path: root/silk/enc_API.c

/***********************************************************************
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, (subject to the limitations in the disclaimer below)
are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name of Skype Limited, nor the names of specific
contributors, may be used to endorse or promote products derived from
this software without specific prior written permission.
NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED
BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
***********************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "define.h"
#include "API.h"
#include "control.h"
#include "typedef.h"
#include "structs.h"
#include "tuning_parameters.h"
#ifdef FIXED_POINT
#include "main_FIX.h"
#else
#include "main_FLP.h"
#endif

/****************************************/
/* Encoder functions                    */
/****************************************/

opus_int silk_Get_Encoder_Size( int *encSizeBytes )
{
    opus_int ret = SILK_NO_ERROR;

    *encSizeBytes = sizeof( silk_encoder );

    return ret;
}

/*************************/
/* Init or Reset encoder */
/*************************/
opus_int silk_InitEncoder(
    void                            *encState,          /* I/O: State                                           */
    silk_EncControlStruct           *encStatus          /* O:   Control structure                               */
)
{
    silk_encoder *psEnc;
    opus_int n, ret = SILK_NO_ERROR;

    psEnc = (silk_encoder *)encState;

    /* Reset encoder */
    silk_memset( psEnc, 0, sizeof( silk_encoder ) );
    for( n = 0; n < ENCODER_NUM_CHANNELS; n++ ) {
        if( ret += silk_init_encoder( &psEnc->state_Fxx[ n ] ) ) {
            silk_assert( 0 );
        }
    }

    psEnc->nChannelsAPI = 1;
    psEnc->nChannelsInternal = 1;

    /* Read control structure */
    if( ret += silk_QueryEncoder( encState, encStatus ) ) {
        silk_assert( 0 );
    }

    return ret;
}

/***************************************/
/* Read control structure from encoder */
/***************************************/
opus_int silk_QueryEncoder(
    const void *encState,                       /* I:   State Vector                                    */
    silk_EncControlStruct *encStatus            /* O:   Control Structure                               */
)
{
    opus_int ret = SILK_NO_ERROR;
    silk_encoder_state_Fxx *state_Fxx;
    silk_encoder *psEnc = (silk_encoder *)encState;

    state_Fxx = psEnc->state_Fxx;

    encStatus->nChannelsAPI              = psEnc->nChannelsAPI;
    encStatus->nChannelsInternal         = psEnc->nChannelsInternal;
    encStatus->API_sampleRate            = state_Fxx[ 0 ].sCmn.API_fs_Hz;
    encStatus->maxInternalSampleRate     = state_Fxx[ 0 ].sCmn.maxInternal_fs_Hz;
    encStatus->minInternalSampleRate     = state_Fxx[ 0 ].sCmn.minInternal_fs_Hz;
    encStatus->desiredInternalSampleRate = state_Fxx[ 0 ].sCmn.desiredInternal_fs_Hz;
    encStatus->payloadSize_ms            = state_Fxx[ 0 ].sCmn.PacketSize_ms;
    encStatus->bitRate                   = state_Fxx[ 0 ].sCmn.TargetRate_bps;
    encStatus->packetLossPercentage      = state_Fxx[ 0 ].sCmn.PacketLoss_perc;
    encStatus->complexity                = state_Fxx[ 0 ].sCmn.Complexity;
    encStatus->useInBandFEC              = state_Fxx[ 0 ].sCmn.useInBandFEC;
    encStatus->useDTX                    = state_Fxx[ 0 ].sCmn.useDTX;
    encStatus->useCBR                    = state_Fxx[ 0 ].sCmn.useCBR;
    encStatus->internalSampleRate        = silk_SMULBB( state_Fxx[ 0 ].sCmn.fs_kHz, 1000 );
    encStatus->allowBandwidthSwitch      = state_Fxx[ 0 ].sCmn.allow_bandwidth_switch;
    encStatus->inWBmodeWithoutVariableLP = state_Fxx[ 0 ].sCmn.fs_kHz == 16 && state_Fxx[ 0 ].sCmn.sLP.mode == 0;

    return ret;
}


/**************************/
/* Encode frame with Silk */
/**************************/
opus_int silk_Encode(
    void                                *encState,      /* I/O: State                                           */
    silk_EncControlStruct               *encControl,    /* I:   Control structure                               */
    const opus_int16                     *samplesIn,     /* I:   Speech sample input vector                      */
    opus_int                             nSamplesIn,     /* I:   Number of samples in input vector               */
    ec_enc                              *psRangeEnc,    /* I/O  Compressor data structure                       */
    opus_int                             *nBytesOut,     /* I/O: Number of bytes in payload (input: Max bytes)   */
    const opus_int                       prefillFlag     /* I:   Flag to indicate prefilling buffers; no coding  */
)
{
    opus_int   n, i, nBits, flags, tmp_payloadSize_ms = 0, tmp_complexity = 0, ret = 0;
    opus_int   nSamplesToBuffer, nBlocksOf10ms, nSamplesFromInput = 0;
    opus_int   speech_act_thr_for_switch_Q8;
    opus_int32 TargetRate_bps, MStargetRates_bps[ 2 ], channelRate_bps, LBRR_symbol;
    silk_encoder *psEnc = ( silk_encoder * )encState;
    opus_int16 buf[ MAX_FRAME_LENGTH_MS * MAX_API_FS_KHZ + MAX_ENCODER_DELAY];
    opus_int transition, delay;

    psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded = psEnc->state_Fxx[ 1 ].sCmn.nFramesEncoded = 0;

    /* Check values in encoder control structure */
    if( ( ret = check_control_input( encControl ) != 0 ) ) {
        silk_assert( 0 );
        return ret;
    }

    if( encControl->nChannelsInternal > psEnc->nChannelsInternal ) {
        /* Mono -> Stereo transition: init state of second channel and stereo state */
        ret += silk_init_encoder( &psEnc->state_Fxx[ 1 ] );
        silk_memset( psEnc->sStereo.pred_prev_Q13, 0, sizeof( psEnc->sStereo.pred_prev_Q13 ) );
        silk_memset( psEnc->sStereo.sSide, 0, sizeof( psEnc->sStereo.sSide ) );
        psEnc->sStereo.mid_side_amp_Q0[ 0 ] = 0;
        psEnc->sStereo.mid_side_amp_Q0[ 1 ] = 1;
        psEnc->sStereo.mid_side_amp_Q0[ 2 ] = 0;
        psEnc->sStereo.mid_side_amp_Q0[ 3 ] = 1;
        psEnc->sStereo.width_prev_Q14 = 0;
        psEnc->sStereo.smth_width_Q14 = SILK_FIX_CONST( 1, 14 );
        if( psEnc->nChannelsAPI == 2 ) {
            silk_memcpy( &psEnc->state_Fxx[ 1 ].sCmn.resampler_state, &psEnc->state_Fxx[ 0 ].sCmn.resampler_state, sizeof( silk_resampler_state_struct ) );
            silk_memcpy( &psEnc->state_Fxx[ 1 ].sCmn.In_HP_State,     &psEnc->state_Fxx[ 0 ].sCmn.In_HP_State,     sizeof( psEnc->state_Fxx[ 1 ].sCmn.In_HP_State ) );
        }
    }

    transition = (encControl->payloadSize_ms != psEnc->state_Fxx[ 0 ].sCmn.PacketSize_ms) || (psEnc->nChannelsInternal != encControl->nChannelsInternal);

    psEnc->nChannelsAPI = encControl->nChannelsAPI;
    psEnc->nChannelsInternal = encControl->nChannelsInternal;

    nBlocksOf10ms = silk_DIV32( 100 * nSamplesIn, encControl->API_sampleRate );
    if( prefillFlag ) {
        /* Only accept input length of 10 ms */
        if( nBlocksOf10ms != 1 ) {
            ret = SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES;
            silk_assert( 0 );
            return ret;
        }
        /* Reset Encoder */
        for( n = 0; n < encControl->nChannelsInternal; n++ ) {
            if( (ret = silk_init_encoder( &psEnc->state_Fxx[ n ] ) ) != 0 ) {
                silk_assert( 0 );
            }
        }
        tmp_payloadSize_ms = encControl->payloadSize_ms;
        encControl->payloadSize_ms = 10;
        tmp_complexity = encControl->complexity;
        encControl->complexity = 0;
        for( n = 0; n < encControl->nChannelsInternal; n++ ) {
            psEnc->state_Fxx[ n ].sCmn.controlled_since_last_payload = 0;
            psEnc->state_Fxx[ n ].sCmn.prefillFlag = 1;
        }
    } else {
        /* Only accept input lengths that are a multiple of 10 ms */
        if( nBlocksOf10ms * encControl->API_sampleRate != 100 * nSamplesIn || nSamplesIn < 0 ) {
            ret = SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES;
            silk_assert( 0 );
            return ret;
        }
        /* Make sure no more than one packet can be produced */
        if( 1000 * (opus_int32)nSamplesIn > encControl->payloadSize_ms * encControl->API_sampleRate ) {
            ret = SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES;
            silk_assert( 0 );
            return ret;
        }
    }

    TargetRate_bps = silk_RSHIFT32( encControl->bitRate, encControl->nChannelsInternal - 1 );
    for( n = 0; n < encControl->nChannelsInternal; n++ ) {
        /* JMV: Force the side channel to the same rate as the mid. Is this the right way? */
        int force_fs_kHz = (n==1) ? psEnc->state_Fxx[0].sCmn.fs_kHz : 0;
        if( ( ret = silk_control_encoder( &psEnc->state_Fxx[ n ], encControl, TargetRate_bps, psEnc->allowBandwidthSwitch, n, force_fs_kHz ) ) != 0 ) {
            silk_assert( 0 );
            return ret;
        }
        if (psEnc->state_Fxx[n].sCmn.first_frame_after_reset || transition)
        {
            for( i = 0; i < psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket; i++ ) {
                psEnc->state_Fxx[ n ].sCmn.LBRR_flags[ i ] = 0;
            }
        }
        psEnc->state_Fxx[ n ].sCmn.inDTX = psEnc->state_Fxx[ n ].sCmn.useDTX;
    }
    silk_assert( encControl->nChannelsInternal == 1 || psEnc->state_Fxx[ 0 ].sCmn.fs_kHz == psEnc->state_Fxx[ 1 ].sCmn.fs_kHz );

    delay = psEnc->state_Fxx[ 0 ].sCmn.delay;
    /* Input buffering/resampling and encoding */
    while( 1 ) {
        nSamplesToBuffer  = psEnc->state_Fxx[ 0 ].sCmn.frame_length - psEnc->state_Fxx[ 0 ].sCmn.inputBufIx;
        nSamplesToBuffer  = silk_min( nSamplesToBuffer, 10 * nBlocksOf10ms * psEnc->state_Fxx[ 0 ].sCmn.fs_kHz );
        nSamplesFromInput = silk_DIV32_16( nSamplesToBuffer * psEnc->state_Fxx[ 0 ].sCmn.API_fs_Hz, psEnc->state_Fxx[ 0 ].sCmn.fs_kHz * 1000 );
        /* Resample and write to buffer */
        if( encControl->nChannelsAPI == 2 && encControl->nChannelsInternal == 2 ) {
            int id = psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded;
            for( n = 0; n < nSamplesFromInput; n++ ) {
                buf[ n+delay ] = samplesIn[ 2 * n ];
            }
            silk_memcpy(buf, &psEnc->state_Fxx[ 0 ].sCmn.delayBuf[ MAX_ENCODER_DELAY - delay ], delay * sizeof(opus_int16));
            /* Making sure to start both resamplers from the same state when switching from mono to stereo */
            if(psEnc->nPrevChannelsInternal == 1 && id==0) {
               silk_memcpy( &psEnc->state_Fxx[ 1 ].sCmn.resampler_state, &psEnc->state_Fxx[ 0 ].sCmn.resampler_state, sizeof(psEnc->state_Fxx[ 1 ].sCmn.resampler_state));
               silk_memcpy( &psEnc->state_Fxx[ 1 ].sCmn.delayBuf, &psEnc->state_Fxx[ 0 ].sCmn.delayBuf, MAX_ENCODER_DELAY*sizeof(opus_int16));
            }
            silk_memcpy(psEnc->state_Fxx[ 0 ].sCmn.delayBuf, buf + nSamplesFromInput + delay - MAX_ENCODER_DELAY, MAX_ENCODER_DELAY*sizeof(opus_int16));

            ret += silk_resampler( &psEnc->state_Fxx[ 0 ].sCmn.resampler_state,
                &psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.inputBufIx + 2 ], buf, nSamplesFromInput );
            psEnc->state_Fxx[ 0 ].sCmn.inputBufIx += nSamplesToBuffer;

            nSamplesToBuffer  = psEnc->state_Fxx[ 1 ].sCmn.frame_length - psEnc->state_Fxx[ 1 ].sCmn.inputBufIx;
            nSamplesToBuffer  = silk_min( nSamplesToBuffer, 10 * nBlocksOf10ms * psEnc->state_Fxx[ 1 ].sCmn.fs_kHz );
            for( n = 0; n < nSamplesFromInput; n++ ) {
                buf[ n + delay ] = samplesIn[ 2 * n + 1 ];
            }
            silk_memcpy(buf, &psEnc->state_Fxx[ 1 ].sCmn.delayBuf[ MAX_ENCODER_DELAY - delay ], delay * sizeof(opus_int16));
            ret += silk_resampler( &psEnc->state_Fxx[ 1 ].sCmn.resampler_state,
                &psEnc->state_Fxx[ 1 ].sCmn.inputBuf[ psEnc->state_Fxx[ 1 ].sCmn.inputBufIx + 2 ], buf, nSamplesFromInput );
            silk_memcpy(psEnc->state_Fxx[ 1 ].sCmn.delayBuf, buf + nSamplesFromInput + delay - MAX_ENCODER_DELAY, MAX_ENCODER_DELAY*sizeof(opus_int16));

            psEnc->state_Fxx[ 1 ].sCmn.inputBufIx += nSamplesToBuffer;
        } else if( encControl->nChannelsAPI == 2 && encControl->nChannelsInternal == 1 ) {
            /* Combine left and right channels before resampling */
            for( n = 0; n < nSamplesFromInput; n++ ) {
                buf[ n + delay ] = (opus_int16)silk_RSHIFT_ROUND( samplesIn[ 2 * n ] + samplesIn[ 2 * n + 1 ],  1 );
            }
            if(psEnc->nPrevChannelsInternal == 2 && psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded==0) {
               for ( n = 0; n<MAX_ENCODER_DELAY; n++ )
                  psEnc->state_Fxx[ 0 ].sCmn.delayBuf[ n ] = silk_RSHIFT(psEnc->state_Fxx[ 0 ].sCmn.delayBuf[ n ]+(opus_int32)psEnc->state_Fxx[ 1 ].sCmn.delayBuf[ n ], 1);
            }
            silk_memcpy(buf, &psEnc->state_Fxx[ 0 ].sCmn.delayBuf[ MAX_ENCODER_DELAY - delay ], delay * sizeof(opus_int16));
            ret += silk_resampler( &psEnc->state_Fxx[ 0 ].sCmn.resampler_state,
                &psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.inputBufIx + 2 ], buf, nSamplesFromInput );
            /* On the first mono frame, average the results for the two resampler states  */
            if (psEnc->nPrevChannelsInternal == 2 && psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded==0) {
               ret += silk_resampler( &psEnc->state_Fxx[ 1 ].sCmn.resampler_state,
                   &psEnc->state_Fxx[ 1 ].sCmn.inputBuf[ psEnc->state_Fxx[ 1 ].sCmn.inputBufIx + 2 ], buf, nSamplesFromInput );
               for ( n = 0; n < psEnc->state_Fxx[ 0 ].sCmn.frame_length; n++ ) {
                  psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.inputBufIx+n+2 ] =
                        silk_RSHIFT(psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.inputBufIx+n+2 ]
                                  + psEnc->state_Fxx[ 1 ].sCmn.inputBuf[ psEnc->state_Fxx[ 1 ].sCmn.inputBufIx+n+2 ], 1);
               }
            }
            silk_memcpy(psEnc->state_Fxx[ 0 ].sCmn.delayBuf, buf + nSamplesFromInput + delay - MAX_ENCODER_DELAY, MAX_ENCODER_DELAY*sizeof(opus_int16));
            psEnc->state_Fxx[ 0 ].sCmn.inputBufIx += nSamplesToBuffer;
        } else {
            silk_assert( encControl->nChannelsAPI == 1 && encControl->nChannelsInternal == 1 );
            silk_memcpy(buf + delay, samplesIn, nSamplesFromInput*sizeof(opus_int16));
            silk_memcpy(buf, &psEnc->state_Fxx[ 0 ].sCmn.delayBuf[ MAX_ENCODER_DELAY - delay ], delay * sizeof(opus_int16));
            ret += silk_resampler( &psEnc->state_Fxx[ 0 ].sCmn.resampler_state,
                &psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.inputBufIx + 2 ], buf, nSamplesFromInput );
            silk_memcpy(psEnc->state_Fxx[ 0 ].sCmn.delayBuf, buf + nSamplesFromInput + delay - MAX_ENCODER_DELAY, MAX_ENCODER_DELAY*sizeof(opus_int16));
            psEnc->state_Fxx[ 0 ].sCmn.inputBufIx += nSamplesToBuffer;
        }

        samplesIn  += nSamplesFromInput * encControl->nChannelsAPI;
        nSamplesIn -= nSamplesFromInput;

        /* Default */
        psEnc->allowBandwidthSwitch = 0;

        /* Silk encoder */
        if( psEnc->state_Fxx[ 0 ].sCmn.inputBufIx >= psEnc->state_Fxx[ 0 ].sCmn.frame_length ) {
            /* Enough data in input buffer, so encode */
            silk_assert( psEnc->state_Fxx[ 0 ].sCmn.inputBufIx == psEnc->state_Fxx[ 0 ].sCmn.frame_length );
            silk_assert( encControl->nChannelsInternal == 1 || psEnc->state_Fxx[ 1 ].sCmn.inputBufIx == psEnc->state_Fxx[ 1 ].sCmn.frame_length );

            /* Deal with LBRR data */
            if( psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded == 0 && !prefillFlag ) {
                /* Create space at start of payload for VAD and FEC flags */
                opus_uint8 iCDF[ 2 ] = { 0, 0 };
                iCDF[ 0 ] = 256 - silk_RSHIFT( 256, ( psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket + 1 ) * encControl->nChannelsInternal );
                ec_enc_icdf( psRangeEnc, 0, iCDF, 8 );

                /* Encode any LBRR data from previous packet */
                /* Encode LBRR flags */
                for( n = 0; n < encControl->nChannelsInternal; n++ ) {
                    LBRR_symbol = 0;
                    for( i = 0; i < psEnc->state_Fxx[ n ].sCmn.nFramesPerPacket; i++ ) {
                        LBRR_symbol |= silk_LSHIFT( psEnc->state_Fxx[ n ].sCmn.LBRR_flags[ i ], i );
                    }
                    psEnc->state_Fxx[ n ].sCmn.LBRR_flag = LBRR_symbol > 0 ? 1 : 0;
                    if( LBRR_symbol && psEnc->state_Fxx[ n ].sCmn.nFramesPerPacket > 1 ) {
                        ec_enc_icdf( psRangeEnc, LBRR_symbol - 1, silk_LBRR_flags_iCDF_ptr[ psEnc->state_Fxx[ n ].sCmn.nFramesPerPacket - 2 ], 8 );
                    }
                }

                /* Code LBRR indices and excitation signals */
                for( i = 0; i < psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket; i++ ) {
                    for( n = 0; n < encControl->nChannelsInternal; n++ ) {
                        if( psEnc->state_Fxx[ n ].sCmn.LBRR_flags[ i ] ) {
                            opus_int condCoding;

                            if( encControl->nChannelsInternal == 2 && n == 0 ) {
                                silk_stereo_encode_pred( psRangeEnc, psEnc->sStereo.predIx[ i ] );
                                /* For LBRR data there's no need to code the mid-only flag if the side-channel LBRR flag is set */
                                if( psEnc->state_Fxx[ 1 ].sCmn.LBRR_flags[ i ] == 0 ) {
                                    silk_stereo_encode_mid_only( psRangeEnc, psEnc->sStereo.mid_only_flags[ i ] );
                                }
                            }
                            /* Use conditional coding if previous frame available */
                            if( i > 0 && psEnc->state_Fxx[ n ].sCmn.LBRR_flags[ i - 1 ] ) {
                                condCoding = CODE_CONDITIONALLY;
                            } else {
                                condCoding = CODE_INDEPENDENTLY;
                            }
                            silk_encode_indices( &psEnc->state_Fxx[ n ].sCmn, psRangeEnc, i, 1, condCoding );
                            silk_encode_pulses( psRangeEnc, psEnc->state_Fxx[ n ].sCmn.indices_LBRR[i].signalType, psEnc->state_Fxx[ n ].sCmn.indices_LBRR[i].quantOffsetType,
                                psEnc->state_Fxx[ n ].sCmn.pulses_LBRR[ i ], psEnc->state_Fxx[ n ].sCmn.frame_length );
                        }
                    }
                }

                /* Reset LBRR flags */
                for( n = 0; n < encControl->nChannelsInternal; n++ ) {
                    silk_memset( psEnc->state_Fxx[ n ].sCmn.LBRR_flags, 0, sizeof( psEnc->state_Fxx[ n ].sCmn.LBRR_flags ) );
                }
            }

            silk_HP_variable_cutoff( psEnc->state_Fxx );

            /* Total target bits for packet */
            nBits = silk_DIV32_16( silk_MUL( encControl->bitRate, encControl->payloadSize_ms ), 1000 );
            /* Subtract half of the bits already used */
            if (!prefillFlag)
                nBits -= ec_tell( psRangeEnc ) >> 1;
            /* Divide by number of uncoded frames left in packet */
            nBits = silk_DIV32_16( nBits, psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket - psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded );
            /* Convert to bits/second */
            if( encControl->payloadSize_ms == 10 ) {
                TargetRate_bps = silk_SMULBB( nBits, 100 );
            } else {
                TargetRate_bps = silk_SMULBB( nBits, 50 );
            }
            /* Subtract fraction of bits in excess of target in previous packets */
            TargetRate_bps -= silk_DIV32_16( silk_MUL( psEnc->nBitsExceeded, 1000 ), BITRESERVOIR_DECAY_TIME_MS );
            /* Never exceed input bitrate */
            TargetRate_bps = silk_LIMIT( TargetRate_bps, encControl->bitRate, 5000 );

            /* Convert Left/Right to Mid/Side */
            if( encControl->nChannelsInternal == 2 ) {
                silk_stereo_LR_to_MS( &psEnc->sStereo, &psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ 2 ], &psEnc->state_Fxx[ 1 ].sCmn.inputBuf[ 2 ],
                    psEnc->sStereo.predIx[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ], &psEnc->sStereo.mid_only_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ],
                    MStargetRates_bps, TargetRate_bps, psEnc->state_Fxx[ 0 ].sCmn.speech_activity_Q8, encControl->toMono,
                    psEnc->state_Fxx[ 0 ].sCmn.fs_kHz, psEnc->state_Fxx[ 0 ].sCmn.frame_length );
                if( psEnc->sStereo.mid_only_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ] == 0 ) {
                    /* Reset side channel encoder memory for first frame with side coding */
                    if( psEnc->prev_decode_only_middle == 1 ) {
                        silk_memset( &psEnc->state_Fxx[ 1 ].sShape,               0, sizeof( psEnc->state_Fxx[ 1 ].sShape ) );
                        silk_memset( &psEnc->state_Fxx[ 1 ].sPrefilt,             0, sizeof( psEnc->state_Fxx[ 1 ].sPrefilt ) );
                        silk_memset( &psEnc->state_Fxx[ 1 ].sCmn.sNSQ,            0, sizeof( psEnc->state_Fxx[ 1 ].sCmn.sNSQ ) );
                        silk_memset( psEnc->state_Fxx[ 1 ].sCmn.prev_NLSFq_Q15,   0, sizeof( psEnc->state_Fxx[ 1 ].sCmn.prev_NLSFq_Q15 ) );
                        silk_memset( &psEnc->state_Fxx[ 1 ].sCmn.sLP.In_LP_State, 0, sizeof( psEnc->state_Fxx[ 1 ].sCmn.sLP.In_LP_State ) );
                        psEnc->state_Fxx[ 1 ].sCmn.prevLag                = 100;
                        psEnc->state_Fxx[ 1 ].sCmn.sNSQ.lagPrev           = 100;
                        psEnc->state_Fxx[ 1 ].sShape.LastGainIndex        = 10;
                        psEnc->state_Fxx[ 1 ].sCmn.prevSignalType         = TYPE_NO_VOICE_ACTIVITY;
                        psEnc->state_Fxx[ 1 ].sCmn.sNSQ.prev_inv_gain_Q16 = 65536;
                        psEnc->state_Fxx[ 1 ].sCmn.first_frame_after_reset = 1;
                    }
                    silk_encode_do_VAD_Fxx( &psEnc->state_Fxx[ 1 ] );
                } else {
                    psEnc->state_Fxx[ 1 ].sCmn.VAD_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ] = 0;
                }
                if( !prefillFlag ) {
                    silk_stereo_encode_pred( psRangeEnc, psEnc->sStereo.predIx[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ] );
                    if( psEnc->state_Fxx[ 1 ].sCmn.VAD_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ] == 0 ) {
                        silk_stereo_encode_mid_only( psRangeEnc, psEnc->sStereo.mid_only_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded ] );
                    }
                }
            } else {
                /* Buffering */
                silk_memcpy( psEnc->state_Fxx[ 0 ].sCmn.inputBuf, psEnc->sStereo.sMid, 2 * sizeof( opus_int16 ) );
                silk_memcpy( psEnc->sStereo.sMid, &psEnc->state_Fxx[ 0 ].sCmn.inputBuf[ psEnc->state_Fxx[ 0 ].sCmn.frame_length ], 2 * sizeof( opus_int16 ) );
            }
            silk_encode_do_VAD_Fxx( &psEnc->state_Fxx[ 0 ] );

            /* Encode */
            for( n = 0; n < encControl->nChannelsInternal; n++ ) {
                if( encControl->nChannelsInternal == 1 ) {
                    channelRate_bps = TargetRate_bps;
                } else {
                    channelRate_bps = MStargetRates_bps[ n ];
                }

                if( channelRate_bps > 0 ) {
                    opus_int condCoding;

                    silk_control_SNR( &psEnc->state_Fxx[ n ].sCmn, channelRate_bps );

                    /* Use independent coding if no previous frame available */
                    if( psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded - n <= 0 ) {
                        condCoding = CODE_INDEPENDENTLY;
                    } else if( n > 0 && psEnc->prev_decode_only_middle ) {
                        /* If we skipped a side frame in this packet, we don't
                           need LTP scaling; the LTP state is well-defined. */
                        condCoding = CODE_INDEPENDENTLY_NO_LTP_SCALING;
                    } else {
                        condCoding = CODE_CONDITIONALLY;
                    }
                    if( ( ret = silk_encode_frame_Fxx( &psEnc->state_Fxx[ n ], nBytesOut, psRangeEnc, condCoding ) ) != 0 ) {
                        silk_assert( 0 );
                    }
                }
                psEnc->state_Fxx[ n ].sCmn.controlled_since_last_payload = 0;
                psEnc->state_Fxx[ n ].sCmn.inputBufIx = 0;
                psEnc->state_Fxx[ n ].sCmn.nFramesEncoded++;
            }
            psEnc->prev_decode_only_middle = psEnc->sStereo.mid_only_flags[ psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded - 1 ];

            /* Insert VAD and FEC flags at beginning of bitstream */
            if( *nBytesOut > 0 && psEnc->state_Fxx[ 0 ].sCmn.nFramesEncoded == psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket) {
                flags = 0;
                for( n = 0; n < encControl->nChannelsInternal; n++ ) {
                    for( i = 0; i < psEnc->state_Fxx[ n ].sCmn.nFramesPerPacket; i++ ) {
                        flags  = silk_LSHIFT( flags, 1 );
                        flags |= psEnc->state_Fxx[ n ].sCmn.VAD_flags[ i ];
                    }
                    flags  = silk_LSHIFT( flags, 1 );
                    flags |= psEnc->state_Fxx[ n ].sCmn.LBRR_flag;
                }
                if( !prefillFlag ) {
                    ec_enc_patch_initial_bits( psRangeEnc, flags, ( psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket + 1 ) * encControl->nChannelsInternal );
                }

                /* Return zero bytes if all channels DTXed */
                if( psEnc->state_Fxx[ 0 ].sCmn.inDTX && ( encControl->nChannelsInternal == 1 || psEnc->state_Fxx[ 1 ].sCmn.inDTX ) ) {
                    *nBytesOut = 0;
                }

                psEnc->nBitsExceeded += *nBytesOut * 8;
                psEnc->nBitsExceeded -= silk_DIV32_16( silk_MUL( encControl->bitRate, encControl->payloadSize_ms ), 1000 );
                psEnc->nBitsExceeded  = silk_LIMIT( psEnc->nBitsExceeded, 0, 10000 );

                /* Update flag indicating if bandwidth switching is allowed */
                speech_act_thr_for_switch_Q8 = silk_SMLAWB( SILK_FIX_CONST( SPEECH_ACTIVITY_DTX_THRES, 8 ),
                    SILK_FIX_CONST( ( 1 - SPEECH_ACTIVITY_DTX_THRES ) / MAX_BANDWIDTH_SWITCH_DELAY_MS, 16 + 8 ), psEnc->timeSinceSwitchAllowed_ms );
                if( psEnc->state_Fxx[ 0 ].sCmn.speech_activity_Q8 < speech_act_thr_for_switch_Q8 ) {
                    psEnc->allowBandwidthSwitch = 1;
                    psEnc->timeSinceSwitchAllowed_ms = 0;
                } else {
                    psEnc->allowBandwidthSwitch = 0;
                    psEnc->timeSinceSwitchAllowed_ms += encControl->payloadSize_ms;
                }
            }

            if( nSamplesIn == 0 ) {
                break;
            }
        } else {
            break;
        }
    }

    psEnc->nPrevChannelsInternal = encControl->nChannelsInternal;

    encControl->allowBandwidthSwitch = psEnc->allowBandwidthSwitch;
    encControl->inWBmodeWithoutVariableLP = psEnc->state_Fxx[ 0 ].sCmn.fs_kHz == 16 && psEnc->state_Fxx[ 0 ].sCmn.sLP.mode == 0;
    encControl->internalSampleRate = silk_SMULBB( psEnc->state_Fxx[ 0 ].sCmn.fs_kHz, 1000 );
    encControl->stereoWidth_Q14 = encControl->toMono ? 0 : psEnc->sStereo.smth_width_Q14;
    if( prefillFlag ) {
        encControl->payloadSize_ms = tmp_payloadSize_ms;
        encControl->complexity = tmp_complexity;
        for( n = 0; n < encControl->nChannelsInternal; n++ ) {
            psEnc->state_Fxx[ n ].sCmn.controlled_since_last_payload = 0;
            psEnc->state_Fxx[ n ].sCmn.prefillFlag = 0;
        }
    }

    return ret;
}