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      1 /* Copyright (c) 2010-2011 Xiph.Org Foundation, Skype Limited
      2    Written by Jean-Marc Valin and Koen Vos */
      3 /*
      4    Redistribution and use in source and binary forms, with or without
      5    modification, are permitted provided that the following conditions
      6    are met:
      7 
      8    - Redistributions of source code must retain the above copyright
      9    notice, this list of conditions and the following disclaimer.
     10 
     11    - Redistributions in binary form must reproduce the above copyright
     12    notice, this list of conditions and the following disclaimer in the
     13    documentation and/or other materials provided with the distribution.
     14 
     15    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     16    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     17    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     18    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
     19    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     20    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     21    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     22    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     23    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     24    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     25    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26 */
     27 
     28 #ifdef HAVE_CONFIG_H
     29 #include "config.h"
     30 #endif
     31 
     32 #include <stdarg.h>
     33 #include "celt.h"
     34 #include "entenc.h"
     35 #include "modes.h"
     36 #include "API.h"
     37 #include "stack_alloc.h"
     38 #include "float_cast.h"
     39 #include "opus.h"
     40 #include "arch.h"
     41 #include "pitch.h"
     42 #include "opus_private.h"
     43 #include "os_support.h"
     44 #include "cpu_support.h"
     45 #include "analysis.h"
     46 #include "mathops.h"
     47 #include "tuning_parameters.h"
     48 #ifdef FIXED_POINT
     49 #include "fixed/structs_FIX.h"
     50 #else
     51 #include "float/structs_FLP.h"
     52 #endif
     53 
     54 #define MAX_ENCODER_BUFFER 480
     55 
     56 typedef struct {
     57    opus_val32 XX, XY, YY;
     58    opus_val16 smoothed_width;
     59    opus_val16 max_follower;
     60 } StereoWidthState;
     61 
     62 struct OpusEncoder {
     63     int          celt_enc_offset;
     64     int          silk_enc_offset;
     65     silk_EncControlStruct silk_mode;
     66     int          application;
     67     int          channels;
     68     int          delay_compensation;
     69     int          force_channels;
     70     int          signal_type;
     71     int          user_bandwidth;
     72     int          max_bandwidth;
     73     int          user_forced_mode;
     74     int          voice_ratio;
     75     opus_int32   Fs;
     76     int          use_vbr;
     77     int          vbr_constraint;
     78     int          variable_duration;
     79     opus_int32   bitrate_bps;
     80     opus_int32   user_bitrate_bps;
     81     int          lsb_depth;
     82     int          encoder_buffer;
     83     int          lfe;
     84     int          arch;
     85 #ifndef DISABLE_FLOAT_API
     86     TonalityAnalysisState analysis;
     87 #endif
     88 
     89 #define OPUS_ENCODER_RESET_START stream_channels
     90     int          stream_channels;
     91     opus_int16   hybrid_stereo_width_Q14;
     92     opus_int32   variable_HP_smth2_Q15;
     93     opus_val16   prev_HB_gain;
     94     opus_val32   hp_mem[4];
     95     int          mode;
     96     int          prev_mode;
     97     int          prev_channels;
     98     int          prev_framesize;
     99     int          bandwidth;
    100     int          silk_bw_switch;
    101     /* Sampling rate (at the API level) */
    102     int          first;
    103     opus_val16 * energy_masking;
    104     StereoWidthState width_mem;
    105     opus_val16   delay_buffer[MAX_ENCODER_BUFFER*2];
    106 #ifndef DISABLE_FLOAT_API
    107     int          detected_bandwidth;
    108 #endif
    109     opus_uint32  rangeFinal;
    110 };
    111 
    112 /* Transition tables for the voice and music. First column is the
    113    middle (memoriless) threshold. The second column is the hysteresis
    114    (difference with the middle) */
    115 static const opus_int32 mono_voice_bandwidth_thresholds[8] = {
    116         11000, 1000, /* NB<->MB */
    117         14000, 1000, /* MB<->WB */
    118         17000, 1000, /* WB<->SWB */
    119         21000, 2000, /* SWB<->FB */
    120 };
    121 static const opus_int32 mono_music_bandwidth_thresholds[8] = {
    122         12000, 1000, /* NB<->MB */
    123         15000, 1000, /* MB<->WB */
    124         18000, 2000, /* WB<->SWB */
    125         22000, 2000, /* SWB<->FB */
    126 };
    127 static const opus_int32 stereo_voice_bandwidth_thresholds[8] = {
    128         11000, 1000, /* NB<->MB */
    129         14000, 1000, /* MB<->WB */
    130         21000, 2000, /* WB<->SWB */
    131         28000, 2000, /* SWB<->FB */
    132 };
    133 static const opus_int32 stereo_music_bandwidth_thresholds[8] = {
    134         12000, 1000, /* NB<->MB */
    135         18000, 2000, /* MB<->WB */
    136         21000, 2000, /* WB<->SWB */
    137         30000, 2000, /* SWB<->FB */
    138 };
    139 /* Threshold bit-rates for switching between mono and stereo */
    140 static const opus_int32 stereo_voice_threshold = 30000;
    141 static const opus_int32 stereo_music_threshold = 30000;
    142 
    143 /* Threshold bit-rate for switching between SILK/hybrid and CELT-only */
    144 static const opus_int32 mode_thresholds[2][2] = {
    145       /* voice */ /* music */
    146       {  64000,      16000}, /* mono */
    147       {  36000,      16000}, /* stereo */
    148 };
    149 
    150 int opus_encoder_get_size(int channels)
    151 {
    152     int silkEncSizeBytes, celtEncSizeBytes;
    153     int ret;
    154     if (channels<1 || channels > 2)
    155         return 0;
    156     ret = silk_Get_Encoder_Size( &silkEncSizeBytes );
    157     if (ret)
    158         return 0;
    159     silkEncSizeBytes = align(silkEncSizeBytes);
    160     celtEncSizeBytes = celt_encoder_get_size(channels);
    161     return align(sizeof(OpusEncoder))+silkEncSizeBytes+celtEncSizeBytes;
    162 }
    163 
    164 int opus_encoder_init(OpusEncoder* st, opus_int32 Fs, int channels, int application)
    165 {
    166     void *silk_enc;
    167     CELTEncoder *celt_enc;
    168     int err;
    169     int ret, silkEncSizeBytes;
    170 
    171    if((Fs!=48000&&Fs!=24000&&Fs!=16000&&Fs!=12000&&Fs!=8000)||(channels!=1&&channels!=2)||
    172         (application != OPUS_APPLICATION_VOIP && application != OPUS_APPLICATION_AUDIO
    173         && application != OPUS_APPLICATION_RESTRICTED_LOWDELAY))
    174         return OPUS_BAD_ARG;
    175 
    176     OPUS_CLEAR((char*)st, opus_encoder_get_size(channels));
    177     /* Create SILK encoder */
    178     ret = silk_Get_Encoder_Size( &silkEncSizeBytes );
    179     if (ret)
    180         return OPUS_BAD_ARG;
    181     silkEncSizeBytes = align(silkEncSizeBytes);
    182     st->silk_enc_offset = align(sizeof(OpusEncoder));
    183     st->celt_enc_offset = st->silk_enc_offset+silkEncSizeBytes;
    184     silk_enc = (char*)st+st->silk_enc_offset;
    185     celt_enc = (CELTEncoder*)((char*)st+st->celt_enc_offset);
    186 
    187     st->stream_channels = st->channels = channels;
    188 
    189     st->Fs = Fs;
    190 
    191     st->arch = opus_select_arch();
    192 
    193     ret = silk_InitEncoder( silk_enc, st->arch, &st->silk_mode );
    194     if(ret)return OPUS_INTERNAL_ERROR;
    195 
    196     /* default SILK parameters */
    197     st->silk_mode.nChannelsAPI              = channels;
    198     st->silk_mode.nChannelsInternal         = channels;
    199     st->silk_mode.API_sampleRate            = st->Fs;
    200     st->silk_mode.maxInternalSampleRate     = 16000;
    201     st->silk_mode.minInternalSampleRate     = 8000;
    202     st->silk_mode.desiredInternalSampleRate = 16000;
    203     st->silk_mode.payloadSize_ms            = 20;
    204     st->silk_mode.bitRate                   = 25000;
    205     st->silk_mode.packetLossPercentage      = 0;
    206     st->silk_mode.complexity                = 9;
    207     st->silk_mode.useInBandFEC              = 0;
    208     st->silk_mode.useDTX                    = 0;
    209     st->silk_mode.useCBR                    = 0;
    210     st->silk_mode.reducedDependency         = 0;
    211 
    212     /* Create CELT encoder */
    213     /* Initialize CELT encoder */
    214     err = celt_encoder_init(celt_enc, Fs, channels, st->arch);
    215     if(err!=OPUS_OK)return OPUS_INTERNAL_ERROR;
    216 
    217     celt_encoder_ctl(celt_enc, CELT_SET_SIGNALLING(0));
    218     celt_encoder_ctl(celt_enc, OPUS_SET_COMPLEXITY(st->silk_mode.complexity));
    219 
    220     st->use_vbr = 1;
    221     /* Makes constrained VBR the default (safer for real-time use) */
    222     st->vbr_constraint = 1;
    223     st->user_bitrate_bps = OPUS_AUTO;
    224     st->bitrate_bps = 3000+Fs*channels;
    225     st->application = application;
    226     st->signal_type = OPUS_AUTO;
    227     st->user_bandwidth = OPUS_AUTO;
    228     st->max_bandwidth = OPUS_BANDWIDTH_FULLBAND;
    229     st->force_channels = OPUS_AUTO;
    230     st->user_forced_mode = OPUS_AUTO;
    231     st->voice_ratio = -1;
    232     st->encoder_buffer = st->Fs/100;
    233     st->lsb_depth = 24;
    234     st->variable_duration = OPUS_FRAMESIZE_ARG;
    235 
    236     /* Delay compensation of 4 ms (2.5 ms for SILK's extra look-ahead
    237        + 1.5 ms for SILK resamplers and stereo prediction) */
    238     st->delay_compensation = st->Fs/250;
    239 
    240     st->hybrid_stereo_width_Q14 = 1 << 14;
    241     st->prev_HB_gain = Q15ONE;
    242     st->variable_HP_smth2_Q15 = silk_LSHIFT( silk_lin2log( VARIABLE_HP_MIN_CUTOFF_HZ ), 8 );
    243     st->first = 1;
    244     st->mode = MODE_HYBRID;
    245     st->bandwidth = OPUS_BANDWIDTH_FULLBAND;
    246 
    247 #ifndef DISABLE_FLOAT_API
    248     tonality_analysis_init(&st->analysis);
    249 #endif
    250 
    251     return OPUS_OK;
    252 }
    253 
    254 static unsigned char gen_toc(int mode, int framerate, int bandwidth, int channels)
    255 {
    256    int period;
    257    unsigned char toc;
    258    period = 0;
    259    while (framerate < 400)
    260    {
    261        framerate <<= 1;
    262        period++;
    263    }
    264    if (mode == MODE_SILK_ONLY)
    265    {
    266        toc = (bandwidth-OPUS_BANDWIDTH_NARROWBAND)<<5;
    267        toc |= (period-2)<<3;
    268    } else if (mode == MODE_CELT_ONLY)
    269    {
    270        int tmp = bandwidth-OPUS_BANDWIDTH_MEDIUMBAND;
    271        if (tmp < 0)
    272            tmp = 0;
    273        toc = 0x80;
    274        toc |= tmp << 5;
    275        toc |= period<<3;
    276    } else /* Hybrid */
    277    {
    278        toc = 0x60;
    279        toc |= (bandwidth-OPUS_BANDWIDTH_SUPERWIDEBAND)<<4;
    280        toc |= (period-2)<<3;
    281    }
    282    toc |= (channels==2)<<2;
    283    return toc;
    284 }
    285 
    286 #ifndef FIXED_POINT
    287 static void silk_biquad_float(
    288     const opus_val16      *in,            /* I:    Input signal                   */
    289     const opus_int32      *B_Q28,         /* I:    MA coefficients [3]            */
    290     const opus_int32      *A_Q28,         /* I:    AR coefficients [2]            */
    291     opus_val32            *S,             /* I/O:  State vector [2]               */
    292     opus_val16            *out,           /* O:    Output signal                  */
    293     const opus_int32      len,            /* I:    Signal length (must be even)   */
    294     int stride
    295 )
    296 {
    297     /* DIRECT FORM II TRANSPOSED (uses 2 element state vector) */
    298     opus_int   k;
    299     opus_val32 vout;
    300     opus_val32 inval;
    301     opus_val32 A[2], B[3];
    302 
    303     A[0] = (opus_val32)(A_Q28[0] * (1.f/((opus_int32)1<<28)));
    304     A[1] = (opus_val32)(A_Q28[1] * (1.f/((opus_int32)1<<28)));
    305     B[0] = (opus_val32)(B_Q28[0] * (1.f/((opus_int32)1<<28)));
    306     B[1] = (opus_val32)(B_Q28[1] * (1.f/((opus_int32)1<<28)));
    307     B[2] = (opus_val32)(B_Q28[2] * (1.f/((opus_int32)1<<28)));
    308 
    309     /* Negate A_Q28 values and split in two parts */
    310 
    311     for( k = 0; k < len; k++ ) {
    312         /* S[ 0 ], S[ 1 ]: Q12 */
    313         inval = in[ k*stride ];
    314         vout = S[ 0 ] + B[0]*inval;
    315 
    316         S[ 0 ] = S[1] - vout*A[0] + B[1]*inval;
    317 
    318         S[ 1 ] = - vout*A[1] + B[2]*inval + VERY_SMALL;
    319 
    320         /* Scale back to Q0 and saturate */
    321         out[ k*stride ] = vout;
    322     }
    323 }
    324 #endif
    325 
    326 static void hp_cutoff(const opus_val16 *in, opus_int32 cutoff_Hz, opus_val16 *out, opus_val32 *hp_mem, int len, int channels, opus_int32 Fs)
    327 {
    328    opus_int32 B_Q28[ 3 ], A_Q28[ 2 ];
    329    opus_int32 Fc_Q19, r_Q28, r_Q22;
    330 
    331    silk_assert( cutoff_Hz <= silk_int32_MAX / SILK_FIX_CONST( 1.5 * 3.14159 / 1000, 19 ) );
    332    Fc_Q19 = silk_DIV32_16( silk_SMULBB( SILK_FIX_CONST( 1.5 * 3.14159 / 1000, 19 ), cutoff_Hz ), Fs/1000 );
    333    silk_assert( Fc_Q19 > 0 && Fc_Q19 < 32768 );
    334 
    335    r_Q28 = SILK_FIX_CONST( 1.0, 28 ) - silk_MUL( SILK_FIX_CONST( 0.92, 9 ), Fc_Q19 );
    336 
    337    /* b = r * [ 1; -2; 1 ]; */
    338    /* a = [ 1; -2 * r * ( 1 - 0.5 * Fc^2 ); r^2 ]; */
    339    B_Q28[ 0 ] = r_Q28;
    340    B_Q28[ 1 ] = silk_LSHIFT( -r_Q28, 1 );
    341    B_Q28[ 2 ] = r_Q28;
    342 
    343    /* -r * ( 2 - Fc * Fc ); */
    344    r_Q22  = silk_RSHIFT( r_Q28, 6 );
    345    A_Q28[ 0 ] = silk_SMULWW( r_Q22, silk_SMULWW( Fc_Q19, Fc_Q19 ) - SILK_FIX_CONST( 2.0,  22 ) );
    346    A_Q28[ 1 ] = silk_SMULWW( r_Q22, r_Q22 );
    347 
    348 #ifdef FIXED_POINT
    349    silk_biquad_alt( in, B_Q28, A_Q28, hp_mem, out, len, channels );
    350    if( channels == 2 ) {
    351        silk_biquad_alt( in+1, B_Q28, A_Q28, hp_mem+2, out+1, len, channels );
    352    }
    353 #else
    354    silk_biquad_float( in, B_Q28, A_Q28, hp_mem, out, len, channels );
    355    if( channels == 2 ) {
    356        silk_biquad_float( in+1, B_Q28, A_Q28, hp_mem+2, out+1, len, channels );
    357    }
    358 #endif
    359 }
    360 
    361 #ifdef FIXED_POINT
    362 static void dc_reject(const opus_val16 *in, opus_int32 cutoff_Hz, opus_val16 *out, opus_val32 *hp_mem, int len, int channels, opus_int32 Fs)
    363 {
    364    int c, i;
    365    int shift;
    366 
    367    /* Approximates -round(log2(4.*cutoff_Hz/Fs)) */
    368    shift=celt_ilog2(Fs/(cutoff_Hz*3));
    369    for (c=0;c<channels;c++)
    370    {
    371       for (i=0;i<len;i++)
    372       {
    373          opus_val32 x, tmp, y;
    374          x = SHL32(EXTEND32(in[channels*i+c]), 15);
    375          /* First stage */
    376          tmp = x-hp_mem[2*c];
    377          hp_mem[2*c] = hp_mem[2*c] + PSHR32(x - hp_mem[2*c], shift);
    378          /* Second stage */
    379          y = tmp - hp_mem[2*c+1];
    380          hp_mem[2*c+1] = hp_mem[2*c+1] + PSHR32(tmp - hp_mem[2*c+1], shift);
    381          out[channels*i+c] = EXTRACT16(SATURATE(PSHR32(y, 15), 32767));
    382       }
    383    }
    384 }
    385 
    386 #else
    387 static void dc_reject(const opus_val16 *in, opus_int32 cutoff_Hz, opus_val16 *out, opus_val32 *hp_mem, int len, int channels, opus_int32 Fs)
    388 {
    389    int c, i;
    390    float coef;
    391 
    392    coef = 4.0f*cutoff_Hz/Fs;
    393    for (c=0;c<channels;c++)
    394    {
    395       for (i=0;i<len;i++)
    396       {
    397          opus_val32 x, tmp, y;
    398          x = in[channels*i+c];
    399          /* First stage */
    400          tmp = x-hp_mem[2*c];
    401          hp_mem[2*c] = hp_mem[2*c] + coef*(x - hp_mem[2*c]) + VERY_SMALL;
    402          /* Second stage */
    403          y = tmp - hp_mem[2*c+1];
    404          hp_mem[2*c+1] = hp_mem[2*c+1] + coef*(tmp - hp_mem[2*c+1]) + VERY_SMALL;
    405          out[channels*i+c] = y;
    406       }
    407    }
    408 }
    409 #endif
    410 
    411 static void stereo_fade(const opus_val16 *in, opus_val16 *out, opus_val16 g1, opus_val16 g2,
    412         int overlap48, int frame_size, int channels, const opus_val16 *window, opus_int32 Fs)
    413 {
    414     int i;
    415     int overlap;
    416     int inc;
    417     inc = 48000/Fs;
    418     overlap=overlap48/inc;
    419     g1 = Q15ONE-g1;
    420     g2 = Q15ONE-g2;
    421     for (i=0;i<overlap;i++)
    422     {
    423        opus_val32 diff;
    424        opus_val16 g, w;
    425        w = MULT16_16_Q15(window[i*inc], window[i*inc]);
    426        g = SHR32(MAC16_16(MULT16_16(w,g2),
    427              Q15ONE-w, g1), 15);
    428        diff = EXTRACT16(HALF32((opus_val32)in[i*channels] - (opus_val32)in[i*channels+1]));
    429        diff = MULT16_16_Q15(g, diff);
    430        out[i*channels] = out[i*channels] - diff;
    431        out[i*channels+1] = out[i*channels+1] + diff;
    432     }
    433     for (;i<frame_size;i++)
    434     {
    435        opus_val32 diff;
    436        diff = EXTRACT16(HALF32((opus_val32)in[i*channels] - (opus_val32)in[i*channels+1]));
    437        diff = MULT16_16_Q15(g2, diff);
    438        out[i*channels] = out[i*channels] - diff;
    439        out[i*channels+1] = out[i*channels+1] + diff;
    440     }
    441 }
    442 
    443 static void gain_fade(const opus_val16 *in, opus_val16 *out, opus_val16 g1, opus_val16 g2,
    444         int overlap48, int frame_size, int channels, const opus_val16 *window, opus_int32 Fs)
    445 {
    446     int i;
    447     int inc;
    448     int overlap;
    449     int c;
    450     inc = 48000/Fs;
    451     overlap=overlap48/inc;
    452     if (channels==1)
    453     {
    454        for (i=0;i<overlap;i++)
    455        {
    456           opus_val16 g, w;
    457           w = MULT16_16_Q15(window[i*inc], window[i*inc]);
    458           g = SHR32(MAC16_16(MULT16_16(w,g2),
    459                 Q15ONE-w, g1), 15);
    460           out[i] = MULT16_16_Q15(g, in[i]);
    461        }
    462     } else {
    463        for (i=0;i<overlap;i++)
    464        {
    465           opus_val16 g, w;
    466           w = MULT16_16_Q15(window[i*inc], window[i*inc]);
    467           g = SHR32(MAC16_16(MULT16_16(w,g2),
    468                 Q15ONE-w, g1), 15);
    469           out[i*2] = MULT16_16_Q15(g, in[i*2]);
    470           out[i*2+1] = MULT16_16_Q15(g, in[i*2+1]);
    471        }
    472     }
    473     c=0;do {
    474        for (i=overlap;i<frame_size;i++)
    475        {
    476           out[i*channels+c] = MULT16_16_Q15(g2, in[i*channels+c]);
    477        }
    478     }
    479     while (++c<channels);
    480 }
    481 
    482 OpusEncoder *opus_encoder_create(opus_int32 Fs, int channels, int application, int *error)
    483 {
    484    int ret;
    485    OpusEncoder *st;
    486    if((Fs!=48000&&Fs!=24000&&Fs!=16000&&Fs!=12000&&Fs!=8000)||(channels!=1&&channels!=2)||
    487        (application != OPUS_APPLICATION_VOIP && application != OPUS_APPLICATION_AUDIO
    488        && application != OPUS_APPLICATION_RESTRICTED_LOWDELAY))
    489    {
    490       if (error)
    491          *error = OPUS_BAD_ARG;
    492       return NULL;
    493    }
    494    st = (OpusEncoder *)opus_alloc(opus_encoder_get_size(channels));
    495    if (st == NULL)
    496    {
    497       if (error)
    498          *error = OPUS_ALLOC_FAIL;
    499       return NULL;
    500    }
    501    ret = opus_encoder_init(st, Fs, channels, application);
    502    if (error)
    503       *error = ret;
    504    if (ret != OPUS_OK)
    505    {
    506       opus_free(st);
    507       st = NULL;
    508    }
    509    return st;
    510 }
    511 
    512 static opus_int32 user_bitrate_to_bitrate(OpusEncoder *st, int frame_size, int max_data_bytes)
    513 {
    514   if(!frame_size)frame_size=st->Fs/400;
    515   if (st->user_bitrate_bps==OPUS_AUTO)
    516     return 60*st->Fs/frame_size + st->Fs*st->channels;
    517   else if (st->user_bitrate_bps==OPUS_BITRATE_MAX)
    518     return max_data_bytes*8*st->Fs/frame_size;
    519   else
    520     return st->user_bitrate_bps;
    521 }
    522 
    523 #ifndef DISABLE_FLOAT_API
    524 /* Don't use more than 60 ms for the frame size analysis */
    525 #define MAX_DYNAMIC_FRAMESIZE 24
    526 /* Estimates how much the bitrate will be boosted based on the sub-frame energy */
    527 static float transient_boost(const float *E, const float *E_1, int LM, int maxM)
    528 {
    529    int i;
    530    int M;
    531    float sumE=0, sumE_1=0;
    532    float metric;
    533 
    534    M = IMIN(maxM, (1<<LM)+1);
    535    for (i=0;i<M;i++)
    536    {
    537       sumE += E[i];
    538       sumE_1 += E_1[i];
    539    }
    540    metric = sumE*sumE_1/(M*M);
    541    /*if (LM==3)
    542       printf("%f\n", metric);*/
    543    /*return metric>10 ? 1 : 0;*/
    544    /*return MAX16(0,1-exp(-.25*(metric-2.)));*/
    545    return MIN16(1,(float)sqrt(MAX16(0,.05f*(metric-2))));
    546 }
    547 
    548 /* Viterbi decoding trying to find the best frame size combination using look-ahead
    549 
    550    State numbering:
    551     0: unused
    552     1:  2.5 ms
    553     2:  5 ms (#1)
    554     3:  5 ms (#2)
    555     4: 10 ms (#1)
    556     5: 10 ms (#2)
    557     6: 10 ms (#3)
    558     7: 10 ms (#4)
    559     8: 20 ms (#1)
    560     9: 20 ms (#2)
    561    10: 20 ms (#3)
    562    11: 20 ms (#4)
    563    12: 20 ms (#5)
    564    13: 20 ms (#6)
    565    14: 20 ms (#7)
    566    15: 20 ms (#8)
    567 */
    568 static int transient_viterbi(const float *E, const float *E_1, int N, int frame_cost, int rate)
    569 {
    570    int i;
    571    float cost[MAX_DYNAMIC_FRAMESIZE][16];
    572    int states[MAX_DYNAMIC_FRAMESIZE][16];
    573    float best_cost;
    574    int best_state;
    575    float factor;
    576    /* Take into account that we damp VBR in the 32 kb/s to 64 kb/s range. */
    577    if (rate<80)
    578       factor=0;
    579    else if (rate>160)
    580       factor=1;
    581    else
    582       factor = (rate-80.f)/80.f;
    583    /* Makes variable framesize less aggressive at lower bitrates, but I can't
    584       find any valid theoretical justification for this (other than it seems
    585       to help) */
    586    for (i=0;i<16;i++)
    587    {
    588       /* Impossible state */
    589       states[0][i] = -1;
    590       cost[0][i] = 1e10;
    591    }
    592    for (i=0;i<4;i++)
    593    {
    594       cost[0][1<<i] = (frame_cost + rate*(1<<i))*(1+factor*transient_boost(E, E_1, i, N+1));
    595       states[0][1<<i] = i;
    596    }
    597    for (i=1;i<N;i++)
    598    {
    599       int j;
    600 
    601       /* Follow continuations */
    602       for (j=2;j<16;j++)
    603       {
    604          cost[i][j] = cost[i-1][j-1];
    605          states[i][j] = j-1;
    606       }
    607 
    608       /* New frames */
    609       for(j=0;j<4;j++)
    610       {
    611          int k;
    612          float min_cost;
    613          float curr_cost;
    614          states[i][1<<j] = 1;
    615          min_cost = cost[i-1][1];
    616          for(k=1;k<4;k++)
    617          {
    618             float tmp = cost[i-1][(1<<(k+1))-1];
    619             if (tmp < min_cost)
    620             {
    621                states[i][1<<j] = (1<<(k+1))-1;
    622                min_cost = tmp;
    623             }
    624          }
    625          curr_cost = (frame_cost + rate*(1<<j))*(1+factor*transient_boost(E+i, E_1+i, j, N-i+1));
    626          cost[i][1<<j] = min_cost;
    627          /* If part of the frame is outside the analysis window, only count part of the cost */
    628          if (N-i < (1<<j))
    629             cost[i][1<<j] += curr_cost*(float)(N-i)/(1<<j);
    630          else
    631             cost[i][1<<j] += curr_cost;
    632       }
    633    }
    634 
    635    best_state=1;
    636    best_cost = cost[N-1][1];
    637    /* Find best end state (doesn't force a frame to end at N-1) */
    638    for (i=2;i<16;i++)
    639    {
    640       if (cost[N-1][i]<best_cost)
    641       {
    642          best_cost = cost[N-1][i];
    643          best_state = i;
    644       }
    645    }
    646 
    647    /* Follow transitions back */
    648    for (i=N-1;i>=0;i--)
    649    {
    650       /*printf("%d ", best_state);*/
    651       best_state = states[i][best_state];
    652    }
    653    /*printf("%d\n", best_state);*/
    654    return best_state;
    655 }
    656 
    657 static int optimize_framesize(const void *x, int len, int C, opus_int32 Fs,
    658                 int bitrate, opus_val16 tonality, float *mem, int buffering,
    659                 downmix_func downmix)
    660 {
    661    int N;
    662    int i;
    663    float e[MAX_DYNAMIC_FRAMESIZE+4];
    664    float e_1[MAX_DYNAMIC_FRAMESIZE+3];
    665    opus_val32 memx;
    666    int bestLM=0;
    667    int subframe;
    668    int pos;
    669    int offset;
    670    VARDECL(opus_val32, sub);
    671 
    672    subframe = Fs/400;
    673    ALLOC(sub, subframe, opus_val32);
    674    e[0]=mem[0];
    675    e_1[0]=1.f/(EPSILON+mem[0]);
    676    if (buffering)
    677    {
    678       /* Consider the CELT delay when not in restricted-lowdelay */
    679       /* We assume the buffering is between 2.5 and 5 ms */
    680       offset = 2*subframe - buffering;
    681       celt_assert(offset>=0 && offset <= subframe);
    682       len -= offset;
    683       e[1]=mem[1];
    684       e_1[1]=1.f/(EPSILON+mem[1]);
    685       e[2]=mem[2];
    686       e_1[2]=1.f/(EPSILON+mem[2]);
    687       pos = 3;
    688    } else {
    689       pos=1;
    690       offset=0;
    691    }
    692    N=IMIN(len/subframe, MAX_DYNAMIC_FRAMESIZE);
    693    /* Just silencing a warning, it's really initialized later */
    694    memx = 0;
    695    for (i=0;i<N;i++)
    696    {
    697       float tmp;
    698       opus_val32 tmpx;
    699       int j;
    700       tmp=EPSILON;
    701 
    702       downmix(x, sub, subframe, i*subframe+offset, 0, -2, C);
    703       if (i==0)
    704          memx = sub[0];
    705       for (j=0;j<subframe;j++)
    706       {
    707          tmpx = sub[j];
    708          tmp += (tmpx-memx)*(float)(tmpx-memx);
    709          memx = tmpx;
    710       }
    711       e[i+pos] = tmp;
    712       e_1[i+pos] = 1.f/tmp;
    713    }
    714    /* Hack to get 20 ms working with APPLICATION_AUDIO
    715       The real problem is that the corresponding memory needs to use 1.5 ms
    716       from this frame and 1 ms from the next frame */
    717    e[i+pos] = e[i+pos-1];
    718    if (buffering)
    719       N=IMIN(MAX_DYNAMIC_FRAMESIZE, N+2);
    720    bestLM = transient_viterbi(e, e_1, N, (int)((1.f+.5f*tonality)*(60*C+40)), bitrate/400);
    721    mem[0] = e[1<<bestLM];
    722    if (buffering)
    723    {
    724       mem[1] = e[(1<<bestLM)+1];
    725       mem[2] = e[(1<<bestLM)+2];
    726    }
    727    return bestLM;
    728 }
    729 
    730 #endif
    731 
    732 #ifndef DISABLE_FLOAT_API
    733 #ifdef FIXED_POINT
    734 #define PCM2VAL(x) FLOAT2INT16(x)
    735 #else
    736 #define PCM2VAL(x) SCALEIN(x)
    737 #endif
    738 void downmix_float(const void *_x, opus_val32 *sub, int subframe, int offset, int c1, int c2, int C)
    739 {
    740    const float *x;
    741    opus_val32 scale;
    742    int j;
    743    x = (const float *)_x;
    744    for (j=0;j<subframe;j++)
    745       sub[j] = PCM2VAL(x[(j+offset)*C+c1]);
    746    if (c2>-1)
    747    {
    748       for (j=0;j<subframe;j++)
    749          sub[j] += PCM2VAL(x[(j+offset)*C+c2]);
    750    } else if (c2==-2)
    751    {
    752       int c;
    753       for (c=1;c<C;c++)
    754       {
    755          for (j=0;j<subframe;j++)
    756             sub[j] += PCM2VAL(x[(j+offset)*C+c]);
    757       }
    758    }
    759 #ifdef FIXED_POINT
    760    scale = (1<<SIG_SHIFT);
    761 #else
    762    scale = 1.f;
    763 #endif
    764    if (C==-2)
    765       scale /= C;
    766    else
    767       scale /= 2;
    768    for (j=0;j<subframe;j++)
    769       sub[j] *= scale;
    770 }
    771 #endif
    772 
    773 void downmix_int(const void *_x, opus_val32 *sub, int subframe, int offset, int c1, int c2, int C)
    774 {
    775    const opus_int16 *x;
    776    opus_val32 scale;
    777    int j;
    778    x = (const opus_int16 *)_x;
    779    for (j=0;j<subframe;j++)
    780       sub[j] = x[(j+offset)*C+c1];
    781    if (c2>-1)
    782    {
    783       for (j=0;j<subframe;j++)
    784          sub[j] += x[(j+offset)*C+c2];
    785    } else if (c2==-2)
    786    {
    787       int c;
    788       for (c=1;c<C;c++)
    789       {
    790          for (j=0;j<subframe;j++)
    791             sub[j] += x[(j+offset)*C+c];
    792       }
    793    }
    794 #ifdef FIXED_POINT
    795    scale = (1<<SIG_SHIFT);
    796 #else
    797    scale = 1.f/32768;
    798 #endif
    799    if (C==-2)
    800       scale /= C;
    801    else
    802       scale /= 2;
    803    for (j=0;j<subframe;j++)
    804       sub[j] *= scale;
    805 }
    806 
    807 opus_int32 frame_size_select(opus_int32 frame_size, int variable_duration, opus_int32 Fs)
    808 {
    809    int new_size;
    810    if (frame_size<Fs/400)
    811       return -1;
    812    if (variable_duration == OPUS_FRAMESIZE_ARG)
    813       new_size = frame_size;
    814    else if (variable_duration == OPUS_FRAMESIZE_VARIABLE)
    815       new_size = Fs/50;
    816    else if (variable_duration >= OPUS_FRAMESIZE_2_5_MS && variable_duration <= OPUS_FRAMESIZE_60_MS)
    817       new_size = IMIN(3*Fs/50, (Fs/400)<<(variable_duration-OPUS_FRAMESIZE_2_5_MS));
    818    else
    819       return -1;
    820    if (new_size>frame_size)
    821       return -1;
    822    if (400*new_size!=Fs && 200*new_size!=Fs && 100*new_size!=Fs &&
    823             50*new_size!=Fs && 25*new_size!=Fs && 50*new_size!=3*Fs)
    824       return -1;
    825    return new_size;
    826 }
    827 
    828 opus_int32 compute_frame_size(const void *analysis_pcm, int frame_size,
    829       int variable_duration, int C, opus_int32 Fs, int bitrate_bps,
    830       int delay_compensation, downmix_func downmix
    831 #ifndef DISABLE_FLOAT_API
    832       , float *subframe_mem
    833 #endif
    834       )
    835 {
    836 #ifndef DISABLE_FLOAT_API
    837    if (variable_duration == OPUS_FRAMESIZE_VARIABLE && frame_size >= Fs/200)
    838    {
    839       int LM = 3;
    840       LM = optimize_framesize(analysis_pcm, frame_size, C, Fs, bitrate_bps,
    841             0, subframe_mem, delay_compensation, downmix);
    842       while ((Fs/400<<LM)>frame_size)
    843          LM--;
    844       frame_size = (Fs/400<<LM);
    845    } else
    846 #else
    847    (void)analysis_pcm;
    848    (void)C;
    849    (void)bitrate_bps;
    850    (void)delay_compensation;
    851    (void)downmix;
    852 #endif
    853    {
    854       frame_size = frame_size_select(frame_size, variable_duration, Fs);
    855    }
    856    if (frame_size<0)
    857       return -1;
    858    return frame_size;
    859 }
    860 
    861 opus_val16 compute_stereo_width(const opus_val16 *pcm, int frame_size, opus_int32 Fs, StereoWidthState *mem)
    862 {
    863    opus_val32 xx, xy, yy;
    864    opus_val16 sqrt_xx, sqrt_yy;
    865    opus_val16 qrrt_xx, qrrt_yy;
    866    int frame_rate;
    867    int i;
    868    opus_val16 short_alpha;
    869 
    870    frame_rate = Fs/frame_size;
    871    short_alpha = Q15ONE - MULT16_16(25, Q15ONE)/IMAX(50,frame_rate);
    872    xx=xy=yy=0;
    873    /* Unroll by 4. The frame size is always a multiple of 4 *except* for
    874       2.5 ms frames at 12 kHz. Since this setting is very rare (and very
    875       stupid), we just discard the last two samples. */
    876    for (i=0;i<frame_size-3;i+=4)
    877    {
    878       opus_val32 pxx=0;
    879       opus_val32 pxy=0;
    880       opus_val32 pyy=0;
    881       opus_val16 x, y;
    882       x = pcm[2*i];
    883       y = pcm[2*i+1];
    884       pxx = SHR32(MULT16_16(x,x),2);
    885       pxy = SHR32(MULT16_16(x,y),2);
    886       pyy = SHR32(MULT16_16(y,y),2);
    887       x = pcm[2*i+2];
    888       y = pcm[2*i+3];
    889       pxx += SHR32(MULT16_16(x,x),2);
    890       pxy += SHR32(MULT16_16(x,y),2);
    891       pyy += SHR32(MULT16_16(y,y),2);
    892       x = pcm[2*i+4];
    893       y = pcm[2*i+5];
    894       pxx += SHR32(MULT16_16(x,x),2);
    895       pxy += SHR32(MULT16_16(x,y),2);
    896       pyy += SHR32(MULT16_16(y,y),2);
    897       x = pcm[2*i+6];
    898       y = pcm[2*i+7];
    899       pxx += SHR32(MULT16_16(x,x),2);
    900       pxy += SHR32(MULT16_16(x,y),2);
    901       pyy += SHR32(MULT16_16(y,y),2);
    902 
    903       xx += SHR32(pxx, 10);
    904       xy += SHR32(pxy, 10);
    905       yy += SHR32(pyy, 10);
    906    }
    907    mem->XX += MULT16_32_Q15(short_alpha, xx-mem->XX);
    908    mem->XY += MULT16_32_Q15(short_alpha, xy-mem->XY);
    909    mem->YY += MULT16_32_Q15(short_alpha, yy-mem->YY);
    910    mem->XX = MAX32(0, mem->XX);
    911    mem->XY = MAX32(0, mem->XY);
    912    mem->YY = MAX32(0, mem->YY);
    913    if (MAX32(mem->XX, mem->YY)>QCONST16(8e-4f, 18))
    914    {
    915       opus_val16 corr;
    916       opus_val16 ldiff;
    917       opus_val16 width;
    918       sqrt_xx = celt_sqrt(mem->XX);
    919       sqrt_yy = celt_sqrt(mem->YY);
    920       qrrt_xx = celt_sqrt(sqrt_xx);
    921       qrrt_yy = celt_sqrt(sqrt_yy);
    922       /* Inter-channel correlation */
    923       mem->XY = MIN32(mem->XY, sqrt_xx*sqrt_yy);
    924       corr = SHR32(frac_div32(mem->XY,EPSILON+MULT16_16(sqrt_xx,sqrt_yy)),16);
    925       /* Approximate loudness difference */
    926       ldiff = MULT16_16(Q15ONE, ABS16(qrrt_xx-qrrt_yy))/(EPSILON+qrrt_xx+qrrt_yy);
    927       width = MULT16_16_Q15(celt_sqrt(QCONST32(1.f,30)-MULT16_16(corr,corr)), ldiff);
    928       /* Smoothing over one second */
    929       mem->smoothed_width += (width-mem->smoothed_width)/frame_rate;
    930       /* Peak follower */
    931       mem->max_follower = MAX16(mem->max_follower-QCONST16(.02f,15)/frame_rate, mem->smoothed_width);
    932    }
    933    /*printf("%f %f %f %f %f ", corr/(float)Q15ONE, ldiff/(float)Q15ONE, width/(float)Q15ONE, mem->smoothed_width/(float)Q15ONE, mem->max_follower/(float)Q15ONE);*/
    934    return EXTRACT16(MIN32(Q15ONE, MULT16_16(20, mem->max_follower)));
    935 }
    936 
    937 opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_size,
    938                 unsigned char *data, opus_int32 out_data_bytes, int lsb_depth,
    939                 const void *analysis_pcm, opus_int32 analysis_size, int c1, int c2,
    940                 int analysis_channels, downmix_func downmix, int float_api)
    941 {
    942     void *silk_enc;
    943     CELTEncoder *celt_enc;
    944     int i;
    945     int ret=0;
    946     opus_int32 nBytes;
    947     ec_enc enc;
    948     int bytes_target;
    949     int prefill=0;
    950     int start_band = 0;
    951     int redundancy = 0;
    952     int redundancy_bytes = 0; /* Number of bytes to use for redundancy frame */
    953     int celt_to_silk = 0;
    954     VARDECL(opus_val16, pcm_buf);
    955     int nb_compr_bytes;
    956     int to_celt = 0;
    957     opus_uint32 redundant_rng = 0;
    958     int cutoff_Hz, hp_freq_smth1;
    959     int voice_est; /* Probability of voice in Q7 */
    960     opus_int32 equiv_rate;
    961     int delay_compensation;
    962     int frame_rate;
    963     opus_int32 max_rate; /* Max bitrate we're allowed to use */
    964     int curr_bandwidth;
    965     opus_val16 HB_gain;
    966     opus_int32 max_data_bytes; /* Max number of bytes we're allowed to use */
    967     int total_buffer;
    968     opus_val16 stereo_width;
    969     const CELTMode *celt_mode;
    970 #ifndef DISABLE_FLOAT_API
    971     AnalysisInfo analysis_info;
    972     int analysis_read_pos_bak=-1;
    973     int analysis_read_subframe_bak=-1;
    974 #endif
    975     VARDECL(opus_val16, tmp_prefill);
    976 
    977     ALLOC_STACK;
    978 
    979     max_data_bytes = IMIN(1276, out_data_bytes);
    980 
    981     st->rangeFinal = 0;
    982     if ((!st->variable_duration && 400*frame_size != st->Fs && 200*frame_size != st->Fs && 100*frame_size != st->Fs &&
    983          50*frame_size != st->Fs &&  25*frame_size != st->Fs &&  50*frame_size != 3*st->Fs)
    984          || (400*frame_size < st->Fs)
    985          || max_data_bytes<=0
    986          )
    987     {
    988        RESTORE_STACK;
    989        return OPUS_BAD_ARG;
    990     }
    991     silk_enc = (char*)st+st->silk_enc_offset;
    992     celt_enc = (CELTEncoder*)((char*)st+st->celt_enc_offset);
    993     if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
    994        delay_compensation = 0;
    995     else
    996        delay_compensation = st->delay_compensation;
    997 
    998     lsb_depth = IMIN(lsb_depth, st->lsb_depth);
    999 
   1000     celt_encoder_ctl(celt_enc, CELT_GET_MODE(&celt_mode));
   1001 #ifndef DISABLE_FLOAT_API
   1002     analysis_info.valid = 0;
   1003 #ifdef FIXED_POINT
   1004     if (st->silk_mode.complexity >= 10 && st->Fs==48000)
   1005 #else
   1006     if (st->silk_mode.complexity >= 7 && st->Fs==48000)
   1007 #endif
   1008     {
   1009        analysis_read_pos_bak = st->analysis.read_pos;
   1010        analysis_read_subframe_bak = st->analysis.read_subframe;
   1011        run_analysis(&st->analysis, celt_mode, analysis_pcm, analysis_size, frame_size,
   1012              c1, c2, analysis_channels, st->Fs,
   1013              lsb_depth, downmix, &analysis_info);
   1014     }
   1015 #else
   1016     (void)analysis_pcm;
   1017     (void)analysis_size;
   1018 #endif
   1019 
   1020     st->voice_ratio = -1;
   1021 
   1022 #ifndef DISABLE_FLOAT_API
   1023     st->detected_bandwidth = 0;
   1024     if (analysis_info.valid)
   1025     {
   1026        int analysis_bandwidth;
   1027        if (st->signal_type == OPUS_AUTO)
   1028           st->voice_ratio = (int)floor(.5+100*(1-analysis_info.music_prob));
   1029 
   1030        analysis_bandwidth = analysis_info.bandwidth;
   1031        if (analysis_bandwidth<=12)
   1032           st->detected_bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   1033        else if (analysis_bandwidth<=14)
   1034           st->detected_bandwidth = OPUS_BANDWIDTH_MEDIUMBAND;
   1035        else if (analysis_bandwidth<=16)
   1036           st->detected_bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1037        else if (analysis_bandwidth<=18)
   1038           st->detected_bandwidth = OPUS_BANDWIDTH_SUPERWIDEBAND;
   1039        else
   1040           st->detected_bandwidth = OPUS_BANDWIDTH_FULLBAND;
   1041     }
   1042 #endif
   1043 
   1044     if (st->channels==2 && st->force_channels!=1)
   1045        stereo_width = compute_stereo_width(pcm, frame_size, st->Fs, &st->width_mem);
   1046     else
   1047        stereo_width = 0;
   1048     total_buffer = delay_compensation;
   1049     st->bitrate_bps = user_bitrate_to_bitrate(st, frame_size, max_data_bytes);
   1050 
   1051     frame_rate = st->Fs/frame_size;
   1052     if (!st->use_vbr)
   1053     {
   1054        int cbrBytes;
   1055        /* Multiply by 3 to make sure the division is exact. */
   1056        int frame_rate3 = 3*st->Fs/frame_size;
   1057        /* We need to make sure that "int" values always fit in 16 bits. */
   1058        cbrBytes = IMIN( (3*st->bitrate_bps/8 + frame_rate3/2)/frame_rate3, max_data_bytes);
   1059        st->bitrate_bps = cbrBytes*(opus_int32)frame_rate3*8/3;
   1060        max_data_bytes = cbrBytes;
   1061     }
   1062     if (max_data_bytes<3 || st->bitrate_bps < 3*frame_rate*8
   1063        || (frame_rate<50 && (max_data_bytes*frame_rate<300 || st->bitrate_bps < 2400)))
   1064     {
   1065        /*If the space is too low to do something useful, emit 'PLC' frames.*/
   1066        int tocmode = st->mode;
   1067        int bw = st->bandwidth == 0 ? OPUS_BANDWIDTH_NARROWBAND : st->bandwidth;
   1068        if (tocmode==0)
   1069           tocmode = MODE_SILK_ONLY;
   1070        if (frame_rate>100)
   1071           tocmode = MODE_CELT_ONLY;
   1072        if (frame_rate < 50)
   1073           tocmode = MODE_SILK_ONLY;
   1074        if(tocmode==MODE_SILK_ONLY&&bw>OPUS_BANDWIDTH_WIDEBAND)
   1075           bw=OPUS_BANDWIDTH_WIDEBAND;
   1076        else if (tocmode==MODE_CELT_ONLY&&bw==OPUS_BANDWIDTH_MEDIUMBAND)
   1077           bw=OPUS_BANDWIDTH_NARROWBAND;
   1078        else if (tocmode==MODE_HYBRID&&bw<=OPUS_BANDWIDTH_SUPERWIDEBAND)
   1079           bw=OPUS_BANDWIDTH_SUPERWIDEBAND;
   1080        data[0] = gen_toc(tocmode, frame_rate, bw, st->stream_channels);
   1081        ret = 1;
   1082        if (!st->use_vbr)
   1083        {
   1084           ret = opus_packet_pad(data, ret, max_data_bytes);
   1085           if (ret == OPUS_OK)
   1086              ret = max_data_bytes;
   1087        }
   1088        RESTORE_STACK;
   1089        return ret;
   1090     }
   1091     max_rate = frame_rate*max_data_bytes*8;
   1092 
   1093     /* Equivalent 20-ms rate for mode/channel/bandwidth decisions */
   1094     equiv_rate = st->bitrate_bps - (40*st->channels+20)*(st->Fs/frame_size - 50);
   1095 
   1096     if (st->signal_type == OPUS_SIGNAL_VOICE)
   1097        voice_est = 127;
   1098     else if (st->signal_type == OPUS_SIGNAL_MUSIC)
   1099        voice_est = 0;
   1100     else if (st->voice_ratio >= 0)
   1101     {
   1102        voice_est = st->voice_ratio*327>>8;
   1103        /* For AUDIO, never be more than 90% confident of having speech */
   1104        if (st->application == OPUS_APPLICATION_AUDIO)
   1105           voice_est = IMIN(voice_est, 115);
   1106     } else if (st->application == OPUS_APPLICATION_VOIP)
   1107        voice_est = 115;
   1108     else
   1109        voice_est = 48;
   1110 
   1111     if (st->force_channels!=OPUS_AUTO && st->channels == 2)
   1112     {
   1113         st->stream_channels = st->force_channels;
   1114     } else {
   1115 #ifdef FUZZING
   1116        /* Random mono/stereo decision */
   1117        if (st->channels == 2 && (rand()&0x1F)==0)
   1118           st->stream_channels = 3-st->stream_channels;
   1119 #else
   1120        /* Rate-dependent mono-stereo decision */
   1121        if (st->channels == 2)
   1122        {
   1123           opus_int32 stereo_threshold;
   1124           stereo_threshold = stereo_music_threshold + ((voice_est*voice_est*(stereo_voice_threshold-stereo_music_threshold))>>14);
   1125           if (st->stream_channels == 2)
   1126              stereo_threshold -= 1000;
   1127           else
   1128              stereo_threshold += 1000;
   1129           st->stream_channels = (equiv_rate > stereo_threshold) ? 2 : 1;
   1130        } else {
   1131           st->stream_channels = st->channels;
   1132        }
   1133 #endif
   1134     }
   1135     equiv_rate = st->bitrate_bps - (40*st->stream_channels+20)*(st->Fs/frame_size - 50);
   1136 
   1137     /* Mode selection depending on application and signal type */
   1138     if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   1139     {
   1140        st->mode = MODE_CELT_ONLY;
   1141     } else if (st->user_forced_mode == OPUS_AUTO)
   1142     {
   1143 #ifdef FUZZING
   1144        /* Random mode switching */
   1145        if ((rand()&0xF)==0)
   1146        {
   1147           if ((rand()&0x1)==0)
   1148              st->mode = MODE_CELT_ONLY;
   1149           else
   1150              st->mode = MODE_SILK_ONLY;
   1151        } else {
   1152           if (st->prev_mode==MODE_CELT_ONLY)
   1153              st->mode = MODE_CELT_ONLY;
   1154           else
   1155              st->mode = MODE_SILK_ONLY;
   1156        }
   1157 #else
   1158        opus_int32 mode_voice, mode_music;
   1159        opus_int32 threshold;
   1160 
   1161        /* Interpolate based on stereo width */
   1162        mode_voice = (opus_int32)(MULT16_32_Q15(Q15ONE-stereo_width,mode_thresholds[0][0])
   1163              + MULT16_32_Q15(stereo_width,mode_thresholds[1][0]));
   1164        mode_music = (opus_int32)(MULT16_32_Q15(Q15ONE-stereo_width,mode_thresholds[1][1])
   1165              + MULT16_32_Q15(stereo_width,mode_thresholds[1][1]));
   1166        /* Interpolate based on speech/music probability */
   1167        threshold = mode_music + ((voice_est*voice_est*(mode_voice-mode_music))>>14);
   1168        /* Bias towards SILK for VoIP because of some useful features */
   1169        if (st->application == OPUS_APPLICATION_VOIP)
   1170           threshold += 8000;
   1171 
   1172        /*printf("%f %d\n", stereo_width/(float)Q15ONE, threshold);*/
   1173        /* Hysteresis */
   1174        if (st->prev_mode == MODE_CELT_ONLY)
   1175            threshold -= 4000;
   1176        else if (st->prev_mode>0)
   1177            threshold += 4000;
   1178 
   1179        st->mode = (equiv_rate >= threshold) ? MODE_CELT_ONLY: MODE_SILK_ONLY;
   1180 
   1181        /* When FEC is enabled and there's enough packet loss, use SILK */
   1182        if (st->silk_mode.useInBandFEC && st->silk_mode.packetLossPercentage > (128-voice_est)>>4)
   1183           st->mode = MODE_SILK_ONLY;
   1184        /* When encoding voice and DTX is enabled, set the encoder to SILK mode (at least for now) */
   1185        if (st->silk_mode.useDTX && voice_est > 100)
   1186           st->mode = MODE_SILK_ONLY;
   1187 #endif
   1188     } else {
   1189        st->mode = st->user_forced_mode;
   1190     }
   1191 
   1192     /* Override the chosen mode to make sure we meet the requested frame size */
   1193     if (st->mode != MODE_CELT_ONLY && frame_size < st->Fs/100)
   1194        st->mode = MODE_CELT_ONLY;
   1195     if (st->lfe)
   1196        st->mode = MODE_CELT_ONLY;
   1197     /* If max_data_bytes represents less than 8 kb/s, switch to CELT-only mode */
   1198     if (max_data_bytes < (frame_rate > 50 ? 12000 : 8000)*frame_size / (st->Fs * 8))
   1199        st->mode = MODE_CELT_ONLY;
   1200 
   1201     if (st->stream_channels == 1 && st->prev_channels ==2 && st->silk_mode.toMono==0
   1202           && st->mode != MODE_CELT_ONLY && st->prev_mode != MODE_CELT_ONLY)
   1203     {
   1204        /* Delay stereo->mono transition by two frames so that SILK can do a smooth downmix */
   1205        st->silk_mode.toMono = 1;
   1206        st->stream_channels = 2;
   1207     } else {
   1208        st->silk_mode.toMono = 0;
   1209     }
   1210 
   1211     if (st->prev_mode > 0 &&
   1212         ((st->mode != MODE_CELT_ONLY && st->prev_mode == MODE_CELT_ONLY) ||
   1213     (st->mode == MODE_CELT_ONLY && st->prev_mode != MODE_CELT_ONLY)))
   1214     {
   1215         redundancy = 1;
   1216         celt_to_silk = (st->mode != MODE_CELT_ONLY);
   1217         if (!celt_to_silk)
   1218         {
   1219             /* Switch to SILK/hybrid if frame size is 10 ms or more*/
   1220             if (frame_size >= st->Fs/100)
   1221             {
   1222                 st->mode = st->prev_mode;
   1223                 to_celt = 1;
   1224             } else {
   1225                 redundancy=0;
   1226             }
   1227         }
   1228     }
   1229     /* For the first frame at a new SILK bandwidth */
   1230     if (st->silk_bw_switch)
   1231     {
   1232        redundancy = 1;
   1233        celt_to_silk = 1;
   1234        st->silk_bw_switch = 0;
   1235        prefill=1;
   1236     }
   1237 
   1238     if (redundancy)
   1239     {
   1240        /* Fair share of the max size allowed */
   1241        redundancy_bytes = IMIN(257, max_data_bytes*(opus_int32)(st->Fs/200)/(frame_size+st->Fs/200));
   1242        /* For VBR, target the actual bitrate (subject to the limit above) */
   1243        if (st->use_vbr)
   1244           redundancy_bytes = IMIN(redundancy_bytes, st->bitrate_bps/1600);
   1245     }
   1246 
   1247     if (st->mode != MODE_CELT_ONLY && st->prev_mode == MODE_CELT_ONLY)
   1248     {
   1249         silk_EncControlStruct dummy;
   1250         silk_InitEncoder( silk_enc, st->arch, &dummy);
   1251         prefill=1;
   1252     }
   1253 
   1254     /* Automatic (rate-dependent) bandwidth selection */
   1255     if (st->mode == MODE_CELT_ONLY || st->first || st->silk_mode.allowBandwidthSwitch)
   1256     {
   1257         const opus_int32 *voice_bandwidth_thresholds, *music_bandwidth_thresholds;
   1258         opus_int32 bandwidth_thresholds[8];
   1259         int bandwidth = OPUS_BANDWIDTH_FULLBAND;
   1260         opus_int32 equiv_rate2;
   1261 
   1262         equiv_rate2 = equiv_rate;
   1263         if (st->mode != MODE_CELT_ONLY)
   1264         {
   1265            /* Adjust the threshold +/- 10% depending on complexity */
   1266            equiv_rate2 = equiv_rate2 * (45+st->silk_mode.complexity)/50;
   1267            /* CBR is less efficient by ~1 kb/s */
   1268            if (!st->use_vbr)
   1269               equiv_rate2 -= 1000;
   1270         }
   1271         if (st->channels==2 && st->force_channels!=1)
   1272         {
   1273            voice_bandwidth_thresholds = stereo_voice_bandwidth_thresholds;
   1274            music_bandwidth_thresholds = stereo_music_bandwidth_thresholds;
   1275         } else {
   1276            voice_bandwidth_thresholds = mono_voice_bandwidth_thresholds;
   1277            music_bandwidth_thresholds = mono_music_bandwidth_thresholds;
   1278         }
   1279         /* Interpolate bandwidth thresholds depending on voice estimation */
   1280         for (i=0;i<8;i++)
   1281         {
   1282            bandwidth_thresholds[i] = music_bandwidth_thresholds[i]
   1283                     + ((voice_est*voice_est*(voice_bandwidth_thresholds[i]-music_bandwidth_thresholds[i]))>>14);
   1284         }
   1285         do {
   1286             int threshold, hysteresis;
   1287             threshold = bandwidth_thresholds[2*(bandwidth-OPUS_BANDWIDTH_MEDIUMBAND)];
   1288             hysteresis = bandwidth_thresholds[2*(bandwidth-OPUS_BANDWIDTH_MEDIUMBAND)+1];
   1289             if (!st->first)
   1290             {
   1291                 if (st->bandwidth >= bandwidth)
   1292                     threshold -= hysteresis;
   1293                 else
   1294                     threshold += hysteresis;
   1295             }
   1296             if (equiv_rate2 >= threshold)
   1297                 break;
   1298         } while (--bandwidth>OPUS_BANDWIDTH_NARROWBAND);
   1299         st->bandwidth = bandwidth;
   1300         /* Prevents any transition to SWB/FB until the SILK layer has fully
   1301            switched to WB mode and turned the variable LP filter off */
   1302         if (!st->first && st->mode != MODE_CELT_ONLY && !st->silk_mode.inWBmodeWithoutVariableLP && st->bandwidth > OPUS_BANDWIDTH_WIDEBAND)
   1303             st->bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1304     }
   1305 
   1306     if (st->bandwidth>st->max_bandwidth)
   1307        st->bandwidth = st->max_bandwidth;
   1308 
   1309     if (st->user_bandwidth != OPUS_AUTO)
   1310         st->bandwidth = st->user_bandwidth;
   1311 
   1312     /* This prevents us from using hybrid at unsafe CBR/max rates */
   1313     if (st->mode != MODE_CELT_ONLY && max_rate < 15000)
   1314     {
   1315        st->bandwidth = IMIN(st->bandwidth, OPUS_BANDWIDTH_WIDEBAND);
   1316     }
   1317 
   1318     /* Prevents Opus from wasting bits on frequencies that are above
   1319        the Nyquist rate of the input signal */
   1320     if (st->Fs <= 24000 && st->bandwidth > OPUS_BANDWIDTH_SUPERWIDEBAND)
   1321         st->bandwidth = OPUS_BANDWIDTH_SUPERWIDEBAND;
   1322     if (st->Fs <= 16000 && st->bandwidth > OPUS_BANDWIDTH_WIDEBAND)
   1323         st->bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1324     if (st->Fs <= 12000 && st->bandwidth > OPUS_BANDWIDTH_MEDIUMBAND)
   1325         st->bandwidth = OPUS_BANDWIDTH_MEDIUMBAND;
   1326     if (st->Fs <= 8000 && st->bandwidth > OPUS_BANDWIDTH_NARROWBAND)
   1327         st->bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   1328 #ifndef DISABLE_FLOAT_API
   1329     /* Use detected bandwidth to reduce the encoded bandwidth. */
   1330     if (st->detected_bandwidth && st->user_bandwidth == OPUS_AUTO)
   1331     {
   1332        int min_detected_bandwidth;
   1333        /* Makes bandwidth detection more conservative just in case the detector
   1334           gets it wrong when we could have coded a high bandwidth transparently.
   1335           When operating in SILK/hybrid mode, we don't go below wideband to avoid
   1336           more complicated switches that require redundancy. */
   1337        if (equiv_rate <= 18000*st->stream_channels && st->mode == MODE_CELT_ONLY)
   1338           min_detected_bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   1339        else if (equiv_rate <= 24000*st->stream_channels && st->mode == MODE_CELT_ONLY)
   1340           min_detected_bandwidth = OPUS_BANDWIDTH_MEDIUMBAND;
   1341        else if (equiv_rate <= 30000*st->stream_channels)
   1342           min_detected_bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1343        else if (equiv_rate <= 44000*st->stream_channels)
   1344           min_detected_bandwidth = OPUS_BANDWIDTH_SUPERWIDEBAND;
   1345        else
   1346           min_detected_bandwidth = OPUS_BANDWIDTH_FULLBAND;
   1347 
   1348        st->detected_bandwidth = IMAX(st->detected_bandwidth, min_detected_bandwidth);
   1349        st->bandwidth = IMIN(st->bandwidth, st->detected_bandwidth);
   1350     }
   1351 #endif
   1352     celt_encoder_ctl(celt_enc, OPUS_SET_LSB_DEPTH(lsb_depth));
   1353 
   1354     /* CELT mode doesn't support mediumband, use wideband instead */
   1355     if (st->mode == MODE_CELT_ONLY && st->bandwidth == OPUS_BANDWIDTH_MEDIUMBAND)
   1356         st->bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1357     if (st->lfe)
   1358        st->bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   1359 
   1360     /* Can't support higher than wideband for >20 ms frames */
   1361     if (frame_size > st->Fs/50 && (st->mode == MODE_CELT_ONLY || st->bandwidth > OPUS_BANDWIDTH_WIDEBAND))
   1362     {
   1363        VARDECL(unsigned char, tmp_data);
   1364        int nb_frames;
   1365        int bak_mode, bak_bandwidth, bak_channels, bak_to_mono;
   1366        VARDECL(OpusRepacketizer, rp);
   1367        opus_int32 bytes_per_frame;
   1368        opus_int32 repacketize_len;
   1369 
   1370 #ifndef DISABLE_FLOAT_API
   1371        if (analysis_read_pos_bak!= -1)
   1372        {
   1373           st->analysis.read_pos = analysis_read_pos_bak;
   1374           st->analysis.read_subframe = analysis_read_subframe_bak;
   1375        }
   1376 #endif
   1377 
   1378        nb_frames = frame_size > st->Fs/25 ? 3 : 2;
   1379        bytes_per_frame = IMIN(1276,(out_data_bytes-3)/nb_frames);
   1380 
   1381        ALLOC(tmp_data, nb_frames*bytes_per_frame, unsigned char);
   1382 
   1383        ALLOC(rp, 1, OpusRepacketizer);
   1384        opus_repacketizer_init(rp);
   1385 
   1386        bak_mode = st->user_forced_mode;
   1387        bak_bandwidth = st->user_bandwidth;
   1388        bak_channels = st->force_channels;
   1389 
   1390        st->user_forced_mode = st->mode;
   1391        st->user_bandwidth = st->bandwidth;
   1392        st->force_channels = st->stream_channels;
   1393        bak_to_mono = st->silk_mode.toMono;
   1394 
   1395        if (bak_to_mono)
   1396           st->force_channels = 1;
   1397        else
   1398           st->prev_channels = st->stream_channels;
   1399        for (i=0;i<nb_frames;i++)
   1400        {
   1401           int tmp_len;
   1402           st->silk_mode.toMono = 0;
   1403           /* When switching from SILK/Hybrid to CELT, only ask for a switch at the last frame */
   1404           if (to_celt && i==nb_frames-1)
   1405              st->user_forced_mode = MODE_CELT_ONLY;
   1406           tmp_len = opus_encode_native(st, pcm+i*(st->channels*st->Fs/50), st->Fs/50,
   1407                 tmp_data+i*bytes_per_frame, bytes_per_frame, lsb_depth,
   1408                 NULL, 0, c1, c2, analysis_channels, downmix, float_api);
   1409           if (tmp_len<0)
   1410           {
   1411              RESTORE_STACK;
   1412              return OPUS_INTERNAL_ERROR;
   1413           }
   1414           ret = opus_repacketizer_cat(rp, tmp_data+i*bytes_per_frame, tmp_len);
   1415           if (ret<0)
   1416           {
   1417              RESTORE_STACK;
   1418              return OPUS_INTERNAL_ERROR;
   1419           }
   1420        }
   1421        if (st->use_vbr)
   1422           repacketize_len = out_data_bytes;
   1423        else
   1424           repacketize_len = IMIN(3*st->bitrate_bps/(3*8*50/nb_frames), out_data_bytes);
   1425        ret = opus_repacketizer_out_range_impl(rp, 0, nb_frames, data, repacketize_len, 0, !st->use_vbr);
   1426        if (ret<0)
   1427        {
   1428           RESTORE_STACK;
   1429           return OPUS_INTERNAL_ERROR;
   1430        }
   1431        st->user_forced_mode = bak_mode;
   1432        st->user_bandwidth = bak_bandwidth;
   1433        st->force_channels = bak_channels;
   1434        st->silk_mode.toMono = bak_to_mono;
   1435        RESTORE_STACK;
   1436        return ret;
   1437     }
   1438     curr_bandwidth = st->bandwidth;
   1439 
   1440     /* Chooses the appropriate mode for speech
   1441        *NEVER* switch to/from CELT-only mode here as this will invalidate some assumptions */
   1442     if (st->mode == MODE_SILK_ONLY && curr_bandwidth > OPUS_BANDWIDTH_WIDEBAND)
   1443         st->mode = MODE_HYBRID;
   1444     if (st->mode == MODE_HYBRID && curr_bandwidth <= OPUS_BANDWIDTH_WIDEBAND)
   1445         st->mode = MODE_SILK_ONLY;
   1446 
   1447     /* printf("%d %d %d %d\n", st->bitrate_bps, st->stream_channels, st->mode, curr_bandwidth); */
   1448     bytes_target = IMIN(max_data_bytes-redundancy_bytes, st->bitrate_bps * frame_size / (st->Fs * 8)) - 1;
   1449 
   1450     data += 1;
   1451 
   1452     ec_enc_init(&enc, data, max_data_bytes-1);
   1453 
   1454     ALLOC(pcm_buf, (total_buffer+frame_size)*st->channels, opus_val16);
   1455     OPUS_COPY(pcm_buf, &st->delay_buffer[(st->encoder_buffer-total_buffer)*st->channels], total_buffer*st->channels);
   1456 
   1457     if (st->mode == MODE_CELT_ONLY)
   1458        hp_freq_smth1 = silk_LSHIFT( silk_lin2log( VARIABLE_HP_MIN_CUTOFF_HZ ), 8 );
   1459     else
   1460        hp_freq_smth1 = ((silk_encoder*)silk_enc)->state_Fxx[0].sCmn.variable_HP_smth1_Q15;
   1461 
   1462     st->variable_HP_smth2_Q15 = silk_SMLAWB( st->variable_HP_smth2_Q15,
   1463           hp_freq_smth1 - st->variable_HP_smth2_Q15, SILK_FIX_CONST( VARIABLE_HP_SMTH_COEF2, 16 ) );
   1464 
   1465     /* convert from log scale to Hertz */
   1466     cutoff_Hz = silk_log2lin( silk_RSHIFT( st->variable_HP_smth2_Q15, 8 ) );
   1467 
   1468     if (st->application == OPUS_APPLICATION_VOIP)
   1469     {
   1470        hp_cutoff(pcm, cutoff_Hz, &pcm_buf[total_buffer*st->channels], st->hp_mem, frame_size, st->channels, st->Fs);
   1471     } else {
   1472        dc_reject(pcm, 3, &pcm_buf[total_buffer*st->channels], st->hp_mem, frame_size, st->channels, st->Fs);
   1473     }
   1474 #ifndef FIXED_POINT
   1475     if (float_api)
   1476     {
   1477        opus_val32 sum;
   1478        sum = celt_inner_prod(&pcm_buf[total_buffer*st->channels], &pcm_buf[total_buffer*st->channels], frame_size*st->channels, st->arch);
   1479        /* This should filter out both NaNs and ridiculous signals that could
   1480           cause NaNs further down. */
   1481        if (!(sum < 1e9f) || celt_isnan(sum))
   1482        {
   1483           OPUS_CLEAR(&pcm_buf[total_buffer*st->channels], frame_size*st->channels);
   1484           st->hp_mem[0] = st->hp_mem[1] = st->hp_mem[2] = st->hp_mem[3] = 0;
   1485        }
   1486     }
   1487 #endif
   1488 
   1489 
   1490     /* SILK processing */
   1491     HB_gain = Q15ONE;
   1492     if (st->mode != MODE_CELT_ONLY)
   1493     {
   1494         opus_int32 total_bitRate, celt_rate;
   1495 #ifdef FIXED_POINT
   1496        const opus_int16 *pcm_silk;
   1497 #else
   1498        VARDECL(opus_int16, pcm_silk);
   1499        ALLOC(pcm_silk, st->channels*frame_size, opus_int16);
   1500 #endif
   1501 
   1502         /* Distribute bits between SILK and CELT */
   1503         total_bitRate = 8 * bytes_target * frame_rate;
   1504         if( st->mode == MODE_HYBRID ) {
   1505             int HB_gain_ref;
   1506             /* Base rate for SILK */
   1507             st->silk_mode.bitRate = st->stream_channels * ( 5000 + 1000 * ( st->Fs == 100 * frame_size ) );
   1508             if( curr_bandwidth == OPUS_BANDWIDTH_SUPERWIDEBAND ) {
   1509                 /* SILK gets 2/3 of the remaining bits */
   1510                 st->silk_mode.bitRate += ( total_bitRate - st->silk_mode.bitRate ) * 2 / 3;
   1511             } else { /* FULLBAND */
   1512                 /* SILK gets 3/5 of the remaining bits */
   1513                 st->silk_mode.bitRate += ( total_bitRate - st->silk_mode.bitRate ) * 3 / 5;
   1514             }
   1515             /* Don't let SILK use more than 80% */
   1516             if( st->silk_mode.bitRate > total_bitRate * 4/5 ) {
   1517                 st->silk_mode.bitRate = total_bitRate * 4/5;
   1518             }
   1519             if (!st->energy_masking)
   1520             {
   1521                /* Increasingly attenuate high band when it gets allocated fewer bits */
   1522                celt_rate = total_bitRate - st->silk_mode.bitRate;
   1523                HB_gain_ref = (curr_bandwidth == OPUS_BANDWIDTH_SUPERWIDEBAND) ? 3000 : 3600;
   1524                HB_gain = SHL32((opus_val32)celt_rate, 9) / SHR32((opus_val32)celt_rate + st->stream_channels * HB_gain_ref, 6);
   1525                HB_gain = HB_gain < (opus_val32)Q15ONE*6/7 ? HB_gain + Q15ONE/7 : Q15ONE;
   1526             }
   1527         } else {
   1528             /* SILK gets all bits */
   1529             st->silk_mode.bitRate = total_bitRate;
   1530         }
   1531 
   1532         /* Surround masking for SILK */
   1533         if (st->energy_masking && st->use_vbr && !st->lfe)
   1534         {
   1535            opus_val32 mask_sum=0;
   1536            opus_val16 masking_depth;
   1537            opus_int32 rate_offset;
   1538            int c;
   1539            int end = 17;
   1540            opus_int16 srate = 16000;
   1541            if (st->bandwidth == OPUS_BANDWIDTH_NARROWBAND)
   1542            {
   1543               end = 13;
   1544               srate = 8000;
   1545            } else if (st->bandwidth == OPUS_BANDWIDTH_MEDIUMBAND)
   1546            {
   1547               end = 15;
   1548               srate = 12000;
   1549            }
   1550            for (c=0;c<st->channels;c++)
   1551            {
   1552               for(i=0;i<end;i++)
   1553               {
   1554                  opus_val16 mask;
   1555                  mask = MAX16(MIN16(st->energy_masking[21*c+i],
   1556                         QCONST16(.5f, DB_SHIFT)), -QCONST16(2.0f, DB_SHIFT));
   1557                  if (mask > 0)
   1558                     mask = HALF16(mask);
   1559                  mask_sum += mask;
   1560               }
   1561            }
   1562            /* Conservative rate reduction, we cut the masking in half */
   1563            masking_depth = mask_sum / end*st->channels;
   1564            masking_depth += QCONST16(.2f, DB_SHIFT);
   1565            rate_offset = (opus_int32)PSHR32(MULT16_16(srate, masking_depth), DB_SHIFT);
   1566            rate_offset = MAX32(rate_offset, -2*st->silk_mode.bitRate/3);
   1567            /* Split the rate change between the SILK and CELT part for hybrid. */
   1568            if (st->bandwidth==OPUS_BANDWIDTH_SUPERWIDEBAND || st->bandwidth==OPUS_BANDWIDTH_FULLBAND)
   1569               st->silk_mode.bitRate += 3*rate_offset/5;
   1570            else
   1571               st->silk_mode.bitRate += rate_offset;
   1572            bytes_target += rate_offset * frame_size / (8 * st->Fs);
   1573         }
   1574 
   1575         st->silk_mode.payloadSize_ms = 1000 * frame_size / st->Fs;
   1576         st->silk_mode.nChannelsAPI = st->channels;
   1577         st->silk_mode.nChannelsInternal = st->stream_channels;
   1578         if (curr_bandwidth == OPUS_BANDWIDTH_NARROWBAND) {
   1579             st->silk_mode.desiredInternalSampleRate = 8000;
   1580         } else if (curr_bandwidth == OPUS_BANDWIDTH_MEDIUMBAND) {
   1581             st->silk_mode.desiredInternalSampleRate = 12000;
   1582         } else {
   1583             silk_assert( st->mode == MODE_HYBRID || curr_bandwidth == OPUS_BANDWIDTH_WIDEBAND );
   1584             st->silk_mode.desiredInternalSampleRate = 16000;
   1585         }
   1586         if( st->mode == MODE_HYBRID ) {
   1587             /* Don't allow bandwidth reduction at lowest bitrates in hybrid mode */
   1588             st->silk_mode.minInternalSampleRate = 16000;
   1589         } else {
   1590             st->silk_mode.minInternalSampleRate = 8000;
   1591         }
   1592 
   1593         if (st->mode == MODE_SILK_ONLY)
   1594         {
   1595            opus_int32 effective_max_rate = max_rate;
   1596            st->silk_mode.maxInternalSampleRate = 16000;
   1597            if (frame_rate > 50)
   1598               effective_max_rate = effective_max_rate*2/3;
   1599            if (effective_max_rate < 13000)
   1600            {
   1601               st->silk_mode.maxInternalSampleRate = 12000;
   1602               st->silk_mode.desiredInternalSampleRate = IMIN(12000, st->silk_mode.desiredInternalSampleRate);
   1603            }
   1604            if (effective_max_rate < 9600)
   1605            {
   1606               st->silk_mode.maxInternalSampleRate = 8000;
   1607               st->silk_mode.desiredInternalSampleRate = IMIN(8000, st->silk_mode.desiredInternalSampleRate);
   1608            }
   1609         } else {
   1610            st->silk_mode.maxInternalSampleRate = 16000;
   1611         }
   1612 
   1613         st->silk_mode.useCBR = !st->use_vbr;
   1614 
   1615         /* Call SILK encoder for the low band */
   1616         nBytes = IMIN(1275, max_data_bytes-1-redundancy_bytes);
   1617 
   1618         st->silk_mode.maxBits = nBytes*8;
   1619         /* Only allow up to 90% of the bits for hybrid mode*/
   1620         if (st->mode == MODE_HYBRID)
   1621            st->silk_mode.maxBits = (opus_int32)st->silk_mode.maxBits*9/10;
   1622         if (st->silk_mode.useCBR)
   1623         {
   1624            st->silk_mode.maxBits = (st->silk_mode.bitRate * frame_size / (st->Fs * 8))*8;
   1625            /* Reduce the initial target to make it easier to reach the CBR rate */
   1626            st->silk_mode.bitRate = IMAX(1, st->silk_mode.bitRate-2000);
   1627         }
   1628 
   1629         if (prefill)
   1630         {
   1631             opus_int32 zero=0;
   1632             int prefill_offset;
   1633             /* Use a smooth onset for the SILK prefill to avoid the encoder trying to encode
   1634                a discontinuity. The exact location is what we need to avoid leaving any "gap"
   1635                in the audio when mixing with the redundant CELT frame. Here we can afford to
   1636                overwrite st->delay_buffer because the only thing that uses it before it gets
   1637                rewritten is tmp_prefill[] and even then only the part after the ramp really
   1638                gets used (rather than sent to the encoder and discarded) */
   1639             prefill_offset = st->channels*(st->encoder_buffer-st->delay_compensation-st->Fs/400);
   1640             gain_fade(st->delay_buffer+prefill_offset, st->delay_buffer+prefill_offset,
   1641                   0, Q15ONE, celt_mode->overlap, st->Fs/400, st->channels, celt_mode->window, st->Fs);
   1642             OPUS_CLEAR(st->delay_buffer, prefill_offset);
   1643 #ifdef FIXED_POINT
   1644             pcm_silk = st->delay_buffer;
   1645 #else
   1646             for (i=0;i<st->encoder_buffer*st->channels;i++)
   1647                 pcm_silk[i] = FLOAT2INT16(st->delay_buffer[i]);
   1648 #endif
   1649             silk_Encode( silk_enc, &st->silk_mode, pcm_silk, st->encoder_buffer, NULL, &zero, 1 );
   1650         }
   1651 
   1652 #ifdef FIXED_POINT
   1653         pcm_silk = pcm_buf+total_buffer*st->channels;
   1654 #else
   1655         for (i=0;i<frame_size*st->channels;i++)
   1656             pcm_silk[i] = FLOAT2INT16(pcm_buf[total_buffer*st->channels + i]);
   1657 #endif
   1658         ret = silk_Encode( silk_enc, &st->silk_mode, pcm_silk, frame_size, &enc, &nBytes, 0 );
   1659         if( ret ) {
   1660             /*fprintf (stderr, "SILK encode error: %d\n", ret);*/
   1661             /* Handle error */
   1662            RESTORE_STACK;
   1663            return OPUS_INTERNAL_ERROR;
   1664         }
   1665         if (nBytes==0)
   1666         {
   1667            st->rangeFinal = 0;
   1668            data[-1] = gen_toc(st->mode, st->Fs/frame_size, curr_bandwidth, st->stream_channels);
   1669            RESTORE_STACK;
   1670            return 1;
   1671         }
   1672         /* Extract SILK internal bandwidth for signaling in first byte */
   1673         if( st->mode == MODE_SILK_ONLY ) {
   1674             if( st->silk_mode.internalSampleRate == 8000 ) {
   1675                curr_bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   1676             } else if( st->silk_mode.internalSampleRate == 12000 ) {
   1677                curr_bandwidth = OPUS_BANDWIDTH_MEDIUMBAND;
   1678             } else if( st->silk_mode.internalSampleRate == 16000 ) {
   1679                curr_bandwidth = OPUS_BANDWIDTH_WIDEBAND;
   1680             }
   1681         } else {
   1682             silk_assert( st->silk_mode.internalSampleRate == 16000 );
   1683         }
   1684 
   1685         st->silk_mode.opusCanSwitch = st->silk_mode.switchReady;
   1686         /* FIXME: How do we allocate the redundancy for CBR? */
   1687         if (st->silk_mode.opusCanSwitch)
   1688         {
   1689            redundancy = 1;
   1690            celt_to_silk = 0;
   1691            st->silk_bw_switch = 1;
   1692         }
   1693     }
   1694 
   1695     /* CELT processing */
   1696     {
   1697         int endband=21;
   1698 
   1699         switch(curr_bandwidth)
   1700         {
   1701             case OPUS_BANDWIDTH_NARROWBAND:
   1702                 endband = 13;
   1703                 break;
   1704             case OPUS_BANDWIDTH_MEDIUMBAND:
   1705             case OPUS_BANDWIDTH_WIDEBAND:
   1706                 endband = 17;
   1707                 break;
   1708             case OPUS_BANDWIDTH_SUPERWIDEBAND:
   1709                 endband = 19;
   1710                 break;
   1711             case OPUS_BANDWIDTH_FULLBAND:
   1712                 endband = 21;
   1713                 break;
   1714         }
   1715         celt_encoder_ctl(celt_enc, CELT_SET_END_BAND(endband));
   1716         celt_encoder_ctl(celt_enc, CELT_SET_CHANNELS(st->stream_channels));
   1717     }
   1718     celt_encoder_ctl(celt_enc, OPUS_SET_BITRATE(OPUS_BITRATE_MAX));
   1719     if (st->mode != MODE_SILK_ONLY)
   1720     {
   1721         opus_val32 celt_pred=2;
   1722         celt_encoder_ctl(celt_enc, OPUS_SET_VBR(0));
   1723         /* We may still decide to disable prediction later */
   1724         if (st->silk_mode.reducedDependency)
   1725            celt_pred = 0;
   1726         celt_encoder_ctl(celt_enc, CELT_SET_PREDICTION(celt_pred));
   1727 
   1728         if (st->mode == MODE_HYBRID)
   1729         {
   1730             int len;
   1731 
   1732             len = (ec_tell(&enc)+7)>>3;
   1733             if (redundancy)
   1734                len += st->mode == MODE_HYBRID ? 3 : 1;
   1735             if( st->use_vbr ) {
   1736                 nb_compr_bytes = len + bytes_target - (st->silk_mode.bitRate * frame_size) / (8 * st->Fs);
   1737             } else {
   1738                 /* check if SILK used up too much */
   1739                 nb_compr_bytes = len > bytes_target ? len : bytes_target;
   1740             }
   1741         } else {
   1742             if (st->use_vbr)
   1743             {
   1744                 opus_int32 bonus=0;
   1745 #ifndef DISABLE_FLOAT_API
   1746                 if (st->variable_duration==OPUS_FRAMESIZE_VARIABLE && frame_size != st->Fs/50)
   1747                 {
   1748                    bonus = (60*st->stream_channels+40)*(st->Fs/frame_size-50);
   1749                    if (analysis_info.valid)
   1750                       bonus = (opus_int32)(bonus*(1.f+.5f*analysis_info.tonality));
   1751                 }
   1752 #endif
   1753                 celt_encoder_ctl(celt_enc, OPUS_SET_VBR(1));
   1754                 celt_encoder_ctl(celt_enc, OPUS_SET_VBR_CONSTRAINT(st->vbr_constraint));
   1755                 celt_encoder_ctl(celt_enc, OPUS_SET_BITRATE(st->bitrate_bps+bonus));
   1756                 nb_compr_bytes = max_data_bytes-1-redundancy_bytes;
   1757             } else {
   1758                 nb_compr_bytes = bytes_target;
   1759             }
   1760         }
   1761 
   1762     } else {
   1763         nb_compr_bytes = 0;
   1764     }
   1765 
   1766     ALLOC(tmp_prefill, st->channels*st->Fs/400, opus_val16);
   1767     if (st->mode != MODE_SILK_ONLY && st->mode != st->prev_mode && st->prev_mode > 0)
   1768     {
   1769        OPUS_COPY(tmp_prefill, &st->delay_buffer[(st->encoder_buffer-total_buffer-st->Fs/400)*st->channels], st->channels*st->Fs/400);
   1770     }
   1771 
   1772     if (st->channels*(st->encoder_buffer-(frame_size+total_buffer)) > 0)
   1773     {
   1774        OPUS_MOVE(st->delay_buffer, &st->delay_buffer[st->channels*frame_size], st->channels*(st->encoder_buffer-frame_size-total_buffer));
   1775        OPUS_COPY(&st->delay_buffer[st->channels*(st->encoder_buffer-frame_size-total_buffer)],
   1776              &pcm_buf[0],
   1777              (frame_size+total_buffer)*st->channels);
   1778     } else {
   1779        OPUS_COPY(st->delay_buffer, &pcm_buf[(frame_size+total_buffer-st->encoder_buffer)*st->channels], st->encoder_buffer*st->channels);
   1780     }
   1781     /* gain_fade() and stereo_fade() need to be after the buffer copying
   1782        because we don't want any of this to affect the SILK part */
   1783     if( st->prev_HB_gain < Q15ONE || HB_gain < Q15ONE ) {
   1784        gain_fade(pcm_buf, pcm_buf,
   1785              st->prev_HB_gain, HB_gain, celt_mode->overlap, frame_size, st->channels, celt_mode->window, st->Fs);
   1786     }
   1787     st->prev_HB_gain = HB_gain;
   1788     if (st->mode != MODE_HYBRID || st->stream_channels==1)
   1789        st->silk_mode.stereoWidth_Q14 = IMIN((1<<14),2*IMAX(0,equiv_rate-30000));
   1790     if( !st->energy_masking && st->channels == 2 ) {
   1791         /* Apply stereo width reduction (at low bitrates) */
   1792         if( st->hybrid_stereo_width_Q14 < (1 << 14) || st->silk_mode.stereoWidth_Q14 < (1 << 14) ) {
   1793             opus_val16 g1, g2;
   1794             g1 = st->hybrid_stereo_width_Q14;
   1795             g2 = (opus_val16)(st->silk_mode.stereoWidth_Q14);
   1796 #ifdef FIXED_POINT
   1797             g1 = g1==16384 ? Q15ONE : SHL16(g1,1);
   1798             g2 = g2==16384 ? Q15ONE : SHL16(g2,1);
   1799 #else
   1800             g1 *= (1.f/16384);
   1801             g2 *= (1.f/16384);
   1802 #endif
   1803             stereo_fade(pcm_buf, pcm_buf, g1, g2, celt_mode->overlap,
   1804                   frame_size, st->channels, celt_mode->window, st->Fs);
   1805             st->hybrid_stereo_width_Q14 = st->silk_mode.stereoWidth_Q14;
   1806         }
   1807     }
   1808 
   1809     if ( st->mode != MODE_CELT_ONLY && ec_tell(&enc)+17+20*(st->mode == MODE_HYBRID) <= 8*(max_data_bytes-1))
   1810     {
   1811         /* For SILK mode, the redundancy is inferred from the length */
   1812         if (st->mode == MODE_HYBRID && (redundancy || ec_tell(&enc)+37 <= 8*nb_compr_bytes))
   1813            ec_enc_bit_logp(&enc, redundancy, 12);
   1814         if (redundancy)
   1815         {
   1816             int max_redundancy;
   1817             ec_enc_bit_logp(&enc, celt_to_silk, 1);
   1818             if (st->mode == MODE_HYBRID)
   1819                max_redundancy = (max_data_bytes-1)-nb_compr_bytes;
   1820             else
   1821                max_redundancy = (max_data_bytes-1)-((ec_tell(&enc)+7)>>3);
   1822             /* Target the same bit-rate for redundancy as for the rest,
   1823                up to a max of 257 bytes */
   1824             redundancy_bytes = IMIN(max_redundancy, st->bitrate_bps/1600);
   1825             redundancy_bytes = IMIN(257, IMAX(2, redundancy_bytes));
   1826             if (st->mode == MODE_HYBRID)
   1827                 ec_enc_uint(&enc, redundancy_bytes-2, 256);
   1828         }
   1829     } else {
   1830         redundancy = 0;
   1831     }
   1832 
   1833     if (!redundancy)
   1834     {
   1835        st->silk_bw_switch = 0;
   1836        redundancy_bytes = 0;
   1837     }
   1838     if (st->mode != MODE_CELT_ONLY)start_band=17;
   1839 
   1840     if (st->mode == MODE_SILK_ONLY)
   1841     {
   1842         ret = (ec_tell(&enc)+7)>>3;
   1843         ec_enc_done(&enc);
   1844         nb_compr_bytes = ret;
   1845     } else {
   1846        nb_compr_bytes = IMIN((max_data_bytes-1)-redundancy_bytes, nb_compr_bytes);
   1847        ec_enc_shrink(&enc, nb_compr_bytes);
   1848     }
   1849 
   1850 #ifndef DISABLE_FLOAT_API
   1851     if (redundancy || st->mode != MODE_SILK_ONLY)
   1852        celt_encoder_ctl(celt_enc, CELT_SET_ANALYSIS(&analysis_info));
   1853 #endif
   1854 
   1855     /* 5 ms redundant frame for CELT->SILK */
   1856     if (redundancy && celt_to_silk)
   1857     {
   1858         int err;
   1859         celt_encoder_ctl(celt_enc, CELT_SET_START_BAND(0));
   1860         celt_encoder_ctl(celt_enc, OPUS_SET_VBR(0));
   1861         err = celt_encode_with_ec(celt_enc, pcm_buf, st->Fs/200, data+nb_compr_bytes, redundancy_bytes, NULL);
   1862         if (err < 0)
   1863         {
   1864            RESTORE_STACK;
   1865            return OPUS_INTERNAL_ERROR;
   1866         }
   1867         celt_encoder_ctl(celt_enc, OPUS_GET_FINAL_RANGE(&redundant_rng));
   1868         celt_encoder_ctl(celt_enc, OPUS_RESET_STATE);
   1869     }
   1870 
   1871     celt_encoder_ctl(celt_enc, CELT_SET_START_BAND(start_band));
   1872 
   1873     if (st->mode != MODE_SILK_ONLY)
   1874     {
   1875         if (st->mode != st->prev_mode && st->prev_mode > 0)
   1876         {
   1877            unsigned char dummy[2];
   1878            celt_encoder_ctl(celt_enc, OPUS_RESET_STATE);
   1879 
   1880            /* Prefilling */
   1881            celt_encode_with_ec(celt_enc, tmp_prefill, st->Fs/400, dummy, 2, NULL);
   1882            celt_encoder_ctl(celt_enc, CELT_SET_PREDICTION(0));
   1883         }
   1884         /* If false, we already busted the budget and we'll end up with a "PLC packet" */
   1885         if (ec_tell(&enc) <= 8*nb_compr_bytes)
   1886         {
   1887            ret = celt_encode_with_ec(celt_enc, pcm_buf, frame_size, NULL, nb_compr_bytes, &enc);
   1888            if (ret < 0)
   1889            {
   1890               RESTORE_STACK;
   1891               return OPUS_INTERNAL_ERROR;
   1892            }
   1893         }
   1894     }
   1895 
   1896     /* 5 ms redundant frame for SILK->CELT */
   1897     if (redundancy && !celt_to_silk)
   1898     {
   1899         int err;
   1900         unsigned char dummy[2];
   1901         int N2, N4;
   1902         N2 = st->Fs/200;
   1903         N4 = st->Fs/400;
   1904 
   1905         celt_encoder_ctl(celt_enc, OPUS_RESET_STATE);
   1906         celt_encoder_ctl(celt_enc, CELT_SET_START_BAND(0));
   1907         celt_encoder_ctl(celt_enc, CELT_SET_PREDICTION(0));
   1908 
   1909         /* NOTE: We could speed this up slightly (at the expense of code size) by just adding a function that prefills the buffer */
   1910         celt_encode_with_ec(celt_enc, pcm_buf+st->channels*(frame_size-N2-N4), N4, dummy, 2, NULL);
   1911 
   1912         err = celt_encode_with_ec(celt_enc, pcm_buf+st->channels*(frame_size-N2), N2, data+nb_compr_bytes, redundancy_bytes, NULL);
   1913         if (err < 0)
   1914         {
   1915            RESTORE_STACK;
   1916            return OPUS_INTERNAL_ERROR;
   1917         }
   1918         celt_encoder_ctl(celt_enc, OPUS_GET_FINAL_RANGE(&redundant_rng));
   1919     }
   1920 
   1921 
   1922 
   1923     /* Signalling the mode in the first byte */
   1924     data--;
   1925     data[0] = gen_toc(st->mode, st->Fs/frame_size, curr_bandwidth, st->stream_channels);
   1926 
   1927     st->rangeFinal = enc.rng ^ redundant_rng;
   1928 
   1929     if (to_celt)
   1930         st->prev_mode = MODE_CELT_ONLY;
   1931     else
   1932         st->prev_mode = st->mode;
   1933     st->prev_channels = st->stream_channels;
   1934     st->prev_framesize = frame_size;
   1935 
   1936     st->first = 0;
   1937 
   1938     /* In the unlikely case that the SILK encoder busted its target, tell
   1939        the decoder to call the PLC */
   1940     if (ec_tell(&enc) > (max_data_bytes-1)*8)
   1941     {
   1942        if (max_data_bytes < 2)
   1943        {
   1944           RESTORE_STACK;
   1945           return OPUS_BUFFER_TOO_SMALL;
   1946        }
   1947        data[1] = 0;
   1948        ret = 1;
   1949        st->rangeFinal = 0;
   1950     } else if (st->mode==MODE_SILK_ONLY&&!redundancy)
   1951     {
   1952        /*When in LPC only mode it's perfectly
   1953          reasonable to strip off trailing zero bytes as
   1954          the required range decoder behavior is to
   1955          fill these in. This can't be done when the MDCT
   1956          modes are used because the decoder needs to know
   1957          the actual length for allocation purposes.*/
   1958        while(ret>2&&data[ret]==0)ret--;
   1959     }
   1960     /* Count ToC and redundancy */
   1961     ret += 1+redundancy_bytes;
   1962     if (!st->use_vbr)
   1963     {
   1964        if (opus_packet_pad(data, ret, max_data_bytes) != OPUS_OK)
   1965 
   1966        {
   1967           RESTORE_STACK;
   1968           return OPUS_INTERNAL_ERROR;
   1969        }
   1970        ret = max_data_bytes;
   1971     }
   1972     RESTORE_STACK;
   1973     return ret;
   1974 }
   1975 
   1976 #ifdef FIXED_POINT
   1977 
   1978 #ifndef DISABLE_FLOAT_API
   1979 opus_int32 opus_encode_float(OpusEncoder *st, const float *pcm, int analysis_frame_size,
   1980       unsigned char *data, opus_int32 max_data_bytes)
   1981 {
   1982    int i, ret;
   1983    int frame_size;
   1984    int delay_compensation;
   1985    VARDECL(opus_int16, in);
   1986    ALLOC_STACK;
   1987 
   1988    if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   1989       delay_compensation = 0;
   1990    else
   1991       delay_compensation = st->delay_compensation;
   1992    frame_size = compute_frame_size(pcm, analysis_frame_size,
   1993          st->variable_duration, st->channels, st->Fs, st->bitrate_bps,
   1994          delay_compensation, downmix_float, st->analysis.subframe_mem);
   1995 
   1996    ALLOC(in, frame_size*st->channels, opus_int16);
   1997 
   1998    for (i=0;i<frame_size*st->channels;i++)
   1999       in[i] = FLOAT2INT16(pcm[i]);
   2000    ret = opus_encode_native(st, in, frame_size, data, max_data_bytes, 16,
   2001                             pcm, analysis_frame_size, 0, -2, st->channels, downmix_float, 1);
   2002    RESTORE_STACK;
   2003    return ret;
   2004 }
   2005 #endif
   2006 
   2007 opus_int32 opus_encode(OpusEncoder *st, const opus_int16 *pcm, int analysis_frame_size,
   2008                 unsigned char *data, opus_int32 out_data_bytes)
   2009 {
   2010    int frame_size;
   2011    int delay_compensation;
   2012    if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   2013       delay_compensation = 0;
   2014    else
   2015       delay_compensation = st->delay_compensation;
   2016    frame_size = compute_frame_size(pcm, analysis_frame_size,
   2017          st->variable_duration, st->channels, st->Fs, st->bitrate_bps,
   2018          delay_compensation, downmix_int
   2019 #ifndef DISABLE_FLOAT_API
   2020          , st->analysis.subframe_mem
   2021 #endif
   2022          );
   2023    return opus_encode_native(st, pcm, frame_size, data, out_data_bytes, 16,
   2024                              pcm, analysis_frame_size, 0, -2, st->channels, downmix_int, 0);
   2025 }
   2026 
   2027 #else
   2028 opus_int32 opus_encode(OpusEncoder *st, const opus_int16 *pcm, int analysis_frame_size,
   2029       unsigned char *data, opus_int32 max_data_bytes)
   2030 {
   2031    int i, ret;
   2032    int frame_size;
   2033    int delay_compensation;
   2034    VARDECL(float, in);
   2035    ALLOC_STACK;
   2036 
   2037    if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   2038       delay_compensation = 0;
   2039    else
   2040       delay_compensation = st->delay_compensation;
   2041    frame_size = compute_frame_size(pcm, analysis_frame_size,
   2042          st->variable_duration, st->channels, st->Fs, st->bitrate_bps,
   2043          delay_compensation, downmix_int, st->analysis.subframe_mem);
   2044 
   2045    ALLOC(in, frame_size*st->channels, float);
   2046 
   2047    for (i=0;i<frame_size*st->channels;i++)
   2048       in[i] = (1.0f/32768)*pcm[i];
   2049    ret = opus_encode_native(st, in, frame_size, data, max_data_bytes, 16,
   2050                             pcm, analysis_frame_size, 0, -2, st->channels, downmix_int, 0);
   2051    RESTORE_STACK;
   2052    return ret;
   2053 }
   2054 opus_int32 opus_encode_float(OpusEncoder *st, const float *pcm, int analysis_frame_size,
   2055                       unsigned char *data, opus_int32 out_data_bytes)
   2056 {
   2057    int frame_size;
   2058    int delay_compensation;
   2059    if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   2060       delay_compensation = 0;
   2061    else
   2062       delay_compensation = st->delay_compensation;
   2063    frame_size = compute_frame_size(pcm, analysis_frame_size,
   2064          st->variable_duration, st->channels, st->Fs, st->bitrate_bps,
   2065          delay_compensation, downmix_float, st->analysis.subframe_mem);
   2066    return opus_encode_native(st, pcm, frame_size, data, out_data_bytes, 24,
   2067                              pcm, analysis_frame_size, 0, -2, st->channels, downmix_float, 1);
   2068 }
   2069 #endif
   2070 
   2071 
   2072 int opus_encoder_ctl(OpusEncoder *st, int request, ...)
   2073 {
   2074     int ret;
   2075     CELTEncoder *celt_enc;
   2076     va_list ap;
   2077 
   2078     ret = OPUS_OK;
   2079     va_start(ap, request);
   2080 
   2081     celt_enc = (CELTEncoder*)((char*)st+st->celt_enc_offset);
   2082 
   2083     switch (request)
   2084     {
   2085         case OPUS_SET_APPLICATION_REQUEST:
   2086         {
   2087             opus_int32 value = va_arg(ap, opus_int32);
   2088             if (   (value != OPUS_APPLICATION_VOIP && value != OPUS_APPLICATION_AUDIO
   2089                  && value != OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   2090                || (!st->first && st->application != value))
   2091             {
   2092                ret = OPUS_BAD_ARG;
   2093                break;
   2094             }
   2095             st->application = value;
   2096         }
   2097         break;
   2098         case OPUS_GET_APPLICATION_REQUEST:
   2099         {
   2100             opus_int32 *value = va_arg(ap, opus_int32*);
   2101             if (!value)
   2102             {
   2103                goto bad_arg;
   2104             }
   2105             *value = st->application;
   2106         }
   2107         break;
   2108         case OPUS_SET_BITRATE_REQUEST:
   2109         {
   2110             opus_int32 value = va_arg(ap, opus_int32);
   2111             if (value != OPUS_AUTO && value != OPUS_BITRATE_MAX)
   2112             {
   2113                 if (value <= 0)
   2114                     goto bad_arg;
   2115                 else if (value <= 500)
   2116                     value = 500;
   2117                 else if (value > (opus_int32)300000*st->channels)
   2118                     value = (opus_int32)300000*st->channels;
   2119             }
   2120             st->user_bitrate_bps = value;
   2121         }
   2122         break;
   2123         case OPUS_GET_BITRATE_REQUEST:
   2124         {
   2125             opus_int32 *value = va_arg(ap, opus_int32*);
   2126             if (!value)
   2127             {
   2128                goto bad_arg;
   2129             }
   2130             *value = user_bitrate_to_bitrate(st, st->prev_framesize, 1276);
   2131         }
   2132         break;
   2133         case OPUS_SET_FORCE_CHANNELS_REQUEST:
   2134         {
   2135             opus_int32 value = va_arg(ap, opus_int32);
   2136             if((value<1 || value>st->channels) && value != OPUS_AUTO)
   2137             {
   2138                goto bad_arg;
   2139             }
   2140             st->force_channels = value;
   2141         }
   2142         break;
   2143         case OPUS_GET_FORCE_CHANNELS_REQUEST:
   2144         {
   2145             opus_int32 *value = va_arg(ap, opus_int32*);
   2146             if (!value)
   2147             {
   2148                goto bad_arg;
   2149             }
   2150             *value = st->force_channels;
   2151         }
   2152         break;
   2153         case OPUS_SET_MAX_BANDWIDTH_REQUEST:
   2154         {
   2155             opus_int32 value = va_arg(ap, opus_int32);
   2156             if (value < OPUS_BANDWIDTH_NARROWBAND || value > OPUS_BANDWIDTH_FULLBAND)
   2157             {
   2158                goto bad_arg;
   2159             }
   2160             st->max_bandwidth = value;
   2161             if (st->max_bandwidth == OPUS_BANDWIDTH_NARROWBAND) {
   2162                 st->silk_mode.maxInternalSampleRate = 8000;
   2163             } else if (st->max_bandwidth == OPUS_BANDWIDTH_MEDIUMBAND) {
   2164                 st->silk_mode.maxInternalSampleRate = 12000;
   2165             } else {
   2166                 st->silk_mode.maxInternalSampleRate = 16000;
   2167             }
   2168         }
   2169         break;
   2170         case OPUS_GET_MAX_BANDWIDTH_REQUEST:
   2171         {
   2172             opus_int32 *value = va_arg(ap, opus_int32*);
   2173             if (!value)
   2174             {
   2175                goto bad_arg;
   2176             }
   2177             *value = st->max_bandwidth;
   2178         }
   2179         break;
   2180         case OPUS_SET_BANDWIDTH_REQUEST:
   2181         {
   2182             opus_int32 value = va_arg(ap, opus_int32);
   2183             if ((value < OPUS_BANDWIDTH_NARROWBAND || value > OPUS_BANDWIDTH_FULLBAND) && value != OPUS_AUTO)
   2184             {
   2185                goto bad_arg;
   2186             }
   2187             st->user_bandwidth = value;
   2188             if (st->user_bandwidth == OPUS_BANDWIDTH_NARROWBAND) {
   2189                 st->silk_mode.maxInternalSampleRate = 8000;
   2190             } else if (st->user_bandwidth == OPUS_BANDWIDTH_MEDIUMBAND) {
   2191                 st->silk_mode.maxInternalSampleRate = 12000;
   2192             } else {
   2193                 st->silk_mode.maxInternalSampleRate = 16000;
   2194             }
   2195         }
   2196         break;
   2197         case OPUS_GET_BANDWIDTH_REQUEST:
   2198         {
   2199             opus_int32 *value = va_arg(ap, opus_int32*);
   2200             if (!value)
   2201             {
   2202                goto bad_arg;
   2203             }
   2204             *value = st->bandwidth;
   2205         }
   2206         break;
   2207         case OPUS_SET_DTX_REQUEST:
   2208         {
   2209             opus_int32 value = va_arg(ap, opus_int32);
   2210             if(value<0 || value>1)
   2211             {
   2212                goto bad_arg;
   2213             }
   2214             st->silk_mode.useDTX = value;
   2215         }
   2216         break;
   2217         case OPUS_GET_DTX_REQUEST:
   2218         {
   2219             opus_int32 *value = va_arg(ap, opus_int32*);
   2220             if (!value)
   2221             {
   2222                goto bad_arg;
   2223             }
   2224             *value = st->silk_mode.useDTX;
   2225         }
   2226         break;
   2227         case OPUS_SET_COMPLEXITY_REQUEST:
   2228         {
   2229             opus_int32 value = va_arg(ap, opus_int32);
   2230             if(value<0 || value>10)
   2231             {
   2232                goto bad_arg;
   2233             }
   2234             st->silk_mode.complexity = value;
   2235             celt_encoder_ctl(celt_enc, OPUS_SET_COMPLEXITY(value));
   2236         }
   2237         break;
   2238         case OPUS_GET_COMPLEXITY_REQUEST:
   2239         {
   2240             opus_int32 *value = va_arg(ap, opus_int32*);
   2241             if (!value)
   2242             {
   2243                goto bad_arg;
   2244             }
   2245             *value = st->silk_mode.complexity;
   2246         }
   2247         break;
   2248         case OPUS_SET_INBAND_FEC_REQUEST:
   2249         {
   2250             opus_int32 value = va_arg(ap, opus_int32);
   2251             if(value<0 || value>1)
   2252             {
   2253                goto bad_arg;
   2254             }
   2255             st->silk_mode.useInBandFEC = value;
   2256         }
   2257         break;
   2258         case OPUS_GET_INBAND_FEC_REQUEST:
   2259         {
   2260             opus_int32 *value = va_arg(ap, opus_int32*);
   2261             if (!value)
   2262             {
   2263                goto bad_arg;
   2264             }
   2265             *value = st->silk_mode.useInBandFEC;
   2266         }
   2267         break;
   2268         case OPUS_SET_PACKET_LOSS_PERC_REQUEST:
   2269         {
   2270             opus_int32 value = va_arg(ap, opus_int32);
   2271             if (value < 0 || value > 100)
   2272             {
   2273                goto bad_arg;
   2274             }
   2275             st->silk_mode.packetLossPercentage = value;
   2276             celt_encoder_ctl(celt_enc, OPUS_SET_PACKET_LOSS_PERC(value));
   2277         }
   2278         break;
   2279         case OPUS_GET_PACKET_LOSS_PERC_REQUEST:
   2280         {
   2281             opus_int32 *value = va_arg(ap, opus_int32*);
   2282             if (!value)
   2283             {
   2284                goto bad_arg;
   2285             }
   2286             *value = st->silk_mode.packetLossPercentage;
   2287         }
   2288         break;
   2289         case OPUS_SET_VBR_REQUEST:
   2290         {
   2291             opus_int32 value = va_arg(ap, opus_int32);
   2292             if(value<0 || value>1)
   2293             {
   2294                goto bad_arg;
   2295             }
   2296             st->use_vbr = value;
   2297             st->silk_mode.useCBR = 1-value;
   2298         }
   2299         break;
   2300         case OPUS_GET_VBR_REQUEST:
   2301         {
   2302             opus_int32 *value = va_arg(ap, opus_int32*);
   2303             if (!value)
   2304             {
   2305                goto bad_arg;
   2306             }
   2307             *value = st->use_vbr;
   2308         }
   2309         break;
   2310         case OPUS_SET_VOICE_RATIO_REQUEST:
   2311         {
   2312             opus_int32 value = va_arg(ap, opus_int32);
   2313             if (value<-1 || value>100)
   2314             {
   2315                goto bad_arg;
   2316             }
   2317             st->voice_ratio = value;
   2318         }
   2319         break;
   2320         case OPUS_GET_VOICE_RATIO_REQUEST:
   2321         {
   2322             opus_int32 *value = va_arg(ap, opus_int32*);
   2323             if (!value)
   2324             {
   2325                goto bad_arg;
   2326             }
   2327             *value = st->voice_ratio;
   2328         }
   2329         break;
   2330         case OPUS_SET_VBR_CONSTRAINT_REQUEST:
   2331         {
   2332             opus_int32 value = va_arg(ap, opus_int32);
   2333             if(value<0 || value>1)
   2334             {
   2335                goto bad_arg;
   2336             }
   2337             st->vbr_constraint = value;
   2338         }
   2339         break;
   2340         case OPUS_GET_VBR_CONSTRAINT_REQUEST:
   2341         {
   2342             opus_int32 *value = va_arg(ap, opus_int32*);
   2343             if (!value)
   2344             {
   2345                goto bad_arg;
   2346             }
   2347             *value = st->vbr_constraint;
   2348         }
   2349         break;
   2350         case OPUS_SET_SIGNAL_REQUEST:
   2351         {
   2352             opus_int32 value = va_arg(ap, opus_int32);
   2353             if(value!=OPUS_AUTO && value!=OPUS_SIGNAL_VOICE && value!=OPUS_SIGNAL_MUSIC)
   2354             {
   2355                goto bad_arg;
   2356             }
   2357             st->signal_type = value;
   2358         }
   2359         break;
   2360         case OPUS_GET_SIGNAL_REQUEST:
   2361         {
   2362             opus_int32 *value = va_arg(ap, opus_int32*);
   2363             if (!value)
   2364             {
   2365                goto bad_arg;
   2366             }
   2367             *value = st->signal_type;
   2368         }
   2369         break;
   2370         case OPUS_GET_LOOKAHEAD_REQUEST:
   2371         {
   2372             opus_int32 *value = va_arg(ap, opus_int32*);
   2373             if (!value)
   2374             {
   2375                goto bad_arg;
   2376             }
   2377             *value = st->Fs/400;
   2378             if (st->application != OPUS_APPLICATION_RESTRICTED_LOWDELAY)
   2379                 *value += st->delay_compensation;
   2380         }
   2381         break;
   2382         case OPUS_GET_SAMPLE_RATE_REQUEST:
   2383         {
   2384             opus_int32 *value = va_arg(ap, opus_int32*);
   2385             if (!value)
   2386             {
   2387                goto bad_arg;
   2388             }
   2389             *value = st->Fs;
   2390         }
   2391         break;
   2392         case OPUS_GET_FINAL_RANGE_REQUEST:
   2393         {
   2394             opus_uint32 *value = va_arg(ap, opus_uint32*);
   2395             if (!value)
   2396             {
   2397                goto bad_arg;
   2398             }
   2399             *value = st->rangeFinal;
   2400         }
   2401         break;
   2402         case OPUS_SET_LSB_DEPTH_REQUEST:
   2403         {
   2404             opus_int32 value = va_arg(ap, opus_int32);
   2405             if (value<8 || value>24)
   2406             {
   2407                goto bad_arg;
   2408             }
   2409             st->lsb_depth=value;
   2410         }
   2411         break;
   2412         case OPUS_GET_LSB_DEPTH_REQUEST:
   2413         {
   2414             opus_int32 *value = va_arg(ap, opus_int32*);
   2415             if (!value)
   2416             {
   2417                goto bad_arg;
   2418             }
   2419             *value = st->lsb_depth;
   2420         }
   2421         break;
   2422         case OPUS_SET_EXPERT_FRAME_DURATION_REQUEST:
   2423         {
   2424             opus_int32 value = va_arg(ap, opus_int32);
   2425             if (value != OPUS_FRAMESIZE_ARG   && value != OPUS_FRAMESIZE_2_5_MS &&
   2426                 value != OPUS_FRAMESIZE_5_MS  && value != OPUS_FRAMESIZE_10_MS  &&
   2427                 value != OPUS_FRAMESIZE_20_MS && value != OPUS_FRAMESIZE_40_MS  &&
   2428                 value != OPUS_FRAMESIZE_60_MS && value != OPUS_FRAMESIZE_VARIABLE)
   2429             {
   2430                goto bad_arg;
   2431             }
   2432             st->variable_duration = value;
   2433             celt_encoder_ctl(celt_enc, OPUS_SET_EXPERT_FRAME_DURATION(value));
   2434         }
   2435         break;
   2436         case OPUS_GET_EXPERT_FRAME_DURATION_REQUEST:
   2437         {
   2438             opus_int32 *value = va_arg(ap, opus_int32*);
   2439             if (!value)
   2440             {
   2441                goto bad_arg;
   2442             }
   2443             *value = st->variable_duration;
   2444         }
   2445         break;
   2446         case OPUS_SET_PREDICTION_DISABLED_REQUEST:
   2447         {
   2448            opus_int32 value = va_arg(ap, opus_int32);
   2449            if (value > 1 || value < 0)
   2450               goto bad_arg;
   2451            st->silk_mode.reducedDependency = value;
   2452         }
   2453         break;
   2454         case OPUS_GET_PREDICTION_DISABLED_REQUEST:
   2455         {
   2456            opus_int32 *value = va_arg(ap, opus_int32*);
   2457            if (!value)
   2458               goto bad_arg;
   2459            *value = st->silk_mode.reducedDependency;
   2460         }
   2461         break;
   2462         case OPUS_RESET_STATE:
   2463         {
   2464            void *silk_enc;
   2465            silk_EncControlStruct dummy;
   2466            char *start;
   2467            silk_enc = (char*)st+st->silk_enc_offset;
   2468 #ifndef DISABLE_FLOAT_API
   2469            tonality_analysis_reset(&st->analysis);
   2470 #endif
   2471 
   2472            start = (char*)&st->OPUS_ENCODER_RESET_START;
   2473            OPUS_CLEAR(start, sizeof(OpusEncoder) - (start - (char*)st));
   2474 
   2475            celt_encoder_ctl(celt_enc, OPUS_RESET_STATE);
   2476            silk_InitEncoder( silk_enc, st->arch, &dummy );
   2477            st->stream_channels = st->channels;
   2478            st->hybrid_stereo_width_Q14 = 1 << 14;
   2479            st->prev_HB_gain = Q15ONE;
   2480            st->first = 1;
   2481            st->mode = MODE_HYBRID;
   2482            st->bandwidth = OPUS_BANDWIDTH_FULLBAND;
   2483            st->variable_HP_smth2_Q15 = silk_LSHIFT( silk_lin2log( VARIABLE_HP_MIN_CUTOFF_HZ ), 8 );
   2484         }
   2485         break;
   2486         case OPUS_SET_FORCE_MODE_REQUEST:
   2487         {
   2488             opus_int32 value = va_arg(ap, opus_int32);
   2489             if ((value < MODE_SILK_ONLY || value > MODE_CELT_ONLY) && value != OPUS_AUTO)
   2490             {
   2491                goto bad_arg;
   2492             }
   2493             st->user_forced_mode = value;
   2494         }
   2495         break;
   2496         case OPUS_SET_LFE_REQUEST:
   2497         {
   2498             opus_int32 value = va_arg(ap, opus_int32);
   2499             st->lfe = value;
   2500             ret = celt_encoder_ctl(celt_enc, OPUS_SET_LFE(value));
   2501         }
   2502         break;
   2503         case OPUS_SET_ENERGY_MASK_REQUEST:
   2504         {
   2505             opus_val16 *value = va_arg(ap, opus_val16*);
   2506             st->energy_masking = value;
   2507             ret = celt_encoder_ctl(celt_enc, OPUS_SET_ENERGY_MASK(value));
   2508         }
   2509         break;
   2510 
   2511         case CELT_GET_MODE_REQUEST:
   2512         {
   2513            const CELTMode ** value = va_arg(ap, const CELTMode**);
   2514            if (!value)
   2515            {
   2516               goto bad_arg;
   2517            }
   2518            ret = celt_encoder_ctl(celt_enc, CELT_GET_MODE(value));
   2519         }
   2520         break;
   2521         default:
   2522             /* fprintf(stderr, "unknown opus_encoder_ctl() request: %d", request);*/
   2523             ret = OPUS_UNIMPLEMENTED;
   2524             break;
   2525     }
   2526     va_end(ap);
   2527     return ret;
   2528 bad_arg:
   2529     va_end(ap);
   2530     return OPUS_BAD_ARG;
   2531 }
   2532 
   2533 void opus_encoder_destroy(OpusEncoder *st)
   2534 {
   2535     opus_free(st);
   2536 }
   2537