* Making dynalloc more likely */
cannam@154:       if (boost>0)
cannam@154:          dynalloc_logp = IMAX(2, dynalloc_logp-1);
cannam@154:    }
cannam@154: 
cannam@154:    ALLOC(fine_quant, nbEBands, int);
cannam@154:    alloc_trim = tell+(6<<BITRES) <= total_bits ?
cannam@154:          ec_dec_icdf(dec, trim_icdf, 7) : 5;
cannam@154: 
cannam@154:    bits = (((opus_int32)len*8)<<BITRES) - ec_tell_frac(dec) - 1;
cannam@154:    anti_collapse_rsv = isTransient&&LM>=2&&bits>=((LM+2)<<BITRES) ? (1<<BITRES) : 0;
cannam@154:    bits -= anti_collapse_rsv;
cannam@154: 
cannam@154:    ALLOC(pulses, nbEBands, int);
cannam@154:    ALLOC(fine_priority, nbEBands, int);
cannam@154: 
cannam@154:    codedBands = clt_compute_allocation(mode, start, end, offsets, cap,
cannam@154:          alloc_trim, &intensity, &dual_stereo, bits, &balance, pulses,
cannam@154:          fine_quant, fine_priority, C, LM, dec, 0, 0, 0);
cannam@154: 
cannam@154:    unquant_fine_energy(mode, start, end, oldBandE, fine_quant, dec, C);
cannam@154: 
cannam@154:    c=0; do {
cannam@154:       OPUS_MOVE(decode_mem[c], decode_mem[c]+N, DECODE_BUFFER_SIZE-N+overlap/2);
cannam@154:    } while (++c<CC);
cannam@154: 
cannam@154:    /* Decode fixed codebook */
cannam@154:    ALLOC(collapse_masks, C*nbEBands, unsigned char);
cannam@154: 
cannam@154: #ifdef NORM_ALIASING_HACK
cannam@154:    /* This is an ugly hack that breaks aliasing rules and would be easily broken,
cannam@154:       but it saves almost 4kB of stack. */
cannam@154:    X = (celt_norm*)(out_syn[CC-1]+overlap/2);
cannam@154: #else
cannam@154:    ALLOC(X, C*N, celt_norm);   /**< Interleaved normalised MDCTs */
cannam@154: #endif
cannam@154: 
cannam@154:    quant_all_bands(0, mode, start, end, X, C==2 ? X+N : NULL, collapse_masks,
cannam@154:          NULL, pulses, shortBlocks, spread_decision, dual_stereo, intensity, tf_res,
cannam@154:          len*(8<<BITRES)-anti_collapse_rsv, balance, dec, LM, codedBands, &st->rng, 0,
cannam@154:          st->arch, st->disable_inv);
cannam@154: 
cannam@154:    if (anti_collapse_rsv > 0)
cannam@154:    {
cannam@154:       anti_collapse_on = ec_dec_bits(dec, 1);
cannam@154:    }
cannam@154: 
cannam@154:    unquant_energy_finalise(mode, start, end, oldBandE,
cannam@154:          fine_quant, fine_priority, len*8-ec_tell(dec), dec, C);
cannam@154: 
cannam@154:    if (anti_collapse_on)
cannam@154:       anti_collapse(mode, X, collapse_masks, LM, C, N,
cannam@154:             start, end, oldBandE, oldLogE, oldLogE2, pulses, st->rng, st->arch);
cannam@154: 
cannam@154:    if (silence)
cannam@154:    {
cannam@154:       for (i=0;i<C*nbEBands;i++)
cannam@154:          oldBandE[i] = -QCONST16(28.f,DB_SHIFT);
cannam@154:    }
cannam@154: 
cannam@154:    celt_synthesis(mode, X, out_syn, oldBandE, start, effEnd,
cannam@154:                   C, CC, isTransient, LM, st->downsample, silence, st->arch);
cannam@154: 
cannam@154:    c=0; do {
cannam@154:       st->postfilter_period=IMAX(st->postfilter_period, COMBFILTER_MINPERIOD);
cannam@154:       st->postfilter_period_old=IMAX(st->postfilter_period_old, COMBFILTER_MINPERIOD);
cannam@154:       comb_filter(out_syn[c], out_syn[c], st->postfilter_period_old, st->postfilter_period, mode->shortMdctSize,
cannam@154:             st->postfilter_gain_old, st->postfilter_gain, st->postfilter_tapset_old, st->postfilter_tapset,
cannam@154:             mode->window, overlap, st->arch);
cannam@154:       if (LM!=0)
cannam@154:          comb_filter(out_syn[c]+mode->shortMdctSize, out_syn[c]+mode->shortMdctSize, st->postfilter_period, postfilter_pitch, N-mode->shortMdctSize,
cannam@154:                st->postfilter_gain, postfilter_gain, st->postfilter_tapset, postfilter_tapset,
cannam@154:                mode->window, overlap, st->arch);
cannam@154: 
cannam@154:    } while (++c<CC);
cannam@154:    st->postfilter_period_old = st->postfilter_period;
cannam@154:    st->postfilter_gain_old = st->postfilter_gain;
cannam@154:    st->postfilter_tapset_old = st->postfilter_tapset;
cannam@154:    st->postfilter_period = postfilter_pitch;
cannam@154:    st->postfilter_gain = postfilter_gain;
cannam@154:    st->postfilter_tapset = postfilter_tapset;
cannam@154:    if (LM!=0)
cannam@154:    {
cannam@154:       st->postfilter_period_old = st->postfilter_period;
cannam@154:       st->postfilter_gain_old = st->postfilter_gain;
cannam@154:       st->postfilter_tapset_old = st->postfilter_tapset;
cannam@154:    }
cannam@154: 
cannam@154:    if (C==1)
cannam@154:       OPUS_COPY(&oldBandE[nbEBands], oldBandE, nbEBands);
cannam@154: 
cannam@154:    /* In case start or end were to change */
cannam@154:    if (!isTransient)
cannam@154:    {
cannam@154:       opus_val16 max_background_increase;
cannam@154:       OPUS_COPY(oldLogE2, oldLogE, 2*nbEBands);
cannam@154:       OPUS_COPY(oldLogE, oldBandE, 2*nbEBands);
cannam@154:       /* In normal circumstances, we only allow the noise floor to increase by
cannam@154:          up to 2.4 dB/second, but when we're in DTX, we allow up to 6 dB
cannam@154:          increase for each update.*/
cannam@154:       if (st->loss_count < 10)
cannam@154:          max_background_increase = M*QCONST16(0.001f,DB_SHIFT);
cannam@154:       else
cannam@154:          max_background_increase = QCONST16(1.f,DB_SHIFT);
cannam@154:       for (i=0;i<2*nbEBands;i++)
cannam@154:          backgroundLogE[i] = MIN16(backgroundLogE[i] + max_background_increase, oldBandE[i]);
cannam@154:    } else {
cannam@154:       for (i=0;i<2*nbEBands;i++)
cannam@154:          oldLogE[i] = MIN16(oldLogE[i], oldBandE[i]);
cannam@154:    }
cannam@154:    c=0; do
cannam@154:    {
cannam@154:       for (i=0;i<start;i++)
cannam@154:       {
cannam@154:          oldBandE[c*nbEBands+i]=0;
cannam@154:          oldLogE[c*nbEBands+i]=oldLogE2[c*nbEBands+i]=-QCONST16(28.f,DB_SHIFT);
cannam@154:       }
cannam@154:       for (i=end;i<nbEBands;i++)
cannam@154:       {
cannam@154:          oldBandE[c*nbEBands+i]=0;
cannam@154:          oldLogE[c*nbEBands+i]=oldLogE2[c*nbEBands+i]=-QCONST16(28.f,DB_SHIFT);
cannam@154:       }
cannam@154:    } while (++c<2);
cannam@154:    st->rng = dec->rng;
cannam@154: 
cannam@154:    deemphasis(out_syn, pcm, N, CC, st->downsample, mode->preemph, st->preemph_memD, accum);
cannam@154:    st->loss_count = 0;
cannam@154:    RESTORE_STACK;
cannam@154:    if (ec_tell(dec) > 8*len)
cannam@154:       return OPUS_INTERNAL_ERROR;
cannam@154:    if(ec_get_error(dec))
cannam@154:       st->error = 1;
cannam@154:    return frame_size/st->downsample;
cannam@154: }
cannam@154: 
cannam@154: 
cannam@154: #ifdef CUSTOM_MODES
cannam@154: 
cannam@154: #ifdef FIXED_POINT
cannam@154: int opus_custom_decode(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, opus_int16 * OPUS_RESTRICT pcm, int frame_size)
cannam@154: {
cannam@154:    return celt_decode_with_ec(st, data, len, pcm, frame_size, NULL, 0);
cannam@154: }
cannam@154: 
cannam@154: #ifndef DISABLE_FLOAT_API
cannam@154: int opus_custom_decode_float(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, float * OPUS_RESTRICT pcm, int frame_size)
cannam@154: {
cannam@154:    int j, ret, C, N;
cannam@154:    VARDECL(opus_int16, out);
cannam@154:    ALLOC_STACK;
cannam@154: 
cannam@154:    if (pcm==NULL)
cannam@154:       return OPUS_BAD_ARG;
cannam@154: 
cannam@154:    C = st->channels;
cannam@154:    N = frame_size;
cannam@154: 
cannam@154:    ALLOC(out, C*N, opus_int16);
cannam@154:    ret=celt_decode_with_ec(st, data, len, out, frame_size, NULL, 0);
cannam@154:    if (ret>0)
cannam@154:       for (j=0;j<C*ret;j++)
cannam@154:          pcm[j]=out[j]*(1.f/32768.f);
cannam@154: 
cannam@154:    RESTORE_STACK;
cannam@154:    return ret;
cannam@154: }
cannam@154: #endif /* DISABLE_FLOAT_API */
cannam@154: 
cannam@154: #else
cannam@154: 
cannam@154: int opus_custom_decode_float(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, float * OPUS_RESTRICT pcm, int frame_size)
cannam@154: {
cannam@154:    return celt_decode_with_ec(st, data, len, pcm, frame_size, NULL, 0);
cannam@154: }
cannam@154: 
cannam@154: int opus_custom_decode(CELTDecoder * OPUS_RESTRICT st, const unsigned char *data, int len, opus_int16 * OPUS_RESTRICT pcm, int frame_size)
cannam@154: {
cannam@154:    int j, ret, C, N;
cannam@154:    VARDECL(celt_sig, out);
cannam@154:    ALLOC_STACK;
cannam@154: 
cannam@154:    if (pcm==NULL)
cannam@154:       return OPUS_BAD_ARG;
cannam@154: 
cannam@154:    C = st->channels;
cannam@154:    N = frame_size;
cannam@154:    ALLOC(out, C*N, celt_sig);
cannam@154: 
cannam@154:    ret=celt_decode_with_ec(st, data, len, out, frame_size, NULL, 0);
cannam@154: 
cannam@154:    if (ret>0)
cannam@154:       for (j=0;j<C*ret;j++)
cannam@154:          pcm[j] = FLOAT2INT16 (out[j]);
cannam@154: 
cannam@154:    RESTORE_STACK;
cannam@154:    return ret;
cannam@154: }
cannam@154: 
cannam@154: #endif
cannam@154: #endif /* CUSTOM_MODES */
cannam@154: 
cannam@154: int opus_custom_decoder_ctl(CELTDecoder * OPUS_RESTRICT st, int request, ...)
cannam@154: {
cannam@154:    va_list ap;
cannam@154: 
cannam@154:    va_start(ap, request);
cannam@154:    switch (request)
cannam@154:    {
cannam@154:       case CELT_SET_START_BAND_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 value = va_arg(ap, opus_int32);
cannam@154:          if (value<0 || value>=st->mode->nbEBands)
cannam@154:             goto bad_arg;
cannam@154:          st->start = value;
cannam@154:       }
cannam@154:       break;
cannam@154:       case CELT_SET_END_BAND_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 value = va_arg(ap, opus_int32);
cannam@154:          if (value<1 || value>st->mode->nbEBands)
cannam@154:             goto bad_arg;
cannam@154:          st->end = value;
cannam@154:       }
cannam@154:       break;
cannam@154:       case CELT_SET_CHANNELS_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 value = va_arg(ap, opus_int32);
cannam@154:          if (value<1 || value>2)
cannam@154:             goto bad_arg;
cannam@154:          st->stream_channels = value;
cannam@154:       }
cannam@154:       break;
cannam@154:       case CELT_GET_AND_CLEAR_ERROR_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 *value = va_arg(ap, opus_int32*);
cannam@154:          if (value==NULL)
cannam@154:             goto bad_arg;
cannam@154:          *value=st->error;
cannam@154:          st->error = 0;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_GET_LOOKAHEAD_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 *value = va_arg(ap, opus_int32*);
cannam@154:          if (value==NULL)
cannam@154:             goto bad_arg;
cannam@154:          *value = st->overlap/st->downsample;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_RESET_STATE:
cannam@154:       {
cannam@154:          int i;
cannam@154:          opus_val16 *lpc, *oldBandE, *oldLogE, *oldLogE2;
cannam@154:          lpc = (opus_val16*)(st->_decode_mem+(DECODE_BUFFER_SIZE+st->overlap)*st->channels);
cannam@154:          oldBandE = lpc+st->channels*LPC_ORDER;
cannam@154:          oldLogE = oldBandE + 2*st->mode->nbEBands;
cannam@154:          oldLogE2 = oldLogE + 2*st->mode->nbEBands;
cannam@154:          OPUS_CLEAR((char*)&st->DECODER_RESET_START,
cannam@154:                opus_custom_decoder_get_size(st->mode, st->channels)-
cannam@154:                ((char*)&st->DECODER_RESET_START - (char*)st));
cannam@154:          for (i=0;i<2*st->mode->nbEBands;i++)
cannam@154:             oldLogE[i]=oldLogE2[i]=-QCONST16(28.f,DB_SHIFT);
cannam@154:          st->skip_plc = 1;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_GET_PITCH_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 *value = va_arg(ap, opus_int32*);
cannam@154:          if (value==NULL)
cannam@154:             goto bad_arg;
cannam@154:          *value = st->postfilter_period;
cannam@154:       }
cannam@154:       break;
cannam@154:       case CELT_GET_MODE_REQUEST:
cannam@154:       {
cannam@154:          const CELTMode ** value = va_arg(ap, const CELTMode**);
cannam@154:          if (value==0)
cannam@154:             goto bad_arg;
cannam@154:          *value=st->mode;
cannam@154:       }
cannam@154:       break;
cannam@154:       case CELT_SET_SIGNALLING_REQUEST:
cannam@154:       {
cannam@154:          opus_int32 value = va_arg(ap, opus_int32);
cannam@154:          st->signalling = value;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_GET_FINAL_RANGE_REQUEST:
cannam@154:       {
cannam@154:          opus_uint32 * value = va_arg(ap, opus_uint32 *);
cannam@154:          if (value==0)
cannam@154:             goto bad_arg;
cannam@154:          *value=st->rng;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_SET_PHASE_INVERSION_DISABLED_REQUEST:
cannam@154:       {
cannam@154:           opus_int32 value = va_arg(ap, opus_int32);
cannam@154:           if(value<0 || value>1)
cannam@154:           {
cannam@154:              goto bad_arg;
cannam@154:           }
cannam@154:           st->disable_inv = value;
cannam@154:       }
cannam@154:       break;
cannam@154:       case OPUS_GET_PHASE_INVERSION_DISABLED_REQUEST:
cannam@154:       {
cannam@154:           opus_int32 *value = va_arg(ap, opus_int32*);
cannam@154:           if (!value)
cannam@154:           {
cannam@154:              goto bad_arg;
cannam@154:           }
cannam@154:           *value = st->disable_inv;
cannam@154:       }
cannam@154:       break;
cannam@154:       default:
cannam@154:          goto bad_request;
cannam@154:    }
cannam@154:    va_end(ap);
cannam@154:    return OPUS_OK;
cannam@154: bad_arg:
cannam@154:    va_end(ap);
cannam@154:    return OPUS_BAD_ARG;
cannam@154: bad_request:
cannam@154:       va_end(ap);
cannam@154:   return OPUS_UNIMPLEMENTED;
cannam@154: }